Commit faad5de0 authored by Anatolij Gustschin's avatar Anatolij Gustschin Committed by Wim Van Sebroeck
Browse files

watchdog: imx2_wdt: convert to watchdog core api 



Convert the imx2_wdt driver to the new watchdog core api.

Signed-off-by: default avatarAnatolij Gustschin <agust@denx.de>
Reviewed-by: default avatarGuenter Roeck <linux@roeck-us.net>
Cc: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: default avatarWim Van Sebroeck <wim@iguana.be>
parent a7977003

drivers/watchdog/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -379,6 +379,7 @@ config IMX2_WDT 
	tristate "IMX2+ Watchdog"

	depends on ARCH_MXC

	select REGMAP_MMIO

	select WATCHDOG_CORE

	help

	  This is the driver for the hardware watchdog

	  on the Freescale IMX2 and later processors.

drivers/watchdog/imx2_wdt.c

+122 −170
Original line number Diff line number Diff line
@@ -22,18 +22,15 @@ 
 */



#include <linux/clk.h>

#include <linux/fs.h>

#include <linux/init.h>

#include <linux/io.h>

#include <linux/jiffies.h>

#include <linux/kernel.h>

#include <linux/miscdevice.h>

#include <linux/module.h>

#include <linux/moduleparam.h>

#include <linux/platform_device.h>

#include <linux/regmap.h>

#include <linux/timer.h>

#include <linux/uaccess.h>

#include <linux/watchdog.h>



#define DRIVER_NAME "imx2-wdt"
@@ -56,19 +53,12 @@ 


#define WDOG_SEC_TO_COUNT(s)	((s * 2 - 1) << 8)



#define IMX2_WDT_STATUS_OPEN	0

#define IMX2_WDT_STATUS_STARTED	1

#define IMX2_WDT_EXPECT_CLOSE	2



static struct {

struct imx2_wdt_device {

	struct clk *clk;

	struct regmap *regmap;

	unsigned timeout;

	unsigned long status;

	struct timer_list timer;	/* Pings the watchdog when closed */

} imx2_wdt;



static struct miscdevice imx2_wdt_miscdev;

	struct watchdog_device wdog;

};



static bool nowayout = WATCHDOG_NOWAYOUT;

module_param(nowayout, bool, 0);
@@ -86,11 +76,12 @@ static const struct watchdog_info imx2_wdt_info = { 
	.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE,

};



static inline void imx2_wdt_setup(void)

static inline void imx2_wdt_setup(struct watchdog_device *wdog)

{

	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);

	u32 val;



	regmap_read(imx2_wdt.regmap, IMX2_WDT_WCR, &val);

	regmap_read(wdev->regmap, IMX2_WDT_WCR, &val);



	/* Suspend timer in low power mode, write once-only */

	val |= IMX2_WDT_WCR_WDZST;
@@ -101,157 +92,93 @@ static inline void imx2_wdt_setup(void) 
	/* Keep Watchdog Disabled */

	val &= ~IMX2_WDT_WCR_WDE;

	/* Set the watchdog's Time-Out value */

	val |= WDOG_SEC_TO_COUNT(imx2_wdt.timeout);

	val |= WDOG_SEC_TO_COUNT(wdog->timeout);



	regmap_write(imx2_wdt.regmap, IMX2_WDT_WCR, val);

	regmap_write(wdev->regmap, IMX2_WDT_WCR, val);



	/* enable the watchdog */

	val |= IMX2_WDT_WCR_WDE;

	regmap_write(imx2_wdt.regmap, IMX2_WDT_WCR, val);

}



static inline void imx2_wdt_ping(void)

{

	regmap_write(imx2_wdt.regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ1);

	regmap_write(imx2_wdt.regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ2);

	regmap_write(wdev->regmap, IMX2_WDT_WCR, val);

}



static void imx2_wdt_timer_ping(unsigned long arg)

