watchdog: wm831x_wdt: Remove GPIO handling

An attempt to convert the driver to using GPIO descriptors
(see Link tag) was discouraged in favor of deleting the
handling of the update GPIO altogehter since there are
no in-tree users.

This patch deletes the GPIO handling instead.

Cc: Richard Fitzgerald <[e-mail]>
Cc: Charles Keepax <[e-mail]>
Cc: Mark Brown <[e-mail]>
Link: https://lore.kernel.org/linux-watchdog/[e-mail]/
Signed-off-by: Linus Walleij <[e-mail]>
Reviewed-by: Guenter Roeck <[e-mail]>
Acked-by: Charles Keepax <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Guenter Roeck <[e-mail]>
Signed-off-by: Wim Van Sebroeck <[e-mail]>

drivers/watchdog/wm831x_wdt.c

···
 #include <linux/platform_device.h>
 #include <linux/watchdog.h>
 #include <linux/uaccess.h>
-#include <linux/gpio.h>
 
 #include <linux/mfd/wm831x/core.h>
 #include <linux/mfd/wm831x/pdata.h>
···
 	struct watchdog_device wdt;
 	struct wm831x *wm831x;
 	struct mutex lock;
-	int update_gpio;
 	int update_state;
 };
 
···
 	u16 reg;
 
 	mutex_lock(&driver_data->lock);
-
-	if (driver_data->update_gpio) {
-		gpio_set_value_cansleep(driver_data->update_gpio,
-					driver_data->update_state);
-		driver_data->update_state = !driver_data->update_state;
-		ret = 0;
-		goto out;
-	}
 
 	reg = wm831x_reg_read(wm831x, WM831X_WATCHDOG);
 
···
 		reg |= pdata->primary << WM831X_WDOG_PRIMACT_SHIFT;
 		reg |= pdata->secondary << WM831X_WDOG_SECACT_SHIFT;
 		reg |= pdata->software << WM831X_WDOG_RST_SRC_SHIFT;
-
-		if (pdata->update_gpio) {
-			ret = devm_gpio_request_one(dev, pdata->update_gpio,
-						    GPIOF_OUT_INIT_LOW,
-						    "Watchdog update");
-			if (ret < 0) {
-				dev_err(wm831x->dev,
-					"Failed to request update GPIO: %d\n",
-					ret);
-				return ret;
-			}
-
-			driver_data->update_gpio = pdata->update_gpio;
-
-			/* Make sure the watchdog takes hardware updates */
-			reg |= WM831X_WDOG_RST_SRC;
-		}
 
 		ret = wm831x_reg_unlock(wm831x);
 		if (ret == 0) {

include/linux/mfd/wm831x/pdata.h

···
 
 struct wm831x_watchdog_pdata {
 	enum wm831x_watchdog_action primary, secondary;
-	int update_gpio;
 	unsigned int software:1;
 };