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path: root/drivers/watchdog/imx2_wdt.c
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Diffstat (limited to 'drivers/watchdog/imx2_wdt.c')
-rw-r--r--drivers/watchdog/imx2_wdt.c320
1 files changed, 143 insertions, 177 deletions
diff --git a/drivers/watchdog/imx2_wdt.c b/drivers/watchdog/imx2_wdt.c
index dd51d9539b3..9d4874f0994 100644
--- a/drivers/watchdog/imx2_wdt.c
+++ b/drivers/watchdog/imx2_wdt.c
@@ -21,19 +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 <linux/watchdog.h>
#define DRIVER_NAME "imx2-wdt"
@@ -55,19 +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;
- 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 bool nowayout = WATCHDOG_NOWAYOUT;
module_param(nowayout, bool, 0);
@@ -85,9 +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)
{
- 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;
@@ -98,227 +92,199 @@ 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_prepare_enable(imx2_wdt.clk);
+ struct imx2_wdt_device *wdev = watchdog_get_drvdata(wdog);
- imx2_wdt_setup();
- } else /* delete the timer that pings the watchdog after close */
- del_timer_sync(&imx2_wdt.timer);
-
- /* 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;
- u16 val;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- return copy_to_user(argp, &imx2_wdt_info,
- sizeof(struct watchdog_info)) ? -EFAULT : 0;
-
- case WDIOC_GETSTATUS:
- return put_user(0, p);
-
- case WDIOC_GETBOOTSTATUS:
- val = __raw_readw(imx2_wdt.base + IMX2_WDT_WRSR);
- new_value = val & IMX2_WDT_WRSR_TOUT ? WDIOF_CARDRESET : 0;
- return put_user(new_value, 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;
+ 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);
- imx2_wdt.base = devm_ioremap_resource(&pdev->dev, res);
- if (IS_ERR(imx2_wdt.base))
- return PTR_ERR(imx2_wdt.base);
+ 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 = 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);
+
+ 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;
- 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");
+ 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");
}
}