Merge tag 'linux-watchdog-4.16-rc1' of git://www.linux-watchdog.org/linux-watchdog

Pull watchdog updates from Wim Van Sebroeck:

 - new watchdog device drivers for Realtek RTD1295 and Spreadtrum SC9860
   platform

 - add support for the following devices: jz4780 SoC, AST25xx series SoC
   and r8a77970 SoC

 - convert to watchdog framework: i6300esb_wdt, xen_wdt and sp5100_tco

 - several fixes for watchdog core

 - remove at32ap700x and obsolete documentation

 - gpio: Convert to use GPIO descriptors

 - rename gemini into FTWDT010 as this IP block is generc from Faraday
   Technology

 - various clean-ups and small bugfixes

 - add Guenter Roeck as co-maintainer

 - change maintainers e-mail address

* tag 'linux-watchdog-4.16-rc1' of git://www.linux-watchdog.org/linux-watchdog: (74 commits)
  documentation: watchdog: remove documentation of w83697hf_wdt/w83697ug_wdt
  documentation: watchdog: remove documentation for ixp2000
  documentation: watchdog: remove documentation of at32ap700x_wdt
  watchdog: remove at32ap700x_wdt
  watchdog: sp5100_tco: Add support for recent FCH versions
  watchdog: sp5100-tco: Abort if watchdog is disabled by hardware
  watchdog: sp5100_tco: Use bit operations
  watchdog: sp5100_tco: Convert to use watchdog subsystem
  watchdog: sp5100_tco: Clean up function and variable names
  watchdog: sp5100_tco: Use dev_ print functions where possible
  watchdog: sp5100_tco: Match PCI device early
  watchdog: sp5100_tco: Clean up sp5100_tco_setupdevice
  watchdog: sp5100_tco: Use standard error codes
  watchdog: sp5100_tco: Use request_muxed_region where possible
  watchdog: sp5100_tco: Fix watchdog disable bit
  watchdog: sp5100_tco: Always use SP5100_IO_PM_{INDEX_REG,DATA_REG}
  watchdog: core: make sure the watchdog_worker is not deferred
  watchdog: mt7621: switch to using managed devm_watchdog_register_device()
  watchdog: mt7621: set WDOG_HW_RUNNING bit when appropriate
  watchdog: imx2_wdt: restore previous timeout after suspend+resume
  ...

Documentation/devicetree/bindings/watchdog/cortina,gemini-watchdog.txt

-Cortina Systems Gemini SoC Watchdog
-
-Required properties:
-- compatible : must be "cortina,gemini-watchdog"
-- reg : shall contain base register location and length
-- interrupts : shall contain the interrupt for the watchdog
-
-Optional properties:
-- timeout-sec : the default watchdog timeout in seconds.
-
-Example:
-
-watchdog@41000000 {
-	compatible = "cortina,gemini-watchdog";
-	reg = <0x41000000 0x1000>;
-	interrupts = <3 IRQ_TYPE_LEVEL_HIGH>;
-};

Documentation/devicetree/bindings/watchdog/cortina,gemin-watchdog.txt → Documentation/devicetree/bindings/watchdog/faraday,ftwdt010.txt

-Cortina Systems Gemini SoC Watchdog
+Faraday Technology FTWDT010 watchdog
+
+This is an IP part from Faraday Technology found in the Gemini
+SoCs and others.
 
 Required properties:
-- compatible : must be "cortina,gemini-watchdog"
+- compatible : must be one of
+  "faraday,ftwdt010"
+  "cortina,gemini-watchdog", "faraday,ftwdt010"
 - reg : shall contain base register location and length
 - interrupts : shall contain the interrupt for the watchdog
 
@@ -11,7 +16,7 @@ Optional properties:
 Example:
 
 watchdog@41000000 {
-	compatible = "cortina,gemini-watchdog";
+	compatible = "faraday,ftwdt010";
 	reg = <0x41000000 0x1000>;
 	interrupts = <3 IRQ_TYPE_LEVEL_HIGH>;
 };

Documentation/devicetree/bindings/watchdog/ingenic,jz4740-wdt.txt

-Ingenic Watchdog Timer (WDT) Controller for JZ4740
+Ingenic Watchdog Timer (WDT) Controller for JZ4740 & JZ4780
 
 Required properties:
-compatible: "ingenic,jz4740-watchdog"
+compatible: "ingenic,jz4740-watchdog" or "ingenic,jz4780-watchdog"
 reg: Register address and length for watchdog registers
 
 Example:

Documentation/devicetree/bindings/watchdog/realtek,rtd119x.txt

+Realtek RTD1295 Watchdog
+========================
+
+Required properties:
+
+- compatible :  Should be "realtek,rtd1295-watchdog"
+- reg        :  Specifies the physical base address and size of registers
+- clocks     :  Specifies one clock input
+
+
+Example:
+
+	watchdog@98007680 {
+		compatible = "realtek,rtd1295-watchdog";
+		reg = <0x98007680 0x100>;
+		clocks = <&osc27M>;
+	};

Documentation/devicetree/bindings/watchdog/renesas-wdt.txt

@@ -4,10 +4,11 @@ Required properties:
 - compatible : Should be "renesas,<soctype>-wdt", and
 	       "renesas,rcar-gen3-wdt" or "renesas,rza-wdt" as fallback.
 	       Examples with soctypes are:
+	         - "renesas,r7s72100-wdt" (RZ/A1)
 	         - "renesas,r8a7795-wdt" (R-Car H3)
 	         - "renesas,r8a7796-wdt" (R-Car M3-W)
+	         - "renesas,r8a77970-wdt" (R-Car V3M)
 	         - "renesas,r8a77995-wdt" (R-Car D3)
-	         - "renesas,r7s72100-wdt" (RZ/A1)
 
   When compatible with the generic version, nodes must list the SoC-specific
   version corresponding to the platform first, followed by the generic

Documentation/devicetree/bindings/watchdog/sprd-wdt.txt

+Spreadtrum SoCs Watchdog timer
+
+Required properties:
+- compatible : Should be "sprd,sp9860-wdt".
+- reg : Specifies base physical address and size of the registers.
+- interrupts : Exactly one interrupt specifier.
+- timeout-sec : Contain the default watchdog timeout in seconds.
+- clock-names : Contain the input clock names.
+- clocks : Phandles to input clocks.
+
+Example:
+	watchdog: watchdog@40310000 {
+		compatible = "sprd,sp9860-wdt";
+		reg = <0 0x40310000 0 0x1000>;
+		interrupts = <GIC_SPI 61 IRQ_TYPE_LEVEL_HIGH>;
+		timeout-sec = <12>;
+		clock-names = "enable", "rtc_enable";
+		clocks = <&clk_aon_apb_gates1 8>, <&clk_aon_apb_rtc_gates 9>;
+	};

Documentation/watchdog/watchdog-parameters.txt

@@ -40,11 +40,6 @@ margin: Watchdog margin in seconds (default=60)
 nowayout: Disable watchdog shutdown on close
 	(default=kernel config parameter)
 -------------------------------------------------
-at32ap700x_wdt:
-timeout: Timeout value. Limited to be 1 or 2 seconds. (default=2)
-nowayout: Watchdog cannot be stopped once started
-	(default=kernel config parameter)
--------------------------------------------------
 at91rm9200_wdt:
 wdt_time: Watchdog time in seconds. (default=5)
 nowayout: Watchdog cannot be stopped once started
@@ -162,11 +157,6 @@ testmode: Watchdog test mode (1 = no reboot), default=0
 nowayout: Watchdog cannot be stopped once started
 	(default=kernel config parameter)
 -------------------------------------------------
-ixp2000_wdt:
-heartbeat: Watchdog heartbeat in seconds (default 60s)
-nowayout: Watchdog cannot be stopped once started
-	(default=kernel config parameter)
--------------------------------------------------
 ixp4xx_wdt:
 heartbeat: Watchdog heartbeat in seconds (default 60s)
 nowayout: Watchdog cannot be stopped once started
@@ -381,19 +371,6 @@ timeout: Watchdog timeout in seconds. 1 <= timeout <= 255, default=60.
 nowayout: Watchdog cannot be stopped once started
 	(default=kernel config parameter)
 -------------------------------------------------
-w83697hf_wdt:
-wdt_io: w83697hf/hg WDT io port (default 0x2e, 0 = autodetect)
-timeout: Watchdog timeout in seconds. 1<= timeout <=255 (default=60)
-nowayout: Watchdog cannot be stopped once started
-	(default=kernel config parameter)
-early_disable: Watchdog gets disabled at boot time (default=1)
--------------------------------------------------
-w83697ug_wdt:
-wdt_io: w83697ug/uf WDT io port (default 0x2e)
-timeout: Watchdog timeout in seconds. 1<= timeout <=255 (default=60)
-nowayout: Watchdog cannot be stopped once started
-	(default=kernel config parameter)
--------------------------------------------------
 w83877f_wdt:
 timeout: Watchdog timeout in seconds. (1<=timeout<=3600, default=30)
 nowayout: Watchdog cannot be stopped once started

MAINTAINERS

@@ -14991,8 +14991,8 @@ S:	Maintained
 F:	drivers/input/tablet/wacom_serial4.c
 
 WATCHDOG DEVICE DRIVERS
-M:	Wim Van Sebroeck <wim@iguana.be>
-R:	Guenter Roeck <linux@roeck-us.net>
+M:	Wim Van Sebroeck <wim@linux-watchdog.org>
+M:	Guenter Roeck <linux@roeck-us.net>
 L:	linux-watchdog@vger.kernel.org
 W:	http://www.linux-watchdog.org/
 T:	git git://www.linux-watchdog.org/linux-watchdog.git

drivers/watchdog/Kconfig

@@ -328,16 +328,18 @@ config 977_WATCHDOG
 
 	  Not sure? It's safe to say N.
 
-config GEMINI_WATCHDOG
-	tristate "Gemini watchdog"
-	depends on ARCH_GEMINI
+config FTWDT010_WATCHDOG
+	tristate "Faraday Technology FTWDT010 watchdog"
+	depends on ARM || COMPILE_TEST
 	select WATCHDOG_CORE
+	default ARCH_GEMINI
 	help
-	  Say Y here if to include support for the watchdog timer
-	  embedded in the Cortina Systems Gemini family of devices.
+	  Say Y here if to include support for the Faraday Technology
+	  FTWDT010 watchdog timer embedded in the Cortina Systems Gemini
+	  family of devices.
 
 	  To compile this driver as a module, choose M here: the
-	  module will be called gemini_wdt.
+	  module will be called ftwdt010_wdt.
 
 config IXP4XX_WATCHDOG
 	tristate "IXP4xx Watchdog"
@@ -748,12 +750,12 @@ config RENESAS_RZAWDT
 	  Renesas RZ/A SoCs. These watchdogs can be used to reset a system.
 
 config ASPEED_WATCHDOG
-	tristate "Aspeed 2400 watchdog support"
+	tristate "Aspeed BMC watchdog support"
 	depends on ARCH_ASPEED || COMPILE_TEST
 	select WATCHDOG_CORE
 	help
 	  Say Y here to include support for the watchdog timer
-	  in Apseed BMC SoCs.
+	  in Aspeed BMC SoCs.
 
 	  This driver is required to reboot the SoC.
 
@@ -794,14 +796,23 @@ config UNIPHIER_WATCHDOG
 	  To compile this driver as a module, choose M here: the
 	  module will be called uniphier_wdt.
 
-# AVR32 Architecture
+config RTD119X_WATCHDOG
+	bool "Realtek RTD119x/RTD129x watchdog support"
+	depends on ARCH_REALTEK || COMPILE_TEST
+	depends on OF
+	select WATCHDOG_CORE
+	default ARCH_REALTEK
+	help
+	  Say Y here to include support for the watchdog timer in
+	  Realtek RTD1295 SoCs.
 
-config AT32AP700X_WDT
-	tristate "AT32AP700x watchdog"
-	depends on CPU_AT32AP700X || COMPILE_TEST
+config SPRD_WATCHDOG
+	tristate "Spreadtrum watchdog support"
+	depends on ARCH_SPRD || COMPILE_TEST
+	select WATCHDOG_CORE
 	help
-	  Watchdog timer embedded into AT32AP700x devices. This will reboot
-	  your system when the timeout is reached.
+	  Say Y here to include watchdog timer supported
+	  by Spreadtrum system.
 
 # BLACKFIN Architecture
 
@@ -1458,7 +1469,7 @@ config RC32434_WDT
 
 config INDYDOG
 	tristate "Indy/I2 Hardware Watchdog"
-	depends on SGI_HAS_INDYDOG || (MIPS && COMPILE_TEST)
+	depends on SGI_HAS_INDYDOG
 	help
 	  Hardware driver for the Indy's/I2's watchdog. This is a
 	  watchdog timer that will reboot the machine after a 60 second

drivers/watchdog/Makefile

@@ -46,7 +46,7 @@ obj-$(CONFIG_OMAP_WATCHDOG) += omap_wdt.o
 obj-$(CONFIG_TWL4030_WATCHDOG) += twl4030_wdt.o
 obj-$(CONFIG_21285_WATCHDOG) += wdt285.o
 obj-$(CONFIG_977_WATCHDOG) += wdt977.o
-obj-$(CONFIG_GEMINI_WATCHDOG) += gemini_wdt.o
+obj-$(CONFIG_FTWDT010_WATCHDOG) += ftwdt010_wdt.o
 obj-$(CONFIG_IXP4XX_WATCHDOG) += ixp4xx_wdt.o
 obj-$(CONFIG_KS8695_WATCHDOG) += ks8695_wdt.o
 obj-$(CONFIG_S3C2410_WATCHDOG) += s3c2410_wdt.o
@@ -88,9 +88,8 @@ obj-$(CONFIG_ASPEED_WATCHDOG) += aspeed_wdt.o
 obj-$(CONFIG_ZX2967_WATCHDOG) += zx2967_wdt.o
 obj-$(CONFIG_STM32_WATCHDOG) += stm32_iwdg.o
 obj-$(CONFIG_UNIPHIER_WATCHDOG) += uniphier_wdt.o
-
-# AVR32 Architecture
-obj-$(CONFIG_AT32AP700X_WDT) += at32ap700x_wdt.o
+obj-$(CONFIG_RTD119X_WATCHDOG) += rtd119x_wdt.o
+obj-$(CONFIG_SPRD_WATCHDOG) += sprd_wdt.o
 
 # BLACKFIN Architecture
 obj-$(CONFIG_BFIN_WDT) += bfin_wdt.o

drivers/watchdog/advantechwdt.c

@@ -181,7 +181,7 @@ static long advwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		if (advwdt_set_heartbeat(new_timeout))
 			return -EINVAL;
 		advwdt_ping();
-		/* Fall */
+		/* fall through */
 	case WDIOC_GETTIMEOUT:
 		return put_user(timeout, p);
 	default:

drivers/watchdog/alim1535_wdt.c

@@ -223,8 +223,8 @@ static long ali_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		if (ali_settimer(new_timeout))
 			return -EINVAL;
 		ali_keepalive();
-		/* Fall */
 	}
+		/* fall through */
 	case WDIOC_GETTIMEOUT:
 		return put_user(timeout, p);
 	default:

drivers/watchdog/aspeed_wdt.c

@@ -243,9 +243,13 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
 	if (of_property_read_bool(np, "aspeed,external-signal"))
 		wdt->ctrl |= WDT_CTRL_WDT_EXT;
 
-	writel(wdt->ctrl, wdt->base + WDT_CTRL);
-
 	if (readl(wdt->base + WDT_CTRL) & WDT_CTRL_ENABLE)  {
+		/*
+		 * The watchdog is running, but invoke aspeed_wdt_start() to
+		 * write wdt->ctrl to WDT_CTRL to ensure the watchdog's
+		 * configuration conforms to the driver's expectations.
+		 * Primarily, ensure we're using the 1MHz clock source.
+		 */
 		aspeed_wdt_start(&wdt->wdd);
 		set_bit(WDOG_HW_RUNNING, &wdt->wdd.status);
 	}
@@ -312,7 +316,18 @@ static struct platform_driver aspeed_watchdog_driver = {
 		.of_match_table = of_match_ptr(aspeed_wdt_of_table),
 	},
 };
-module_platform_driver(aspeed_watchdog_driver);
+
+static int __init aspeed_wdt_init(void)
+{
+	return platform_driver_register(&aspeed_watchdog_driver);
+}
+arch_initcall(aspeed_wdt_init);
+
+static void __exit aspeed_wdt_exit(void)
+{
+	platform_driver_unregister(&aspeed_watchdog_driver);
+}
+module_exit(aspeed_wdt_exit);
 
 MODULE_DESCRIPTION("Aspeed Watchdog Driver");
 MODULE_LICENSE("GPL");