{

	/* ping it every imx2_wdt.timeout / 2 seconds to prevent reboot */

	imx2_wdt_ping();

	mod_timer(&imx2_wdt.timer, jiffies + imx2_wdt.timeout * HZ / 2);

}



static void imx2_wdt_start(void)

static inline bool imx2_wdt_is_running(struct imx2_wdt_device *wdev)

{

	if (!test_and_set_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) {

		/* at our first start we enable clock and do initialisations */

		clk_prepare_enable(imx2_wdt.clk);

	u32 val;



		imx2_wdt_setup();

	} else	/* delete the timer that pings the watchdog after close */

		del_timer_sync(&imx2_wdt.timer);

	regmap_read(wdev->regmap, IMX2_WDT_WCR, &val);



	/* Watchdog is enabled - time to reload the timeout value */

	imx2_wdt_ping();

	return val & IMX2_WDT_WCR_WDE;

}



static void imx2_wdt_stop(void)

static int imx2_wdt_ping(struct watchdog_device *wdog)

{

	/* we don't need a clk_disable, it cannot be disabled once started.

	 * We use a timer to ping the watchdog while /dev/watchdog is closed */

	imx2_wdt_timer_ping(0);

}

	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);



static void imx2_wdt_set_timeout(int new_timeout)

{

	regmap_update_bits(imx2_wdt.regmap, IMX2_WDT_WCR, IMX2_WDT_WCR_WT,

			   WDOG_SEC_TO_COUNT(new_timeout));

	regmap_write(wdev->regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ1);

	regmap_write(wdev->regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ2);

	return 0;

}



static int imx2_wdt_open(struct inode *inode, struct file *file)

static void imx2_wdt_timer_ping(unsigned long arg)

{

	if (test_and_set_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status))

		return -EBUSY;

	struct watchdog_device *wdog = (struct watchdog_device *)arg;

	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);



	imx2_wdt_start();

	return nonseekable_open(inode, file);

	/* ping it every wdog->timeout / 2 seconds to prevent reboot */

	imx2_wdt_ping(wdog);

	mod_timer(&wdev->timer, jiffies + wdog->timeout * HZ / 2);

}



static int imx2_wdt_close(struct inode *inode, struct file *file)

static int imx2_wdt_set_timeout(struct watchdog_device *wdog,

				unsigned int new_timeout)

{

	if (test_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status) && !nowayout)

		imx2_wdt_stop();

	else {

		dev_crit(imx2_wdt_miscdev.parent,

			"Unexpected close: Expect reboot!\n");

		imx2_wdt_ping();

	}

	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);



	clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status);

	clear_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status);

	regmap_update_bits(wdev->regmap, IMX2_WDT_WCR, IMX2_WDT_WCR_WT,

			   WDOG_SEC_TO_COUNT(new_timeout));

	return 0;

}



static long imx2_wdt_ioctl(struct file *file, unsigned int cmd,

							unsigned long arg)

static int imx2_wdt_start(struct watchdog_device *wdog)

{

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

	int __user *p = argp;

	int new_value;

	u32 val;



	switch (cmd) {

	case WDIOC_GETSUPPORT:

		return copy_to_user(argp, &imx2_wdt_info,

			sizeof(struct watchdog_info)) ? -EFAULT : 0;

	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);



	case WDIOC_GETSTATUS:

		return put_user(0, p);

	if (imx2_wdt_is_running(wdev)) {

		/* delete the timer that pings the watchdog after close */

		del_timer_sync(&wdev->timer);

		imx2_wdt_set_timeout(wdog, wdog->timeout);

	} else

		imx2_wdt_setup(wdog);



	case WDIOC_GETBOOTSTATUS:

		regmap_read(imx2_wdt.regmap, IMX2_WDT_WRSR, &val);

		new_value = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0;

		return put_user(new_value, p);

	return imx2_wdt_ping(wdog);

}



	case WDIOC_KEEPALIVE:

		imx2_wdt_ping();

static int imx2_wdt_stop(struct watchdog_device *wdog)

{

	/*

	 * We don't need a clk_disable, it cannot be disabled once started.

