lkml.org 
[lkml]   [2011]   [Nov]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] watchdog: Convert wm831x driver to watchdog core
Date
Fairly large code churn but not much doing with that and the overall
result is a definite win.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
---
drivers/watchdog/Kconfig | 1 +
drivers/watchdog/wm831x_wdt.c | 318 ++++++++++++++---------------------------
2 files changed, 106 insertions(+), 213 deletions(-)

diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index 884f369..37dae3c 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -66,6 +66,7 @@ config SOFT_WATCHDOG
config WM831X_WATCHDOG
tristate "WM831x watchdog"
depends on MFD_WM831X
+ select WATCHDOG_CORE
help
Support for the watchdog in the WM831x AudioPlus PMICs. When
the watchdog triggers the system will be reset.
diff --git a/drivers/watchdog/wm831x_wdt.c b/drivers/watchdog/wm831x_wdt.c
index 871caea..7be3855 100644
--- a/drivers/watchdog/wm831x_wdt.c
+++ b/drivers/watchdog/wm831x_wdt.c
@@ -12,8 +12,7 @@
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/kernel.h>
-#include <linux/fs.h>
-#include <linux/miscdevice.h>
+#include <linux/slab.h>
#include <linux/platform_device.h>
#include <linux/watchdog.h>
#include <linux/uaccess.h>
@@ -29,19 +28,19 @@ MODULE_PARM_DESC(nowayout,
"Watchdog cannot be stopped once started (default="
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");

-static unsigned long wm831x_wdt_users;
-static struct miscdevice wm831x_wdt_miscdev;
-static int wm831x_wdt_expect_close;
-static DEFINE_MUTEX(wdt_mutex);
-static struct wm831x *wm831x;
-static unsigned int update_gpio;
-static unsigned int update_state;
+struct wm831x_wdt_drvdata {
+ struct watchdog_device wdt;
+ struct wm831x *wm831x;
+ struct mutex lock;
+ int update_gpio;
+ int update_state;
+};

/* We can't use the sub-second values here but they're included
* for completeness. */
static struct {
- int time; /* Seconds */
- u16 val; /* WDOG_TO value */
+ unsigned int time; /* Seconds */
+ u16 val; /* WDOG_TO value */
} wm831x_wdt_cfgs[] = {
{ 1, 2 },
{ 2, 3 },
@@ -52,32 +51,13 @@ static struct {
{ 33, 7 }, /* Actually 32.768s so include both, others round down */
};

-static int wm831x_wdt_set_timeout(struct wm831x *wm831x, u16 value)
-{
- int ret;
-
- mutex_lock(&wdt_mutex);
-
- ret = wm831x_reg_unlock(wm831x);
- if (ret == 0) {
- ret = wm831x_set_bits(wm831x, WM831X_WATCHDOG,
- WM831X_WDOG_TO_MASK, value);
- wm831x_reg_lock(wm831x);
- } else {
- dev_err(wm831x->dev, "Failed to unlock security key: %d\n",
- ret);
- }
-
- mutex_unlock(&wdt_mutex);
-
- return ret;
-}
-
-static int wm831x_wdt_start(struct wm831x *wm831x)
+static int wm831x_wdt_start(struct watchdog_device *wdt_dev)
{
+ struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct wm831x *wm831x = driver_data->wm831x;
int ret;

- mutex_lock(&wdt_mutex);
+ mutex_lock(&driver_data->lock);

ret = wm831x_reg_unlock(wm831x);
if (ret == 0) {
@@ -89,16 +69,18 @@ static int wm831x_wdt_start(struct wm831x *wm831x)
ret);
}

- mutex_unlock(&wdt_mutex);
+ mutex_unlock(&driver_data->lock);

return ret;
}

-static int wm831x_wdt_stop(struct wm831x *wm831x)
+static int wm831x_wdt_stop(struct watchdog_device *wdt_dev)
{
+ struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct wm831x *wm831x = driver_data->wm831x;
int ret;

- mutex_lock(&wdt_mutex);
+ mutex_lock(&driver_data->lock);

ret = wm831x_reg_unlock(wm831x);
if (ret == 0) {
@@ -110,26 +92,28 @@ static int wm831x_wdt_stop(struct wm831x *wm831x)
ret);
}

- mutex_unlock(&wdt_mutex);
+ mutex_unlock(&driver_data->lock);

return ret;
}

-static int wm831x_wdt_kick(struct wm831x *wm831x)
+static int wm831x_wdt_ping(struct watchdog_device *wdt_dev)
{
+ struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct wm831x *wm831x = driver_data->wm831x;
int ret;
u16 reg;

- mutex_lock(&wdt_mutex);
+ mutex_lock(&driver_data->lock);

- if (update_gpio) {
- gpio_set_value_cansleep(update_gpio, update_state);
- update_state = !update_state;
+ if (driver_data->update_gpio) {
+ gpio_set_value_cansleep(driver_data->update_gpio,
+ driver_data->update_state);
+ driver_data->update_state = !driver_data->update_state;
ret = 0;
goto out;
}

-
reg = wm831x_reg_read(wm831x, WM831X_WATCHDOG);

if (!(reg & WM831X_WDOG_RST_SRC)) {
@@ -150,182 +134,59 @@ static int wm831x_wdt_kick(struct wm831x *wm831x)
}

out:
- mutex_unlock(&wdt_mutex);
+ mutex_unlock(&driver_data->lock);

return ret;
}

-static int wm831x_wdt_open(struct inode *inode, struct file *file)
+static int wm831x_wdt_set_timeout(struct watchdog_device *wdt_dev,
+ unsigned int timeout)
{
- int ret;
-
- if (!wm831x)
- return -ENODEV;
-
- if (test_and_set_bit(0, &wm831x_wdt_users))
- return -EBUSY;
+ struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
+ struct wm831x *wm831x = driver_data->wm831x;
+ int ret, i;