drivers/watchdog/at32ap700x_wdt.c

-/*
- * Watchdog driver for Atmel AT32AP700X devices
- *
- * Copyright (C) 2005-2006 Atmel Corporation
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- *
- * Errata: WDT Clear is blocked after WDT Reset
- *
- * A watchdog timer event will, after reset, block writes to the WDT_CLEAR
- * register, preventing the program to clear the next Watchdog Timer Reset.
- *
- * If you still want to use the WDT after a WDT reset a small code can be
- * insterted at the startup checking the AVR32_PM.rcause register for WDT reset
- * and use a GPIO pin to reset the system. This method requires that one of the
- * GPIO pins are available and connected externally to the RESET_N pin. After
- * the GPIO pin has pulled down the reset line the GPIO will be reset and leave
- * the pin tristated with pullup.
- */
-
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/miscdevice.h>
-#include <linux/fs.h>
-#include <linux/platform_device.h>
-#include <linux/watchdog.h>
-#include <linux/uaccess.h>
-#include <linux/io.h>
-#include <linux/spinlock.h>
-#include <linux/slab.h>
-
-#define TIMEOUT_MIN		1
-#define TIMEOUT_MAX		2
-#define TIMEOUT_DEFAULT		TIMEOUT_MAX
-
-/* module parameters */
-static int timeout =  TIMEOUT_DEFAULT;
-module_param(timeout, int, 0);
-MODULE_PARM_DESC(timeout,
-		"Timeout value. Limited to be 1 or 2 seconds. (default="
-		__MODULE_STRING(TIMEOUT_DEFAULT) ")");
-
-static bool nowayout = WATCHDOG_NOWAYOUT;
-module_param(nowayout, bool, 0);
-MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
-		__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
-
-/* Watchdog registers and write/read macro */
-#define WDT_CTRL		0x00
-#define WDT_CTRL_EN		   0
-#define WDT_CTRL_PSEL		   8
-#define WDT_CTRL_KEY		  24
-
-#define WDT_CLR			0x04
-
-#define WDT_RCAUSE		0x10
-#define WDT_RCAUSE_POR		   0
-#define WDT_RCAUSE_EXT		   2
-#define WDT_RCAUSE_WDT		   3
-#define WDT_RCAUSE_JTAG		   4
-#define WDT_RCAUSE_SERP		   5
-
-#define WDT_BIT(name)		(1 << WDT_##name)
-#define WDT_BF(name, value)	((value) << WDT_##name)
-
-#define wdt_readl(dev, reg)				\
-	__raw_readl((dev)->regs + WDT_##reg)
-#define wdt_writel(dev, reg, value)			\
-	__raw_writel((value), (dev)->regs + WDT_##reg)
-
-struct wdt_at32ap700x {
-	void __iomem		*regs;
-	spinlock_t		io_lock;
-	int			timeout;
-	int			boot_status;
-	unsigned long		users;
-	struct miscdevice	miscdev;
-};
-
-static struct wdt_at32ap700x *wdt;
-static char expect_release;
-
-/*
- * Disable the watchdog.
- */
-static inline void at32_wdt_stop(void)
-{
-	unsigned long psel;
-
-	spin_lock(&wdt->io_lock);
-	psel = wdt_readl(wdt, CTRL) & WDT_BF(CTRL_PSEL, 0x0f);
-	wdt_writel(wdt, CTRL, psel | WDT_BF(CTRL_KEY, 0x55));
-	wdt_writel(wdt, CTRL, psel | WDT_BF(CTRL_KEY, 0xaa));
-	spin_unlock(&wdt->io_lock);
-}
-
-/*
- * Enable and reset the watchdog.
- */
-static inline void at32_wdt_start(void)
-{
-	/* 0xf is 2^16 divider = 2 sec, 0xe is 2^15 divider = 1 sec */
-	unsigned long psel = (wdt->timeout > 1) ? 0xf : 0xe;
-
-	spin_lock(&wdt->io_lock);
-	wdt_writel(wdt, CTRL, WDT_BIT(CTRL_EN)
-			| WDT_BF(CTRL_PSEL, psel)
-			| WDT_BF(CTRL_KEY, 0x55));
-	wdt_writel(wdt, CTRL, WDT_BIT(CTRL_EN)
-			| WDT_BF(CTRL_PSEL, psel)
-			| WDT_BF(CTRL_KEY, 0xaa));
-	spin_unlock(&wdt->io_lock);
-}
-
-/*
- * Pat the watchdog timer.
- */
-static inline void at32_wdt_pat(void)
-{
-	spin_lock(&wdt->io_lock);
-	wdt_writel(wdt, CLR, 0x42);
-	spin_unlock(&wdt->io_lock);
-}
-
-/*
- * Watchdog device is opened, and watchdog starts running.
- */
-static int at32_wdt_open(struct inode *inode, struct file *file)
-{
-	if (test_and_set_bit(1, &wdt->users))
-		return -EBUSY;
-
-	at32_wdt_start();
-	return nonseekable_open(inode, file);
-}
-
-/*
- * Close the watchdog device.
- */
-static int at32_wdt_close(struct inode *inode, struct file *file)
-{
-	if (expect_release == 42) {
-		at32_wdt_stop();
-	} else {
-		dev_dbg(wdt->miscdev.parent,
-			"unexpected close, not stopping watchdog!\n");
-		at32_wdt_pat();
-	}
-	clear_bit(1, &wdt->users);
-	expect_release = 0;
-	return 0;
-}
-
-/*
- * Change the watchdog time interval.
- */
-static int at32_wdt_settimeout(int time)
-{
-	/*
-	 * All counting occurs at 1 / SLOW_CLOCK (32 kHz) and max prescaler is
-	 * 2 ^ 16 allowing up to 2 seconds timeout.
-	 */
-	if ((time < TIMEOUT_MIN) || (time > TIMEOUT_MAX))
-		return -EINVAL;
-
-	/*
-	 * Set new watchdog time. It will be used when at32_wdt_start() is
-	 * called.
-	 */
-	wdt->timeout = time;
-	return 0;
-}
-
-/*
- * Get the watchdog status.
- */
-static int at32_wdt_get_status(void)
-{
-	int rcause;
-	int status = 0;
-
-	rcause = wdt_readl(wdt, RCAUSE);
-
-	switch (rcause) {
-	case WDT_BIT(RCAUSE_EXT):
-		status = WDIOF_EXTERN1;
-		break;
-	case WDT_BIT(RCAUSE_WDT):
-		status = WDIOF_CARDRESET;
-		break;
-	case WDT_BIT(RCAUSE_POR):  /* fall through */
-	case WDT_BIT(RCAUSE_JTAG): /* fall through */
-	case WDT_BIT(RCAUSE_SERP): /* fall through */
-	default:
-		break;
-	}
-
-	return status;
-}
-
-static const struct watchdog_info at32_wdt_info = {
-	.identity	= "at32ap700x watchdog",
-	.options	= WDIOF_SETTIMEOUT |
-			  WDIOF_KEEPALIVEPING |
-			  WDIOF_MAGICCLOSE,
-};
-
-/*
- * Handle commands from user-space.
- */
-static long at32_wdt_ioctl(struct file *file,
-				unsigned int cmd, unsigned long arg)
-{
-	int ret = -ENOTTY;
-	int time;
-	void __user *argp = (void __user *)arg;
-	int __user *p = argp;
-
-	switch (cmd) {
-	case WDIOC_GETSUPPORT:
-		ret = copy_to_user(argp, &at32_wdt_info,
-				sizeof(at32_wdt_info)) ? -EFAULT : 0;
-		break;
-	case WDIOC_GETSTATUS:
-		ret = put_user(0, p);
-		break;
-	case WDIOC_GETBOOTSTATUS:
-		ret = put_user(wdt->boot_status, p);
-		break;
-	case WDIOC_SETOPTIONS:
-		ret = get_user(time, p);
-		if (ret)
-			break;
-		if (time & WDIOS_DISABLECARD)
-			at32_wdt_stop();
-		if (time & WDIOS_ENABLECARD)
-			at32_wdt_start();
-		ret = 0;
-		break;
-	case WDIOC_KEEPALIVE:
-		at32_wdt_pat();
-		ret = 0;
-		break;
-	case WDIOC_SETTIMEOUT:
-		ret = get_user(time, p);
-		if (ret)
-			break;
-		ret = at32_wdt_settimeout(time);
-		if (ret)
-			break;
-		/* Enable new time value */
-		at32_wdt_start();
-		/* fall through */
-	case WDIOC_GETTIMEOUT:
-		ret = put_user(wdt->timeout, p);
-		break;
-	}
-
-	return ret;
-}
-
-static ssize_t at32_wdt_write(struct file *file, const char __user *data,
-				size_t len, loff_t *ppos)
-{
-	/* See if we got the magic character 'V' and reload the timer */
-	if (len) {
-		if (!nowayout) {
-			size_t i;
-
-			/*
-			 * note: just in case someone wrote the magic
-			 * character five months ago...
-			 */
-			expect_release = 0;
-
-			/*
-			 * scan to see whether or not we got the magic
-			 * character
-			 */
-			for (i = 0; i != len; i++) {
-				char c;
-				if (get_user(c, data + i))
-					return -EFAULT;
-				if (c == 'V')
-					expect_release = 42;
-			}
-		}
-		/* someone wrote to us, we should pat the watchdog */
-		at32_wdt_pat();
-	}
-	return len;
-}
-
-static const struct file_operations at32_wdt_fops = {
-	.owner		= THIS_MODULE,
-	.llseek		= no_llseek,
-	.unlocked_ioctl	= at32_wdt_ioctl,
-	.open		= at32_wdt_open,
-	.release	= at32_wdt_close,
-	.write		= at32_wdt_write,
-};
-
-static int __init at32_wdt_probe(struct platform_device *pdev)
-{
-	struct resource	*regs;
-	int ret;
-
-	if (wdt) {
-		dev_dbg(&pdev->dev, "only 1 wdt instance supported.\n");
-		return -EBUSY;
-	}
-
-	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!regs) {
-		dev_dbg(&pdev->dev, "missing mmio resource\n");
-		return -ENXIO;
-	}
-
-	wdt = devm_kzalloc(&pdev->dev, sizeof(struct wdt_at32ap700x),
-			GFP_KERNEL);
-	if (!wdt)
-		return -ENOMEM;
-
-	wdt->regs = devm_ioremap(&pdev->dev, regs->start, resource_size(regs));
-	if (!wdt->regs) {
-		ret = -ENOMEM;
-		dev_dbg(&pdev->dev, "could not map I/O memory\n");
-		goto err_free;
-	}
-
-	spin_lock_init(&wdt->io_lock);
-	wdt->boot_status = at32_wdt_get_status();
-
-	/* Work-around for watchdog silicon errata. */
-	if (wdt->boot_status & WDIOF_CARDRESET) {
-		dev_info(&pdev->dev, "CPU must be reset with external "
-				"reset or POR due to silicon errata.\n");
-		ret = -EIO;
-		goto err_free;
-	} else {
-		wdt->users = 0;
-	}
-
-	wdt->miscdev.minor	= WATCHDOG_MINOR;
-	wdt->miscdev.name	= "watchdog";
-	wdt->miscdev.fops	= &at32_wdt_fops;
-	wdt->miscdev.parent	= &pdev->dev;
-
-	platform_set_drvdata(pdev, wdt);
-
-	if (at32_wdt_settimeout(timeout)) {
-		at32_wdt_settimeout(TIMEOUT_DEFAULT);
-		dev_dbg(&pdev->dev,
-			"default timeout invalid, set to %d sec.\n",
-			TIMEOUT_DEFAULT);
-	}
-
-	ret = misc_register(&wdt->miscdev);
-	if (ret) {
-		dev_dbg(&pdev->dev, "failed to register wdt miscdev\n");
-		goto err_free;
-	}
-
-	dev_info(&pdev->dev,
-		"AT32AP700X WDT at 0x%p, timeout %d sec (nowayout=%d)\n",
-		wdt->regs, wdt->timeout, nowayout);
-
-	return 0;
-
-err_free:
-	wdt = NULL;
-	return ret;
-}
-
-static int __exit at32_wdt_remove(struct platform_device *pdev)
-{
-	if (wdt && platform_get_drvdata(pdev) == wdt) {
-		/* Stop the timer before we leave */
-		if (!nowayout)
-			at32_wdt_stop();
-
-		misc_deregister(&wdt->miscdev);
-		wdt = NULL;
-	}
-	return 0;
-}
-
-static void at32_wdt_shutdown(struct platform_device *pdev)
-{
-	at32_wdt_stop();
-}
-
-#ifdef CONFIG_PM
-static int at32_wdt_suspend(struct platform_device *pdev, pm_message_t message)
-{
-	at32_wdt_stop();
-	return 0;
-}
-
-static int at32_wdt_resume(struct platform_device *pdev)
-{
-	if (wdt->users)
-		at32_wdt_start();
-	return 0;
-}
-#else
-#define at32_wdt_suspend NULL
-#define at32_wdt_resume NULL
-#endif
-
-/* work with hotplug and coldplug */
-MODULE_ALIAS("platform:at32_wdt");
-
-static struct platform_driver at32_wdt_driver = {
-	.remove		= __exit_p(at32_wdt_remove),
-	.suspend	= at32_wdt_suspend,
-	.resume		= at32_wdt_resume,
-	.driver		= {
-		.name	= "at32_wdt",
-	},
-	.shutdown	= at32_wdt_shutdown,
-};
-
-module_platform_driver_probe(at32_wdt_driver, at32_wdt_probe);
-
-MODULE_AUTHOR("Hans-Christian Egtvedt <egtvedt@samfundet.no>");
-MODULE_DESCRIPTION("Watchdog driver for Atmel AT32AP700X");
-MODULE_LICENSE("GPL");

drivers/watchdog/da9062_wdt.c

@@ -46,22 +46,6 @@ static void da9062_set_window_start(struct da9062_watchdog *wdt)
 	wdt->j_time_stamp = jiffies;
 }
 
-static void da9062_apply_window_protection(struct da9062_watchdog *wdt)
-{
-	unsigned long delay = msecs_to_jiffies(DA9062_RESET_PROTECTION_MS);
-	unsigned long timeout = wdt->j_time_stamp + delay;
-	unsigned long now = jiffies;
-	unsigned int diff_ms;
-
-	/* if time-limit has not elapsed then wait for remainder */
-	if (time_before(now, timeout)) {
-		diff_ms = jiffies_to_msecs(timeout-now);
-		dev_dbg(wdt->hw->dev,
-			"Kicked too quickly. Delaying %u msecs\n", diff_ms);
-		msleep(diff_ms);
-	}
-}
-
 static unsigned int da9062_wdt_timeout_to_sel(unsigned int secs)
 {
 	unsigned int i;
@@ -78,8 +62,6 @@ static int da9062_reset_watchdog_timer(struct da9062_watchdog *wdt)
 {
 	int ret;
 
-	da9062_apply_window_protection(wdt);
-
 	ret = regmap_update_bits(wdt->hw->regmap,
 			   DA9062AA_CONTROL_F,
 			   DA9062AA_WATCHDOG_MASK,
@@ -100,6 +82,13 @@ static int da9062_wdt_update_timeout_register(struct da9062_watchdog *wdt,
 	if (ret)
 		return ret;
 
+	regmap_update_bits(chip->regmap,
+				  DA9062AA_CONTROL_D,
+				  DA9062AA_TWDSCALE_MASK,
+				  DA9062_TWDSCALE_DISABLE);
+
+	usleep_range(150, 300);
+
 	return regmap_update_bits(chip->regmap,
 				  DA9062AA_CONTROL_D,
 				  DA9062AA_TWDSCALE_MASK,
@@ -175,6 +164,25 @@ static int da9062_wdt_set_timeout(struct watchdog_device *wdd,
 	return ret;
 }
 
+static int da9062_wdt_restart(struct watchdog_device *wdd, unsigned long action,
+			      void *data)
+{
+	struct da9062_watchdog *wdt = watchdog_get_drvdata(wdd);
+	int ret;
+
+	ret = regmap_write(wdt->hw->regmap,
+			   DA9062AA_CONTROL_F,
+			   DA9062AA_SHUTDOWN_MASK);
+	if (ret)
+		dev_alert(wdt->hw->dev, "Failed to shutdown (err = %d)\n",
+			  ret);
+
+	/* wait for reset to assert... */
+	mdelay(500);
+
+	return ret;
+}
+
 static const struct watchdog_info da9062_watchdog_info = {
 	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
 	.identity = "DA9062 WDT",
@@ -186,6 +194,7 @@ static const struct watchdog_ops da9062_watchdog_ops = {
 	.stop = da9062_wdt_stop,
 	.ping = da9062_wdt_ping,
 	.set_timeout = da9062_wdt_set_timeout,
+	.restart = da9062_wdt_restart,
 };
 
 static const struct of_device_id da9062_compatible_id_table[] = {
@@ -215,10 +224,13 @@ static int da9062_wdt_probe(struct platform_device *pdev)
 	wdt->wdtdev.ops = &da9062_watchdog_ops;
 	wdt->wdtdev.min_timeout = DA9062_WDT_MIN_TIMEOUT;
 	wdt->wdtdev.max_timeout = DA9062_WDT_MAX_TIMEOUT;
+	wdt->wdtdev.min_hw_heartbeat_ms = DA9062_RESET_PROTECTION_MS;
 	wdt->wdtdev.timeout = DA9062_WDG_DEFAULT_TIMEOUT;
 	wdt->wdtdev.status = WATCHDOG_NOWAYOUT_INIT_STATUS;
 	wdt->wdtdev.parent = &pdev->dev;
 
+	watchdog_set_restart_priority(&wdt->wdtdev, 128);
+
 	watchdog_set_drvdata(&wdt->wdtdev, wdt);
 
 	ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdtdev);

drivers/watchdog/davinci_wdt.c

@@ -140,6 +140,42 @@ static unsigned int davinci_wdt_get_timeleft(struct watchdog_device *wdd)
 	return wdd->timeout - timer_counter;
 }
 
+static int davinci_wdt_restart(struct watchdog_device *wdd,
+			       unsigned long action, void *data)
+{
+	struct davinci_wdt_device *davinci_wdt = watchdog_get_drvdata(wdd);
+	u32 tgcr, wdtcr;
+
+	/* disable, internal clock source */
+	iowrite32(0, davinci_wdt->base + TCR);
+
+	/* reset timer, set mode to 64-bit watchdog, and unreset */
+	tgcr = 0;
+	iowrite32(tgcr, davinci_wdt->base + TGCR);
+	tgcr = TIMMODE_64BIT_WDOG | TIM12RS_UNRESET | TIM34RS_UNRESET;
+	iowrite32(tgcr, davinci_wdt->base + TGCR);
+
+	/* clear counter and period regs */
+	iowrite32(0, davinci_wdt->base + TIM12);
+	iowrite32(0, davinci_wdt->base + TIM34);
+	iowrite32(0, davinci_wdt->base + PRD12);
+	iowrite32(0, davinci_wdt->base + PRD34);
+
+	/* put watchdog in pre-active state */
+	wdtcr = WDKEY_SEQ0 | WDEN;
+	iowrite32(wdtcr, davinci_wdt->base + WDTCR);
+
+	/* put watchdog in active state */
+	wdtcr = WDKEY_SEQ1 | WDEN;
+	iowrite32(wdtcr, davinci_wdt->base + WDTCR);
+
+	/* write an invalid value to the WDKEY field to trigger a restart */
+	wdtcr = 0x00004000;
+	iowrite32(wdtcr, davinci_wdt->base + WDTCR);
+
+	return 0;
+}
+
 static const struct watchdog_info davinci_wdt_info = {
 	.options = WDIOF_KEEPALIVEPING,
 	.identity = "DaVinci/Keystone Watchdog",
@@ -151,6 +187,7 @@ static const struct watchdog_ops davinci_wdt_ops = {
 	.stop		= davinci_wdt_ping,
 	.ping		= davinci_wdt_ping,
 	.get_timeleft	= davinci_wdt_get_timeleft,
+	.restart	= davinci_wdt_restart,
 };
 
 static int davinci_wdt_probe(struct platform_device *pdev)
@@ -195,6 +232,7 @@ static int davinci_wdt_probe(struct platform_device *pdev)
 
 	watchdog_set_drvdata(wdd, davinci_wdt);
 	watchdog_set_nowayout(wdd, 1);
+	watchdog_set_restart_priority(wdd, 128);
 
 	wdt_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	davinci_wdt->base = devm_ioremap_resource(dev, wdt_mem);

drivers/watchdog/dw_wdt.c

@@ -127,14 +127,27 @@ static int dw_wdt_start(struct watchdog_device *wdd)
 
 	dw_wdt_set_timeout(wdd, wdd->timeout);
 
-	set_bit(WDOG_HW_RUNNING, &wdd->status);
-
 	writel(WDOG_CONTROL_REG_WDT_EN_MASK,
 	       dw_wdt->regs + WDOG_CONTROL_REG_OFFSET);
 
 	return 0;
 }
 
+static int dw_wdt_stop(struct watchdog_device *wdd)
+{
+	struct dw_wdt *dw_wdt = to_dw_wdt(wdd);
+
+	if (!dw_wdt->rst) {
+		set_bit(WDOG_HW_RUNNING, &wdd->status);
+		return 0;
+	}
+
+	reset_control_assert(dw_wdt->rst);
+	reset_control_deassert(dw_wdt->rst);
+
+	return 0;
+}
+
 static int dw_wdt_restart(struct watchdog_device *wdd,
 			  unsigned long action, void *data)
 {
@@ -173,6 +186,7 @@ static const struct watchdog_info dw_wdt_ident = {
 static const struct watchdog_ops dw_wdt_ops = {
 	.owner		= THIS_MODULE,
 	.start		= dw_wdt_start,
+	.stop		= dw_wdt_stop,
 	.ping		= dw_wdt_ping,
 	.set_timeout	= dw_wdt_set_timeout,
 	.get_timeleft	= dw_wdt_get_timeleft,

drivers/watchdog/eurotechwdt.c

@@ -290,7 +290,7 @@ static long eurwdt_ioctl(struct file *file,
 		eurwdt_timeout = time;
 		eurwdt_set_timeout(time);
 		spin_unlock(&eurwdt_lock);
-		/* Fall */
+		/* fall through */
 
 	case WDIOC_GETTIMEOUT:
 		return put_user(eurwdt_timeout, p);

drivers/watchdog/f71808e_wdt.c

@@ -627,7 +627,7 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd,
 
 		if (new_options & WDIOS_ENABLECARD)
 			return watchdog_start();
-
+		/* fall through */
 
 	case WDIOC_KEEPALIVE:
 		watchdog_keepalive();
@@ -641,7 +641,7 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd,
 			return -EINVAL;
 
 		watchdog_keepalive();
-		/* Fall */
+		/* fall through */
 
 	case WDIOC_GETTIMEOUT:
 		return put_user(watchdog.timeout, uarg.i);

drivers/watchdog/gemini_wdt.c → drivers/watchdog/ftwdt010_wdt.c

 /*
- * Watchdog driver for Cortina Systems Gemini SoC
+ * Watchdog driver for Faraday Technology FTWDT010
  *
  * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
  *
@@ -22,92 +22,98 @@
 #include <linux/slab.h>
 #include <linux/watchdog.h>
 
-#define GEMINI_WDCOUNTER	0x0
-#define GEMINI_WDLOAD		0x4
-#define GEMINI_WDRESTART	0x8
-#define GEMINI_WDCR		0xC
+#define FTWDT010_WDCOUNTER	0x0
+#define FTWDT010_WDLOAD		0x4
+#define FTWDT010_WDRESTART	0x8
+#define FTWDT010_WDCR		0xC
 
 #define WDRESTART_MAGIC		0x5AB9
 
 #define WDCR_CLOCK_5MHZ		BIT(4)
+#define WDCR_WDEXT		BIT(3)
+#define WDCR_WDINTR		BIT(2)
 #define WDCR_SYS_RST		BIT(1)
 #define WDCR_ENABLE		BIT(0)
 
 #define WDT_CLOCK		5000000		/* 5 MHz */
 
-struct gemini_wdt {
+struct ftwdt010_wdt {
 	struct watchdog_device	wdd;
 	struct device		*dev;
 	void __iomem		*base;
+	bool			has_irq;
 };
 
 static inline
-struct gemini_wdt *to_gemini_wdt(struct watchdog_device *wdd)
+struct ftwdt010_wdt *to_ftwdt010_wdt(struct watchdog_device *wdd)
 {
-	return container_of(wdd, struct gemini_wdt, wdd);
+	return container_of(wdd, struct ftwdt010_wdt, wdd);
 }
 
-static int gemini_wdt_start(struct watchdog_device *wdd)
+static int ftwdt010_wdt_start(struct watchdog_device *wdd)
 {
-	struct gemini_wdt *gwdt = to_gemini_wdt(wdd);
+	struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd);
+	u32 enable;
 
-	writel(wdd->timeout * WDT_CLOCK, gwdt->base + GEMINI_WDLOAD);
-	writel(WDRESTART_MAGIC, gwdt->base + GEMINI_WDRESTART);
+	writel(wdd->timeout * WDT_CLOCK, gwdt->base + FTWDT010_WDLOAD);
+	writel(WDRESTART_MAGIC, gwdt->base + FTWDT010_WDRESTART);
 	/* set clock before enabling */
-	writel(WDCR_CLOCK_5MHZ | WDCR_SYS_RST,
-			gwdt->base + GEMINI_WDCR);
-	writel(WDCR_CLOCK_5MHZ | WDCR_SYS_RST | WDCR_ENABLE,
-			gwdt->base + GEMINI_WDCR);
+	enable = WDCR_CLOCK_5MHZ | WDCR_SYS_RST;
+	writel(enable, gwdt->base + FTWDT010_WDCR);
+	if (gwdt->has_irq)
+		enable |= WDCR_WDINTR;
+	enable |= WDCR_ENABLE;
+	writel(enable, gwdt->base + FTWDT010_WDCR);
 
 	return 0;
 }
 
-static int gemini_wdt_stop(struct watchdog_device *wdd)
+static int ftwdt010_wdt_stop(struct watchdog_device *wdd)
 {
-	struct gemini_wdt *gwdt = to_gemini_wdt(wdd);
+	struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd);
 
-	writel(0, gwdt->base + GEMINI_WDCR);
+	writel(0, gwdt->base + FTWDT010_WDCR);
 
 	return 0;
 }
 
-static int gemini_wdt_ping(struct watchdog_device *wdd)
+static int ftwdt010_wdt_ping(struct watchdog_device *wdd)
 {
-	struct gemini_wdt *gwdt = to_gemini_wdt(wdd);
+	struct ftwdt010_wdt *gwdt = to_ftwdt010_wdt(wdd);
 
-	writel(WDRESTART_MAGIC, gwdt->base + GEMINI_WDRESTART);
+	writel(WDRESTART_MAGIC, gwdt->base + FTWDT010_WDRESTART);
 
 	return 0;
 }
 
-static int gemini_wdt_set_timeout(struct watchdog_device *wdd,
+static int ftwdt010_wdt_set_timeout(struct watchdog_device *wdd,
 				  unsigned int timeout)
 {
 	wdd->timeout = timeout;
 	if (watchdog_active(wdd))
-		gemini_wdt_start(wdd);
+		ftwdt010_wdt_start(wdd);
 
 	return 0;
 }
 
-static irqreturn_t gemini_wdt_interrupt(int irq, void *data)
+static irqreturn_t ftwdt010_wdt_interrupt(int irq, void *data)
 {
-	struct gemini_wdt *gwdt = data;
+	struct ftwdt010_wdt *gwdt = data;
 
 	watchdog_notify_pretimeout(&gwdt->wdd);
 
 	return IRQ_HANDLED;
 }
 
-static const struct watchdog_ops gemini_wdt_ops = {
-	.start		= gemini_wdt_start,
-	.stop		= gemini_wdt_stop,
-	.ping		= gemini_wdt_ping,
-	.set_timeout	= gemini_wdt_set_timeout,
+static const struct watchdog_ops ftwdt010_wdt_ops = {
+	.start		= ftwdt010_wdt_start,
+	.stop		= ftwdt010_wdt_stop,
+	.ping		= ftwdt010_wdt_ping,
+	.set_timeout	= ftwdt010_wdt_set_timeout,
 	.owner		= THIS_MODULE,
 };
 
-static const struct watchdog_info gemini_wdt_info = {
+static const struct watchdog_info ftwdt010_wdt_info = {
 	.options	= WDIOF_KEEPALIVEPING
 			| WDIOF_MAGICCLOSE
 			| WDIOF_SETTIMEOUT,
@@ -115,11 +121,11 @@ static const struct watchdog_info gemini_wdt_info = {
 };
 
