1 files changed, 159 insertions, 204 deletions

diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index 2ee7dac55a3..9d4874f0994 100644
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -2,6 +2,7 @@
  * Watchdog driver for IMX2 and later processors
  *
  *  Copyright (C) 2010 Wolfram Sang, Pengutronix e.K. <w.sang@pengutronix.de>
+ *  Copyright (C) 2014 Freescale Semiconductor, Inc.
  *
  * some parts adapted by similar drivers from Darius Augulis and Vladimir
  * Zapolskiy, additional improvements by Wim Van Sebroeck.
@@ -20,20 +21,17 @@
  * Halt on suspend:	Manual		Can be automatic
  */
 
+#include <linux/clk.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/watchdog.h>
-#include <linux/clk.h>
-#include <linux/fs.h>
-#include <linux/io.h>
-#include <linux/uaccess.h>
+#include <linux/regmap.h>
 #include <linux/timer.h>
-#include <linux/jiffies.h>
-#include <mach/hardware.h>
+#include <linux/watchdog.h>
 
 #define DRIVER_NAME "imx2-wdt"
 
@@ -41,32 +39,29 @@
 #define IMX2_WDT_WCR_WT		(0xFF << 8)	/* -> Watchdog Timeout Field */
 #define IMX2_WDT_WCR_WRE	(1 << 3)	/* -> WDOG Reset Enable */
 #define IMX2_WDT_WCR_WDE	(1 << 2)	/* -> Watchdog Enable */
+#define IMX2_WDT_WCR_WDZST	(1 << 0)	/* -> Watchdog timer Suspend */
 
 #define IMX2_WDT_WSR		0x02		/* Service Register */
 #define IMX2_WDT_SEQ1		0x5555		/* -> service sequence 1 */
 #define IMX2_WDT_SEQ2		0xAAAA		/* -> service sequence 2 */
 
+#define IMX2_WDT_WRSR		0x04		/* Reset Status Register */
+#define IMX2_WDT_WRSR_TOUT	(1 << 1)	/* -> Reset due to Timeout */
+
 #define IMX2_WDT_MAX_TIME	128
 #define IMX2_WDT_DEFAULT_TIME	60		/* in seconds */
 
 #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;
-	void __iomem *base;
-	unsigned timeout;
-	unsigned long status;
+	struct regmap *regmap;
 	struct timer_list timer;	/* Pings the watchdog when closed */
-} imx2_wdt;
-
-static struct miscdevice imx2_wdt_miscdev;
+	struct watchdog_device wdog;
+};
 
-static int nowayout = WATCHDOG_NOWAYOUT;
-module_param(nowayout, int, 0);
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
 				__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
 
@@ -81,10 +76,15 @@ 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)
 {
-	u16 val = __raw_readw(imx2_wdt.base + IMX2_WDT_WCR);
+	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
+	u32 val;
+
+	regmap_read(wdev->regmap, IMX2_WDT_WCR, &val);
 
+	/* Suspend timer in low power mode, write once-only */
+	val |= IMX2_WDT_WCR_WDZST;
 	/* Strip the old watchdog Time-Out value */
 	val &= ~IMX2_WDT_WCR_WT;
 	/* Generate reset if WDOG times out */
@@ -92,266 +92,221 @@ 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);
 
-	__raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR);
+	regmap_write(wdev->regmap, IMX2_WDT_WCR, val);
 
 	/* enable the watchdog */
 	val |= IMX2_WDT_WCR_WDE;
-	__raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR);
+	regmap_write(wdev->regmap, IMX2_WDT_WCR, val);
 }
 
-static inline void imx2_wdt_ping(void)
+static inline bool imx2_wdt_is_running(struct imx2_wdt_device *wdev)
 {
-	__raw_writew(IMX2_WDT_SEQ1, imx2_wdt.base + IMX2_WDT_WSR);
-	__raw_writew(IMX2_WDT_SEQ2, imx2_wdt.base + IMX2_WDT_WSR);
-}
+	u32 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);
+	regmap_read(wdev->regmap, IMX2_WDT_WCR, &val);
+
+	return val & IMX2_WDT_WCR_WDE;
 }
 
