Commit 00411ee9 authored by Mark Brown's avatar Mark Brown Committed by Wim Van Sebroeck
Browse files

watchdog: Convert wm831x driver to watchdog core 



Fairly large code churn but not much doing with that and the overall
result is a definite win.

Signed-off-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: default avatarWim Van Sebroeck <wim@iguana.be>
parent 25dc46e3

drivers/watchdog/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -66,6 +66,7 @@ config SOFT_WATCHDOG 
config WM831X_WATCHDOG

	tristate "WM831x watchdog"

	depends on MFD_WM831X

	select WATCHDOG_CORE

	help

	  Support for the watchdog in the WM831x AudioPlus PMICs.  When

	  the watchdog triggers the system will be reset.

drivers/watchdog/wm831x_wdt.c

+105 −213
Original line number Diff line number Diff line
@@ -12,8 +12,7 @@ 
#include <linux/moduleparam.h>

#include <linux/types.h>

#include <linux/kernel.h>

#include <linux/fs.h>

#include <linux/miscdevice.h>

#include <linux/slab.h>

#include <linux/platform_device.h>

#include <linux/watchdog.h>

#include <linux/uaccess.h>
@@ -29,18 +28,18 @@ MODULE_PARM_DESC(nowayout, 
		 "Watchdog cannot be stopped once started (default="

		 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");



static unsigned long wm831x_wdt_users;

static struct miscdevice wm831x_wdt_miscdev;

static int wm831x_wdt_expect_close;

static DEFINE_MUTEX(wdt_mutex);

static struct wm831x *wm831x;

static unsigned int update_gpio;

static unsigned int update_state;

struct wm831x_wdt_drvdata {

	struct watchdog_device wdt;

	struct wm831x *wm831x;

	struct mutex lock;

	int update_gpio;

	int update_state;

};



/* We can't use the sub-second values here but they're included

 * for completeness.  */

static struct {

	int time;  /* Seconds */

	unsigned int time;  /* Seconds */

	u16 val;            /* WDOG_TO value */

} wm831x_wdt_cfgs[] = {

	{  1, 2 },
@@ -52,32 +51,13 @@ static struct { 
	{ 33, 7 },  /* Actually 32.768s so include both, others round down */

};



static int wm831x_wdt_set_timeout(struct wm831x *wm831x, u16 value)

{

	int ret;



	mutex_lock(&wdt_mutex);



	ret = wm831x_reg_unlock(wm831x);

	if (ret == 0) {

		ret = wm831x_set_bits(wm831x, WM831X_WATCHDOG,

				      WM831X_WDOG_TO_MASK, value);

		wm831x_reg_lock(wm831x);

	} else {

		dev_err(wm831x->dev, "Failed to unlock security key: %d\n",

			ret);

	}



	mutex_unlock(&wdt_mutex);



	return ret;

}



static int wm831x_wdt_start(struct wm831x *wm831x)

static int wm831x_wdt_start(struct watchdog_device *wdt_dev)

{

	struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);

	struct wm831x *wm831x = driver_data->wm831x;

	int ret;



	mutex_lock(&wdt_mutex);

	mutex_lock(&driver_data->lock);



	ret = wm831x_reg_unlock(wm831x);

	if (ret == 0) {
@@ -89,16 +69,18 @@ static int wm831x_wdt_start(struct wm831x *wm831x) 
			ret);

	}



	mutex_unlock(&wdt_mutex);

	mutex_unlock(&driver_data->lock);



	return ret;

}



static int wm831x_wdt_stop(struct wm831x *wm831x)

static int wm831x_wdt_stop(struct watchdog_device *wdt_dev)

{

	struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);

	struct wm831x *wm831x = driver_data->wm831x;

	int ret;



	mutex_lock(&wdt_mutex);

	mutex_lock(&driver_data->lock);



	ret = wm831x_reg_unlock(wm831x);

	if (ret == 0) {
@@ -110,26 +92,28 @@ static int wm831x_wdt_stop(struct wm831x *wm831x) 
			ret);

	}



	mutex_unlock(&wdt_mutex);

	mutex_unlock(&driver_data->lock);



	return ret;

}



static int wm831x_wdt_kick(struct wm831x *wm831x)

static int wm831x_wdt_ping(struct watchdog_device *wdt_dev)

{

	struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);

	struct wm831x *wm831x = driver_data->wm831x;

	int ret;

	u16 reg;



	mutex_lock(&wdt_mutex);

	mutex_lock(&driver_data->lock);



	if (update_gpio) {

		gpio_set_value_cansleep(update_gpio, update_state);

		update_state = !update_state;

	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);



	if (!(reg & WM831X_WDOG_RST_SRC)) {
@@ -150,182 +134,59 @@ static int wm831x_wdt_kick(struct wm831x *wm831x) 
	}



out:

	mutex_unlock(&wdt_mutex);

	mutex_unlock(&driver_data->lock);



	return ret;