 
-static int gemini_wdt_probe(struct platform_device *pdev)
+static int ftwdt010_wdt_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	struct resource *res;
-	struct gemini_wdt *gwdt;
+	struct ftwdt010_wdt *gwdt;
 	unsigned int reg;
 	int irq;
 	int ret;
@@ -133,13 +139,9 @@ static int gemini_wdt_probe(struct platform_device *pdev)
 	if (IS_ERR(gwdt->base))
 		return PTR_ERR(gwdt->base);
 
-	irq = platform_get_irq(pdev, 0);
-	if (!irq)
-		return -EINVAL;
-
 	gwdt->dev = dev;
-	gwdt->wdd.info = &gemini_wdt_info;
-	gwdt->wdd.ops = &gemini_wdt_ops;
+	gwdt->wdd.info = &ftwdt010_wdt_info;
+	gwdt->wdd.ops = &ftwdt010_wdt_ops;
 	gwdt->wdd.min_timeout = 1;
 	gwdt->wdd.max_timeout = 0xFFFFFFFF / WDT_CLOCK;
 	gwdt->wdd.parent = dev;
@@ -151,17 +153,21 @@ static int gemini_wdt_probe(struct platform_device *pdev)
 	gwdt->wdd.timeout = 13U;
 	watchdog_init_timeout(&gwdt->wdd, 0, dev);
 
-	reg = readw(gwdt->base + GEMINI_WDCR);
+	reg = readw(gwdt->base + FTWDT010_WDCR);
 	if (reg & WDCR_ENABLE) {
 		/* Watchdog was enabled by the bootloader, disable it. */
 		reg &= ~WDCR_ENABLE;
-		writel(reg, gwdt->base + GEMINI_WDCR);
+		writel(reg, gwdt->base + FTWDT010_WDCR);
 	}
 
-	ret = devm_request_irq(dev, irq, gemini_wdt_interrupt, 0,
-			       "watchdog bark", gwdt);
-	if (ret)
-		return ret;
+	irq = platform_get_irq(pdev, 0);
+	if (irq) {
+		ret = devm_request_irq(dev, irq, ftwdt010_wdt_interrupt, 0,
+				       "watchdog bark", gwdt);
+		if (ret)
+			return ret;
+		gwdt->has_irq = true;
+	}
 
 	ret = devm_watchdog_register_device(dev, &gwdt->wdd);
 	if (ret) {
@@ -171,59 +177,60 @@ static int gemini_wdt_probe(struct platform_device *pdev)
 
 	/* Set up platform driver data */
 	platform_set_drvdata(pdev, gwdt);
-	dev_info(dev, "Gemini watchdog driver enabled\n");
+	dev_info(dev, "FTWDT010 watchdog driver enabled\n");
 
 	return 0;
 }
 
-static int __maybe_unused gemini_wdt_suspend(struct device *dev)
+static int __maybe_unused ftwdt010_wdt_suspend(struct device *dev)
 {
-	struct gemini_wdt *gwdt = dev_get_drvdata(dev);
+	struct ftwdt010_wdt *gwdt = dev_get_drvdata(dev);
 	unsigned int reg;
 
-	reg = readw(gwdt->base + GEMINI_WDCR);
+	reg = readw(gwdt->base + FTWDT010_WDCR);
 	reg &= ~WDCR_ENABLE;
-	writel(reg, gwdt->base + GEMINI_WDCR);
+	writel(reg, gwdt->base + FTWDT010_WDCR);
 
 	return 0;
 }
 
-static int __maybe_unused gemini_wdt_resume(struct device *dev)
+static int __maybe_unused ftwdt010_wdt_resume(struct device *dev)
 {
-	struct gemini_wdt *gwdt = dev_get_drvdata(dev);
+	struct ftwdt010_wdt *gwdt = dev_get_drvdata(dev);
 	unsigned int reg;
 
 	if (watchdog_active(&gwdt->wdd)) {
-		reg = readw(gwdt->base + GEMINI_WDCR);
+		reg = readw(gwdt->base + FTWDT010_WDCR);
 		reg |= WDCR_ENABLE;
-		writel(reg, gwdt->base + GEMINI_WDCR);
+		writel(reg, gwdt->base + FTWDT010_WDCR);
 	}
 
 	return 0;
 }
 
-static const struct dev_pm_ops gemini_wdt_dev_pm_ops = {
-	SET_SYSTEM_SLEEP_PM_OPS(gemini_wdt_suspend,
-				gemini_wdt_resume)
+static const struct dev_pm_ops ftwdt010_wdt_dev_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(ftwdt010_wdt_suspend,
+				ftwdt010_wdt_resume)
 };
 
 #ifdef CONFIG_OF
-static const struct of_device_id gemini_wdt_match[] = {
+static const struct of_device_id ftwdt010_wdt_match[] = {
+	{ .compatible = "faraday,ftwdt010" },
 	{ .compatible = "cortina,gemini-watchdog" },
 	{},
 };
-MODULE_DEVICE_TABLE(of, gemini_wdt_match);
+MODULE_DEVICE_TABLE(of, ftwdt010_wdt_match);
 #endif
 
-static struct platform_driver gemini_wdt_driver = {
-	.probe		= gemini_wdt_probe,
+static struct platform_driver ftwdt010_wdt_driver = {
+	.probe		= ftwdt010_wdt_probe,
 	.driver		= {
-		.name	= "gemini-wdt",
-		.of_match_table = of_match_ptr(gemini_wdt_match),
-		.pm = &gemini_wdt_dev_pm_ops,
+		.name	= "ftwdt010-wdt",
+		.of_match_table = of_match_ptr(ftwdt010_wdt_match),
+		.pm = &ftwdt010_wdt_dev_pm_ops,
 	},
 };
-module_platform_driver(gemini_wdt_driver);
+module_platform_driver(ftwdt010_wdt_driver);
 MODULE_AUTHOR("Linus Walleij");
-MODULE_DESCRIPTION("Watchdog driver for Gemini");
+MODULE_DESCRIPTION("Watchdog driver for Faraday Technology FTWDT010");
 MODULE_LICENSE("GPL");

drivers/watchdog/gpio_wdt.c

@@ -12,7 +12,8 @@
 #include <linux/err.h>
 #include <linux/delay.h>
 #include <linux/module.h>
-#include <linux/of_gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/watchdog.h>
 
@@ -25,8 +26,7 @@ enum {
 };
 
 struct gpio_wdt_priv {
-	int			gpio;
-	bool			active_low;
+	struct gpio_desc	*gpiod;
 	bool			state;
 	bool			always_running;
 	unsigned int		hw_algo;
@@ -35,11 +35,12 @@ struct gpio_wdt_priv {
 
 static void gpio_wdt_disable(struct gpio_wdt_priv *priv)
 {
-	gpio_set_value_cansleep(priv->gpio, !priv->active_low);
+	/* Eternal ping */
+	gpiod_set_value_cansleep(priv->gpiod, 1);
 
 	/* Put GPIO back to tristate */
 	if (priv->hw_algo == HW_ALGO_TOGGLE)
-		gpio_direction_input(priv->gpio);
+		gpiod_direction_input(priv->gpiod);
 }
 
 static int gpio_wdt_ping(struct watchdog_device *wdd)
@@ -50,13 +51,13 @@ static int gpio_wdt_ping(struct watchdog_device *wdd)
 	case HW_ALGO_TOGGLE:
 		/* Toggle output pin */
 		priv->state = !priv->state;
-		gpio_set_value_cansleep(priv->gpio, priv->state);
+		gpiod_set_value_cansleep(priv->gpiod, priv->state);
 		break;
 	case HW_ALGO_LEVEL:
 		/* Pulse */
-		gpio_set_value_cansleep(priv->gpio, !priv->active_low);
+		gpiod_set_value_cansleep(priv->gpiod, 1);
 		udelay(1);
-		gpio_set_value_cansleep(priv->gpio, priv->active_low);
+		gpiod_set_value_cansleep(priv->gpiod, 0);
 		break;
 	}
 	return 0;
@@ -66,8 +67,8 @@ static int gpio_wdt_start(struct watchdog_device *wdd)
 {
 	struct gpio_wdt_priv *priv = watchdog_get_drvdata(wdd);
 
-	priv->state = priv->active_low;
-	gpio_direction_output(priv->gpio, priv->state);
+	priv->state = 0;
+	gpiod_direction_output(priv->gpiod, priv->state);
 
 	set_bit(WDOG_HW_RUNNING, &wdd->status);
 
@@ -80,7 +81,8 @@ static int gpio_wdt_stop(struct watchdog_device *wdd)
 
 	if (!priv->always_running) {
 		gpio_wdt_disable(priv);
-		clear_bit(WDOG_HW_RUNNING, &wdd->status);
+	} else {
+		set_bit(WDOG_HW_RUNNING, &wdd->status);
 	}
 
 	return 0;
@@ -101,44 +103,38 @@ static const struct watchdog_ops gpio_wdt_ops = {
 
 static int gpio_wdt_probe(struct platform_device *pdev)
 {
+	struct device *dev = &pdev->dev;
+	struct device_node *np = dev->of_node;
 	struct gpio_wdt_priv *priv;
-	enum of_gpio_flags flags;
+	enum gpiod_flags gflags;
 	unsigned int hw_margin;
-	unsigned long f = 0;
 	const char *algo;
 	int ret;
 
-	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
 	platform_set_drvdata(pdev, priv);
 
-	priv->gpio = of_get_gpio_flags(pdev->dev.of_node, 0, &flags);
-	if (!gpio_is_valid(priv->gpio))
-		return priv->gpio;
-
-	priv->active_low = flags & OF_GPIO_ACTIVE_LOW;
-
-	ret = of_property_read_string(pdev->dev.of_node, "hw_algo", &algo);
+	ret = of_property_read_string(np, "hw_algo", &algo);
 	if (ret)
 		return ret;
 	if (!strcmp(algo, "toggle")) {
 		priv->hw_algo = HW_ALGO_TOGGLE;
-		f = GPIOF_IN;
+		gflags = GPIOD_IN;
 	} else if (!strcmp(algo, "level")) {
 		priv->hw_algo = HW_ALGO_LEVEL;
-		f = priv->active_low ? GPIOF_OUT_INIT_HIGH : GPIOF_OUT_INIT_LOW;
+		gflags = GPIOD_OUT_LOW;
 	} else {
 		return -EINVAL;
 	}
 
-	ret = devm_gpio_request_one(&pdev->dev, priv->gpio, f,
-				    dev_name(&pdev->dev));
-	if (ret)
-		return ret;
+	priv->gpiod = devm_gpiod_get(dev, NULL, gflags);
+	if (IS_ERR(priv->gpiod))
+		return PTR_ERR(priv->gpiod);
 
-	ret = of_property_read_u32(pdev->dev.of_node,
+	ret = of_property_read_u32(np,
 				   "hw_margin_ms", &hw_margin);
 	if (ret)
 		return ret;
@@ -146,7 +142,7 @@ static int gpio_wdt_probe(struct platform_device *pdev)
 	if (hw_margin < 2 || hw_margin > 65535)
 		return -EINVAL;
 
-	priv->always_running = of_property_read_bool(pdev->dev.of_node,
+	priv->always_running = of_property_read_bool(np,
 						     "always-running");
 
 	watchdog_set_drvdata(&priv->wdd, priv);
@@ -155,9 +151,9 @@ static int gpio_wdt_probe(struct platform_device *pdev)
 	priv->wdd.ops		= &gpio_wdt_ops;
 	priv->wdd.min_timeout	= SOFT_TIMEOUT_MIN;
 	priv->wdd.max_hw_heartbeat_ms = hw_margin;
-	priv->wdd.parent	= &pdev->dev;
+	priv->wdd.parent	= dev;
 
-	if (watchdog_init_timeout(&priv->wdd, 0, &pdev->dev) < 0)
+	if (watchdog_init_timeout(&priv->wdd, 0, dev) < 0)
 		priv->wdd.timeout = SOFT_TIMEOUT_DEF;
 
 	watchdog_stop_on_reboot(&priv->wdd);

drivers/watchdog/hpwdt.c

@@ -52,6 +52,7 @@ static char expect_release;
 static unsigned long hpwdt_is_open;
 
 static void __iomem *pci_mem_addr;		/* the PCI-memory address */
+static unsigned long __iomem *hpwdt_nmistat;
 static unsigned long __iomem *hpwdt_timer_reg;
 static unsigned long __iomem *hpwdt_timer_con;
 
@@ -475,6 +476,11 @@ static int hpwdt_time_left(void)
 }
 
 #ifdef CONFIG_HPWDT_NMI_DECODING
+static int hpwdt_my_nmi(void)
+{
+	return ioread8(hpwdt_nmistat) & 0x6;
+}
+
 /*
  *	NMI Handler
  */
@@ -486,6 +492,9 @@ static int hpwdt_pretimeout(unsigned int ulReason, struct pt_regs *regs)
 	if (!hpwdt_nmi_decoding)
 		return NMI_DONE;
 
+	if ((ulReason == NMI_UNKNOWN) && !hpwdt_my_nmi())
+		return NMI_DONE;
+
 	spin_lock_irqsave(&rom_lock, rom_pl);
 	if (!die_nmi_called && !is_icru && !is_uefi)
 		asminline_call(&cmn_regs, cru_rom_addr);
@@ -700,7 +709,7 @@ static void dmi_find_icru(const struct dmi_header *dm, void *dummy)
 		smbios_proliant_ptr = (struct smbios_proliant_info *) dm;
 		if (smbios_proliant_ptr->misc_features & 0x01)
 			is_icru = 1;
-		if (smbios_proliant_ptr->misc_features & 0x408)
+		if (smbios_proliant_ptr->misc_features & 0x1400)
 			is_uefi = 1;
 	}
 }
@@ -842,6 +851,7 @@ static int hpwdt_init_one(struct pci_dev *dev,
 		retval = -ENOMEM;
 		goto error_pci_iomap;
 	}
+	hpwdt_nmistat	= pci_mem_addr + 0x6e;
 	hpwdt_timer_reg = pci_mem_addr + 0x70;
 	hpwdt_timer_con = pci_mem_addr + 0x72;
 

drivers/watchdog/i6300esb.c

@@ -21,14 +21,15 @@
  *	Version 0.02
  *  20050210 David Härdeman <david@2gen.com>
  *	Ported driver to kernel 2.6
+ *  20171016 Radu Rendec <rrendec@arista.com>
+ *	Change driver to use the watchdog subsystem
+ *	Add support for multiple 6300ESB devices
  */
 
 /*
  *      Includes, defines, variables, module parameters, ...
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/kernel.h>
@@ -42,19 +43,17 @@
 #include <linux/io.h>
 
 /* Module and version information */
-#define ESB_VERSION "0.05"
 #define ESB_MODULE_NAME "i6300ESB timer"
-#define ESB_DRIVER_NAME ESB_MODULE_NAME ", v" ESB_VERSION
 
 /* PCI configuration registers */
 #define ESB_CONFIG_REG  0x60            /* Config register                   */
 #define ESB_LOCK_REG    0x68            /* WDT lock register                 */
 
 /* Memory mapped registers */
-#define ESB_TIMER1_REG (BASEADDR + 0x00)/* Timer1 value after each reset     */
-#define ESB_TIMER2_REG (BASEADDR + 0x04)/* Timer2 value after each reset     */
-#define ESB_GINTSR_REG (BASEADDR + 0x08)/* General Interrupt Status Register */
-#define ESB_RELOAD_REG (BASEADDR + 0x0c)/* Reload register                   */
+#define ESB_TIMER1_REG(w) ((w)->base + 0x00)/* Timer1 value after each reset */
+#define ESB_TIMER2_REG(w) ((w)->base + 0x04)/* Timer2 value after each reset */
+#define ESB_GINTSR_REG(w) ((w)->base + 0x08)/* General Interrupt Status Reg  */
+#define ESB_RELOAD_REG(w) ((w)->base + 0x0c)/* Reload register               */
 
 /* Lock register bits */
 #define ESB_WDT_FUNC    (0x01 << 2)   /* Watchdog functionality            */
@@ -74,25 +73,18 @@
 #define ESB_UNLOCK1     0x80            /* Step 1 to unlock reset registers  */
 #define ESB_UNLOCK2     0x86            /* Step 2 to unlock reset registers  */
 
-/* internal variables */
-static void __iomem *BASEADDR;
-static DEFINE_SPINLOCK(esb_lock); /* Guards the hardware */
-static unsigned long timer_alive;
-static struct pci_dev *esb_pci;
-static unsigned short triggered; /* The status of the watchdog upon boot */
-static char esb_expect_close;
-
-/* We can only use 1 card due to the /dev/watchdog restriction */
-static int cards_found;
-
 /* module parameters */
 /* 30 sec default heartbeat (1 < heartbeat < 2*1023) */
-#define WATCHDOG_HEARTBEAT 30
-static int heartbeat = WATCHDOG_HEARTBEAT;  /* in seconds */
+#define ESB_HEARTBEAT_MIN	1
+#define ESB_HEARTBEAT_MAX	2046
+#define ESB_HEARTBEAT_DEFAULT	30
+#define ESB_HEARTBEAT_RANGE __MODULE_STRING(ESB_HEARTBEAT_MIN) \
+	"<heartbeat<" __MODULE_STRING(ESB_HEARTBEAT_MAX)
+static int heartbeat; /* in seconds */
 module_param(heartbeat, int, 0);
 MODULE_PARM_DESC(heartbeat,
-		"Watchdog heartbeat in seconds. (1<heartbeat<2046, default="
-				__MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
+	"Watchdog heartbeat in seconds. (" ESB_HEARTBEAT_RANGE
+	", default=" __MODULE_STRING(ESB_HEARTBEAT_DEFAULT) ")");
 
 static bool nowayout = WATCHDOG_NOWAYOUT;
 module_param(nowayout, bool, 0);
@@ -100,6 +92,15 @@ MODULE_PARM_DESC(nowayout,
 		"Watchdog cannot be stopped once started (default="
 				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
+/* internal variables */
+struct esb_dev {
+	struct watchdog_device wdd;
+	void __iomem *base;
+	struct pci_dev *pdev;
+};
+
+#define to_esb_dev(wptr) container_of(wptr, struct esb_dev, wdd)
+
 /*
  * Some i6300ESB specific functions
  */
@@ -110,61 +111,58 @@ MODULE_PARM_DESC(nowayout,
  * reload register. After this the appropriate registers can be written
  * to once before they need to be unlocked again.
  */
-static inline void esb_unlock_registers(void)
+static inline void esb_unlock_registers(struct esb_dev *edev)
 {
-	writew(ESB_UNLOCK1, ESB_RELOAD_REG);
-	writew(ESB_UNLOCK2, ESB_RELOAD_REG);
+	writew(ESB_UNLOCK1, ESB_RELOAD_REG(edev));
+	writew(ESB_UNLOCK2, ESB_RELOAD_REG(edev));
 }
 
-static int esb_timer_start(void)
+static int esb_timer_start(struct watchdog_device *wdd)
 {
+	struct esb_dev *edev = to_esb_dev(wdd);
+	int _wdd_nowayout = test_bit(WDOG_NO_WAY_OUT, &wdd->status);
 	u8 val;
 
-	spin_lock(&esb_lock);
-	esb_unlock_registers();
-	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
+	esb_unlock_registers(edev);
+	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
 	/* Enable or Enable + Lock? */
-	val = ESB_WDT_ENABLE | (nowayout ? ESB_WDT_LOCK : 0x00);
-	pci_write_config_byte(esb_pci, ESB_LOCK_REG, val);
-	spin_unlock(&esb_lock);
+	val = ESB_WDT_ENABLE | (_wdd_nowayout ? ESB_WDT_LOCK : 0x00);
+	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, val);
 	return 0;
 }
 
-static int esb_timer_stop(void)
+static int esb_timer_stop(struct watchdog_device *wdd)
 {
+	struct esb_dev *edev = to_esb_dev(wdd);
 	u8 val;
 
-	spin_lock(&esb_lock);
 	/* First, reset timers as suggested by the docs */
-	esb_unlock_registers();
-	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
+	esb_unlock_registers(edev);
+	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
 	/* Then disable the WDT */
-	pci_write_config_byte(esb_pci, ESB_LOCK_REG, 0x0);
-	pci_read_config_byte(esb_pci, ESB_LOCK_REG, &val);
-	spin_unlock(&esb_lock);
+	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x0);
+	pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val);
 
 	/* Returns 0 if the timer was disabled, non-zero otherwise */
 	return val & ESB_WDT_ENABLE;
 }
 
-static void esb_timer_keepalive(void)
+static int esb_timer_keepalive(struct watchdog_device *wdd)
 {
-	spin_lock(&esb_lock);
-	esb_unlock_registers();
-	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
+	struct esb_dev *edev = to_esb_dev(wdd);
+
+	esb_unlock_registers(edev);
+	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
 	/* FIXME: Do we need to flush anything here? */
-	spin_unlock(&esb_lock);
+	return 0;
 }
 
-static int esb_timer_set_heartbeat(int time)
+static int esb_timer_set_heartbeat(struct watchdog_device *wdd,
+		unsigned int time)
 {
+	struct esb_dev *edev = to_esb_dev(wdd);
 	u32 val;
 
-	if (time < 0x1 || time > (2 * 0x03ff))
-		return -EINVAL;
-
-	spin_lock(&esb_lock);
-
 	/* We shift by 9, so if we are passed a value of 1 sec,
 	 * val will be 1 << 9 = 512, then write that to two
 	 * timers => 2 * 512 = 1024 (which is decremented at 1KHz)
@@ -172,162 +170,39 @@ static int esb_timer_set_heartbeat(int time)
 	val = time << 9;
 
 	/* Write timer 1 */
-	esb_unlock_registers();
-	writel(val, ESB_TIMER1_REG);
+	esb_unlock_registers(edev);
+	writel(val, ESB_TIMER1_REG(edev));
 
 	/* Write timer 2 */
-	esb_unlock_registers();
-	writel(val, ESB_TIMER2_REG);
+	esb_unlock_registers(edev);
+	writel(val, ESB_TIMER2_REG(edev));
 
 	/* Reload */
-	esb_unlock_registers();
-	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG);
+	esb_unlock_registers(edev);
+	writew(ESB_WDT_RELOAD, ESB_RELOAD_REG(edev));
 
