[RFC 2/6] watchdog: s3c2410: convert to use the watchdog framework
From: Wolfram Sang
Date: Wed Jul 13 2011 - 16:25:53 EST
Make this driver a user of the watchdog framework and remove now
centrally handled parts. Tested on a mini2440.
Signed-off-by: Wolfram Sang <w.sang@xxxxxxxxxxxxxx>
---
drivers/watchdog/Kconfig | 1 +
drivers/watchdog/s3c2410_wdt.c | 176 +++++++++-------------------------------
2 files changed, 38 insertions(+), 139 deletions(-)
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index edb0f1b..4f1379c 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -173,6 +173,7 @@ config HAVE_S3C2410_WATCHDOG
config S3C2410_WATCHDOG
tristate "S3C2410 Watchdog"
depends on ARCH_S3C2410 || HAVE_S3C2410_WATCHDOG
+ select WATCHDOG_CORE
help
Watchdog timer block in the Samsung SoCs. This will reboot
the system when the timer expires with the watchdog enabled.
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 30da88f..5de7e4f 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -27,9 +27,8 @@
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/timer.h>
-#include <linux/miscdevice.h>
+#include <linux/miscdevice.h> /* for MODULE_ALIAS_MISCDEV */
#include <linux/watchdog.h>
-#include <linux/fs.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
@@ -38,6 +37,7 @@
#include <linux/io.h>
#include <linux/cpufreq.h>
#include <linux/slab.h>
+#include <linux/err.h>
#include <mach/map.h>
@@ -74,14 +74,12 @@ MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, "
"0 to reboot (default 0)");
MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)");
-static unsigned long open_lock;
static struct device *wdt_dev; /* platform device attached to */
static struct resource *wdt_mem;
static struct resource *wdt_irq;
static struct clk *wdt_clock;
static void __iomem *wdt_base;
static unsigned int wdt_count;
-static char expect_close;
static DEFINE_SPINLOCK(wdt_lock);
/* watchdog control routines */
@@ -93,11 +91,13 @@ static DEFINE_SPINLOCK(wdt_lock);
/* functions */
-static void s3c2410wdt_keepalive(void)
+static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
{
spin_lock(&wdt_lock);
writel(wdt_count, wdt_base + S3C2410_WTCNT);
spin_unlock(&wdt_lock);
+
+ return 0;
}
static void __s3c2410wdt_stop(void)
@@ -109,14 +109,16 @@ static void __s3c2410wdt_stop(void)
writel(wtcon, wdt_base + S3C2410_WTCON);
}
-static void s3c2410wdt_stop(void)
+static int s3c2410wdt_stop(struct watchdog_device *wdd)
{
spin_lock(&wdt_lock);
__s3c2410wdt_stop();
spin_unlock(&wdt_lock);
+
+ return 0;
}
-static void s3c2410wdt_start(void)
+static int s3c2410wdt_start(struct watchdog_device *wdd)
{
unsigned long wtcon;
@@ -142,6 +144,8 @@ static void s3c2410wdt_start(void)
writel(wdt_count, wdt_base + S3C2410_WTCNT);
writel(wtcon, wdt_base + S3C2410_WTCON);
spin_unlock(&wdt_lock);
+
+ return 0;
}
static inline int s3c2410wdt_is_running(void)
@@ -149,7 +153,7 @@ static inline int s3c2410wdt_is_running(void)
return readl(wdt_base + S3C2410_WTCON) & S3C2410_WTCON_ENABLE;
}
-static int s3c2410wdt_set_heartbeat(int timeout)
+static int s3c2410wdt_set_heartbeat(struct watchdog_device *wdd, unsigned timeout)
{
unsigned long freq = clk_get_rate(wdt_clock);
unsigned int count;
@@ -182,8 +186,6 @@ static int s3c2410wdt_set_heartbeat(int timeout)
}
}
- tmr_margin = timeout;
-
DBG("%s: timeout=%d, divisor=%d, count=%d (%08x)\n",
__func__, timeout, divisor, count, count/divisor);
@@ -201,70 +203,6 @@ static int s3c2410wdt_set_heartbeat(int timeout)
return 0;
}
-/*
- * /dev/watchdog handling
- */
-
-static int s3c2410wdt_open(struct inode *inode, struct file *file)
-{
- if (test_and_set_bit(0, &open_lock))
- return -EBUSY;
-
- if (nowayout)
- __module_get(THIS_MODULE);
-
- expect_close = 0;
-
- /* start the timer */
- s3c2410wdt_start();
- return nonseekable_open(inode, file);
-}
-
-static int s3c2410wdt_release(struct inode *inode, struct file *file)
-{
- /*
- * Shut off the timer.