}



static int wm831x_wdt_open(struct inode *inode, struct file *file)

{

	int ret;



	if (!wm831x)

		return -ENODEV;



	if (test_and_set_bit(0, &wm831x_wdt_users))

		return -EBUSY;



	ret = wm831x_wdt_start(wm831x);

	if (ret != 0)

		return ret;



	return nonseekable_open(inode, file);

}



static int wm831x_wdt_release(struct inode *inode, struct file *file)

{

	if (wm831x_wdt_expect_close)

		wm831x_wdt_stop(wm831x);

	else {

		dev_warn(wm831x->dev, "Watchdog device closed uncleanly\n");

		wm831x_wdt_kick(wm831x);

	}



	clear_bit(0, &wm831x_wdt_users);



	return 0;

}



static ssize_t wm831x_wdt_write(struct file *file,

				const char __user *data, size_t count,

				loff_t *ppos)

{

	size_t i;



	if (count) {

		wm831x_wdt_kick(wm831x);



		if (!nowayout) {

			/* In case it was set long ago */

			wm831x_wdt_expect_close = 0;



			/* scan to see whether or not we got the magic

			   character */

			for (i = 0; i != count; i++) {

				char c;

				if (get_user(c, data + i))

					return -EFAULT;

				if (c == 'V')

					wm831x_wdt_expect_close = 42;

			}

		}

	}

	return count;

}



static const struct watchdog_info ident = {

	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,

	.identity = "WM831x Watchdog",

};



static long wm831x_wdt_ioctl(struct file *file, unsigned int cmd,

			     unsigned long arg)

static int wm831x_wdt_set_timeout(struct watchdog_device *wdt_dev,

				  unsigned int timeout)

{

	int ret = -ENOTTY, time, i;

	void __user *argp = (void __user *)arg;

	int __user *p = argp;

	u16 reg;



	switch (cmd) {

	case WDIOC_GETSUPPORT:

		ret = copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;

		break;



	case WDIOC_GETSTATUS:

	case WDIOC_GETBOOTSTATUS:

		ret = put_user(0, p);

		break;



	case WDIOC_SETOPTIONS:

	{

		int options;



		if (get_user(options, p))

			return -EFAULT;



		ret = -EINVAL;



		/* Setting both simultaneously means at least one must fail */

		if (options == WDIOS_DISABLECARD)

			ret = wm831x_wdt_start(wm831x);



		if (options == WDIOS_ENABLECARD)

			ret = wm831x_wdt_stop(wm831x);

		break;

	}



	case WDIOC_KEEPALIVE:

		ret = wm831x_wdt_kick(wm831x);

		break;



	case WDIOC_SETTIMEOUT:

		ret = get_user(time, p);

		if (ret)

			break;



		if (time == 0) {

			if (nowayout)

				ret = -EINVAL;

			else

				wm831x_wdt_stop(wm831x);

			break;

		}

	struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);

	struct wm831x *wm831x = driver_data->wm831x;

	int ret, i;



	for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)

			if (wm831x_wdt_cfgs[i].time == time)

		if (wm831x_wdt_cfgs[i].time == timeout)

			break;

	if (i == ARRAY_SIZE(wm831x_wdt_cfgs))

		ret = -EINVAL;

		else

			ret = wm831x_wdt_set_timeout(wm831x,

						     wm831x_wdt_cfgs[i].val);

		break;



	case WDIOC_GETTIMEOUT:

		reg = wm831x_reg_read(wm831x, WM831X_WATCHDOG);

		reg &= WM831X_WDOG_TO_MASK;

		for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)

			if (wm831x_wdt_cfgs[i].val == reg)

				break;

		if (i == ARRAY_SIZE(wm831x_wdt_cfgs)) {

			dev_warn(wm831x->dev,

				 "Unknown watchdog configuration: %x\n", reg);

			ret = -EINVAL;

		} else

			ret = put_user(wm831x_wdt_cfgs[i].time, p);



	ret = wm831x_reg_unlock(wm831x);

	if (ret == 0) {

		ret = wm831x_set_bits(wm831x, WM831X_WATCHDOG,

				      WM831X_WDOG_TO_MASK,

				      wm831x_wdt_cfgs[i].val);

		wm831x_reg_lock(wm831x);

	} else {

		dev_err(wm831x->dev, "Failed to unlock security key: %d\n",

			ret);

	}



	return ret;