 	/* FIXME: Do we need to flush everything out? */
 
 	/* Done */
-	heartbeat = time;
-	spin_unlock(&esb_lock);
-	return 0;
-}
-
-/*
- *	/dev/watchdog handling
- */
-
-static int esb_open(struct inode *inode, struct file *file)
-{
-	/* /dev/watchdog can only be opened once */
-	if (test_and_set_bit(0, &timer_alive))
-		return -EBUSY;
-
-	/* Reload and activate timer */
-	esb_timer_start();
-
-	return nonseekable_open(inode, file);
-}
-
-static int esb_release(struct inode *inode, struct file *file)
-{
-	/* Shut off the timer. */
-	if (esb_expect_close == 42)
-		esb_timer_stop();
-	else {
-		pr_crit("Unexpected close, not stopping watchdog!\n");
-		esb_timer_keepalive();
-	}
-	clear_bit(0, &timer_alive);
-	esb_expect_close = 0;
+	wdd->timeout = time;
 	return 0;
 }
 
-static ssize_t esb_write(struct file *file, const char __user *data,
-			  size_t len, loff_t *ppos)
-{
-	/* See if we got the magic character 'V' and reload the timer */
-	if (len) {
-		if (!nowayout) {
-			size_t i;
-
-			/* note: just in case someone wrote the magic character
-			 * five months ago... */
-			esb_expect_close = 0;
-
-			/* scan to see whether or not we got the
-			 * magic character */
-			for (i = 0; i != len; i++) {
-				char c;
-				if (get_user(c, data + i))
-					return -EFAULT;
-				if (c == 'V')
-					esb_expect_close = 42;
-			}
-		}
-
-		/* someone wrote to us, we should reload the timer */
-		esb_timer_keepalive();
-	}
-	return len;
-}
-
-static long esb_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
-	int new_options, retval = -EINVAL;
-	int new_heartbeat;
-	void __user *argp = (void __user *)arg;
-	int __user *p = argp;
-	static const struct watchdog_info ident = {
-		.options =		WDIOF_SETTIMEOUT |
-					WDIOF_KEEPALIVEPING |
-					WDIOF_MAGICCLOSE,
-		.firmware_version =	0,
-		.identity =		ESB_MODULE_NAME,
-	};
-
-	switch (cmd) {
-	case WDIOC_GETSUPPORT:
-		return copy_to_user(argp, &ident,
-					sizeof(ident)) ? -EFAULT : 0;
-
-	case WDIOC_GETSTATUS:
-		return put_user(0, p);
-
-	case WDIOC_GETBOOTSTATUS:
-		return put_user(triggered, p);
-
-	case WDIOC_SETOPTIONS:
-	{
-		if (get_user(new_options, p))
-			return -EFAULT;
-
-		if (new_options & WDIOS_DISABLECARD) {
-			esb_timer_stop();
-			retval = 0;
-		}
-
-		if (new_options & WDIOS_ENABLECARD) {
-			esb_timer_start();
-			retval = 0;
-		}
-		return retval;
-	}
-	case WDIOC_KEEPALIVE:
-		esb_timer_keepalive();
-		return 0;
-
-	case WDIOC_SETTIMEOUT:
-	{
-		if (get_user(new_heartbeat, p))
-			return -EFAULT;
-		if (esb_timer_set_heartbeat(new_heartbeat))
-			return -EINVAL;
-		esb_timer_keepalive();
-		/* Fall */
-	}
-	case WDIOC_GETTIMEOUT:
-		return put_user(heartbeat, p);
-	default:
-		return -ENOTTY;
-	}
-}
-
 /*
- *      Kernel Interfaces
+ * Watchdog Subsystem Interfaces
  */
 
-static const struct file_operations esb_fops = {
-	.owner = THIS_MODULE,
-	.llseek = no_llseek,
-	.write = esb_write,
-	.unlocked_ioctl = esb_ioctl,
-	.open = esb_open,
-	.release = esb_release,
+static struct watchdog_info esb_info = {
+	.identity = ESB_MODULE_NAME,
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
 };
 
-static struct miscdevice esb_miscdev = {
-	.minor = WATCHDOG_MINOR,
-	.name = "watchdog",
-	.fops = &esb_fops,
+static const struct watchdog_ops esb_ops = {
+	.owner = THIS_MODULE,
+	.start = esb_timer_start,
+	.stop = esb_timer_stop,
+	.set_timeout = esb_timer_set_heartbeat,
+	.ping = esb_timer_keepalive,
 };
 
 /*
@@ -343,38 +218,38 @@ MODULE_DEVICE_TABLE(pci, esb_pci_tbl);
  *      Init & exit routines
  */
 
-static unsigned char esb_getdevice(struct pci_dev *pdev)
+static unsigned char esb_getdevice(struct esb_dev *edev)
 {
-	if (pci_enable_device(pdev)) {
-		pr_err("failed to enable device\n");
+	if (pci_enable_device(edev->pdev)) {
+		dev_err(&edev->pdev->dev, "failed to enable device\n");
 		goto err_devput;
 	}
 
-	if (pci_request_region(pdev, 0, ESB_MODULE_NAME)) {
-		pr_err("failed to request region\n");
+	if (pci_request_region(edev->pdev, 0, ESB_MODULE_NAME)) {
+		dev_err(&edev->pdev->dev, "failed to request region\n");
 		goto err_disable;
 	}
 
-	BASEADDR = pci_ioremap_bar(pdev, 0);
-	if (BASEADDR == NULL) {
+	edev->base = pci_ioremap_bar(edev->pdev, 0);
+	if (edev->base == NULL) {
 		/* Something's wrong here, BASEADDR has to be set */
-		pr_err("failed to get BASEADDR\n");
+		dev_err(&edev->pdev->dev, "failed to get BASEADDR\n");
 		goto err_release;
 	}
 
 	/* Done */
-	esb_pci = pdev;
+	dev_set_drvdata(&edev->pdev->dev, edev);
 	return 1;
 
 err_release:
-	pci_release_region(pdev, 0);
+	pci_release_region(edev->pdev, 0);
 err_disable:
-	pci_disable_device(pdev);
+	pci_disable_device(edev->pdev);
 err_devput:
 	return 0;
 }
 
-static void esb_initdevice(void)
+static void esb_initdevice(struct esb_dev *edev)
 {
 	u8 val1;
 	u16 val2;
@@ -391,96 +266,87 @@ static void esb_initdevice(void)
 	 * any interrupts as there is not much we can do with it
 	 * right now.
 	 */
-	pci_write_config_word(esb_pci, ESB_CONFIG_REG, 0x0003);
+	pci_write_config_word(edev->pdev, ESB_CONFIG_REG, 0x0003);
 
 	/* Check that the WDT isn't already locked */
-	pci_read_config_byte(esb_pci, ESB_LOCK_REG, &val1);
+	pci_read_config_byte(edev->pdev, ESB_LOCK_REG, &val1);
 	if (val1 & ESB_WDT_LOCK)
-		pr_warn("nowayout already set\n");
+		dev_warn(&edev->pdev->dev, "nowayout already set\n");
 
 	/* Set the timer to watchdog mode and disable it for now */
-	pci_write_config_byte(esb_pci, ESB_LOCK_REG, 0x00);
+	pci_write_config_byte(edev->pdev, ESB_LOCK_REG, 0x00);
 
 	/* Check if the watchdog was previously triggered */
-	esb_unlock_registers();
-	val2 = readw(ESB_RELOAD_REG);
+	esb_unlock_registers(edev);
+	val2 = readw(ESB_RELOAD_REG(edev));
 	if (val2 & ESB_WDT_TIMEOUT)
-		triggered = WDIOF_CARDRESET;
+		edev->wdd.bootstatus = WDIOF_CARDRESET;
 
 	/* Reset WDT_TIMEOUT flag and timers */
-	esb_unlock_registers();
-	writew((ESB_WDT_TIMEOUT | ESB_WDT_RELOAD), ESB_RELOAD_REG);
+	esb_unlock_registers(edev);
+	writew((ESB_WDT_TIMEOUT | ESB_WDT_RELOAD), ESB_RELOAD_REG(edev));
 
 	/* And set the correct timeout value */
-	esb_timer_set_heartbeat(heartbeat);
+	esb_timer_set_heartbeat(&edev->wdd, edev->wdd.timeout);
 }
 
 static int esb_probe(struct pci_dev *pdev,
 		const struct pci_device_id *ent)
 {
+	struct esb_dev *edev;
 	int ret;
 
-	cards_found++;
-	if (cards_found == 1)
-		pr_info("Intel 6300ESB WatchDog Timer Driver v%s\n",
-			ESB_VERSION);
-
-	if (cards_found > 1) {
-		pr_err("This driver only supports 1 device\n");
-		return -ENODEV;
-	}
+	edev = devm_kzalloc(&pdev->dev, sizeof(*edev), GFP_KERNEL);
+	if (!edev)
+		return -ENOMEM;
 
 	/* Check whether or not the hardware watchdog is there */
-	if (!esb_getdevice(pdev) || esb_pci == NULL)
+	edev->pdev = pdev;
+	if (!esb_getdevice(edev))
 		return -ENODEV;
 
-	/* Check that the heartbeat value is within it's range;
-	   if not reset to the default */
-	if (heartbeat < 0x1 || heartbeat > 2 * 0x03ff) {
-		heartbeat = WATCHDOG_HEARTBEAT;
-		pr_info("heartbeat value must be 1<heartbeat<2046, using %d\n",
-			heartbeat);
-	}
-
 	/* Initialize the watchdog and make sure it does not run */
-	esb_initdevice();
+	edev->wdd.info = &esb_info;
+	edev->wdd.ops = &esb_ops;
+	edev->wdd.min_timeout = ESB_HEARTBEAT_MIN;
+	edev->wdd.max_timeout = ESB_HEARTBEAT_MAX;
+	edev->wdd.timeout = ESB_HEARTBEAT_DEFAULT;
+	if (watchdog_init_timeout(&edev->wdd, heartbeat, NULL))
+		dev_info(&pdev->dev,
+			"heartbeat value must be " ESB_HEARTBEAT_RANGE
+			", using %u\n", edev->wdd.timeout);
+	watchdog_set_nowayout(&edev->wdd, nowayout);
+	watchdog_stop_on_reboot(&edev->wdd);
+	watchdog_stop_on_unregister(&edev->wdd);
+	esb_initdevice(edev);
 
 	/* Register the watchdog so that userspace has access to it */
-	ret = misc_register(&esb_miscdev);
+	ret = watchdog_register_device(&edev->wdd);
 	if (ret != 0) {
-		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
-		       WATCHDOG_MINOR, ret);
+		dev_err(&pdev->dev,
+			"cannot register watchdog device (err=%d)\n", ret);
 		goto err_unmap;
 	}
-	pr_info("initialized (0x%p). heartbeat=%d sec (nowayout=%d)\n",
-		BASEADDR, heartbeat, nowayout);
+	dev_info(&pdev->dev,
+		"initialized (0x%p). heartbeat=%d sec (nowayout=%d)\n",
+		edev->base, edev->wdd.timeout, nowayout);
 	return 0;
 
 err_unmap:
-	iounmap(BASEADDR);
-	pci_release_region(esb_pci, 0);
-	pci_disable_device(esb_pci);
-	esb_pci = NULL;
+	iounmap(edev->base);
+	pci_release_region(edev->pdev, 0);
+	pci_disable_device(edev->pdev);
 	return ret;
 }
 
 static void esb_remove(struct pci_dev *pdev)
 {
-	/* Stop the timer before we leave */
-	if (!nowayout)
-		esb_timer_stop();
-
-	/* Deregister */
-	misc_deregister(&esb_miscdev);
-	iounmap(BASEADDR);
-	pci_release_region(esb_pci, 0);
-	pci_disable_device(esb_pci);
-	esb_pci = NULL;
-}
+	struct esb_dev *edev = dev_get_drvdata(&pdev->dev);
 
-static void esb_shutdown(struct pci_dev *pdev)
-{
-	esb_timer_stop();
+	watchdog_unregister_device(&edev->wdd);
+	iounmap(edev->base);
+	pci_release_region(edev->pdev, 0);
+	pci_disable_device(edev->pdev);
 }
 
 static struct pci_driver esb_driver = {
@@ -488,7 +354,6 @@ static struct pci_driver esb_driver = {
 	.id_table	= esb_pci_tbl,
 	.probe          = esb_probe,
 	.remove         = esb_remove,
-	.shutdown       = esb_shutdown,
 };
 
 module_pci_driver(esb_driver);

drivers/watchdog/ib700wdt.c

@@ -218,7 +218,7 @@ static long ibwdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		if (ibwdt_set_heartbeat(new_margin))
 			return -EINVAL;
 		ibwdt_ping();
-		/* Fall */
+		/* fall through */
 
 	case WDIOC_GETTIMEOUT:
 		return put_user(timeout, p);

drivers/watchdog/imx2_wdt.c

@@ -169,15 +169,21 @@ static int imx2_wdt_ping(struct watchdog_device *wdog)
 	return 0;
 }
 
-static int imx2_wdt_set_timeout(struct watchdog_device *wdog,
-				unsigned int new_timeout)
+static void __imx2_wdt_set_timeout(struct watchdog_device *wdog,
+				   unsigned int new_timeout)
 {
 	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
 
-	wdog->timeout = new_timeout;
-
 	regmap_update_bits(wdev->regmap, IMX2_WDT_WCR, IMX2_WDT_WCR_WT,
 			   WDOG_SEC_TO_COUNT(new_timeout));
+}
+
+static int imx2_wdt_set_timeout(struct watchdog_device *wdog,
+				unsigned int new_timeout)
+{
+	__imx2_wdt_set_timeout(wdog, new_timeout);
+
+	wdog->timeout = new_timeout;
 	return 0;
 }
 
@@ -371,7 +377,11 @@ static int imx2_wdt_suspend(struct device *dev)
 
 	/* The watchdog IP block is running */
 	if (imx2_wdt_is_running(wdev)) {
-		imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME);
+		/*
+		 * Don't update wdog->timeout, we'll restore the current value
+		 * during resume.
+		 */
+		__imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME);
 		imx2_wdt_ping(wdog);
 	}
 

drivers/watchdog/jz4740_wdt.c

@@ -146,6 +146,7 @@ static const struct watchdog_ops jz4740_wdt_ops = {
 #ifdef CONFIG_OF
 static const struct of_device_id jz4740_wdt_of_matches[] = {
 	{ .compatible = "ingenic,jz4740-watchdog", },
+	{ .compatible = "ingenic,jz4780-watchdog", },
 	{ /* sentinel */ }
 };
 MODULE_DEVICE_TABLE(of, jz4740_wdt_of_matches);

drivers/watchdog/mei_wdt.c

@@ -526,12 +526,11 @@ static ssize_t mei_dbgfs_read_state(struct file *file, char __user *ubuf,
 				    size_t cnt, loff_t *ppos)
 {
 	struct mei_wdt *wdt = file->private_data;
-	const size_t bufsz = 32;
-	char buf[bufsz];
+	char buf[32];
 	ssize_t pos;
 
-	pos = scnprintf(buf, bufsz, "state: %s\n",
-			 mei_wdt_state_str(wdt->state));
+	pos = scnprintf(buf, sizeof(buf), "state: %s\n",
+			mei_wdt_state_str(wdt->state));
 
 	return simple_read_from_buffer(ubuf, cnt, ppos, buf, pos);
 }

drivers/watchdog/mpc8xxx_wdt.c

@@ -22,7 +22,6 @@
 #include <linux/fs.h>
 #include <linux/init.h>
 #include <linux/kernel.h>
-#include <linux/timer.h>
 #include <linux/of_address.h>
 #include <linux/of_platform.h>
 #include <linux/module.h>
@@ -31,10 +30,13 @@
 #include <linux/uaccess.h>
 #include <sysdev/fsl_soc.h>
 
+#define WATCHDOG_TIMEOUT 10
+
 struct mpc8xxx_wdt {
 	__be32 res0;
 	__be32 swcrr; /* System watchdog control register */
 #define SWCRR_SWTC 0xFFFF0000 /* Software Watchdog Time Count. */
+#define SWCRR_SWF  0x00000008 /* Software Watchdog Freeze (mpc8xx). */
 #define SWCRR_SWEN 0x00000004 /* Watchdog Enable bit. */
 #define SWCRR_SWRI 0x00000002 /* Software Watchdog Reset/Interrupt Select bit.*/
 #define SWCRR_SWPR 0x00000001 /* Software Watchdog Counter Prescale bit. */
@@ -52,14 +54,15 @@ struct mpc8xxx_wdt_type {
 struct mpc8xxx_wdt_ddata {
 	struct mpc8xxx_wdt __iomem *base;
 	struct watchdog_device wdd;
-	struct timer_list timer;
 	spinlock_t lock;
+	u16 swtc;
 };
 
-static u16 timeout = 0xffff;
+static u16 timeout;
 module_param(timeout, ushort, 0);
 MODULE_PARM_DESC(timeout,
-	"Watchdog timeout in ticks. (0<timeout<65536, default=65535)");
+	"Watchdog timeout in seconds. (1<timeout<65535, default="
+	__MODULE_STRING(WATCHDOG_TIMEOUT) ")");
 
 static bool reset = 1;
 module_param(reset, bool, 0);
@@ -80,31 +83,27 @@ static void mpc8xxx_wdt_keepalive(struct mpc8xxx_wdt_ddata *ddata)
 	spin_unlock(&ddata->lock);
 }
 
-static void mpc8xxx_wdt_timer_ping(struct timer_list *t)
-{
-	struct mpc8xxx_wdt_ddata *ddata = from_timer(ddata, t, timer);
-
-	mpc8xxx_wdt_keepalive(ddata);
-	/* We're pinging it twice faster than needed, just to be sure. */
-	mod_timer(&ddata->timer, jiffies + HZ * ddata->wdd.timeout / 2);
-}
-
 static int mpc8xxx_wdt_start(struct watchdog_device *w)
 {
 	struct mpc8xxx_wdt_ddata *ddata =
 		container_of(w, struct mpc8xxx_wdt_ddata, wdd);
-
-	u32 tmp = SWCRR_SWEN | SWCRR_SWPR;
+	u32 tmp = in_be32(&ddata->base->swcrr);
 
 	/* Good, fire up the show */
+	tmp &= ~(SWCRR_SWTC | SWCRR_SWF | SWCRR_SWEN | SWCRR_SWRI | SWCRR_SWPR);
+	tmp |= SWCRR_SWEN | SWCRR_SWPR | (ddata->swtc << 16);
+
 	if (reset)
 		tmp |= SWCRR_SWRI;
 
-	tmp |= timeout << 16;
-
 	out_be32(&ddata->base->swcrr, tmp);
 
-	del_timer_sync(&ddata->timer);
+	tmp = in_be32(&ddata->base->swcrr);
+	if (!(tmp & SWCRR_SWEN))
+		return -EOPNOTSUPP;
+
+	ddata->swtc = tmp >> 16;
+	set_bit(WDOG_HW_RUNNING, &ddata->wdd.status);
 
 	return 0;
 }
@@ -118,17 +117,8 @@ static int mpc8xxx_wdt_ping(struct watchdog_device *w)
 	return 0;
 }
 
-static int mpc8xxx_wdt_stop(struct watchdog_device *w)
-{
-	struct mpc8xxx_wdt_ddata *ddata =
-		container_of(w, struct mpc8xxx_wdt_ddata, wdd);
-
-	mod_timer(&ddata->timer, jiffies);
-	return 0;
-}
-
 static struct watchdog_info mpc8xxx_wdt_info = {
-	.options = WDIOF_KEEPALIVEPING,
+	.options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT,
 	.firmware_version = 1,
 	.identity = "MPC8xxx",
 };
@@ -137,7 +127,6 @@ static struct watchdog_ops mpc8xxx_wdt_ops = {
 	.owner = THIS_MODULE,
 	.start = mpc8xxx_wdt_start,
 	.ping = mpc8xxx_wdt_ping,
-	.stop = mpc8xxx_wdt_stop,
 };
 
 static int mpc8xxx_wdt_probe(struct platform_device *ofdev)
@@ -148,7 +137,6 @@ static int mpc8xxx_wdt_probe(struct platform_device *ofdev)
 	struct mpc8xxx_wdt_ddata *ddata;
 	u32 freq = fsl_get_sys_freq();
 	bool enabled;
-	unsigned int timeout_sec;
 
 	wdt_type = of_device_get_match_data(&ofdev->dev);
 	if (!wdt_type)
@@ -173,26 +161,17 @@ static int mpc8xxx_wdt_probe(struct platform_device *ofdev)
 	}
 
 	spin_lock_init(&ddata->lock);
-	timer_setup(&ddata->timer, mpc8xxx_wdt_timer_ping, 0);
 
 	ddata->wdd.info = &mpc8xxx_wdt_info,
 	ddata->wdd.ops = &mpc8xxx_wdt_ops,
 
-	/* Calculate the timeout in seconds */
-	timeout_sec = (timeout * wdt_type->prescaler) / freq;
-
-	ddata->wdd.timeout = timeout_sec;
+	ddata->wdd.timeout = WATCHDOG_TIMEOUT;
+	watchdog_init_timeout(&ddata->wdd, timeout, &ofdev->dev);
 
 	watchdog_set_nowayout(&ddata->wdd, nowayout);
 
-	ret = watchdog_register_device(&ddata->wdd);
-	if (ret) {
-		pr_err("cannot register watchdog device (err=%d)\n", ret);
-		return ret;
-	}
-
-	pr_info("WDT driver for MPC8xxx initialized. mode:%s timeout=%d (%d seconds)\n",
-		reset ? "reset" : "interrupt", timeout, timeout_sec);
+	ddata->swtc = min(ddata->wdd.timeout * freq / wdt_type->prescaler,
+			  0xffffU);
 