-static void imx2_wdt_start(void)
+static int imx2_wdt_ping(struct watchdog_device *wdog)
 {
-	if (!test_and_set_bit(IMX2_WDT_STATUS_STARTED, &imx2_wdt.status)) {
-		/* at our first start we enable clock and do initialisations */
-		clk_enable(imx2_wdt.clk);
-
-		imx2_wdt_setup();
-	} else	/* delete the timer that pings the watchdog after close */
-		del_timer_sync(&imx2_wdt.timer);
+	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
 
-	/* Watchdog is enabled - time to reload the timeout value */
-	imx2_wdt_ping();
+	regmap_write(wdev->regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ1);
+	regmap_write(wdev->regmap, IMX2_WDT_WSR, IMX2_WDT_SEQ2);
+	return 0;
 }
 
-static void imx2_wdt_stop(void)
+static void imx2_wdt_timer_ping(unsigned long arg)
 {
-	/* 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 watchdog_device *wdog = (struct watchdog_device *)arg;
+	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
+
+	/* ping it every wdog->timeout / 2 seconds to prevent reboot */
+	imx2_wdt_ping(wdog);
+	mod_timer(&wdev->timer, jiffies + wdog->timeout * HZ / 2);
 }
 
-static void imx2_wdt_set_timeout(int new_timeout)
+static int imx2_wdt_set_timeout(struct watchdog_device *wdog,
+				unsigned int new_timeout)
 {
-	u16 val = __raw_readw(imx2_wdt.base + IMX2_WDT_WCR);
+	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
 
-	/* set the new timeout value in the WSR */
-	val &= ~IMX2_WDT_WCR_WT;
-	val |= WDOG_SEC_TO_COUNT(new_timeout);
-	__raw_writew(val, imx2_wdt.base + IMX2_WDT_WCR);
+	regmap_update_bits(wdev->regmap, IMX2_WDT_WCR, IMX2_WDT_WCR_WT,
+			   WDOG_SEC_TO_COUNT(new_timeout));
+	return 0;
 }
 
-static int imx2_wdt_open(struct inode *inode, struct file *file)
+static int imx2_wdt_start(struct watchdog_device *wdog)
 {
-	if (test_and_set_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status))
-		return -EBUSY;
+	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
+
+	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);
 
-	imx2_wdt_start();
-	return nonseekable_open(inode, file);
+	return imx2_wdt_ping(wdog);
 }
 
-static int imx2_wdt_close(struct inode *inode, struct file *file)
+static int imx2_wdt_stop(struct watchdog_device *wdog)
 {
-	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();
-	}
-
-	clear_bit(IMX2_WDT_EXPECT_CLOSE, &imx2_wdt.status);
-	clear_bit(IMX2_WDT_STATUS_OPEN, &imx2_wdt.status);
+	/*
+	 * 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;
 }
 
-static long imx2_wdt_ioctl(struct file *file, unsigned int cmd,
-							unsigned long arg)
+static inline void imx2_wdt_ping_if_active(struct watchdog_device *wdog)
 {
-	void __user *argp = (void __user *)arg;
-	int __user *p = argp;
-	int new_value;
-
-	switch (cmd) {
-	case WDIOC_GETSUPPORT:
-		return copy_to_user(argp, &imx2_wdt_info,
-			sizeof(struct watchdog_info)) ? -EFAULT : 0;
-
-	case WDIOC_GETSTATUS:
-	case WDIOC_GETBOOTSTATUS:
-		return put_user(0, p);
-
-	case WDIOC_KEEPALIVE:
-		imx2_wdt_ping();
-		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;
-	}
-}
+	struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
 