}



static const struct file_operations wm831x_wdt_fops = {

	.owner = THIS_MODULE,

	.llseek = no_llseek,

	.write = wm831x_wdt_write,

	.unlocked_ioctl = wm831x_wdt_ioctl,

	.open = wm831x_wdt_open,

	.release = wm831x_wdt_release,

static const struct watchdog_info wm831x_wdt_info = {

	.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,

	.identity = "WM831x Watchdog",

};



static struct miscdevice wm831x_wdt_miscdev = {

	.minor = WATCHDOG_MINOR,

	.name = "watchdog",

	.fops = &wm831x_wdt_fops,

static const struct watchdog_ops wm831x_wdt_ops = {

	.owner = THIS_MODULE,

	.start = wm831x_wdt_start,

	.stop = wm831x_wdt_stop,

	.ping = wm831x_wdt_ping,

	.set_timeout = wm831x_wdt_set_timeout,

};



static int __devinit wm831x_wdt_probe(struct platform_device *pdev)

{

	struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);

	struct wm831x_pdata *chip_pdata;

	struct wm831x_watchdog_pdata *pdata;

	int reg, ret;



	if (wm831x) {

		dev_err(&pdev->dev, "wm831x watchdog already registered\n");

		return -EBUSY;

	}



	wm831x = dev_get_drvdata(pdev->dev.parent);

	struct wm831x_wdt_drvdata *driver_data;

	struct watchdog_device *wm831x_wdt;

	int reg, ret, i;



	ret = wm831x_reg_read(wm831x, WM831X_WATCHDOG);

	if (ret < 0) {
@@ -338,6 +199,36 @@ static int __devinit wm831x_wdt_probe(struct platform_device *pdev) 
	if (reg & WM831X_WDOG_DEBUG)

		dev_warn(wm831x->dev, "Watchdog is paused\n");



	driver_data = kzalloc(sizeof(*driver_data), GFP_KERNEL);

	if (!driver_data) {

		dev_err(wm831x->dev, "Unable to alloacate watchdog device\n");

		ret = -ENOMEM;

		goto err;

	}



	mutex_init(&driver_data->lock);

	driver_data->wm831x = wm831x;



	wm831x_wdt = &driver_data->wdt;



	wm831x_wdt->info = &wm831x_wdt_info;

	wm831x_wdt->ops = &wm831x_wdt_ops;

	watchdog_set_drvdata(wm831x_wdt, driver_data);



	if (nowayout)

		wm831x_wdt->status |= WDOG_NO_WAY_OUT;



	reg = wm831x_reg_read(wm831x, WM831X_WATCHDOG);

	reg &= WM831X_WDOG_TO_MASK;

	for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)

		if (wm831x_wdt_cfgs[i].val == reg)

			break;

	if (i == ARRAY_SIZE(wm831x_wdt_cfgs))

		dev_warn(wm831x->dev,

			 "Unknown watchdog timeout: %x\n", reg);

	else

		wm831x_wdt->timeout = wm831x_wdt_cfgs[i].time;



	/* Apply any configuration */

	if (pdev->dev.parent->platform_data) {

		chip_pdata = pdev->dev.parent->platform_data;
@@ -361,7 +252,7 @@ static int __devinit wm831x_wdt_probe(struct platform_device *pdev) 
				dev_err(wm831x->dev,

					"Failed to request update GPIO: %d\n",

					ret);

				goto err;

				goto err_alloc;

			}



			ret = gpio_direction_output(pdata->update_gpio, 0);
@@ -372,7 +263,7 @@ static int __devinit wm831x_wdt_probe(struct platform_device *pdev) 
				goto err_gpio;

			}



			update_gpio = pdata->update_gpio;

			driver_data->update_gpio = pdata->update_gpio;



			/* Make sure the watchdog takes hardware updates */

			reg |= WM831X_WDOG_RST_SRC;
@@ -389,33 +280,34 @@ static int __devinit wm831x_wdt_probe(struct platform_device *pdev) 
		}

	}



	wm831x_wdt_miscdev.parent = &pdev->dev;



	ret = misc_register(&wm831x_wdt_miscdev);

	ret = watchdog_register_device(&driver_data->wdt);

	if (ret != 0) {

		dev_err(wm831x->dev, "Failed to register miscdev: %d\n", ret);

		dev_err(wm831x->dev, "watchdog_register_device() failed: %d\n",

			ret);

		goto err_gpio;

	}



	dev_set_drvdata(&pdev->dev, driver_data);



	return 0;



err_gpio:

	if (update_gpio) {

		gpio_free(update_gpio);

		update_gpio = 0;

	}

	if (driver_data->update_gpio)

		gpio_free(driver_data->update_gpio);

err_alloc:

	kfree(driver_data);

err:

	return ret;

}



static int __devexit wm831x_wdt_remove(struct platform_device *pdev)

{

	if (update_gpio) {

		gpio_free(update_gpio);

		update_gpio = 0;

	}

	struct wm831x_wdt_drvdata *driver_data = dev_get_drvdata(&pdev->dev);



	watchdog_unregister_device(&driver_data->wdt);



	misc_deregister(&wm831x_wdt_miscdev);

	if (driver_data->update_gpio)

		gpio_free(driver_data->update_gpio);



	return 0;

}