 	/*
 	 * If the watchdog was previously enabled or we're running on
@@ -200,7 +179,22 @@ static int mpc8xxx_wdt_probe(struct platform_device *ofdev)
 	 * userspace handles it.
 	 */
 	if (enabled)
-		mod_timer(&ddata->timer, jiffies);
+		mpc8xxx_wdt_start(&ddata->wdd);
+
+	ddata->wdd.max_hw_heartbeat_ms = (ddata->swtc * wdt_type->prescaler) /
+					 (freq / 1000);
+	ddata->wdd.min_timeout = ddata->wdd.max_hw_heartbeat_ms / 1000;
+	if (ddata->wdd.timeout < ddata->wdd.min_timeout)
+		ddata->wdd.timeout = ddata->wdd.min_timeout;
+
+	ret = watchdog_register_device(&ddata->wdd);
+	if (ret) {
+		pr_err("cannot register watchdog device (err=%d)\n", ret);
+		return ret;
+	}
+
+	pr_info("WDT driver for MPC8xxx initialized. mode:%s timeout=%d sec\n",
+		reset ? "reset" : "interrupt", ddata->wdd.timeout);
 
 	platform_set_drvdata(ofdev, ddata);
 	return 0;
@@ -212,7 +206,6 @@ static int mpc8xxx_wdt_remove(struct platform_device *ofdev)
 
 	pr_crit("Watchdog removed, expect the %s soon!\n",
 		reset ? "reset" : "machine check exception");
-	del_timer_sync(&ddata->timer);
 	watchdog_unregister_device(&ddata->wdd);
 
 	return 0;

drivers/watchdog/mt7621_wdt.c

@@ -105,6 +105,11 @@ static int mt7621_wdt_bootcause(void)
 	return 0;
 }
 
+static int mt7621_wdt_is_running(struct watchdog_device *w)
+{
+	return !!(rt_wdt_r32(TIMER_REG_TMR1CTL) & TMR1CTL_ENABLE);
+}
+
 static const struct watchdog_info mt7621_wdt_info = {
 	.identity = "Mediatek Watchdog",
 	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
@@ -128,7 +133,6 @@ static struct watchdog_device mt7621_wdt_dev = {
 static int mt7621_wdt_probe(struct platform_device *pdev)
 {
 	struct resource *res;
-	int ret;
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	mt7621_wdt_base = devm_ioremap_resource(&pdev->dev, res);
@@ -144,17 +148,22 @@ static int mt7621_wdt_probe(struct platform_device *pdev)
 	watchdog_init_timeout(&mt7621_wdt_dev, mt7621_wdt_dev.max_timeout,
 			      &pdev->dev);
 	watchdog_set_nowayout(&mt7621_wdt_dev, nowayout);
-
-	ret = watchdog_register_device(&mt7621_wdt_dev);
-
-	return 0;
-}
-
-static int mt7621_wdt_remove(struct platform_device *pdev)
-{
-	watchdog_unregister_device(&mt7621_wdt_dev);
-
-	return 0;
+	if (mt7621_wdt_is_running(&mt7621_wdt_dev)) {
+		/*
+		 * Make sure to apply timeout from watchdog core, taking
+		 * the prescaler of this driver here into account (the
+		 * boot loader might be using a different prescaler).
+		 *
+		 * To avoid spurious resets because of different scaling,
+		 * we first disable the watchdog, set the new prescaler
+		 * and timeout, and then re-enable the watchdog.
+		 */
+		mt7621_wdt_stop(&mt7621_wdt_dev);
+		mt7621_wdt_start(&mt7621_wdt_dev);
+		set_bit(WDOG_HW_RUNNING, &mt7621_wdt_dev.status);
+	}
+
+	return devm_watchdog_register_device(&pdev->dev, &mt7621_wdt_dev);
 }
 
 static void mt7621_wdt_shutdown(struct platform_device *pdev)
@@ -170,7 +179,6 @@ MODULE_DEVICE_TABLE(of, mt7621_wdt_match);
 
 static struct platform_driver mt7621_wdt_driver = {
 	.probe		= mt7621_wdt_probe,
-	.remove		= mt7621_wdt_remove,
 	.shutdown	= mt7621_wdt_shutdown,
 	.driver		= {
 		.name		= KBUILD_MODNAME,

drivers/watchdog/orion_wdt.c

@@ -576,7 +576,7 @@ static int orion_wdt_probe(struct platform_device *pdev)
 	/*
 	 * Let's make sure the watchdog is fully stopped, unless it's
 	 * explicitly enabled. This may be the case if the module was
-	 * removed and re-insterted, or if the bootloader explicitly
+	 * removed and re-inserted, or if the bootloader explicitly
 	 * set a running watchdog before booting the kernel.
 	 */
 	if (!orion_wdt_enabled(&dev->wdt))

drivers/watchdog/pcwd_pci.c

@@ -545,8 +545,8 @@ static long pcipcwd_ioctl(struct file *file, unsigned int cmd,
 			return -EINVAL;
 
 		pcipcwd_keepalive();
-		/* Fall */
 	}
+		/* fall through */
 
 	case WDIOC_GETTIMEOUT:
 		return put_user(heartbeat, p);

drivers/watchdog/pcwd_usb.c

@@ -49,12 +49,11 @@
 #define DRIVER_VERSION "1.02"
 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
-#define DRIVER_LICENSE "GPL"
 #define DRIVER_NAME "pcwd_usb"
 
 MODULE_AUTHOR(DRIVER_AUTHOR);
 MODULE_DESCRIPTION(DRIVER_DESC);
-MODULE_LICENSE(DRIVER_LICENSE);
+MODULE_LICENSE("GPL");
 
 #define WATCHDOG_HEARTBEAT 0	/* default heartbeat =
 						delay-time from dip-switches */
@@ -456,8 +455,8 @@ static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
 			return -EINVAL;
 
 		usb_pcwd_keepalive(usb_pcwd_device);
-		/* Fall */
 	}
+		/* fall through */
 
 	case WDIOC_GETTIMEOUT:
 		return put_user(heartbeat, p);

drivers/watchdog/rtd119x_wdt.c

+/*
+ * Realtek RTD129x watchdog
+ *
+ * Copyright (c) 2017 Andreas Färber
+ *
+ * SPDX-License-Identifier: GPL-2.0+
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+#define RTD119X_TCWCR		0x0
+#define RTD119X_TCWTR		0x4
+#define RTD119X_TCWOV		0xc
+
+#define RTD119X_TCWCR_WDEN_DISABLED		0xa5
+#define RTD119X_TCWCR_WDEN_ENABLED		0xff
+#define RTD119X_TCWCR_WDEN_MASK			0xff
+
+#define RTD119X_TCWTR_WDCLR			BIT(0)
+
+struct rtd119x_watchdog_device {
+	struct watchdog_device wdt_dev;
+	void __iomem *base;
+	struct clk *clk;
+};
+
+static int rtd119x_wdt_start(struct watchdog_device *wdev)
+{
+	struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
+	u32 val;
+
+	val = readl_relaxed(data->base + RTD119X_TCWCR);
+	val &= ~RTD119X_TCWCR_WDEN_MASK;
+	val |= RTD119X_TCWCR_WDEN_ENABLED;
+	writel(val, data->base + RTD119X_TCWCR);
+
+	return 0;
+}
+
+static int rtd119x_wdt_stop(struct watchdog_device *wdev)
+{
+	struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
+	u32 val;
+
+	val = readl_relaxed(data->base + RTD119X_TCWCR);
+	val &= ~RTD119X_TCWCR_WDEN_MASK;
+	val |= RTD119X_TCWCR_WDEN_DISABLED;
+	writel(val, data->base + RTD119X_TCWCR);
+
+	return 0;
+}
+
+static int rtd119x_wdt_ping(struct watchdog_device *wdev)
+{
+	struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
+
+	writel_relaxed(RTD119X_TCWTR_WDCLR, data->base + RTD119X_TCWTR);
+
+	return rtd119x_wdt_start(wdev);
+}
+
+static int rtd119x_wdt_set_timeout(struct watchdog_device *wdev, unsigned int val)
+{
+	struct rtd119x_watchdog_device *data = watchdog_get_drvdata(wdev);
+
+	writel(val * clk_get_rate(data->clk), data->base + RTD119X_TCWOV);
+
+	data->wdt_dev.timeout = val;
+
+	return 0;
+}
+
+static const struct watchdog_ops rtd119x_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start		= rtd119x_wdt_start,
+	.stop		= rtd119x_wdt_stop,
+	.ping		= rtd119x_wdt_ping,
+	.set_timeout	= rtd119x_wdt_set_timeout,
+};
+
+static const struct watchdog_info rtd119x_wdt_info = {
+	.identity = "rtd119x-wdt",
+	.options = 0,
+};
+
+static const struct of_device_id rtd119x_wdt_dt_ids[] = {
+	 { .compatible = "realtek,rtd1295-watchdog" },
+	 { }
+};
+
+static int rtd119x_wdt_probe(struct platform_device *pdev)
+{
+	struct rtd119x_watchdog_device *data;
+	struct resource *res;
+	int ret;
+
+	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	data->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(data->base))
+		return PTR_ERR(data->base);
+
+	data->clk = of_clk_get(pdev->dev.of_node, 0);
+	if (IS_ERR(data->clk))
+		return PTR_ERR(data->clk);
+
+	ret = clk_prepare_enable(data->clk);
+	if (ret) {
+		clk_put(data->clk);
+		return ret;
+	}
+
+	data->wdt_dev.info = &rtd119x_wdt_info;
+	data->wdt_dev.ops = &rtd119x_wdt_ops;
+	data->wdt_dev.timeout = 120;
+	data->wdt_dev.max_timeout = 0xffffffff / clk_get_rate(data->clk);
+	data->wdt_dev.min_timeout = 1;
+	data->wdt_dev.parent = &pdev->dev;
+
+	watchdog_stop_on_reboot(&data->wdt_dev);
+	watchdog_set_drvdata(&data->wdt_dev, data);
+	platform_set_drvdata(pdev, data);
+
+	writel_relaxed(RTD119X_TCWTR_WDCLR, data->base + RTD119X_TCWTR);
+	rtd119x_wdt_set_timeout(&data->wdt_dev, data->wdt_dev.timeout);
+	rtd119x_wdt_stop(&data->wdt_dev);
+
+	ret = devm_watchdog_register_device(&pdev->dev, &data->wdt_dev);
+	if (ret) {
+		clk_disable_unprepare(data->clk);
+		clk_put(data->clk);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rtd119x_wdt_remove(struct platform_device *pdev)
+{
+	struct rtd119x_watchdog_device *data = platform_get_drvdata(pdev);
+
+	watchdog_unregister_device(&data->wdt_dev);
+
+	clk_disable_unprepare(data->clk);
+	clk_put(data->clk);
+
+	return 0;
+}
+
+static struct platform_driver rtd119x_wdt_driver = {
+	.probe = rtd119x_wdt_probe,
+	.remove = rtd119x_wdt_remove,
+	.driver = {
+		.name = "rtd1295-watchdog",
+		.of_match_table	= rtd119x_wdt_dt_ids,
+	},
+};
+builtin_platform_driver(rtd119x_wdt_driver);

drivers/watchdog/sp5100_tco.c

@@ -16,6 +16,11 @@
  *	See AMD Publication 43009 "AMD SB700/710/750 Register Reference Guide",
  *	    AMD Publication 45482 "AMD SB800-Series Southbridges Register
  *	                                                      Reference Guide"
+ *	    AMD Publication 48751 "BIOS and Kernel Developer’s Guide (BKDG)
+ *				for AMD Family 16h Models 00h-0Fh Processors"
+ *	    AMD Publication 51192 "AMD Bolton FCH Register Reference Guide"
+ *	    AMD Publication 52740 "BIOS and Kernel Developer’s Guide (BKDG)
+ *				for AMD Family 16h Models 30h-3Fh Processors"
  */
 
 /*
@@ -24,38 +29,36 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
-#include <linux/types.h>
-#include <linux/miscdevice.h>
-#include <linux/watchdog.h>
-#include <linux/init.h>
-#include <linux/fs.h>
 #include <linux/pci.h>
-#include <linux/ioport.h>
 #include <linux/platform_device.h>
-#include <linux/uaccess.h>
-#include <linux/io.h>
+#include <linux/types.h>
+#include <linux/watchdog.h>
 
 #include "sp5100_tco.h"
 
-/* Module and version information */
-#define TCO_VERSION "0.05"
-#define TCO_MODULE_NAME "SP5100 TCO timer"
-#define TCO_DRIVER_NAME   TCO_MODULE_NAME ", v" TCO_VERSION
+#define TCO_DRIVER_NAME	"sp5100-tco"
 
 /* internal variables */
-static u32 tcobase_phys;
-static u32 tco_wdt_fired;
-static void __iomem *tcobase;
-static unsigned int pm_iobase;
-static DEFINE_SPINLOCK(tco_lock);	/* Guards the hardware */
-static unsigned long timer_alive;
-static char tco_expect_close;
-static struct pci_dev *sp5100_tco_pci;
+
+enum tco_reg_layout {
+	sp5100, sb800, efch
+};
+
+struct sp5100_tco {
+	struct watchdog_device wdd;
+	void __iomem *tcobase;
+	enum tco_reg_layout tco_reg_layout;
+};
 
 /* the watchdog platform device */
 static struct platform_device *sp5100_tco_platform_device;
+/* the associated PCI device */
+static struct pci_dev *sp5100_tco_pci;
 
 /* module parameters */
 
@@ -74,83 +77,105 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started."
  * Some TCO specific functions
  */
 
-static bool tco_has_sp5100_reg_layout(struct pci_dev *dev)
+static enum tco_reg_layout tco_reg_layout(struct pci_dev *dev)
 {
-	return dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS &&
-	       dev->revision < 0x40;
+	if (dev->vendor == PCI_VENDOR_ID_ATI &&
+	    dev->device == PCI_DEVICE_ID_ATI_SBX00_SMBUS &&
+	    dev->revision < 0x40) {
+		return sp5100;
+	} else if (dev->vendor == PCI_VENDOR_ID_AMD &&
+	    ((dev->device == PCI_DEVICE_ID_AMD_HUDSON2_SMBUS &&
+	     dev->revision >= 0x41) ||
+	    (dev->device == PCI_DEVICE_ID_AMD_KERNCZ_SMBUS &&
+	     dev->revision >= 0x49))) {
+		return efch;
+	}
+	return sb800;
 }
 
-static void tco_timer_start(void)
+static int tco_timer_start(struct watchdog_device *wdd)
 {
+	struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
 	u32 val;
-	unsigned long flags;
 
-	spin_lock_irqsave(&tco_lock, flags);
-	val = readl(SP5100_WDT_CONTROL(tcobase));
+	val = readl(SP5100_WDT_CONTROL(tco->tcobase));
 	val |= SP5100_WDT_START_STOP_BIT;
-	writel(val, SP5100_WDT_CONTROL(tcobase));
-	spin_unlock_irqrestore(&tco_lock, flags);
+	writel(val, SP5100_WDT_CONTROL(tco->tcobase));
+
+	return 0;
 }
 
-static void tco_timer_stop(void)
+static int tco_timer_stop(struct watchdog_device *wdd)
 {
+	struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
 	u32 val;
-	unsigned long flags;
 
-	spin_lock_irqsave(&tco_lock, flags);
-	val = readl(SP5100_WDT_CONTROL(tcobase));
+	val = readl(SP5100_WDT_CONTROL(tco->tcobase));
 	val &= ~SP5100_WDT_START_STOP_BIT;
-	writel(val, SP5100_WDT_CONTROL(tcobase));
-	spin_unlock_irqrestore(&tco_lock, flags);
+	writel(val, SP5100_WDT_CONTROL(tco->tcobase));
+
+	return 0;
 }
 
-static void tco_timer_keepalive(void)
+static int tco_timer_ping(struct watchdog_device *wdd)
 {
+	struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
 	u32 val;
-	unsigned long flags;
 
-	spin_lock_irqsave(&tco_lock, flags);
-	val = readl(SP5100_WDT_CONTROL(tcobase));
+	val = readl(SP5100_WDT_CONTROL(tco->tcobase));
 	val |= SP5100_WDT_TRIGGER_BIT;
-	writel(val, SP5100_WDT_CONTROL(tcobase));
-	spin_unlock_irqrestore(&tco_lock, flags);
+	writel(val, SP5100_WDT_CONTROL(tco->tcobase));
+
+	return 0;
 }
 
-static int tco_timer_set_heartbeat(int t)
+static int tco_timer_set_timeout(struct watchdog_device *wdd,
+				 unsigned int t)
 {
-	unsigned long flags;
-
-	if (t < 0 || t > 0xffff)
-		return -EINVAL;
+	struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
 
 	/* Write new heartbeat to watchdog */
-	spin_lock_irqsave(&tco_lock, flags);
-	writel(t, SP5100_WDT_COUNT(tcobase));
-	spin_unlock_irqrestore(&tco_lock, flags);
+	writel(t, SP5100_WDT_COUNT(tco->tcobase));
+
+	wdd->timeout = t;
 
-	heartbeat = t;
 	return 0;
 }
 
-static void tco_timer_enable(void)
+static u8 sp5100_tco_read_pm_reg8(u8 index)
+{
+	outb(index, SP5100_IO_PM_INDEX_REG);
+	return inb(SP5100_IO_PM_DATA_REG);
+}
+
+static void sp5100_tco_update_pm_reg8(u8 index, u8 reset, u8 set)
+{
+	u8 val;
+
+	outb(index, SP5100_IO_PM_INDEX_REG);
+	val = inb(SP5100_IO_PM_DATA_REG);
+	val &= reset;
+	val |= set;
+	outb(val, SP5100_IO_PM_DATA_REG);
+}
+
+static void tco_timer_enable(struct sp5100_tco *tco)
 {
-	int val;
+	u32 val;
 
-	if (!tco_has_sp5100_reg_layout(sp5100_tco_pci)) {
+	switch (tco->tco_reg_layout) {
+	case sb800:
 		/* For SB800 or later */
 		/* Set the Watchdog timer resolution to 1 sec */
-		outb(SB800_PM_WATCHDOG_CONFIG, SB800_IO_PM_INDEX_REG);
-		val = inb(SB800_IO_PM_DATA_REG);
-		val |= SB800_PM_WATCHDOG_SECOND_RES;
-		outb(val, SB800_IO_PM_DATA_REG);
+		sp5100_tco_update_pm_reg8(SB800_PM_WATCHDOG_CONFIG,
+					  0xff, SB800_PM_WATCHDOG_SECOND_RES);
 
 		/* Enable watchdog decode bit and watchdog timer */
-		outb(SB800_PM_WATCHDOG_CONTROL, SB800_IO_PM_INDEX_REG);
-		val = inb(SB800_IO_PM_DATA_REG);
-		val |= SB800_PCI_WATCHDOG_DECODE_EN;
-		val &= ~SB800_PM_WATCHDOG_DISABLE;
-		outb(val, SB800_IO_PM_DATA_REG);
-	} else {
+		sp5100_tco_update_pm_reg8(SB800_PM_WATCHDOG_CONTROL,
+					  ~SB800_PM_WATCHDOG_DISABLE,
+					  SB800_PCI_WATCHDOG_DECODE_EN);
+		break;
+	case sp5100:
 		/* For SP5100 or SB7x0 */
 		/* Enable watchdog decode bit */
 		pci_read_config_dword(sp5100_tco_pci,
@@ -164,409 +189,287 @@ static void tco_timer_enable(void)
 				       val);
 
 		/* Enable Watchdog timer and set the resolution to 1 sec */
-		outb(SP5100_PM_WATCHDOG_CONTROL, SP5100_IO_PM_INDEX_REG);
-		val = inb(SP5100_IO_PM_DATA_REG);
-		val |= SP5100_PM_WATCHDOG_SECOND_RES;
-		val &= ~SP5100_PM_WATCHDOG_DISABLE;
-		outb(val, SP5100_IO_PM_DATA_REG);
+		sp5100_tco_update_pm_reg8(SP5100_PM_WATCHDOG_CONTROL,
+					  ~SP5100_PM_WATCHDOG_DISABLE,
+					  SP5100_PM_WATCHDOG_SECOND_RES);
+		break;
+	case efch:
+		/* Set the Watchdog timer resolution to 1 sec and enable */
+		sp5100_tco_update_pm_reg8(EFCH_PM_DECODEEN3,
+					  ~EFCH_PM_WATCHDOG_DISABLE,
+					  EFCH_PM_DECODEEN_SECOND_RES);
+		break;
 	}
 }
 
-/*
- *	/dev/watchdog handling
- */
-
-static int sp5100_tco_open(struct inode *inode, struct file *file)
+static u32 sp5100_tco_read_pm_reg32(u8 index)
 {
-	/* /dev/watchdog can only be opened once */
-	if (test_and_set_bit(0, &timer_alive))
-		return -EBUSY;
-
-	/* Reload and activate timer */
-	tco_timer_start();
-	tco_timer_keepalive();
-	return nonseekable_open(inode, file);
-}
-
-static int sp5100_tco_release(struct inode *inode, struct file *file)
-{
-	/* Shut off the timer. */
-	if (tco_expect_close == 42) {
-		tco_timer_stop();
-	} else {
-		pr_crit("Unexpected close, not stopping watchdog!\n");
-		tco_timer_keepalive();
-	}
-	clear_bit(0, &timer_alive);
-	tco_expect_close = 0;
-	return 0;
-}
-
-static ssize_t sp5100_tco_write(struct file *file, const char __user *data,
-				size_t len, loff_t *ppos)
-{
-	/* See if we got the magic character 'V' and reload the timer */
-	if (len) {
-		if (!nowayout) {
-			size_t i;
-
-			/* note: just in case someone wrote the magic character
-			 * five months ago... */
-			tco_expect_close = 0;
+	u32 val = 0;
+	int i;
 
-			/* scan to see whether or not we got the magic character
-			 */
-			for (i = 0; i != len; i++) {
-				char c;
-				if (get_user(c, data + i))
-					return -EFAULT;
-				if (c == 'V')
-					tco_expect_close = 42;
-			}
-		}
+	for (i = 3; i >= 0; i--)
+		val = (val << 8) + sp5100_tco_read_pm_reg8(index + i);
 
-		/* someone wrote to us, we should reload the timer */
-		tco_timer_keepalive();
-	}
-	return len;
+	return val;
 }
 
