[PATCH 2/2 v2] watchdog/coh901327: convert to use watchdog core
Linus Walleij
linus.walleij at stericsson.com
Fri Mar 16 04:14:12 EDT 2012
From: Linus Walleij <linus.walleij at linaro.org>
This converts the COH901327 watchdog to use the watchdog core.
I followed Wolframs document, looked at some other drivers and
tested it on the U300.
Cc: Wolfram Sang <w.sang at pengutronix.de>
Signed-off-by: Linus Walleij <linus.walleij at linaro.org>
---
ChangeLog v1->v2:
- Rebased on top of Viresh's GETTIMELEFT patch and consequently
dropped the ioctl() call.
---
drivers/watchdog/Kconfig | 1 +
drivers/watchdog/coh901327_wdt.c | 192 +++++++++++---------------------------
2 files changed, 56 insertions(+), 137 deletions(-)
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index df9e8f0..2a4c640 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -283,6 +283,7 @@ config COH901327_WATCHDOG
bool "ST-Ericsson COH 901 327 watchdog"
depends on ARCH_U300
default y if MACH_U300
+ select WATCHDOG_CORE
help
Say Y here to include Watchdog timer support for the
watchdog embedded into the ST-Ericsson U300 series platforms.
diff --git a/drivers/watchdog/coh901327_wdt.c b/drivers/watchdog/coh901327_wdt.c
index 5b89f7d..7f0cbeb 100644
--- a/drivers/watchdog/coh901327_wdt.c
+++ b/drivers/watchdog/coh901327_wdt.c
@@ -8,17 +8,15 @@
*/
#include <linux/module.h>
#include <linux/types.h>
-#include <linux/fs.h>
-#include <linux/miscdevice.h>
#include <linux/watchdog.h>
#include <linux/interrupt.h>
#include <linux/pm.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/bitops.h>
-#include <linux/uaccess.h>
#include <linux/clk.h>
#include <linux/delay.h>
+#include <linux/err.h>
#define DRV_NAME "WDOG COH 901 327"
@@ -74,8 +72,6 @@ static resource_size_t phybase;
static resource_size_t physize;
static int irq;
static void __iomem *virtbase;
-static unsigned long coh901327_users;
-static unsigned long boot_status;
static struct device *parent;
/*
@@ -155,30 +151,31 @@ static void coh901327_disable(void)
__func__, val);
}
-static void coh901327_start(void)
+static int coh901327_start(struct watchdog_device *wdt_dev)
{
coh901327_enable(margin * 100);
+ return 0;
+}
+
+static int coh901327_stop(struct watchdog_device *wdt_dev)
+{
+ coh901327_disable();
+ return 0;
}
-static void coh901327_keepalive(void)
+static int coh901327_ping(struct watchdog_device *wdd)
{
clk_enable(clk);
/* Feed the watchdog */
writew(U300_WDOG_FR_FEED_RESTART_TIMER,
virtbase + U300_WDOG_FR);
clk_disable(clk);
+ return 0;
}
-static int coh901327_settimeout(int time)
+static int coh901327_settimeout(struct watchdog_device *wdt_dev,
+ unsigned int time)
{
- /*
- * Max margin is 327 since the 10ms
- * timeout register is max
- * 0x7FFF = 327670ms ~= 327s.
- */
- if (time <= 0 || time > 327)
- return -EINVAL;
-
margin = time;
clk_enable(clk);
/* Set new timeout value */
@@ -190,6 +187,23 @@ static int coh901327_settimeout(int time)
return 0;
}
+static unsigned int coh901327_gettimeleft(struct watchdog_device *wdt_dev)
+{
+ u16 val;
+
+ clk_enable(clk);
+ /* Read repeatedly until the value is stable! */
+ val = readw(virtbase + U300_WDOG_CR);
+ while (val & U300_WDOG_CR_VALID_IND)
+ val = readw(virtbase + U300_WDOG_CR);
+ val &= U300_WDOG_CR_COUNT_VALUE_MASK;
+ clk_disable(clk);
+ if (val != 0)
+ val /= 100;
+
+ return val;
+}
+
/*
* This interrupt occurs 10 ms before the watchdog WILL bark.
