usb: ohci-omap: Convert to use GPIO descriptors

The OMAP1 OHCI driver is using the legacy GPIO API to grab some
random GPIO lines. One is from the TPS65010 chip and used for
power, another one is for overcurrent and while the driver picks
this line it doesn't watch it at all.

Convert the driver and the OMAP1 OSK board file to pass these
two GPIOs as machine described GPIO descriptors.

I noticed the overcurrent GPIO line is not really used in the
code so dropped in a little comment for other developers.

Cc: Janusz Krzysztofik <jmkrzyszt@gmail.com>
Cc: Tony Lindgren <tony@atomide.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20200720135524.100374-2-linus.walleij@linaro.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arch/arm/mach-omap1/board-osk.c

@@ -26,6 +26,7 @@
  * 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 #include <linux/gpio.h>
+#include <linux/gpio/machine.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>
@@ -55,6 +56,9 @@
 
 #include "common.h"
 
+/* Name of the GPIO chip used by the OMAP for GPIOs 0..15 */
+#define OMAP_GPIO_LABEL		"gpio-0-15"
+
 /* At OMAP5912 OSK the Ethernet is directly connected to CS1 */
 #define OMAP_OSK_ETHR_START		0x04800300
 
@@ -240,7 +244,9 @@ static struct tps65010_board tps_board = {
 
 static struct i2c_board_info __initdata osk_i2c_board_info[] = {
 	{
+		/* This device will get the name "i2c-tps65010" */
 		I2C_BOARD_INFO("tps65010", 0x48),
+		.dev_name = "tps65010",
 		.platform_data	= &tps_board,
 
 	},
@@ -278,6 +284,16 @@ static void __init osk_init_cf(void)
 	irq_set_irq_type(gpio_to_irq(62), IRQ_TYPE_EDGE_FALLING);
 }
 
+static struct gpiod_lookup_table osk_usb_gpio_table = {
+	.dev_id = "ohci",
+	.table = {
+		/* Power GPIO on the I2C-attached TPS65010 */
+		GPIO_LOOKUP("i2c-tps65010", 1, "power", GPIO_ACTIVE_HIGH),
+		GPIO_LOOKUP(OMAP_GPIO_LABEL, 9, "overcurrent",
+			    GPIO_ACTIVE_HIGH),
+	},
+};
+
 static struct omap_usb_config osk_usb_config __initdata = {
 	/* has usb host connector (A) ... for development it can also
 	 * be used, with a NONSTANDARD gender-bending cable/dongle, as
@@ -581,6 +597,7 @@ static void __init osk_init(void)
 	l |= (3 << 1);
 	omap_writel(l, USB_TRANSCEIVER_CTRL);
 
+	gpiod_add_lookup_table(&osk_usb_gpio_table);
 	omap1_usb_init(&osk_usb_config);
 
 	/* irq for tps65010 chip */

drivers/usb/host/ohci-omap.c

@@ -18,7 +18,7 @@
 #include <linux/clk.h>
 #include <linux/dma-mapping.h>
 #include <linux/err.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
 #include <linux/io.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
@@ -53,25 +53,11 @@
 
 #define DRIVER_DESC "OHCI OMAP driver"
 
-#ifdef CONFIG_TPS65010
-#include <linux/mfd/tps65010.h>
-#else
-
-#define LOW	0
-#define HIGH	1
-
-#define GPIO1	1
-
-static inline int tps65010_set_gpio_out_value(unsigned gpio, unsigned value)
-{
-	return 0;
-}
-
-#endif
-
 struct ohci_omap_priv {
 	struct clk *usb_host_ck;
 	struct clk *usb_dc_ck;
+	struct gpio_desc *power;
+	struct gpio_desc *overcurrent;
 };
 