-static long sp5100_tco_ioctl(struct file *file, unsigned int cmd,
-			     unsigned long arg)
+static int sp5100_tco_setupdevice(struct device *dev,
+				  struct watchdog_device *wdd)
 {
-	int new_options, retval = -EINVAL;
-	int new_heartbeat;
-	void __user *argp = (void __user *)arg;
-	int __user *p = argp;
-	static const struct watchdog_info ident = {
-		.options =		WDIOF_SETTIMEOUT |
-					WDIOF_KEEPALIVEPING |
-					WDIOF_MAGICCLOSE,
-		.firmware_version =	0,
-		.identity =		TCO_MODULE_NAME,
-	};
-
-	switch (cmd) {
-	case WDIOC_GETSUPPORT:
-		return copy_to_user(argp, &ident,
-			sizeof(ident)) ? -EFAULT : 0;
-	case WDIOC_GETSTATUS:
-	case WDIOC_GETBOOTSTATUS:
-		return put_user(0, p);
-	case WDIOC_SETOPTIONS:
-		if (get_user(new_options, p))
-			return -EFAULT;
-		if (new_options & WDIOS_DISABLECARD) {
-			tco_timer_stop();
-			retval = 0;
-		}
-		if (new_options & WDIOS_ENABLECARD) {
-			tco_timer_start();
-			tco_timer_keepalive();
-			retval = 0;
-		}
-		return retval;
-	case WDIOC_KEEPALIVE:
-		tco_timer_keepalive();
-		return 0;
-	case WDIOC_SETTIMEOUT:
-		if (get_user(new_heartbeat, p))
-			return -EFAULT;
-		if (tco_timer_set_heartbeat(new_heartbeat))
-			return -EINVAL;
-		tco_timer_keepalive();
-		/* Fall through */
-	case WDIOC_GETTIMEOUT:
-		return put_user(heartbeat, p);
-	default:
-		return -ENOTTY;
-	}
-}
-
-/*
- * Kernel Interfaces
- */
-
-static const struct file_operations sp5100_tco_fops = {
-	.owner =		THIS_MODULE,
-	.llseek =		no_llseek,
-	.write =		sp5100_tco_write,
-	.unlocked_ioctl =	sp5100_tco_ioctl,
-	.open =			sp5100_tco_open,
-	.release =		sp5100_tco_release,
-};
-
-static struct miscdevice sp5100_tco_miscdev = {
-	.minor =	WATCHDOG_MINOR,
-	.name =		"watchdog",
-	.fops =		&sp5100_tco_fops,
-};
-
-/*
- * Data for PCI driver interface
- *
- * This data only exists for exporting the supported
- * PCI ids via MODULE_DEVICE_TABLE.  We do not actually
- * register a pci_driver, because someone else might
- * want to register another driver on the same PCI id.
- */
-static const struct pci_device_id sp5100_tco_pci_tbl[] = {
-	{ PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS, PCI_ANY_ID,
-	  PCI_ANY_ID, },
-	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_HUDSON2_SMBUS, PCI_ANY_ID,
-	  PCI_ANY_ID, },
-	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS, PCI_ANY_ID,
-	  PCI_ANY_ID, },
-	{ 0, },			/* End of list */
-};
-MODULE_DEVICE_TABLE(pci, sp5100_tco_pci_tbl);
-
-/*
- * Init & exit routines
- */
-static unsigned char sp5100_tco_setupdevice(void)
-{
-	struct pci_dev *dev = NULL;
-	const char *dev_name = NULL;
-	u32 val;
-	u32 index_reg, data_reg, base_addr;
+	struct sp5100_tco *tco = watchdog_get_drvdata(wdd);
+	const char *dev_name;
+	u32 mmio_addr = 0, val;
+	int ret;
 
-	/* Match the PCI device */
-	for_each_pci_dev(dev) {
-		if (pci_match_id(sp5100_tco_pci_tbl, dev) != NULL) {
-			sp5100_tco_pci = dev;
-			break;
-		}
+	/* Request the IO ports used by this driver */
+	if (!request_muxed_region(SP5100_IO_PM_INDEX_REG,
+				  SP5100_PM_IOPORTS_SIZE, "sp5100_tco")) {
+		dev_err(dev, "I/O address 0x%04x already in use\n",
+			SP5100_IO_PM_INDEX_REG);
+		return -EBUSY;
 	}
 
-	if (!sp5100_tco_pci)
-		return 0;
-
-	pr_info("PCI Vendor ID: 0x%x, Device ID: 0x%x, Revision ID: 0x%x\n",
-		sp5100_tco_pci->vendor, sp5100_tco_pci->device,
-		sp5100_tco_pci->revision);
-
 	/*
 	 * Determine type of southbridge chipset.
 	 */
-	if (tco_has_sp5100_reg_layout(sp5100_tco_pci)) {
+	switch (tco->tco_reg_layout) {
+	case sp5100:
 		dev_name = SP5100_DEVNAME;
-		index_reg = SP5100_IO_PM_INDEX_REG;
-		data_reg = SP5100_IO_PM_DATA_REG;
-		base_addr = SP5100_PM_WATCHDOG_BASE;
-	} else {
+		mmio_addr = sp5100_tco_read_pm_reg32(SP5100_PM_WATCHDOG_BASE) &
+								0xfffffff8;
+		break;
+	case sb800:
 		dev_name = SB800_DEVNAME;
-		index_reg = SB800_IO_PM_INDEX_REG;
-		data_reg = SB800_IO_PM_DATA_REG;
-		base_addr = SB800_PM_WATCHDOG_BASE;
-	}
-
-	/* Request the IO ports used by this driver */
-	pm_iobase = SP5100_IO_PM_INDEX_REG;
-	if (!request_region(pm_iobase, SP5100_PM_IOPORTS_SIZE, dev_name)) {
-		pr_err("I/O address 0x%04x already in use\n", pm_iobase);
-		goto exit;
+		mmio_addr = sp5100_tco_read_pm_reg32(SB800_PM_WATCHDOG_BASE) &
+								0xfffffff8;
+		break;
+	case efch:
+		dev_name = SB800_DEVNAME;
+		val = sp5100_tco_read_pm_reg8(EFCH_PM_DECODEEN);
+		if (val & EFCH_PM_DECODEEN_WDT_TMREN)
+			mmio_addr = EFCH_PM_WDT_ADDR;
+		break;
+	default:
+		return -ENODEV;
 	}
 
-	/*
-	 * First, Find the watchdog timer MMIO address from indirect I/O.
-	 */
-	outb(base_addr+3, index_reg);
-	val = inb(data_reg);
-	outb(base_addr+2, index_reg);
-	val = val << 8 | inb(data_reg);
-	outb(base_addr+1, index_reg);
-	val = val << 8 | inb(data_reg);
-	outb(base_addr+0, index_reg);
-	/* Low three bits of BASE are reserved */
-	val = val << 8 | (inb(data_reg) & 0xf8);
-
-	pr_debug("Got 0x%04x from indirect I/O\n", val);
-
 	/* Check MMIO address conflict */
-	if (request_mem_region_exclusive(val, SP5100_WDT_MEM_MAP_SIZE,
-								dev_name))
-		goto setup_wdt;
-	else
-		pr_debug("MMIO address 0x%04x already in use\n", val);
-
-	/*
-	 * Secondly, Find the watchdog timer MMIO address
-	 * from SBResource_MMIO register.
-	 */
-	if (tco_has_sp5100_reg_layout(sp5100_tco_pci)) {
-		/* Read SBResource_MMIO from PCI config(PCI_Reg: 9Ch) */
-		pci_read_config_dword(sp5100_tco_pci,
-				      SP5100_SB_RESOURCE_MMIO_BASE, &val);
-	} else {
-		/* Read SBResource_MMIO from AcpiMmioEn(PM_Reg: 24h) */
-		outb(SB800_PM_ACPI_MMIO_EN+3, SB800_IO_PM_INDEX_REG);
-		val = inb(SB800_IO_PM_DATA_REG);
-		outb(SB800_PM_ACPI_MMIO_EN+2, SB800_IO_PM_INDEX_REG);
-		val = val << 8 | inb(SB800_IO_PM_DATA_REG);
-		outb(SB800_PM_ACPI_MMIO_EN+1, SB800_IO_PM_INDEX_REG);
-		val = val << 8 | inb(SB800_IO_PM_DATA_REG);
-		outb(SB800_PM_ACPI_MMIO_EN+0, SB800_IO_PM_INDEX_REG);
-		val = val << 8 | inb(SB800_IO_PM_DATA_REG);
+	if (!mmio_addr ||
+	    !devm_request_mem_region(dev, mmio_addr, SP5100_WDT_MEM_MAP_SIZE,
+				     dev_name)) {
+		if (mmio_addr)
+			dev_dbg(dev, "MMIO address 0x%08x already in use\n",
+				mmio_addr);
+		switch (tco->tco_reg_layout) {
+		case sp5100:
+			/*
+			 * Secondly, Find the watchdog timer MMIO address
+			 * from SBResource_MMIO register.
+			 */
+			/* Read SBResource_MMIO from PCI config(PCI_Reg: 9Ch) */
+			pci_read_config_dword(sp5100_tco_pci,
+					      SP5100_SB_RESOURCE_MMIO_BASE,
+					      &mmio_addr);
+			if ((mmio_addr & (SB800_ACPI_MMIO_DECODE_EN |
+					  SB800_ACPI_MMIO_SEL)) !=
+						  SB800_ACPI_MMIO_DECODE_EN) {
+				ret = -ENODEV;
+				goto unreg_region;
+			}
+			mmio_addr &= ~0xFFF;
+			mmio_addr += SB800_PM_WDT_MMIO_OFFSET;
+			break;
+		case sb800:
+			/* Read SBResource_MMIO from AcpiMmioEn(PM_Reg: 24h) */
+			mmio_addr =
+				sp5100_tco_read_pm_reg32(SB800_PM_ACPI_MMIO_EN);
+			if ((mmio_addr & (SB800_ACPI_MMIO_DECODE_EN |
+					  SB800_ACPI_MMIO_SEL)) !=
+						  SB800_ACPI_MMIO_DECODE_EN) {
+				ret = -ENODEV;
+				goto unreg_region;
+			}
+			mmio_addr &= ~0xFFF;
+			mmio_addr += SB800_PM_WDT_MMIO_OFFSET;
+			break;
+		case efch:
+			val = sp5100_tco_read_pm_reg8(EFCH_PM_ISACONTROL);
+			if (!(val & EFCH_PM_ISACONTROL_MMIOEN)) {
+				ret = -ENODEV;
+				goto unreg_region;
+			}
+			mmio_addr = EFCH_PM_ACPI_MMIO_ADDR +
+				    EFCH_PM_ACPI_MMIO_WDT_OFFSET;
+			break;
+		}
+		dev_dbg(dev, "Got 0x%08x from SBResource_MMIO register\n",
+			mmio_addr);
+		if (!devm_request_mem_region(dev, mmio_addr,
+					     SP5100_WDT_MEM_MAP_SIZE,
+					     dev_name)) {
+			dev_dbg(dev, "MMIO address 0x%08x already in use\n",
+				mmio_addr);
+			ret = -EBUSY;
+			goto unreg_region;
+		}
 	}
 
-	/* The SBResource_MMIO is enabled and mapped memory space? */
-	if ((val & (SB800_ACPI_MMIO_DECODE_EN | SB800_ACPI_MMIO_SEL)) ==
-						  SB800_ACPI_MMIO_DECODE_EN) {
-		/* Clear unnecessary the low twelve bits */
-		val &= ~0xFFF;
-		/* Add the Watchdog Timer offset to base address. */
-		val += SB800_PM_WDT_MMIO_OFFSET;
-		/* Check MMIO address conflict */
-		if (request_mem_region_exclusive(val, SP5100_WDT_MEM_MAP_SIZE,
-								   dev_name)) {
-			pr_debug("Got 0x%04x from SBResource_MMIO register\n",
-				val);
-			goto setup_wdt;
-		} else
-			pr_debug("MMIO address 0x%04x already in use\n", val);
-	} else
-		pr_debug("SBResource_MMIO is disabled(0x%04x)\n", val);
-
-	pr_notice("failed to find MMIO address, giving up.\n");
-	goto  unreg_region;
-
-setup_wdt:
-	tcobase_phys = val;
-
-	tcobase = ioremap(val, SP5100_WDT_MEM_MAP_SIZE);
-	if (!tcobase) {
-		pr_err("failed to get tcobase address\n");
-		goto unreg_mem_region;
+	tco->tcobase = devm_ioremap(dev, mmio_addr, SP5100_WDT_MEM_MAP_SIZE);
+	if (!tco->tcobase) {
+		dev_err(dev, "failed to get tcobase address\n");
+		ret = -ENOMEM;
+		goto unreg_region;
 	}
 
-	pr_info("Using 0x%04x for watchdog MMIO address\n", val);
+	dev_info(dev, "Using 0x%08x for watchdog MMIO address\n", mmio_addr);
 
 	/* Setup the watchdog timer */
-	tco_timer_enable();
+	tco_timer_enable(tco);
+
+	val = readl(SP5100_WDT_CONTROL(tco->tcobase));
+	if (val & SP5100_WDT_DISABLED) {
+		dev_err(dev, "Watchdog hardware is disabled\n");
+		ret = -ENODEV;
+		goto unreg_region;
+	}
 
-	/* Check that the watchdog action is set to reset the system */
-	val = readl(SP5100_WDT_CONTROL(tcobase));
 	/*
 	 * Save WatchDogFired status, because WatchDogFired flag is
 	 * cleared here.
 	 */
-	tco_wdt_fired = val & SP5100_PM_WATCHDOG_FIRED;
-	val &= ~SP5100_PM_WATCHDOG_ACTION_RESET;
-	writel(val, SP5100_WDT_CONTROL(tcobase));
+	if (val & SP5100_WDT_FIRED)
+		wdd->bootstatus = WDIOF_CARDRESET;
+	/* Set watchdog action to reset the system */
+	val &= ~SP5100_WDT_ACTION_RESET;
+	writel(val, SP5100_WDT_CONTROL(tco->tcobase));
 
 	/* Set a reasonable heartbeat before we stop the timer */
-	tco_timer_set_heartbeat(heartbeat);
+	tco_timer_set_timeout(wdd, wdd->timeout);
 
 	/*
 	 * Stop the TCO before we change anything so we don't race with
 	 * a zeroed timer.
 	 */
-	tco_timer_stop();
+	tco_timer_stop(wdd);
 
-	/* Done */
-	return 1;
+	release_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE);
 
-unreg_mem_region:
-	release_mem_region(tcobase_phys, SP5100_WDT_MEM_MAP_SIZE);
-unreg_region:
-	release_region(pm_iobase, SP5100_PM_IOPORTS_SIZE);
-exit:
 	return 0;
-}
 
-static int sp5100_tco_init(struct platform_device *dev)
-{
-	int ret;
+unreg_region:
+	release_region(SP5100_IO_PM_INDEX_REG, SP5100_PM_IOPORTS_SIZE);
+	return ret;
+}
 
-	/*
-	 * Check whether or not the hardware watchdog is there. If found, then
-	 * set it up.
-	 */
-	if (!sp5100_tco_setupdevice())
-		return -ENODEV;
+static struct watchdog_info sp5100_tco_wdt_info = {
+	.identity = "SP5100 TCO timer",
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+};
 
-	/* Check to see if last reboot was due to watchdog timeout */
-	pr_info("Last reboot was %striggered by watchdog.\n",
-		tco_wdt_fired ? "" : "not ");
+static const struct watchdog_ops sp5100_tco_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = tco_timer_start,
+	.stop = tco_timer_stop,
+	.ping = tco_timer_ping,
+	.set_timeout = tco_timer_set_timeout,
+};
 
-	/*
-	 * Check that the heartbeat value is within it's range.
-	 * If not, reset to the default.
-	 */
-	if (tco_timer_set_heartbeat(heartbeat)) {
-		heartbeat = WATCHDOG_HEARTBEAT;
-		tco_timer_set_heartbeat(heartbeat);
-	}
+static int sp5100_tco_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct watchdog_device *wdd;
+	struct sp5100_tco *tco;
+	int ret;
 
-	ret = misc_register(&sp5100_tco_miscdev);
-	if (ret != 0) {
-		pr_err("cannot register miscdev on minor=%d (err=%d)\n",
-		       WATCHDOG_MINOR, ret);
-		goto exit;
+	tco = devm_kzalloc(dev, sizeof(*tco), GFP_KERNEL);
+	if (!tco)
+		return -ENOMEM;
+
+	tco->tco_reg_layout = tco_reg_layout(sp5100_tco_pci);
+
+	wdd = &tco->wdd;
+	wdd->parent = dev;
+	wdd->info = &sp5100_tco_wdt_info;
+	wdd->ops = &sp5100_tco_wdt_ops;
+	wdd->timeout = WATCHDOG_HEARTBEAT;
+	wdd->min_timeout = 1;
+	wdd->max_timeout = 0xffff;
+
+	if (watchdog_init_timeout(wdd, heartbeat, NULL))
+		dev_info(dev, "timeout value invalid, using %d\n",
+			 wdd->timeout);
+	watchdog_set_nowayout(wdd, nowayout);
+	watchdog_stop_on_reboot(wdd);
+	watchdog_stop_on_unregister(wdd);
+	watchdog_set_drvdata(wdd, tco);
+
+	ret = sp5100_tco_setupdevice(dev, wdd);
+	if (ret)
+		return ret;
+
+	ret = devm_watchdog_register_device(dev, wdd);
+	if (ret) {
+		dev_err(dev, "cannot register watchdog device (err=%d)\n", ret);
+		return ret;
 	}
 
-	clear_bit(0, &timer_alive);
-
 	/* Show module parameters */
-	pr_info("initialized (0x%p). heartbeat=%d sec (nowayout=%d)\n",
-		tcobase, heartbeat, nowayout);
-
-	return 0;
-
-exit:
-	iounmap(tcobase);
-	release_mem_region(tcobase_phys, SP5100_WDT_MEM_MAP_SIZE);
-	release_region(pm_iobase, SP5100_PM_IOPORTS_SIZE);
-	return ret;
-}
-
-static void sp5100_tco_cleanup(void)
-{
-	/* Stop the timer before we leave */
-	if (!nowayout)
-		tco_timer_stop();
-
-	/* Deregister */
-	misc_deregister(&sp5100_tco_miscdev);
-	iounmap(tcobase);
-	release_mem_region(tcobase_phys, SP5100_WDT_MEM_MAP_SIZE);
-	release_region(pm_iobase, SP5100_PM_IOPORTS_SIZE);
-}
+	dev_info(dev, "initialized. heartbeat=%d sec (nowayout=%d)\n",
+		 wdd->timeout, nowayout);
 
-static int sp5100_tco_remove(struct platform_device *dev)
-{
-	if (tcobase)
-		sp5100_tco_cleanup();
 	return 0;
 }
 
-static void sp5100_tco_shutdown(struct platform_device *dev)
-{
-	tco_timer_stop();
-}
-
 static struct platform_driver sp5100_tco_driver = {
-	.probe		= sp5100_tco_init,
-	.remove		= sp5100_tco_remove,
-	.shutdown	= sp5100_tco_shutdown,
+	.probe		= sp5100_tco_probe,
 	.driver		= {
-		.name	= TCO_MODULE_NAME,
+		.name	= TCO_DRIVER_NAME,
 	},
 };
 
-static int __init sp5100_tco_init_module(void)
+/*
+ * Data for PCI driver interface
+ *
+ * This data only exists for exporting the supported
+ * PCI ids via MODULE_DEVICE_TABLE.  We do not actually
+ * register a pci_driver, because someone else might
+ * want to register another driver on the same PCI id.
+ */
+static const struct pci_device_id sp5100_tco_pci_tbl[] = {
+	{ PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS, PCI_ANY_ID,
+	  PCI_ANY_ID, },
+	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_HUDSON2_SMBUS, PCI_ANY_ID,
+	  PCI_ANY_ID, },
+	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_KERNCZ_SMBUS, PCI_ANY_ID,
+	  PCI_ANY_ID, },
+	{ 0, },			/* End of list */
+};
+MODULE_DEVICE_TABLE(pci, sp5100_tco_pci_tbl);
+
+static int __init sp5100_tco_init(void)
 {
+	struct pci_dev *dev = NULL;
 	int err;
 
-	pr_info("SP5100/SB800 TCO WatchDog Timer Driver v%s\n", TCO_VERSION);
+	/* Match the PCI device */
+	for_each_pci_dev(dev) {
+		if (pci_match_id(sp5100_tco_pci_tbl, dev) != NULL) {
+			sp5100_tco_pci = dev;
+			break;
+		}
+	}
+
+	if (!sp5100_tco_pci)
+		return -ENODEV;
+
+	pr_info("SP5100/SB800 TCO WatchDog Timer Driver\n");
 
 	err = platform_driver_register(&sp5100_tco_driver);
 	if (err)
 		return err;
 
-	sp5100_tco_platform_device = platform_device_register_simple(
-					TCO_MODULE_NAME, -1, NULL, 0);
+	sp5100_tco_platform_device =
+		platform_device_register_simple(TCO_DRIVER_NAME, -1, NULL, 0);
 	if (IS_ERR(sp5100_tco_platform_device)) {
 		err = PTR_ERR(sp5100_tco_platform_device);
 		goto unreg_platform_driver;
@@ -579,15 +482,14 @@ static int __init sp5100_tco_init_module(void)
 	return err;
 }
 
-static void __exit sp5100_tco_cleanup_module(void)
+static void __exit sp5100_tco_exit(void)
 {
 	platform_device_unregister(sp5100_tco_platform_device);
 	platform_driver_unregister(&sp5100_tco_driver);
-	pr_info("SP5100/SB800 TCO Watchdog Module Unloaded\n");
 }
 
-module_init(sp5100_tco_init_module);
-module_exit(sp5100_tco_cleanup_module);
+module_init(sp5100_tco_init);
+module_exit(sp5100_tco_exit);
 
 MODULE_AUTHOR("Priyanka Gupta");
 MODULE_DESCRIPTION("TCO timer driver for SP5100/SB800 chipset");

drivers/watchdog/sp5100_tco.h

@@ -7,6 +7,8 @@
  *	TCO timer driver for sp5100 chipsets
  */
 
+#include <linux/bitops.h>
+
 /*
  * Some address definitions for the Watchdog
  */
@@ -14,8 +16,11 @@
 #define SP5100_WDT_CONTROL(base)	((base) + 0x00) /* Watchdog Control */
 #define SP5100_WDT_COUNT(base)		((base) + 0x04) /* Watchdog Count */
 
-#define SP5100_WDT_START_STOP_BIT	(1 << 0)
-#define SP5100_WDT_TRIGGER_BIT		(1 << 7)
+#define SP5100_WDT_START_STOP_BIT	BIT(0)
+#define SP5100_WDT_FIRED		BIT(1)
+#define SP5100_WDT_ACTION_RESET		BIT(2)
+#define SP5100_WDT_DISABLED		BIT(3)
+#define SP5100_WDT_TRIGGER_BIT		BIT(7)
 
 #define SP5100_PM_IOPORTS_SIZE		0x02
 
@@ -24,43 +29,57 @@
  * read them from a register.
  */
 
-/*  For SP5100/SB7x0 chipset */
+/*  For SP5100/SB7x0/SB8x0 chipset */
 #define SP5100_IO_PM_INDEX_REG		0xCD6
 #define SP5100_IO_PM_DATA_REG		0xCD7
 
+/* For SP5100/SB7x0 chipset */
 #define SP5100_SB_RESOURCE_MMIO_BASE	0x9C
 
 #define SP5100_PM_WATCHDOG_CONTROL	0x69
 #define SP5100_PM_WATCHDOG_BASE		0x6C
 
-#define SP5100_PM_WATCHDOG_FIRED	(1 << 1)
-#define SP5100_PM_WATCHDOG_ACTION_RESET	(1 << 2)
-
 #define SP5100_PCI_WATCHDOG_MISC_REG	0x41
-#define SP5100_PCI_WATCHDOG_DECODE_EN	(1 << 3)
+#define SP5100_PCI_WATCHDOG_DECODE_EN	BIT(3)
 
-#define SP5100_PM_WATCHDOG_DISABLE	(1 << 0)
-#define SP5100_PM_WATCHDOG_SECOND_RES	(3 << 1)
+#define SP5100_PM_WATCHDOG_DISABLE	((u8)BIT(0))
+#define SP5100_PM_WATCHDOG_SECOND_RES	GENMASK(2, 1)
 