*/
@@ -218,130 +232,35 @@ static irqreturn_t coh901327_interrupt(int irq, void *data)
return IRQ_HANDLED;
}
-/*
- * Allow only one user (daemon) to open the watchdog
- */
-static int coh901327_open(struct inode *inode, struct file *file)
-{
- if (test_and_set_bit(1, &coh901327_users))
- return -EBUSY;
- coh901327_start();
- return nonseekable_open(inode, file);
-}
-
-static int coh901327_release(struct inode *inode, struct file *file)
-{
- clear_bit(1, &coh901327_users);
- coh901327_disable();
- return 0;
-}
-
-static ssize_t coh901327_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
-{
- if (len)
- coh901327_keepalive();
- return len;
-}
-
-static long coh901327_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- int ret = -ENOTTY;
- u16 val;
- int time;
- int new_options;
- union {
- struct watchdog_info __user *ident;
- int __user *i;
- } uarg;
- static const struct watchdog_info ident = {
- .options = WDIOF_CARDRESET |
- WDIOF_SETTIMEOUT |
- WDIOF_KEEPALIVEPING,
- .identity = "COH 901 327 Watchdog",
- .firmware_version = 1,
- };
- uarg.i = (int __user *)arg;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- ret = copy_to_user(uarg.ident, &ident,
- sizeof(ident)) ? -EFAULT : 0;
- break;
-
- case WDIOC_GETSTATUS:
- ret = put_user(0, uarg.i);
- break;
-
- case WDIOC_GETBOOTSTATUS:
- ret = put_user(boot_status, uarg.i);
- break;
-
- case WDIOC_SETOPTIONS:
- ret = get_user(new_options, uarg.i);
- if (ret)
- break;
- if (new_options & WDIOS_DISABLECARD)
- coh901327_disable();
- if (new_options & WDIOS_ENABLECARD)
- coh901327_start();
- ret = 0;
- break;
-
- case WDIOC_KEEPALIVE:
- coh901327_keepalive();
- ret = 0;
- break;
-
- case WDIOC_SETTIMEOUT:
- ret = get_user(time, uarg.i);
- if (ret)
- break;
-
- ret = coh901327_settimeout(time);
- if (ret)
- break;
- /* Then fall through to return set value */
-
- case WDIOC_GETTIMEOUT:
- ret = put_user(margin, uarg.i);
- break;
-
- case WDIOC_GETTIMELEFT:
- clk_enable(clk);
- /* Read repeatedly until the value is stable! */
- val = readw(virtbase + U300_WDOG_CR);
- while (val & U300_WDOG_CR_VALID_IND)
- val = readw(virtbase + U300_WDOG_CR);
- val &= U300_WDOG_CR_COUNT_VALUE_MASK;
- clk_disable(clk);
- if (val != 0)
- val /= 100;
- ret = put_user(val, uarg.i);
- break;
- }
- return ret;
-}
+static const struct watchdog_info coh901327_ident = {
+ .options = WDIOF_CARDRESET | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
+ .identity = DRV_NAME,
+};
-static const struct file_operations coh901327_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = coh901327_write,
- .unlocked_ioctl = coh901327_ioctl,
- .open = coh901327_open,
- .release = coh901327_release,
+static struct watchdog_ops coh901327_ops = {
+ .owner = THIS_MODULE,
+ .start = coh901327_start,
+ .stop = coh901327_stop,
+ .ping = coh901327_ping,
+ .set_timeout = coh901327_settimeout,
+ .get_timeleft = coh901327_gettimeleft,
};
-static struct miscdevice coh901327_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &coh901327_fops,
+static struct watchdog_device coh901327_wdt = {
+ .info = &coh901327_ident,
+ .ops = &coh901327_ops,
+ /*
+ * Max margin is 327 since the 10ms
+ * timeout register is max
+ * 0x7FFF = 327670ms ~= 327s.
+ */
+ .min_timeout = 0,
+ .max_timeout = 327,
};
static int __exit coh901327_remove(struct platform_device *pdev)
{
- misc_deregister(&coh901327_miscdev);
+ watchdog_unregister_device(&coh901327_wdt);
coh901327_disable();
free_irq(irq, pdev);
clk_put(clk);
@@ -350,7 +269,6 @@ static int __exit coh901327_remove(struct platform_device *pdev)
return 0;
}
-
static int __init coh901327_probe(struct platform_device *pdev)
{
int ret;
@@ -393,7 +311,7 @@ static int __init coh901327_probe(struct platform_device *pdev)
case U300_WDOG_SR_STATUS_TIMED_OUT:
dev_info(&pdev->dev,
"watchdog timed out since last chip reset!\n");
- boot_status = WDIOF_CARDRESET;
+ coh901327_wdt.bootstatus |= WDIOF_CARDRESET;
/* Status will be cleared below */
break;
case U300_WDOG_SR_STATUS_NORMAL:
@@ -435,7 +353,7 @@ static int __init coh901327_probe(struct platform_device *pdev)
clk_disable(clk);
- ret = misc_register(&coh901327_miscdev);
+ ret = watchdog_register_device(&coh901327_wdt);
if (ret == 0)
dev_info(&pdev->dev,
"initialized. timer margin=%d sec\n", margin);
@@ -547,4 +465,4 @@ module_param(margin, int, 0);
MODULE_PARM_DESC(margin, "Watchdog margin in seconds (default 60s)");
MODULE_LICENSE("GPL");
-MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
+MODULE_ALIAS("platform:coh901327-watchdog");
--
1.7.9.2
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