	 * We use a timer to ping the watchdog while /dev/watchdog is closed

	 */

	imx2_wdt_timer_ping((unsigned long)wdog);

	return 0;



	case WDIOC_SETTIMEOUT:

		if (get_user(new_value, p))

			return -EFAULT;

		if ((new_value < 1) || (new_value > IMX2_WDT_MAX_TIME))

			return -EINVAL;

		imx2_wdt_set_timeout(new_value);

		imx2_wdt.timeout = new_value;

		imx2_wdt_ping();



		/* Fallthrough to return current value */

	case WDIOC_GETTIMEOUT:

		return put_user(imx2_wdt.timeout, p);



	default:

		return -ENOTTY;

	}

}



static ssize_t imx2_wdt_write(struct file *file, const char __user *data,

						size_t len, loff_t *ppos)

static inline void imx2_wdt_ping_if_active(struct watchdog_device *wdog)

{

	size_t i;

	char c;

	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);



	if (len == 0)	/* Can we see this even ? */

		return 0;



	clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status);

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

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

		if (get_user(c, data + i))

			return -EFAULT;

		if (c == 'V')

			set_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status);

	if (imx2_wdt_is_running(wdev)) {

		imx2_wdt_set_timeout(wdog, wdog->timeout);

		imx2_wdt_timer_ping((unsigned long)wdog);

	}



	imx2_wdt_ping();

	return len;

}



static const struct file_operations imx2_wdt_fops = {

static struct watchdog_ops imx2_wdt_ops = {

	.owner = THIS_MODULE,

	.llseek = no_llseek,

	.unlocked_ioctl = imx2_wdt_ioctl,

	.open = imx2_wdt_open,

	.release = imx2_wdt_close,

	.write = imx2_wdt_write,

};



static struct miscdevice imx2_wdt_miscdev = {

	.minor = WATCHDOG_MINOR,

	.name = "watchdog",

	.fops = &imx2_wdt_fops,

	.start = imx2_wdt_start,

	.stop = imx2_wdt_stop,

	.ping = imx2_wdt_ping,

	.set_timeout = imx2_wdt_set_timeout,

};



static struct regmap_config imx2_wdt_regmap_config = {
@@ -263,76 +190,101 @@ static struct regmap_config imx2_wdt_regmap_config = { 


static int __init imx2_wdt_probe(struct platform_device *pdev)

{

	struct imx2_wdt_device *wdev;

	struct watchdog_device *wdog;

	struct resource *res;

	void __iomem *base;

	int ret;

	u32 val;



	wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL);

	if (!wdev)

		return -ENOMEM;



	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	base = devm_ioremap_resource(&pdev->dev, res);

	if (IS_ERR(base))

		return PTR_ERR(base);



	imx2_wdt.regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,

	wdev->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,

						 &imx2_wdt_regmap_config);

	if (IS_ERR(imx2_wdt.regmap)) {

	if (IS_ERR(wdev->regmap)) {

		dev_err(&pdev->dev, "regmap init failed\n");

		return PTR_ERR(imx2_wdt.regmap);

		return PTR_ERR(wdev->regmap);

	}



	imx2_wdt.clk = devm_clk_get(&pdev->dev, NULL);

	if (IS_ERR(imx2_wdt.clk)) {

	wdev->clk = devm_clk_get(&pdev->dev, NULL);

	if (IS_ERR(wdev->clk)) {

		dev_err(&pdev->dev, "can't get Watchdog clock\n");

		return PTR_ERR(imx2_wdt.clk);

		return PTR_ERR(wdev->clk);

	}



	imx2_wdt.timeout = clamp_t(unsigned, timeout, 1, IMX2_WDT_MAX_TIME);

	if (imx2_wdt.timeout != timeout)

		dev_warn(&pdev->dev, "Initial timeout out of range! "