 #define SP5100_DEVNAME			"SP5100 TCO"
 
-
 /*  For SB8x0(or later) chipset */
-#define SB800_IO_PM_INDEX_REG		0xCD6
-#define SB800_IO_PM_DATA_REG		0xCD7
-
 #define SB800_PM_ACPI_MMIO_EN		0x24
 #define SB800_PM_WATCHDOG_CONTROL	0x48
 #define SB800_PM_WATCHDOG_BASE		0x48
 #define SB800_PM_WATCHDOG_CONFIG	0x4C
 
-#define SB800_PCI_WATCHDOG_DECODE_EN	(1 << 0)
-#define SB800_PM_WATCHDOG_DISABLE	(1 << 2)
-#define SB800_PM_WATCHDOG_SECOND_RES	(3 << 0)
-#define SB800_ACPI_MMIO_DECODE_EN	(1 << 0)
-#define SB800_ACPI_MMIO_SEL		(1 << 1)
-
+#define SB800_PCI_WATCHDOG_DECODE_EN	BIT(0)
+#define SB800_PM_WATCHDOG_DISABLE	((u8)BIT(1))
+#define SB800_PM_WATCHDOG_SECOND_RES	GENMASK(1, 0)
+#define SB800_ACPI_MMIO_DECODE_EN	BIT(0)
+#define SB800_ACPI_MMIO_SEL		BIT(1)
 
 #define SB800_PM_WDT_MMIO_OFFSET	0xB00
 
 #define SB800_DEVNAME			"SB800 TCO"
+
+/* For recent chips with embedded FCH (rev 40+) */
+
+#define EFCH_PM_DECODEEN		0x00
+
+#define EFCH_PM_DECODEEN_WDT_TMREN	BIT(7)
+
+
+#define EFCH_PM_DECODEEN3		0x00
+#define EFCH_PM_DECODEEN_SECOND_RES	GENMASK(1, 0)
+#define EFCH_PM_WATCHDOG_DISABLE	((u8)GENMASK(3, 2))
+
+/* WDT MMIO if enabled with PM00_DECODEEN_WDT_TMREN */
+#define EFCH_PM_WDT_ADDR		0xfeb00000
+
+#define EFCH_PM_ISACONTROL		0x04
+
+#define EFCH_PM_ISACONTROL_MMIOEN	BIT(1)
+
+#define EFCH_PM_ACPI_MMIO_ADDR		0xfed80000
+#define EFCH_PM_ACPI_MMIO_WDT_OFFSET	0x00000b00

drivers/watchdog/sprd_wdt.c

+/*
+ * Spreadtrum watchdog driver
+ * Copyright (C) 2017 Spreadtrum - http://www.spreadtrum.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/watchdog.h>
+
+#define SPRD_WDT_LOAD_LOW		0x0
+#define SPRD_WDT_LOAD_HIGH		0x4
+#define SPRD_WDT_CTRL			0x8
+#define SPRD_WDT_INT_CLR		0xc
+#define SPRD_WDT_INT_RAW		0x10
+#define SPRD_WDT_INT_MSK		0x14
+#define SPRD_WDT_CNT_LOW		0x18
+#define SPRD_WDT_CNT_HIGH		0x1c
+#define SPRD_WDT_LOCK			0x20
+#define SPRD_WDT_IRQ_LOAD_LOW		0x2c
+#define SPRD_WDT_IRQ_LOAD_HIGH		0x30
+
+/* WDT_CTRL */
+#define SPRD_WDT_INT_EN_BIT		BIT(0)
+#define SPRD_WDT_CNT_EN_BIT		BIT(1)
+#define SPRD_WDT_NEW_VER_EN		BIT(2)
+#define SPRD_WDT_RST_EN_BIT		BIT(3)
+
+/* WDT_INT_CLR */
+#define SPRD_WDT_INT_CLEAR_BIT		BIT(0)
+#define SPRD_WDT_RST_CLEAR_BIT		BIT(3)
+
+/* WDT_INT_RAW */
+#define SPRD_WDT_INT_RAW_BIT		BIT(0)
+#define SPRD_WDT_RST_RAW_BIT		BIT(3)
+#define SPRD_WDT_LD_BUSY_BIT		BIT(4)
+
+/* 1s equal to 32768 counter steps */
+#define SPRD_WDT_CNT_STEP		32768
+
+#define SPRD_WDT_UNLOCK_KEY		0xe551
+#define SPRD_WDT_MIN_TIMEOUT		3
+#define SPRD_WDT_MAX_TIMEOUT		60
+
+#define SPRD_WDT_CNT_HIGH_SHIFT		16
+#define SPRD_WDT_LOW_VALUE_MASK		GENMASK(15, 0)
+#define SPRD_WDT_LOAD_TIMEOUT		1000
+
+struct sprd_wdt {
+	void __iomem *base;
+	struct watchdog_device wdd;
+	struct clk *enable;
+	struct clk *rtc_enable;
+	int irq;
+};
+
+static inline struct sprd_wdt *to_sprd_wdt(struct watchdog_device *wdd)
+{
+	return container_of(wdd, struct sprd_wdt, wdd);
+}
+
+static inline void sprd_wdt_lock(void __iomem *addr)
+{
+	writel_relaxed(0x0, addr + SPRD_WDT_LOCK);
+}
+
+static inline void sprd_wdt_unlock(void __iomem *addr)
+{
+	writel_relaxed(SPRD_WDT_UNLOCK_KEY, addr + SPRD_WDT_LOCK);
+}
+
+static irqreturn_t sprd_wdt_isr(int irq, void *dev_id)
+{
+	struct sprd_wdt *wdt = (struct sprd_wdt *)dev_id;
+
+	sprd_wdt_unlock(wdt->base);
+	writel_relaxed(SPRD_WDT_INT_CLEAR_BIT, wdt->base + SPRD_WDT_INT_CLR);
+	sprd_wdt_lock(wdt->base);
+	watchdog_notify_pretimeout(&wdt->wdd);
+	return IRQ_HANDLED;
+}
+
+static u32 sprd_wdt_get_cnt_value(struct sprd_wdt *wdt)
+{
+	u32 val;
+
+	val = readl_relaxed(wdt->base + SPRD_WDT_CNT_HIGH) <<
+		SPRD_WDT_CNT_HIGH_SHIFT;
+	val |= readl_relaxed(wdt->base + SPRD_WDT_CNT_LOW) &
+		SPRD_WDT_LOW_VALUE_MASK;
+
+	return val;
+}
+
+static int sprd_wdt_load_value(struct sprd_wdt *wdt, u32 timeout,
+			       u32 pretimeout)
+{
+	u32 val, delay_cnt = 0;
+	u32 tmr_step = timeout * SPRD_WDT_CNT_STEP;
+	u32 prtmr_step = pretimeout * SPRD_WDT_CNT_STEP;
+
+	sprd_wdt_unlock(wdt->base);
+	writel_relaxed((tmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) &
+		      SPRD_WDT_LOW_VALUE_MASK, wdt->base + SPRD_WDT_LOAD_HIGH);
+	writel_relaxed((tmr_step & SPRD_WDT_LOW_VALUE_MASK),
+		       wdt->base + SPRD_WDT_LOAD_LOW);
+	writel_relaxed((prtmr_step >> SPRD_WDT_CNT_HIGH_SHIFT) &
+			SPRD_WDT_LOW_VALUE_MASK,
+		       wdt->base + SPRD_WDT_IRQ_LOAD_HIGH);
+	writel_relaxed(prtmr_step & SPRD_WDT_LOW_VALUE_MASK,
+		       wdt->base + SPRD_WDT_IRQ_LOAD_LOW);
+	sprd_wdt_lock(wdt->base);
+
+	/*
+	 * Waiting the load value operation done,
+	 * it needs two or three RTC clock cycles.
+	 */
+	do {
+		val = readl_relaxed(wdt->base + SPRD_WDT_INT_RAW);
+		if (!(val & SPRD_WDT_LD_BUSY_BIT))
+			break;
+
+		cpu_relax();
+	} while (delay_cnt++ < SPRD_WDT_LOAD_TIMEOUT);
+
+	if (delay_cnt >= SPRD_WDT_LOAD_TIMEOUT)
+		return -EBUSY;
+	return 0;
+}
+
+static int sprd_wdt_enable(struct sprd_wdt *wdt)
+{
+	u32 val;
+	int ret;
+
+	ret = clk_prepare_enable(wdt->enable);
+	if (ret)
+		return ret;
+	ret = clk_prepare_enable(wdt->rtc_enable);
+	if (ret)
+		return ret;
+
+	sprd_wdt_unlock(wdt->base);
+	val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
+	val |= SPRD_WDT_NEW_VER_EN;
+	writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
+	sprd_wdt_lock(wdt->base);
+	return 0;
+}
+
+static void sprd_wdt_disable(void *_data)
+{
+	struct sprd_wdt *wdt = _data;
+
+	sprd_wdt_unlock(wdt->base);
+	writel_relaxed(0x0, wdt->base + SPRD_WDT_CTRL);
+	sprd_wdt_lock(wdt->base);
+
+	clk_disable_unprepare(wdt->rtc_enable);
+	clk_disable_unprepare(wdt->enable);
+}
+
+static int sprd_wdt_start(struct watchdog_device *wdd)
+{
+	struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+	u32 val;
+	int ret;
+
+	ret = sprd_wdt_load_value(wdt, wdd->timeout, wdd->pretimeout);
+	if (ret)
+		return ret;
+
+	sprd_wdt_unlock(wdt->base);
+	val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
+	val |= SPRD_WDT_CNT_EN_BIT | SPRD_WDT_INT_EN_BIT | SPRD_WDT_RST_EN_BIT;
+	writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
+	sprd_wdt_lock(wdt->base);
+	set_bit(WDOG_HW_RUNNING, &wdd->status);
+
+	return 0;
+}
+
+static int sprd_wdt_stop(struct watchdog_device *wdd)
+{
+	struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+	u32 val;
+
+	sprd_wdt_unlock(wdt->base);
+	val = readl_relaxed(wdt->base + SPRD_WDT_CTRL);
+	val &= ~(SPRD_WDT_CNT_EN_BIT | SPRD_WDT_RST_EN_BIT |
+		SPRD_WDT_INT_EN_BIT);
+	writel_relaxed(val, wdt->base + SPRD_WDT_CTRL);
+	sprd_wdt_lock(wdt->base);
+	return 0;
+}
+
+static int sprd_wdt_set_timeout(struct watchdog_device *wdd,
+				u32 timeout)
+{
+	struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+
+	if (timeout == wdd->timeout)
+		return 0;
+
+	wdd->timeout = timeout;
+
+	return sprd_wdt_load_value(wdt, timeout, wdd->pretimeout);
+}
+
+static int sprd_wdt_set_pretimeout(struct watchdog_device *wdd,
+				   u32 new_pretimeout)
+{
+	struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+
+	if (new_pretimeout < wdd->min_timeout)
+		return -EINVAL;
+
+	wdd->pretimeout = new_pretimeout;
+
+	return sprd_wdt_load_value(wdt, wdd->timeout, new_pretimeout);
+}
+
+static u32 sprd_wdt_get_timeleft(struct watchdog_device *wdd)
+{
+	struct sprd_wdt *wdt = to_sprd_wdt(wdd);
+	u32 val;
+
+	val = sprd_wdt_get_cnt_value(wdt);
+	val = val / SPRD_WDT_CNT_STEP;
+
+	return val;
+}
+
+static const struct watchdog_ops sprd_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = sprd_wdt_start,
+	.stop = sprd_wdt_stop,
+	.set_timeout = sprd_wdt_set_timeout,
+	.set_pretimeout = sprd_wdt_set_pretimeout,
+	.get_timeleft = sprd_wdt_get_timeleft,
+};
+
+static const struct watchdog_info sprd_wdt_info = {
+	.options = WDIOF_SETTIMEOUT |
+		   WDIOF_PRETIMEOUT |
+		   WDIOF_MAGICCLOSE |
+		   WDIOF_KEEPALIVEPING,
+	.identity = "Spreadtrum Watchdog Timer",
+};
+
+static int sprd_wdt_probe(struct platform_device *pdev)
+{
+	struct resource *wdt_res;
+	struct sprd_wdt *wdt;
+	int ret;
+
+	wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
+	if (!wdt)
+		return -ENOMEM;
+
+	wdt_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	wdt->base = devm_ioremap_resource(&pdev->dev, wdt_res);
+	if (IS_ERR(wdt->base)) {
+		dev_err(&pdev->dev, "failed to map memory resource\n");
+		return PTR_ERR(wdt->base);
+	}
+
+	wdt->enable = devm_clk_get(&pdev->dev, "enable");
+	if (IS_ERR(wdt->enable)) {
+		dev_err(&pdev->dev, "can't get the enable clock\n");
+		return PTR_ERR(wdt->enable);
+	}
+
+	wdt->rtc_enable = devm_clk_get(&pdev->dev, "rtc_enable");
+	if (IS_ERR(wdt->rtc_enable)) {
+		dev_err(&pdev->dev, "can't get the rtc enable clock\n");
+		return PTR_ERR(wdt->rtc_enable);
+	}
+
+	wdt->irq = platform_get_irq(pdev, 0);
+	if (wdt->irq < 0) {
+		dev_err(&pdev->dev, "failed to get IRQ resource\n");
+		return wdt->irq;
+	}
+
+	ret = devm_request_irq(&pdev->dev, wdt->irq, sprd_wdt_isr,
+			       IRQF_NO_SUSPEND, "sprd-wdt", (void *)wdt);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register irq\n");
+		return ret;
+	}
+
+	wdt->wdd.info = &sprd_wdt_info;
+	wdt->wdd.ops = &sprd_wdt_ops;
+	wdt->wdd.parent = &pdev->dev;
+	wdt->wdd.min_timeout = SPRD_WDT_MIN_TIMEOUT;
+	wdt->wdd.max_timeout = SPRD_WDT_MAX_TIMEOUT;
+	wdt->wdd.timeout = SPRD_WDT_MAX_TIMEOUT;
+
+	ret = sprd_wdt_enable(wdt);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to enable wdt\n");
+		return ret;
+	}
+	ret = devm_add_action(&pdev->dev, sprd_wdt_disable, wdt);
+	if (ret) {
+		sprd_wdt_disable(wdt);
+		dev_err(&pdev->dev, "Failed to add wdt disable action\n");
+		return ret;
+	}
+
+	watchdog_set_nowayout(&wdt->wdd, WATCHDOG_NOWAYOUT);
+	watchdog_init_timeout(&wdt->wdd, 0, &pdev->dev);
+
+	ret = devm_watchdog_register_device(&pdev->dev, &wdt->wdd);
+	if (ret) {
+		sprd_wdt_disable(wdt);
+		dev_err(&pdev->dev, "failed to register watchdog\n");
+		return ret;
+	}
+	platform_set_drvdata(pdev, wdt);
+
+	return 0;
+}
+
+static int __maybe_unused sprd_wdt_pm_suspend(struct device *dev)
+{
+	struct watchdog_device *wdd = dev_get_drvdata(dev);
+	struct sprd_wdt *wdt = dev_get_drvdata(dev);
+
+	if (watchdog_active(wdd))
+		sprd_wdt_stop(&wdt->wdd);
+	sprd_wdt_disable(wdt);
+
+	return 0;
+}
+
+static int __maybe_unused sprd_wdt_pm_resume(struct device *dev)
+{
+	struct watchdog_device *wdd = dev_get_drvdata(dev);
+	struct sprd_wdt *wdt = dev_get_drvdata(dev);
+	int ret;
+
+	ret = sprd_wdt_enable(wdt);
+	if (ret)
+		return ret;
+
+	if (watchdog_active(wdd)) {
+		ret = sprd_wdt_start(&wdt->wdd);
+		if (ret) {
+			sprd_wdt_disable(wdt);
+			return ret;
+		}
+	}
+
+	return 0;
+}
+
+static const struct dev_pm_ops sprd_wdt_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(sprd_wdt_pm_suspend,
+				sprd_wdt_pm_resume)
+};
+
+static const struct of_device_id sprd_wdt_match_table[] = {
+	{ .compatible = "sprd,sp9860-wdt", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, sprd_wdt_match_table);
+
+static struct platform_driver sprd_watchdog_driver = {
+	.probe	= sprd_wdt_probe,
+	.driver	= {
+		.name = "sprd-wdt",
+		.of_match_table = sprd_wdt_match_table,
+		.pm = &sprd_wdt_pm_ops,
+	},
+};
+module_platform_driver(sprd_watchdog_driver);
+
+MODULE_AUTHOR("Eric Long <eric.long@spreadtrum.com>");
+MODULE_DESCRIPTION("Spreadtrum Watchdog Timer Controller Driver");
+MODULE_LICENSE("GPL v2");

drivers/watchdog/stm32_iwdg.c

+// SPDX-License-Identifier: GPL-2.0
 /*
  * Driver for STM32 Independent Watchdog
  *
- * Copyright (C) Yannick Fertre 2017
- * Author: Yannick Fertre <yannick.fertre@st.com>
+ * Copyright (C) STMicroelectronics 2017
+ * Author: Yannick Fertre <yannick.fertre@st.com> for STMicroelectronics.
  *
  * This driver is based on tegra_wdt.c
  *
- * License terms:  GNU General Public License (GPL), version 2
  */
 
 #include <linux/clk.h>

drivers/watchdog/sunxi_wdt.c

@@ -234,7 +234,6 @@ MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids);
 static int sunxi_wdt_probe(struct platform_device *pdev)
 {
 	struct sunxi_wdt_dev *sunxi_wdt;
-	const struct of_device_id *device;
 	struct resource *res;
 	int err;
 
@@ -242,12 +241,10 @@ static int sunxi_wdt_probe(struct platform_device *pdev)
 	if (!sunxi_wdt)
 		return -EINVAL;
 
-	device = of_match_device(sunxi_wdt_dt_ids, &pdev->dev);
-	if (!device)
+	sunxi_wdt->wdt_regs = of_device_get_match_data(&pdev->dev);
+	if (!sunxi_wdt->wdt_regs)
 		return -ENODEV;
 
-	sunxi_wdt->wdt_regs = device->data;
-
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 	sunxi_wdt->wdt_base = devm_ioremap_resource(&pdev->dev, res);
 	if (IS_ERR(sunxi_wdt->wdt_base))

drivers/watchdog/watchdog_core.c

@@ -97,6 +97,7 @@ static void watchdog_check_min_max_timeout(struct watchdog_device *wdd)
 
 /**
  * watchdog_init_timeout() - initialize the timeout field
+ * @wdd: watchdog device
  * @timeout_parm: timeout module parameter
  * @dev: Device that stores the timeout-sec property
  *

drivers/watchdog/watchdog_dev.c

@@ -36,9 +36,10 @@
 #include <linux/errno.h>	/* For the -ENODEV/... values */
 #include <linux/fs.h>		/* For file operations */
 #include <linux/init.h>		/* For __init/__exit/... */
-#include <linux/jiffies.h>	/* For timeout functions */
+#include <linux/hrtimer.h>	/* For hrtimers */
 #include <linux/kernel.h>	/* For printk/panic/... */
 #include <linux/kref.h>		/* For data references */
+#include <linux/kthread.h>	/* For kthread_work */
 #include <linux/miscdevice.h>	/* For handling misc devices */
 #include <linux/module.h>	/* For module stuff/... */
 #include <linux/mutex.h>	/* For mutexes */
@@ -46,9 +47,10 @@
 #include <linux/slab.h>		/* For memory functions */
 #include <linux/types.h>	/* For standard types (like size_t) */
 #include <linux/watchdog.h>	/* For watchdog specific items */
-#include <linux/workqueue.h>	/* For workqueue */
 #include <linux/uaccess.h>	/* For copy_to_user/put_user/... */
 
+#include <uapi/linux/sched/types.h>	/* For struct sched_param */
+
 #include "watchdog_core.h"
 #include "watchdog_pretimeout.h"
 
@@ -65,9 +67,10 @@ struct watchdog_core_data {
 	struct cdev cdev;
 	struct watchdog_device *wdd;
 	struct mutex lock;
-	unsigned long last_keepalive;
-	unsigned long last_hw_keepalive;
-	struct delayed_work work;
+	ktime_t last_keepalive;
+	ktime_t last_hw_keepalive;
+	struct hrtimer timer;
+	struct kthread_work work;
 	unsigned long status;		/* Internal status bits */
 #define _WDOG_DEV_OPEN		0	/* Opened ? */
 #define _WDOG_ALLOW_RELEASE	1	/* Did we receive the magic char ? */
@@ -79,7 +82,7 @@ static dev_t watchdog_devt;
 /* Reference to watchdog device behind /dev/watchdog */
 static struct watchdog_core_data *old_wd_data;
 
-static struct workqueue_struct *watchdog_wq;
+static struct kthread_worker *watchdog_kworker;
 
 static bool handle_boot_enabled =
 	IS_ENABLED(CONFIG_WATCHDOG_HANDLE_BOOT_ENABLED);
@@ -107,18 +110,19 @@ static inline bool watchdog_need_worker(struct watchdog_device *wdd)
 		(t && !watchdog_active(wdd) && watchdog_hw_running(wdd));
 }
 
-static long watchdog_next_keepalive(struct watchdog_device *wdd)
+static ktime_t watchdog_next_keepalive(struct watchdog_device *wdd)
 {
 	struct watchdog_core_data *wd_data = wdd->wd_data;
 	unsigned int timeout_ms = wdd->timeout * 1000;
-	unsigned long keepalive_interval;
-	unsigned long last_heartbeat;
-	unsigned long virt_timeout;
+	ktime_t keepalive_interval;
+	ktime_t last_heartbeat, latest_heartbeat;
+	ktime_t virt_timeout;
 	unsigned int hw_heartbeat_ms;
 
