Commit e8fc721a authored by Andrew Lunn's avatar Andrew Lunn Committed by Anton Vorontsov

power/reset: Add a new driver to turn QNAP board power off

The QNAP NAS boxes have a microcontroller attached to the SoCs second
serial port. By sending it a simple command, it will turn the power for
the board off. This driver registers a function for pm_power_off to send
such a command.
Signed-off-by: default avatarAndrew Lunn <andrew@lunn.ch>
Signed-off-by: default avatarAnton Vorontsov <anton@enomsg.org>
parent 22f1229f
* QNAP Power Off
QNAP NAS devices have a microcontroller controlling the main power
supply. This microcontroller is connected to UART1 of the Kirkwood and
Orion5x SoCs. Sending the charactor 'A', at 19200 baud, tells the
microcontroller to turn the power off. This driver adds a handler to
pm_power_off which is called to turn the power off.
Required Properties:
- compatible: Should be "qnap,power-off"
- reg: Address and length of the register set for UART1
- clocks: tclk clock
......@@ -13,3 +13,12 @@ config POWER_RESET_GPIO
This driver supports turning off your board via a GPIO line.
If your board needs a GPIO high/low to power down, say Y and
create a binding in your devicetree.
config POWER_RESET_QNAP
bool "QNAP power-off driver"
depends on OF_GPIO && POWER_RESET && PLAT_ORION
help
This driver supports turning off QNAP NAS devices by sending
commands to the microcontroller which controls the main power.
Say Y if you have a QNAP NAS.
obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o
obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o
/*
* QNAP Turbo NAS Board power off
*
* Copyright (C) 2012 Andrew Lunn <andrew@lunn.ch>
*
* Based on the code from:
*
* Copyright (C) 2009 Martin Michlmayr <tbm@cyrius.com>
* Copyright (C) 2008 Byron Bradley <byron.bbradley@gmail.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/serial_reg.h>
#include <linux/kallsyms.h>
#include <linux/of.h>
#include <linux/io.h>
#include <linux/clk.h>
#define UART1_REG(x) (base + ((UART_##x) << 2))
static void __iomem *base;
static unsigned long tclk;
static void qnap_power_off(void)
{
/* 19200 baud divisor */
const unsigned divisor = ((tclk + (8 * 19200)) / (16 * 19200));
pr_err("%s: triggering power-off...\n", __func__);
/* hijack UART1 and reset into sane state (19200,8n1) */
writel(0x83, UART1_REG(LCR));
writel(divisor & 0xff, UART1_REG(DLL));
writel((divisor >> 8) & 0xff, UART1_REG(DLM));
writel(0x03, UART1_REG(LCR));
writel(0x00, UART1_REG(IER));
writel(0x00, UART1_REG(FCR));
writel(0x00, UART1_REG(MCR));
/* send the power-off command 'A' to PIC */
writel('A', UART1_REG(TX));
}
static int qnap_power_off_probe(struct platform_device *pdev)
{
struct resource *res;
struct clk *clk;
char symname[KSYM_NAME_LEN];
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(&pdev->dev, "Missing resource");
return -EINVAL;
}
base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
if (!base) {
dev_err(&pdev->dev, "Unable to map resource");
return -EINVAL;
}
/* We need to know tclk in order to calculate the UART divisor */
clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(clk)) {
dev_err(&pdev->dev, "Clk missing");
return PTR_ERR(clk);
}
tclk = clk_get_rate(clk);
/* Check that nothing else has already setup a handler */
if (pm_power_off) {
lookup_symbol_name((ulong)pm_power_off, symname);
dev_err(&pdev->dev,
"pm_power_off already claimed %p %s",
pm_power_off, symname);
return -EBUSY;
}
pm_power_off = qnap_power_off;
return 0;
}
static int qnap_power_off_remove(struct platform_device *pdev)
{
pm_power_off = NULL;
return 0;
}
static const struct of_device_id qnap_power_off_of_match_table[] = {
{ .compatible = "qnap,power-off", },
{}
};
MODULE_DEVICE_TABLE(of, qnap_power_off_of_match_table);
static struct platform_driver qnap_power_off_driver = {
.probe = qnap_power_off_probe,
.remove = qnap_power_off_remove,
.driver = {
.owner = THIS_MODULE,
.name = "qnap_power_off",
.of_match_table = of_match_ptr(qnap_power_off_of_match_table),
},
};
module_platform_driver(qnap_power_off_driver);
MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
MODULE_DESCRIPTION("QNAP Power off driver");
MODULE_LICENSE("GPLv2+");
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