[RFC][PATCH] watchdog: Convert wm8350_wdt driver to watchdog core

From: Axel Lin
Date: Mon Jan 23 2012 - 02:27:46 EST


This patch converts wm8350_wdt driver to use watchdog core APIs.

Signed-off-by: Axel Lin <axel.lin@xxxxxxxxx>
---
Hi Mark,
I don't have this hardware.
I'd appreciate if you can review and test this patch.

Thanks,
Axel

drivers/watchdog/Kconfig | 1 +
drivers/watchdog/wm8350_wdt.c | 213 +++++++----------------------------------
2 files changed, 35 insertions(+), 179 deletions(-)

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 877b107..9dfad61 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -74,6 +74,7 @@ config WM831X_WATCHDOG
config WM8350_WATCHDOG
tristate "WM8350 watchdog"
depends on MFD_WM8350
+ select WATCHDOG_CORE
help
Support for the watchdog in the WM8350 AudioPlus PMIC. When
the watchdog triggers the system will be reset.
diff --git a/drivers/watchdog/wm8350_wdt.c b/drivers/watchdog/wm8350_wdt.c
index 5d7113c..f38da4d 100644
--- a/drivers/watchdog/wm8350_wdt.c
+++ b/drivers/watchdog/wm8350_wdt.c
@@ -12,8 +12,6 @@
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/kernel.h>
-#include <linux/fs.h>
-#include <linux/miscdevice.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <linux/uaccess.h>
@@ -25,36 +23,36 @@ MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

-static unsigned long wm8350_wdt_users;
-static struct miscdevice wm8350_wdt_miscdev;
-static int wm8350_wdt_expect_close;
static DEFINE_MUTEX(wdt_mutex);

static struct {
- int time; /* Seconds */
- u16 val; /* To be set in WM8350_SYSTEM_CONTROL_2 */
+ unsigned int time; /* Seconds */
+ u16 val; /* To be set in WM8350_SYSTEM_CONTROL_2 */
} wm8350_wdt_cfgs[] = {
{ 1, 0x02 },
{ 2, 0x04 },
{ 4, 0x05 },
};

-static struct wm8350 *get_wm8350(void)
+static int wm8350_wdt_set_timeout(struct watchdog_device *wdt_dev,
+ unsigned int timeout)
{
- return dev_get_drvdata(wm8350_wdt_miscdev.parent);
-}
-
-static int wm8350_wdt_set_timeout(struct wm8350 *wm8350, u16 value)
-{
- int ret;
+ struct wm8350 *wm8350 = watchdog_get_drvdata(wdt_dev);
+ int ret, i;
u16 reg;

+ for (i = 0; i < ARRAY_SIZE(wm8350_wdt_cfgs); i++)
+ if (wm8350_wdt_cfgs[i].time == timeout)
+ break;
+ if (i == ARRAY_SIZE(wm8350_wdt_cfgs))
+ return -EINVAL;
+
mutex_lock(&wdt_mutex);
wm8350_reg_unlock(wm8350);

reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
reg &= ~WM8350_WDOG_TO_MASK;
- reg |= value;
+ reg |= wm8350_wdt_cfgs[i].val;
ret = wm8350_reg_write(wm8350, WM8350_SYSTEM_CONTROL_2, reg);

wm8350_reg_lock(wm8350);
@@ -63,8 +61,9 @@ static int wm8350_wdt_set_timeout(struct wm8350 *wm8350, u16 value)
return ret;
}

-static int wm8350_wdt_start(struct wm8350 *wm8350)
+static int wm8350_wdt_start(struct watchdog_device *wdt_dev)
{
+ struct wm8350 *wm8350 = watchdog_get_drvdata(wdt_dev);
int ret;
u16 reg;

@@ -82,8 +81,9 @@ static int wm8350_wdt_start(struct wm8350 *wm8350)
return ret;
}

-static int wm8350_wdt_stop(struct wm8350 *wm8350)
+static int wm8350_wdt_stop(struct watchdog_device *wdt_dev)
{
+ struct wm8350 *wm8350 = watchdog_get_drvdata(wdt_dev);
int ret;
u16 reg;

@@ -100,8 +100,9 @@ static int wm8350_wdt_stop(struct wm8350 *wm8350)
return ret;
}

-static int wm8350_wdt_kick(struct wm8350 *wm8350)
+static int wm8350_wdt_ping(struct watchdog_device *wdt_dev)
{
+ struct wm8350 *wm8350 = watchdog_get_drvdata(wdt_dev);
int ret;
u16 reg;

@@ -115,168 +116,22 @@ static int wm8350_wdt_kick(struct wm8350 *wm8350)
return ret;
}