- * Lock it in if it's a module and we set nowayout
- */
-
- if (expect_close == 42)
- s3c2410wdt_stop();
- else {
- dev_err(wdt_dev, "Unexpected close, not stopping watchdog\n");
- s3c2410wdt_keepalive();
- }
- expect_close = 0;
- clear_bit(0, &open_lock);
- return 0;
-}
-
-static ssize_t s3c2410wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
-{
- /*
- * Refresh the timer.
- */
- if (len) {
- if (!nowayout) {
- size_t i;
-
- /* In case it was set long ago */
- expect_close = 0;
-
- for (i = 0; i != len; i++) {
- char c;
-
- if (get_user(c, data + i))
- return -EFAULT;
- if (c == 'V')
- expect_close = 42;
- }
- }
- s3c2410wdt_keepalive();
- }
- return len;
-}
-
#define OPTIONS (WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE)
static const struct watchdog_info s3c2410_wdt_ident = {
@@ -273,53 +211,17 @@ static const struct watchdog_info s3c2410_wdt_ident = {
.identity = "S3C2410 Watchdog",
};
-
-static long s3c2410wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- void __user *argp = (void __user *)arg;
- int __user *p = argp;
- int new_margin;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- return copy_to_user(argp, &s3c2410_wdt_ident,
- sizeof(s3c2410_wdt_ident)) ? -EFAULT : 0;
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- return put_user(0, p);
- case WDIOC_KEEPALIVE:
- s3c2410wdt_keepalive();
- return 0;
- case WDIOC_SETTIMEOUT:
- if (get_user(new_margin, p))
- return -EFAULT;
- if (s3c2410wdt_set_heartbeat(new_margin))
- return -EINVAL;
- s3c2410wdt_keepalive();
- return put_user(tmr_margin, p);
- case WDIOC_GETTIMEOUT:
- return put_user(tmr_margin, p);
- default:
- return -ENOTTY;
- }
-}
-
-/* kernel interface */
-
-static const struct file_operations s3c2410wdt_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = s3c2410wdt_write,
- .unlocked_ioctl = s3c2410wdt_ioctl,
- .open = s3c2410wdt_open,
- .release = s3c2410wdt_release,
+static struct watchdog_ops s3c2410wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = s3c2410wdt_start,
+ .stop = s3c2410wdt_stop,
+ .ping = s3c2410wdt_keepalive,
+ .set_timeout = s3c2410wdt_set_heartbeat,
};
-static struct miscdevice s3c2410wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &s3c2410wdt_fops,
+static struct watchdog_device s3c2410_wdd = {
+ .info = &s3c2410_wdt_ident,
+ .ops = &s3c2410wdt_ops,
};
/* interrupt handler code */
@@ -328,7 +230,7 @@ static irqreturn_t s3c2410wdt_irq(int irqno, void *param)
{
dev_info(wdt_dev, "watchdog timer expired (irq)\n");
- s3c2410wdt_keepalive();
+ s3c2410wdt_keepalive(&s3c2410_wdd);
return IRQ_HANDLED;
}
@@ -349,14 +251,14 @@ static int s3c2410wdt_cpufreq_transition(struct notifier_block *nb,
* the watchdog is running.