 static const char hcd_name[] = "ohci-omap";
@@ -97,22 +83,22 @@ static void omap_ohci_clock_power(struct ohci_omap_priv *priv, int on)
  * Board specific gang-switched transceiver power on/off.
  * NOTE:  OSK supplies power from DC, not battery.
  */
-static int omap_ohci_transceiver_power(int on)
+static int omap_ohci_transceiver_power(struct ohci_omap_priv *priv, int on)
 {
 	if (on) {
 		if (machine_is_omap_innovator() && cpu_is_omap1510())
 			__raw_writeb(__raw_readb(INNOVATOR_FPGA_CAM_USB_CONTROL)
 				| ((1 << 5/*usb1*/) | (1 << 3/*usb2*/)),
 			       INNOVATOR_FPGA_CAM_USB_CONTROL);
-		else if (machine_is_omap_osk())
-			tps65010_set_gpio_out_value(GPIO1, LOW);
+		else if (priv->power)
+			gpiod_set_value(priv->power, 0);
 	} else {
 		if (machine_is_omap_innovator() && cpu_is_omap1510())
 			__raw_writeb(__raw_readb(INNOVATOR_FPGA_CAM_USB_CONTROL)
 				& ~((1 << 5/*usb1*/) | (1 << 3/*usb2*/)),
 			       INNOVATOR_FPGA_CAM_USB_CONTROL);
-		else if (machine_is_omap_osk())
-			tps65010_set_gpio_out_value(GPIO1, HIGH);
+		else if (priv->power)
+			gpiod_set_value(priv->power, 1);
 	}
 
 	return 0;
@@ -272,8 +258,6 @@ static int ohci_omap_reset(struct usb_hcd *hcd)
 
 			/* gpio9 for overcurrent detction */
 			omap_cfg_reg(W8_1610_GPIO9);
-			gpio_request(9, "OHCI overcurrent");
-			gpio_direction_input(9);
 
 			/* for paranoia's sake:  disable USB.PUEN */
 			omap_cfg_reg(W4_USB_HIGHZ);
@@ -287,7 +271,7 @@ static int ohci_omap_reset(struct usb_hcd *hcd)
 	}
 
 	/* FIXME hub_wq hub requests should manage power switching */
-	omap_ohci_transceiver_power(1);
+	omap_ohci_transceiver_power(priv, 1);
 
 	/* board init will have already handled HMC and mux setup.
 	 * any external transceiver should already be initialized
@@ -334,6 +318,29 @@ static int ohci_hcd_omap_probe(struct platform_device *pdev)
 	hcd->rsrc_len = pdev->resource[0].end - pdev->resource[0].start + 1;
 	priv = hcd_to_ohci_omap_priv(hcd);
 
+	/* Obtain two optional GPIO lines */
+	priv->power = devm_gpiod_get_optional(&pdev->dev, "power", GPIOD_ASIS);
+	if (IS_ERR(priv->power)) {
+		retval = PTR_ERR(priv->power);
+		goto err_put_hcd;
+	}
+	if (priv->power)
+		gpiod_set_consumer_name(priv->power, "OHCI power");
+
+	/*
+	 * This "overcurrent" GPIO line isn't really used in the code,
+	 * but has a designated hardware function.
+	 * TODO: implement proper overcurrent handling.
+	 */
+	priv->overcurrent = devm_gpiod_get_optional(&pdev->dev, "overcurrent",
+						    GPIOD_IN);
+	if (IS_ERR(priv->overcurrent)) {
+		retval = PTR_ERR(priv->overcurrent);
+		goto err_put_hcd;
+	}
+	if (priv->overcurrent)
+		gpiod_set_consumer_name(priv->overcurrent, "OHCI overcurrent");
+
 	priv->usb_host_ck = clk_get(&pdev->dev, "usb_hhc_ck");
 	if (IS_ERR(priv->usb_host_ck)) {
 		retval = PTR_ERR(priv->usb_host_ck);
@@ -411,8 +418,6 @@ static int ohci_hcd_omap_remove(struct platform_device *pdev)
 		(void) otg_set_host(hcd->usb_phy->otg, 0);
 		usb_put_phy(hcd->usb_phy);
 	}
-	if (machine_is_omap_osk())
-		gpio_free(9);
 	iounmap(hcd->regs);
 	release_mem_region(hcd->rsrc_start, hcd->rsrc_len);
 	clk_put(priv->usb_dc_ck);