-static int wm8350_wdt_open(struct inode *inode, struct file *file)
-{
- struct wm8350 *wm8350 = get_wm8350();
- int ret;
-
- if (!wm8350)
- return -ENODEV;
-
- if (test_and_set_bit(0, &wm8350_wdt_users))
- return -EBUSY;
-
- ret = wm8350_wdt_start(wm8350);
- if (ret != 0)
- return ret;
-
- return nonseekable_open(inode, file);
-}
-
-static int wm8350_wdt_release(struct inode *inode, struct file *file)
-{
- struct wm8350 *wm8350 = get_wm8350();
-
- if (wm8350_wdt_expect_close)
- wm8350_wdt_stop(wm8350);
- else {
- dev_warn(wm8350->dev, "Watchdog device closed uncleanly\n");
- wm8350_wdt_kick(wm8350);
- }
-
- clear_bit(0, &wm8350_wdt_users);
-
- return 0;
-}
-
-static ssize_t wm8350_wdt_write(struct file *file,
- const char __user *data, size_t count,
- loff_t *ppos)
-{
- struct wm8350 *wm8350 = get_wm8350();
- size_t i;
-
- if (count) {
- wm8350_wdt_kick(wm8350);
-
- if (!nowayout) {
- /* In case it was set long ago */
- wm8350_wdt_expect_close = 0;
-
- /* scan to see whether or not we got the magic
- character */
- for (i = 0; i != count; i++) {
- char c;
- if (get_user(c, data + i))
- return -EFAULT;
- if (c == 'V')
- wm8350_wdt_expect_close = 42;
- }
- }
- }
- return count;
-}
-
-static const struct watchdog_info ident = {
+static const struct watchdog_info wm8350_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "WM8350 Watchdog",
};

-static long wm8350_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- struct wm8350 *wm8350 = get_wm8350();
- int ret = -ENOTTY, time, i;
- void __user *argp = (void __user *)arg;
- int __user *p = argp;
- u16 reg;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- ret = copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
- break;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- ret = put_user(0, p);
- break;
-
- case WDIOC_SETOPTIONS:
- {
- int options;
-
- if (get_user(options, p))
- return -EFAULT;
-
- ret = -EINVAL;
-
- /* Setting both simultaneously means at least one must fail */
- if (options == WDIOS_DISABLECARD)
- ret = wm8350_wdt_stop(wm8350);
-
- if (options == WDIOS_ENABLECARD)
- ret = wm8350_wdt_start(wm8350);
- break;
- }
-
- case WDIOC_KEEPALIVE:
- ret = wm8350_wdt_kick(wm8350);
- break;
-
- case WDIOC_SETTIMEOUT:
- ret = get_user(time, p);
- if (ret)
- break;
-
- if (time == 0) {
- if (nowayout)
- ret = -EINVAL;
- else
- wm8350_wdt_stop(wm8350);
- break;
- }
-
- for (i = 0; i < ARRAY_SIZE(wm8350_wdt_cfgs); i++)
- if (wm8350_wdt_cfgs[i].time == time)
- break;
- if (i == ARRAY_SIZE(wm8350_wdt_cfgs))
- ret = -EINVAL;
- else
- ret = wm8350_wdt_set_timeout(wm8350,
- wm8350_wdt_cfgs[i].val);
- break;
-
- case WDIOC_GETTIMEOUT:
- reg = wm8350_reg_read(wm8350, WM8350_SYSTEM_CONTROL_2);
- reg &= WM8350_WDOG_TO_MASK;
- for (i = 0; i < ARRAY_SIZE(wm8350_wdt_cfgs); i++)
- if (wm8350_wdt_cfgs[i].val == reg)
- break;
- if (i == ARRAY_SIZE(wm8350_wdt_cfgs)) {
- dev_warn(wm8350->dev,
- "Unknown watchdog configuration: %x\n", reg);
- ret = -EINVAL;
- } else
- ret = put_user(wm8350_wdt_cfgs[i].time, p);
-
- }
-
- return ret;
-}
-
-static const struct file_operations wm8350_wdt_fops = {
+static const struct watchdog_ops wm8350_wdt_ops = {
.owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = wm8350_wdt_write,
- .unlocked_ioctl = wm8350_wdt_ioctl,
- .open = wm8350_wdt_open,
- .release = wm8350_wdt_release,
+ .start = wm8350_wdt_start,
+ .stop = wm8350_wdt_stop,
+ .ping = wm8350_wdt_ping,
+ .set_timeout = wm8350_wdt_set_timeout,
};

-static struct miscdevice wm8350_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &wm8350_wdt_fops,
+static struct watchdog_device wm8350_wdt = {
+ .info = &wm8350_wdt_info,
+ .ops = &wm8350_wdt_ops,
};

static int __devinit wm8350_wdt_probe(struct platform_device *pdev)
@@ -288,18 +143,18 @@ static int __devinit wm8350_wdt_probe(struct platform_device *pdev)
return -ENODEV;
}

- /* Default to 4s timeout */
- wm8350_wdt_set_timeout(wm8350, 0x05);
+ watchdog_set_nowayout(&wm8350_wdt, nowayout);
+ watchdog_set_drvdata(&wm8350_wdt, wm8350);

- wm8350_wdt_miscdev.parent = &pdev->dev;
+ /* Default to 4s timeout */
+ wm8350_wdt_set_timeout(&wm8350_wdt, 4);

- return misc_register(&wm8350_wdt_miscdev);
+ return watchdog_register_device(&wm8350_wdt);
}

static int __devexit wm8350_wdt_remove(struct platform_device *pdev)
{
- misc_deregister(&wm8350_wdt_miscdev);
-
+ watchdog_unregister_device(&wm8350_wdt);
return 0;
}

--
1.7.5.4



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