*/
- s3c2410wdt_keepalive();
+ s3c2410wdt_keepalive(&s3c2410_wdd);
} else if (val == CPUFREQ_POSTCHANGE) {
- s3c2410wdt_stop();
+ s3c2410wdt_stop(&s3c2410_wdd);
- ret = s3c2410wdt_set_heartbeat(tmr_margin);
+ ret = s3c2410wdt_set_heartbeat(&s3c2410_wdd, s3c2410_wdd.timeout);
if (ret >= 0)
- s3c2410wdt_start();
+ s3c2410wdt_start(&s3c2410_wdd);
else
goto err;
}
@@ -365,7 +267,8 @@ done:
return 0;
err:
- dev_err(wdt_dev, "cannot set new value for timeout %d\n", tmr_margin);
+ dev_err(wdt_dev, "cannot set new value for timeout %d\n",
+ s3c2410_wdd.timeout);
return ret;
}
@@ -396,10 +299,6 @@ static inline void s3c2410wdt_cpufreq_deregister(void)
}
#endif
-
-
-/* device interface */
-
static int __devinit s3c2410wdt_probe(struct platform_device *pdev)
{
struct device *dev;
@@ -466,8 +365,8 @@ static int __devinit s3c2410wdt_probe(struct platform_device *pdev)
/* see if we can actually set the requested timer margin, and if
* not, try the default value */
- if (s3c2410wdt_set_heartbeat(tmr_margin)) {
- started = s3c2410wdt_set_heartbeat(
+ if (s3c2410wdt_set_heartbeat(&s3c2410_wdd, tmr_margin)) {
+ started = s3c2410wdt_set_heartbeat(&s3c2410_wdd,
CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME);
if (started == 0)
@@ -479,22 +378,21 @@ static int __devinit s3c2410wdt_probe(struct platform_device *pdev)
"cannot start\n");
}
- ret = misc_register(&s3c2410wdt_miscdev);
+ ret = watchdog_register_device(&s3c2410_wdd);
if (ret) {
- dev_err(dev, "cannot register miscdev on minor=%d (%d)\n",
- WATCHDOG_MINOR, ret);
+ dev_err(dev, "cannot register watchdog (%d)\n", ret);
goto err_cpufreq;
}
if (tmr_atboot && started == 0) {
dev_info(dev, "starting watchdog timer\n");
- s3c2410wdt_start();
+ s3c2410wdt_start(&s3c2410_wdd);
} else if (!tmr_atboot) {
/* if we're not enabling the watchdog, then ensure it is
* disabled if it has been left running from the bootloader
* or other source */
- s3c2410wdt_stop();
+ s3c2410wdt_stop(&s3c2410_wdd);
}
/* print out a statement of readiness */
@@ -530,7 +428,7 @@ static int __devinit s3c2410wdt_probe(struct platform_device *pdev)
static int __devexit s3c2410wdt_remove(struct platform_device *dev)
{
- misc_deregister(&s3c2410wdt_miscdev);
+ watchdog_unregister_device(&s3c2410_wdd);
s3c2410wdt_cpufreq_deregister();
@@ -550,7 +448,7 @@ static int __devexit s3c2410wdt_remove(struct platform_device *dev)
static void s3c2410wdt_shutdown(struct platform_device *dev)
{
- s3c2410wdt_stop();
+ s3c2410wdt_stop(&s3c2410_wdd);
}
#ifdef CONFIG_PM
@@ -565,7 +463,7 @@ static int s3c2410wdt_suspend(struct platform_device *dev, pm_message_t state)
wtdat_save = readl(wdt_base + S3C2410_WTDAT);
/* Note that WTCNT doesn't need to be saved. */
- s3c2410wdt_stop();
+ s3c2410wdt_stop(&s3c2410_wdd);
return 0;
}
--
1.7.2.5
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