-	virt_timeout = wd_data->last_keepalive + msecs_to_jiffies(timeout_ms);
+	virt_timeout = ktime_add(wd_data->last_keepalive,
+				 ms_to_ktime(timeout_ms));
 	hw_heartbeat_ms = min_not_zero(timeout_ms, wdd->max_hw_heartbeat_ms);
-	keepalive_interval = msecs_to_jiffies(hw_heartbeat_ms / 2);
+	keepalive_interval = ms_to_ktime(hw_heartbeat_ms / 2);
 
 	if (!watchdog_active(wdd))
 		return keepalive_interval;
@@ -128,8 +132,11 @@ static long watchdog_next_keepalive(struct watchdog_device *wdd)
 	 * after the most recent ping from userspace, the last
 	 * worker ping has to come in hw_heartbeat_ms before this timeout.
 	 */
-	last_heartbeat = virt_timeout - msecs_to_jiffies(hw_heartbeat_ms);
-	return min_t(long, last_heartbeat - jiffies, keepalive_interval);
+	last_heartbeat = ktime_sub(virt_timeout, ms_to_ktime(hw_heartbeat_ms));
+	latest_heartbeat = ktime_sub(last_heartbeat, ktime_get());
+	if (ktime_before(latest_heartbeat, keepalive_interval))
+		return latest_heartbeat;
+	return keepalive_interval;
 }
 
 static inline void watchdog_update_worker(struct watchdog_device *wdd)
@@ -137,29 +144,33 @@ static inline void watchdog_update_worker(struct watchdog_device *wdd)
 	struct watchdog_core_data *wd_data = wdd->wd_data;
 
 	if (watchdog_need_worker(wdd)) {
-		long t = watchdog_next_keepalive(wdd);
+		ktime_t t = watchdog_next_keepalive(wdd);
 
 		if (t > 0)
-			mod_delayed_work(watchdog_wq, &wd_data->work, t);
+			hrtimer_start(&wd_data->timer, t, HRTIMER_MODE_REL);
 	} else {
-		cancel_delayed_work(&wd_data->work);
+		hrtimer_cancel(&wd_data->timer);
 	}
 }
 
 static int __watchdog_ping(struct watchdog_device *wdd)
 {
 	struct watchdog_core_data *wd_data = wdd->wd_data;
-	unsigned long earliest_keepalive = wd_data->last_hw_keepalive +
-				msecs_to_jiffies(wdd->min_hw_heartbeat_ms);
+	ktime_t earliest_keepalive, now;
 	int err;
 
-	if (time_is_after_jiffies(earliest_keepalive)) {
-		mod_delayed_work(watchdog_wq, &wd_data->work,
-				 earliest_keepalive - jiffies);
+	earliest_keepalive = ktime_add(wd_data->last_hw_keepalive,
+				       ms_to_ktime(wdd->min_hw_heartbeat_ms));
+	now = ktime_get();
+
+	if (ktime_after(earliest_keepalive, now)) {
+		hrtimer_start(&wd_data->timer,
+			      ktime_sub(earliest_keepalive, now),
+			      HRTIMER_MODE_REL);
 		return 0;
 	}
 
-	wd_data->last_hw_keepalive = jiffies;
+	wd_data->last_hw_keepalive = now;
 
 	if (wdd->ops->ping)
 		err = wdd->ops->ping(wdd);  /* ping the watchdog */
@@ -192,7 +203,7 @@ static int watchdog_ping(struct watchdog_device *wdd)
 
 	set_bit(_WDOG_KEEPALIVE, &wd_data->status);
 
-	wd_data->last_keepalive = jiffies;
+	wd_data->last_keepalive = ktime_get();
 	return __watchdog_ping(wdd);
 }
 
@@ -203,12 +214,11 @@ static bool watchdog_worker_should_ping(struct watchdog_core_data *wd_data)
 	return wdd && (watchdog_active(wdd) || watchdog_hw_running(wdd));
 }
 
-static void watchdog_ping_work(struct work_struct *work)
+static void watchdog_ping_work(struct kthread_work *work)
 {
 	struct watchdog_core_data *wd_data;
 
-	wd_data = container_of(to_delayed_work(work), struct watchdog_core_data,
-			       work);
+	wd_data = container_of(work, struct watchdog_core_data, work);
 
 	mutex_lock(&wd_data->lock);
 	if (watchdog_worker_should_ping(wd_data))
@@ -216,6 +226,16 @@ static void watchdog_ping_work(struct work_struct *work)
 	mutex_unlock(&wd_data->lock);
 }
 
+static enum hrtimer_restart watchdog_timer_expired(struct hrtimer *timer)
+{
+	struct watchdog_core_data *wd_data;
+
+	wd_data = container_of(timer, struct watchdog_core_data, timer);
+
+	kthread_queue_work(watchdog_kworker, &wd_data->work);
+	return HRTIMER_NORESTART;
+}
+
 /*
  *	watchdog_start: wrapper to start the watchdog.
  *	@wdd: the watchdog device to start
@@ -230,7 +250,7 @@ static void watchdog_ping_work(struct work_struct *work)
 static int watchdog_start(struct watchdog_device *wdd)
 {
 	struct watchdog_core_data *wd_data = wdd->wd_data;
-	unsigned long started_at;
+	ktime_t started_at;
 	int err;
 
 	if (watchdog_active(wdd))
@@ -238,7 +258,7 @@ static int watchdog_start(struct watchdog_device *wdd)
 
 	set_bit(_WDOG_KEEPALIVE, &wd_data->status);
 
-	started_at = jiffies;
+	started_at = ktime_get();
 	if (watchdog_hw_running(wdd) && wdd->ops->ping)
 		err = wdd->ops->ping(wdd);
 	else
@@ -720,7 +740,7 @@ static long watchdog_ioctl(struct file *file, unsigned int cmd,
 		err = watchdog_ping(wdd);
 		if (err < 0)
 			break;
-		/* Fall */
+		/* fall through */
 	case WDIOC_GETTIMEOUT:
 		/* timeout == 0 means that we don't know the timeout */
 		if (wdd->timeout == 0) {
@@ -769,6 +789,7 @@ static int watchdog_open(struct inode *inode, struct file *file)
 {
 	struct watchdog_core_data *wd_data;
 	struct watchdog_device *wdd;
+	bool hw_running;
 	int err;
 
 	/* Get the corresponding watchdog device */
@@ -788,7 +809,8 @@ static int watchdog_open(struct inode *inode, struct file *file)
 	 * If the /dev/watchdog device is open, we don't want the module
 	 * to be unloaded.
 	 */
-	if (!watchdog_hw_running(wdd) && !try_module_get(wdd->ops->owner)) {
+	hw_running = watchdog_hw_running(wdd);
+	if (!hw_running && !try_module_get(wdd->ops->owner)) {
 		err = -EBUSY;
 		goto out_clear;
 	}
@@ -799,7 +821,7 @@ static int watchdog_open(struct inode *inode, struct file *file)
 
 	file->private_data = wd_data;
 
-	if (!watchdog_hw_running(wdd))
+	if (!hw_running)
 		kref_get(&wd_data->kref);
 
 	/* dev/watchdog is a virtual (and thus non-seekable) filesystem */
@@ -919,10 +941,12 @@ static int watchdog_cdev_register(struct watchdog_device *wdd, dev_t devno)
 	wd_data->wdd = wdd;
 	wdd->wd_data = wd_data;
 
-	if (!watchdog_wq)
+	if (IS_ERR_OR_NULL(watchdog_kworker))
 		return -ENODEV;
 
-	INIT_DELAYED_WORK(&wd_data->work, watchdog_ping_work);
+	kthread_init_work(&wd_data->work, watchdog_ping_work);
+	hrtimer_init(&wd_data->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	wd_data->timer.function = watchdog_timer_expired;
 
 	if (wdd->id == 0) {
 		old_wd_data = wd_data;
@@ -958,21 +982,20 @@ static int watchdog_cdev_register(struct watchdog_device *wdd, dev_t devno)
 	}
 
 	/* Record time of most recent heartbeat as 'just before now'. */
-	wd_data->last_hw_keepalive = jiffies - 1;
+	wd_data->last_hw_keepalive = ktime_sub(ktime_get(), 1);
 
 	/*
 	 * If the watchdog is running, prevent its driver from being unloaded,
 	 * and schedule an immediate ping.
 	 */
 	if (watchdog_hw_running(wdd)) {
-		if (handle_boot_enabled) {
-			__module_get(wdd->ops->owner);
-			kref_get(&wd_data->kref);
-			queue_delayed_work(watchdog_wq, &wd_data->work, 0);
-		} else {
+		__module_get(wdd->ops->owner);
+		kref_get(&wd_data->kref);
+		if (handle_boot_enabled)
+			hrtimer_start(&wd_data->timer, 0, HRTIMER_MODE_REL);
+		else
 			pr_info("watchdog%d running and kernel based pre-userspace handler disabled\n",
-					wdd->id);
-		}
+				wdd->id);
 	}
 
 	return 0;
@@ -1006,7 +1029,8 @@ static void watchdog_cdev_unregister(struct watchdog_device *wdd)
 		watchdog_stop(wdd);
 	}
 
-	cancel_delayed_work_sync(&wd_data->work);
+	hrtimer_cancel(&wd_data->timer);
+	kthread_cancel_work_sync(&wd_data->work);
 
 	kref_put(&wd_data->kref, watchdog_core_data_release);
 }
@@ -1110,13 +1134,14 @@ void watchdog_dev_unregister(struct watchdog_device *wdd)
 int __init watchdog_dev_init(void)
 {
 	int err;
+	struct sched_param param = {.sched_priority = MAX_RT_PRIO - 1,};
 
-	watchdog_wq = alloc_workqueue("watchdogd",
-				      WQ_HIGHPRI | WQ_MEM_RECLAIM, 0);
-	if (!watchdog_wq) {
-		pr_err("Failed to create watchdog workqueue\n");
-		return -ENOMEM;
+	watchdog_kworker = kthread_create_worker(0, "watchdogd");
+	if (IS_ERR(watchdog_kworker)) {
+		pr_err("Failed to create watchdog kworker\n");
+		return PTR_ERR(watchdog_kworker);
 	}
+	sched_setscheduler(watchdog_kworker->task, SCHED_FIFO, &param);
 
 	err = class_register(&watchdog_class);
 	if (err < 0) {
@@ -1135,7 +1160,7 @@ int __init watchdog_dev_init(void)
 err_alloc:
 	class_unregister(&watchdog_class);
 err_register:
-	destroy_workqueue(watchdog_wq);
+	kthread_destroy_worker(watchdog_kworker);
 	return err;
 }
 
@@ -1149,7 +1174,7 @@ void __exit watchdog_dev_exit(void)
 {
 	unregister_chrdev_region(watchdog_devt, MAX_DOGS);
 	class_unregister(&watchdog_class);
-	destroy_workqueue(watchdog_wq);
+	kthread_destroy_worker(watchdog_kworker);
 }
 
 module_param(handle_boot_enabled, bool, 0444);

drivers/watchdog/wdt_pci.c

@@ -430,7 +430,7 @@ static long wdtpci_ioctl(struct file *file, unsigned int cmd,
 		if (wdtpci_set_heartbeat(new_heartbeat))
 			return -EINVAL;
 		wdtpci_ping();
-		/* Fall */
+		/* fall through */
 	case WDIOC_GETTIMEOUT:
 		return put_user(heartbeat, p);
 	default:

drivers/watchdog/xen_wdt.c

@@ -9,10 +9,7 @@
  *	2 of the License, or (at your option) any later version.
  */
 
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#define DRV_NAME	"wdt"
-#define DRV_VERSION	"0.01"
+#define DRV_NAME	"xen_wdt"
 
 #include <linux/bug.h>
 #include <linux/errno.h>
@@ -21,25 +18,20 @@
 #include <linux/kernel.h>
 #include <linux/ktime.h>
 #include <linux/init.h>
-#include <linux/miscdevice.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/platform_device.h>
-#include <linux/spinlock.h>
-#include <linux/uaccess.h>
 #include <linux/watchdog.h>
 #include <xen/xen.h>
 #include <asm/xen/hypercall.h>
 #include <xen/interface/sched.h>
 
 static struct platform_device *platform_device;
-static DEFINE_SPINLOCK(wdt_lock);
 static struct sched_watchdog wdt;
-static __kernel_time_t wdt_expires;
-static bool is_active, expect_release;
+static time64_t wdt_expires;
 
 #define WATCHDOG_TIMEOUT 60 /* in seconds */
-static unsigned int timeout = WATCHDOG_TIMEOUT;
+static unsigned int timeout;
 module_param(timeout, uint, S_IRUGO);
 MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds "
 	"(default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
@@ -49,20 +41,18 @@ module_param(nowayout, bool, S_IRUGO);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
 	"(default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
-static inline __kernel_time_t set_timeout(void)
+static inline time64_t set_timeout(struct watchdog_device *wdd)
 {
-	wdt.timeout = timeout;
-	return ktime_to_timespec(ktime_get()).tv_sec + timeout;
+	wdt.timeout = wdd->timeout;
+	return ktime_get_seconds() + wdd->timeout;
 }
 
-static int xen_wdt_start(void)
+static int xen_wdt_start(struct watchdog_device *wdd)
 {
-	__kernel_time_t expires;
+	time64_t expires;
 	int err;
 
-	spin_lock(&wdt_lock);
-
-	expires = set_timeout();
+	expires = set_timeout(wdd);
 	if (!wdt.id)
 		err = HYPERVISOR_sched_op(SCHEDOP_watchdog, &wdt);
 	else
@@ -74,36 +64,28 @@ static int xen_wdt_start(void)
 	} else
 		BUG_ON(!err);
 
-	spin_unlock(&wdt_lock);
-
 	return err;
 }
 
-static int xen_wdt_stop(void)
+static int xen_wdt_stop(struct watchdog_device *wdd)
 {
 	int err = 0;
 
-	spin_lock(&wdt_lock);
-
 	wdt.timeout = 0;
 	if (wdt.id)
 		err = HYPERVISOR_sched_op(SCHEDOP_watchdog, &wdt);
 	if (!err)
 		wdt.id = 0;
 
-	spin_unlock(&wdt_lock);
-
 	return err;
 }
 
-static int xen_wdt_kick(void)
+static int xen_wdt_kick(struct watchdog_device *wdd)
 {
-	__kernel_time_t expires;
+	time64_t expires;
 	int err;
 
-	spin_lock(&wdt_lock);
-
-	expires = set_timeout();
+	expires = set_timeout(wdd);
 	if (wdt.id)
 		err = HYPERVISOR_sched_op(SCHEDOP_watchdog, &wdt);
 	else
@@ -111,195 +93,72 @@ static int xen_wdt_kick(void)
 	if (!err)
 		wdt_expires = expires;
 
-	spin_unlock(&wdt_lock);
-
-	return err;
-}
-
-static int xen_wdt_open(struct inode *inode, struct file *file)
-{
-	int err;
-
-	/* /dev/watchdog can only be opened once */
-	if (xchg(&is_active, true))
-		return -EBUSY;
-
-	err = xen_wdt_start();
-	if (err == -EBUSY)
-		err = xen_wdt_kick();
-	return err ?: nonseekable_open(inode, file);
-}
-
-static int xen_wdt_release(struct inode *inode, struct file *file)
-{
-	int err = 0;
-
-	if (expect_release)
-		err = xen_wdt_stop();
-	else {
-		pr_crit("unexpected close, not stopping watchdog!\n");
-		xen_wdt_kick();
-	}
-	is_active = err;
-	expect_release = false;
 	return err;
 }
 
-static ssize_t xen_wdt_write(struct file *file, const char __user *data,
-			     size_t len, loff_t *ppos)
+static unsigned int xen_wdt_get_timeleft(struct watchdog_device *wdd)
 {
-	/* See if we got the magic character 'V' and reload the timer */
-	if (len) {
-		if (!nowayout) {
-			size_t i;
-
-			/* in case it was set long ago */
-			expect_release = false;
-
-			/* scan to see whether or not we got the magic
-			   character */
-			for (i = 0; i != len; i++) {
-				char c;
-				if (get_user(c, data + i))
-					return -EFAULT;
-				if (c == 'V')
-					expect_release = true;
-			}
-		}
-
-		/* someone wrote to us, we should reload the timer */
-		xen_wdt_kick();
-	}
-	return len;
+	return wdt_expires - ktime_get_seconds();
 }
 
-static long xen_wdt_ioctl(struct file *file, unsigned int cmd,
-			  unsigned long arg)
-{
-	int new_options, retval = -EINVAL;
-	int new_timeout;
-	int __user *argp = (void __user *)arg;
-	static const struct watchdog_info ident = {
-		.options =		WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,
-		.firmware_version =	0,
-		.identity =		DRV_NAME,
-	};
-
-	switch (cmd) {
-	case WDIOC_GETSUPPORT:
-		return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
-
-	case WDIOC_GETSTATUS:
-	case WDIOC_GETBOOTSTATUS:
-		return put_user(0, argp);
-
-	case WDIOC_SETOPTIONS:
-		if (get_user(new_options, argp))
-			return -EFAULT;
-
-		if (new_options & WDIOS_DISABLECARD)
-			retval = xen_wdt_stop();
-		if (new_options & WDIOS_ENABLECARD) {
-			retval = xen_wdt_start();
-			if (retval == -EBUSY)
-				retval = xen_wdt_kick();
-		}
-		return retval;
-
-	case WDIOC_KEEPALIVE:
-		xen_wdt_kick();
-		return 0;
-
-	case WDIOC_SETTIMEOUT:
-		if (get_user(new_timeout, argp))
-			return -EFAULT;
-		if (!new_timeout)
-			return -EINVAL;
-		timeout = new_timeout;
-		xen_wdt_kick();
-		/* fall through */
-	case WDIOC_GETTIMEOUT:
-		return put_user(timeout, argp);
-
-	case WDIOC_GETTIMELEFT:
-		retval = wdt_expires - ktime_to_timespec(ktime_get()).tv_sec;
-		return put_user(retval, argp);
-	}
-
-	return -ENOTTY;
-}
+static struct watchdog_info xen_wdt_info = {
+	.identity = DRV_NAME,
+	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
+};
 
-static const struct file_operations xen_wdt_fops = {
-	.owner =		THIS_MODULE,
-	.llseek =		no_llseek,
-	.write =		xen_wdt_write,
-	.unlocked_ioctl =	xen_wdt_ioctl,
-	.open =			xen_wdt_open,
-	.release =		xen_wdt_release,
+static const struct watchdog_ops xen_wdt_ops = {
+	.owner = THIS_MODULE,
+	.start = xen_wdt_start,
+	.stop = xen_wdt_stop,
+	.ping = xen_wdt_kick,
+	.get_timeleft = xen_wdt_get_timeleft,
 };
 
-static struct miscdevice xen_wdt_miscdev = {
-	.minor =	WATCHDOG_MINOR,
-	.name =		"watchdog",
-	.fops =		&xen_wdt_fops,
+static struct watchdog_device xen_wdt_dev = {
+	.info = &xen_wdt_info,
+	.ops = &xen_wdt_ops,
+	.timeout = WATCHDOG_TIMEOUT,
 };
 
-static int xen_wdt_probe(struct platform_device *dev)
+static int xen_wdt_probe(struct platform_device *pdev)
 {
 	struct sched_watchdog wd = { .id = ~0 };
 	int ret = HYPERVISOR_sched_op(SCHEDOP_watchdog, &wd);
 
-	switch (ret) {
-	case -EINVAL:
-		if (!timeout) {
-			timeout = WATCHDOG_TIMEOUT;
-			pr_info("timeout value invalid, using %d\n", timeout);
-		}
-
-		ret = misc_register(&xen_wdt_miscdev);
-		if (ret) {
-			pr_err("cannot register miscdev on minor=%d (%d)\n",
-			       WATCHDOG_MINOR, ret);
-			break;
-		}
-
-		pr_info("initialized (timeout=%ds, nowayout=%d)\n",
-			timeout, nowayout);
-		break;
-
-	case -ENOSYS:
-		pr_info("not supported\n");
-		ret = -ENODEV;
-		break;
-
-	default:
-		pr_info("bogus return value %d\n", ret);
-		break;
+	if (ret == -ENOSYS) {
+		dev_err(&pdev->dev, "watchdog not supported by hypervisor\n");
+		return -ENODEV;
 	}
 
-	return ret;
-}
+	if (ret != -EINVAL) {
+		dev_err(&pdev->dev, "unexpected hypervisor error (%d)\n", ret);
+		return -ENODEV;
+	}
 
-static int xen_wdt_remove(struct platform_device *dev)
-{
-	/* Stop the timer before we leave */
-	if (!nowayout)
-		xen_wdt_stop();
+	if (watchdog_init_timeout(&xen_wdt_dev, timeout, NULL))
+		dev_info(&pdev->dev, "timeout value invalid, using %d\n",
+			xen_wdt_dev.timeout);
+	watchdog_set_nowayout(&xen_wdt_dev, nowayout);
+	watchdog_stop_on_reboot(&xen_wdt_dev);
+	watchdog_stop_on_unregister(&xen_wdt_dev);
+
+	ret = devm_watchdog_register_device(&pdev->dev, &xen_wdt_dev);
+	if (ret) {
+		dev_err(&pdev->dev, "cannot register watchdog device (%d)\n",
+			ret);
+		return ret;
+	}
 
-	misc_deregister(&xen_wdt_miscdev);
+	dev_info(&pdev->dev, "initialized (timeout=%ds, nowayout=%d)\n",
+		xen_wdt_dev.timeout, nowayout);
 
 	return 0;
 }
 
-static void xen_wdt_shutdown(struct platform_device *dev)
-{
-	xen_wdt_stop();
-}
-
 static int xen_wdt_suspend(struct platform_device *dev, pm_message_t state)
 {
 	typeof(wdt.id) id = wdt.id;
-	int rc = xen_wdt_stop();
+	int rc = xen_wdt_stop(&xen_wdt_dev);
 
 	wdt.id = id;
 	return rc;
@@ -310,13 +169,11 @@ static int xen_wdt_resume(struct platform_device *dev)
 	if (!wdt.id)
 		return 0;
 	wdt.id = 0;
-	return xen_wdt_start();
+	return xen_wdt_start(&xen_wdt_dev);
 }
 
 static struct platform_driver xen_wdt_driver = {
 	.probe          = xen_wdt_probe,
-	.remove         = xen_wdt_remove,
-	.shutdown       = xen_wdt_shutdown,
 	.suspend        = xen_wdt_suspend,
 	.resume         = xen_wdt_resume,
 	.driver         = {
@@ -331,8 +188,6 @@ static int __init xen_wdt_init_module(void)
 	if (!xen_domain())
 		return -ENODEV;
 
-	pr_info("Xen WatchDog Timer Driver v%s\n", DRV_VERSION);
-
 	err = platform_driver_register(&xen_wdt_driver);
 	if (err)
 		return err;
@@ -351,7 +206,6 @@ static void __exit xen_wdt_cleanup_module(void)
 {
 	platform_device_unregister(platform_device);
 	platform_driver_unregister(&xen_wdt_driver);
-	pr_info("module unloaded\n");
 }
 
 module_init(xen_wdt_init_module);
@@ -359,5 +213,4 @@ module_exit(xen_wdt_cleanup_module);
 
 MODULE_AUTHOR("Jan Beulich <jbeulich@novell.com>");
 MODULE_DESCRIPTION("Xen WatchDog Timer Driver");
-MODULE_VERSION(DRV_VERSION);
 MODULE_LICENSE("GPL");