			"Clamped from %u to %u\n", timeout, imx2_wdt.timeout);

	wdog			= &wdev->wdog;

	wdog->info		= &imx2_wdt_info;

	wdog->ops		= &imx2_wdt_ops;

	wdog->min_timeout	= 1;

	wdog->max_timeout	= IMX2_WDT_MAX_TIME;



	setup_timer(&imx2_wdt.timer, imx2_wdt_timer_ping, 0);

	clk_prepare_enable(wdev->clk);



	imx2_wdt_miscdev.parent = &pdev->dev;

	ret = misc_register(&imx2_wdt_miscdev);

	if (ret)

		goto fail;

	regmap_read(wdev->regmap, IMX2_WDT_WRSR, &val);

	wdog->bootstatus = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0;



	dev_info(&pdev->dev,

		"IMX2+ Watchdog Timer enabled. timeout=%ds (nowayout=%d)\n",

						imx2_wdt.timeout, nowayout);

	return 0;

	wdog->timeout = clamp_t(unsigned, timeout, 1, IMX2_WDT_MAX_TIME);

	if (wdog->timeout != timeout)

		dev_warn(&pdev->dev, "Initial timeout out of range! Clamped from %u to %u\n",

			 timeout, wdog->timeout);



fail:

	imx2_wdt_miscdev.parent = NULL;

	platform_set_drvdata(pdev, wdog);

	watchdog_set_drvdata(wdog, wdev);

	watchdog_set_nowayout(wdog, nowayout);

	watchdog_init_timeout(wdog, timeout, &pdev->dev);



	setup_timer(&wdev->timer, imx2_wdt_timer_ping, (unsigned long)wdog);



	imx2_wdt_ping_if_active(wdog);



	ret = watchdog_register_device(wdog);

	if (ret) {

		dev_err(&pdev->dev, "cannot register watchdog device\n");

		return ret;

	}



	dev_info(&pdev->dev, "timeout %d sec (nowayout=%d)\n",

		 wdog->timeout, nowayout);



	return 0;

}



static int __exit imx2_wdt_remove(struct platform_device *pdev)

{

	misc_deregister(&imx2_wdt_miscdev);

	struct watchdog_device *wdog = platform_get_drvdata(pdev);

	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);



	if (test_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) {

		del_timer_sync(&imx2_wdt.timer);

	watchdog_unregister_device(wdog);



		dev_crit(imx2_wdt_miscdev.parent,

			"Device removed: Expect reboot!\n");

	if (imx2_wdt_is_running(wdev)) {

		del_timer_sync(&wdev->timer);

		imx2_wdt_ping(wdog);

		dev_crit(&pdev->dev, "Device removed: Expect reboot!\n");

	}



	imx2_wdt_miscdev.parent = NULL;

	return 0;

}



static void imx2_wdt_shutdown(struct platform_device *pdev)

{

	if (test_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) {

		/* we are running, we need to delete the timer but will give

		 * max timeout before reboot will take place */

		del_timer_sync(&imx2_wdt.timer);

		imx2_wdt_set_timeout(IMX2_WDT_MAX_TIME);

		imx2_wdt_ping();



		dev_crit(imx2_wdt_miscdev.parent,

			"Device shutdown: Expect reboot!\n");

	struct watchdog_device *wdog = platform_get_drvdata(pdev);

	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);



	if (imx2_wdt_is_running(wdev)) {

		/*

		 * We are running, we need to delete the timer but will

		 * give max timeout before reboot will take place

		 */

		del_timer_sync(&wdev->timer);

		imx2_wdt_set_timeout(wdog, IMX2_WDT_MAX_TIME);

		imx2_wdt_ping(wdog);

		dev_crit(&pdev->dev, "Device shutdown: Expect reboot!\n");

	}

}