-static ssize_t imx2_wdt_write(struct file *file, const char __user *data,
-						size_t len, loff_t *ppos)
-{
-	size_t i;
-	char c;
-
-	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,
+	.start = imx2_wdt_start,
+	.stop = imx2_wdt_stop,
+	.ping = imx2_wdt_ping,
+	.set_timeout = imx2_wdt_set_timeout,
 };
 
-static struct miscdevice imx2_wdt_miscdev = {
-	.minor = WATCHDOG_MINOR,
-	.name = "watchdog",
-	.fops = &imx2_wdt_fops,
+static struct regmap_config imx2_wdt_regmap_config = {
+	.reg_bits = 16,
+	.reg_stride = 2,
+	.val_bits = 16,
+	.max_register = 0x8,
 };
 
 static int __init imx2_wdt_probe(struct platform_device *pdev)
 {
-	int ret;
-	int res_size;
+	struct imx2_wdt_device *wdev;
+	struct watchdog_device *wdog;
 	struct resource *res;
+	void __iomem *base;
+	int ret;
+	u32 val;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-	if (!res) {
-		dev_err(&pdev->dev, "can't get device resources\n");
-		return -ENODEV;
-	}
-
-	res_size = resource_size(res);
-	if (!devm_request_mem_region(&pdev->dev, res->start, res_size,
-		res->name)) {
-		dev_err(&pdev->dev, "can't allocate %d bytes at %d address\n",
-			res_size, res->start);
+	wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL);
+	if (!wdev)
 		return -ENOMEM;
-	}
 
-	imx2_wdt.base = devm_ioremap_nocache(&pdev->dev, res->start, res_size);
-	if (!imx2_wdt.base) {
-		dev_err(&pdev->dev, "ioremap failed\n");
-		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);
+
+	wdev->regmap = devm_regmap_init_mmio_clk(&pdev->dev, NULL, base,
+						 &imx2_wdt_regmap_config);
+	if (IS_ERR(wdev->regmap)) {
+		dev_err(&pdev->dev, "regmap init failed\n");
+		return PTR_ERR(wdev->regmap);
 	}
 
-	imx2_wdt.clk = clk_get_sys("imx-wdt.0", 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);
+
+	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);
 
-fail:
-	imx2_wdt_miscdev.parent = NULL;
-	clk_put(imx2_wdt.clk);
-	return ret;
+	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");
-	} else
-		clk_put(imx2_wdt.clk);
-
-	imx2_wdt_miscdev.parent = NULL;
+	if (imx2_wdt_is_running(wdev)) {
+		del_timer_sync(&wdev->timer);
+		imx2_wdt_ping(wdog);
+		dev_crit(&pdev->dev, "Device removed: Expect reboot!\n");
+	}
 	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");
 	}
 }
 
+static const struct of_device_id imx2_wdt_dt_ids[] = {
+	{ .compatible = "fsl,imx21-wdt", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx2_wdt_dt_ids);
+
 static struct platform_driver imx2_wdt_driver = {
 	.remove		= __exit_p(imx2_wdt_remove),
 	.shutdown	= imx2_wdt_shutdown,
 	.driver		= {
 		.name	= DRIVER_NAME,
 		.owner	= THIS_MODULE,
+		.of_match_table = imx2_wdt_dt_ids,
 	},
 };
 
-static int __init imx2_wdt_init(void)
-{
-	return platform_driver_probe(&imx2_wdt_driver, imx2_wdt_probe);
-}
-module_init(imx2_wdt_init);
-
-static void __exit imx2_wdt_exit(void)
-{
-	platform_driver_unregister(&imx2_wdt_driver);
-}
-module_exit(imx2_wdt_exit);
+module_platform_driver_probe(imx2_wdt_driver, imx2_wdt_probe);
 
 MODULE_AUTHOR("Wolfram Sang");
 MODULE_DESCRIPTION("Watchdog driver for IMX2 and later");
 MODULE_LICENSE("GPL v2");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
 MODULE_ALIAS("platform:" DRIVER_NAME);