- ret = wm831x_wdt_start(wm831x);
- if (ret != 0)
- return ret;
-
- return nonseekable_open(inode, file);
-}
+ for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)
+ if (wm831x_wdt_cfgs[i].time == timeout)
+ break;
+ if (i == ARRAY_SIZE(wm831x_wdt_cfgs))
+ ret = -EINVAL;

-static int wm831x_wdt_release(struct inode *inode, struct file *file)
-{
- if (wm831x_wdt_expect_close)
- wm831x_wdt_stop(wm831x);
- else {
- dev_warn(wm831x->dev, "Watchdog device closed uncleanly\n");
- wm831x_wdt_kick(wm831x);
+ ret = wm831x_reg_unlock(wm831x);
+ if (ret == 0) {
+ ret = wm831x_set_bits(wm831x, WM831X_WATCHDOG,
+ WM831X_WDOG_TO_MASK,
+ wm831x_wdt_cfgs[i].val);
+ wm831x_reg_lock(wm831x);
+ } else {
+ dev_err(wm831x->dev, "Failed to unlock security key: %d\n",
+ ret);
}

- clear_bit(0, &wm831x_wdt_users);
-
- return 0;
-}
-
-static ssize_t wm831x_wdt_write(struct file *file,
- const char __user *data, size_t count,
- loff_t *ppos)
-{
- size_t i;
-
- if (count) {
- wm831x_wdt_kick(wm831x);
-
- if (!nowayout) {
- /* In case it was set long ago */
- wm831x_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')
- wm831x_wdt_expect_close = 42;
- }
- }
- }
- return count;
+ return ret;
}

-static const struct watchdog_info ident = {
+static const struct watchdog_info wm831x_wdt_info = {
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
.identity = "WM831x Watchdog",
};

-static long wm831x_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- 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 = wm831x_wdt_start(wm831x);
-
- if (options == WDIOS_ENABLECARD)
- ret = wm831x_wdt_stop(wm831x);
- break;
- }
-
- case WDIOC_KEEPALIVE:
- ret = wm831x_wdt_kick(wm831x);
- break;
-
- case WDIOC_SETTIMEOUT:
- ret = get_user(time, p);
- if (ret)
- break;
-
- if (time == 0) {
- if (nowayout)
- ret = -EINVAL;
- else
- wm831x_wdt_stop(wm831x);
- break;
- }
-
- for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)
- if (wm831x_wdt_cfgs[i].time == time)
- break;
- if (i == ARRAY_SIZE(wm831x_wdt_cfgs))
- ret = -EINVAL;
- else
- ret = wm831x_wdt_set_timeout(wm831x,
- wm831x_wdt_cfgs[i].val);
- break;
-
- case WDIOC_GETTIMEOUT:
- reg = wm831x_reg_read(wm831x, WM831X_WATCHDOG);
- reg &= WM831X_WDOG_TO_MASK;
- for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)
- if (wm831x_wdt_cfgs[i].val == reg)
- break;
- if (i == ARRAY_SIZE(wm831x_wdt_cfgs)) {
- dev_warn(wm831x->dev,
- "Unknown watchdog configuration: %x\n", reg);
- ret = -EINVAL;
- } else
- ret = put_user(wm831x_wdt_cfgs[i].time, p);
-
- }
-
- return ret;
-}
-
-static const struct file_operations wm831x_wdt_fops = {
+static const struct watchdog_ops wm831x_wdt_ops = {
.owner = THIS_MODULE,
- .llseek = no_llseek,
- .write = wm831x_wdt_write,
- .unlocked_ioctl = wm831x_wdt_ioctl,
- .open = wm831x_wdt_open,
- .release = wm831x_wdt_release,
-};
-
-static struct miscdevice wm831x_wdt_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &wm831x_wdt_fops,
+ .start = wm831x_wdt_start,
+ .stop = wm831x_wdt_stop,
+ .ping = wm831x_wdt_ping,
+ .set_timeout = wm831x_wdt_set_timeout,
};

static int __devinit wm831x_wdt_probe(struct platform_device *pdev)
{
+ struct wm831x *wm831x = dev_get_drvdata(pdev->dev.parent);
struct wm831x_pdata *chip_pdata;
struct wm831x_watchdog_pdata *pdata;
- int reg, ret;
-
- if (wm831x) {
- dev_err(&pdev->dev, "wm831x watchdog already registered\n");
- return -EBUSY;
- }
-
- wm831x = dev_get_drvdata(pdev->dev.parent);
+ struct wm831x_wdt_drvdata *driver_data;
+ struct watchdog_device *wm831x_wdt;
+ int reg, ret, i;

ret = wm831x_reg_read(wm831x, WM831X_WATCHDOG);
if (ret < 0) {
@@ -338,6 +199,36 @@ static int __devinit wm831x_wdt_probe(struct platform_device *pdev)
if (reg & WM831X_WDOG_DEBUG)
dev_warn(wm831x->dev, "Watchdog is paused\n");

+ driver_data = kzalloc(sizeof(*driver_data), GFP_KERNEL);
+ if (!driver_data) {
+ dev_err(wm831x->dev, "Unable to alloacate watchdog device\n");
+ ret = -ENOMEM;
+ goto err;
+ }
+
+ mutex_init(&driver_data->lock);
+ driver_data->wm831x = wm831x;
+
+ wm831x_wdt = &driver_data->wdt;
+
+ wm831x_wdt->info = &wm831x_wdt_info;
+ wm831x_wdt->ops = &wm831x_wdt_ops;
+ watchdog_set_drvdata(wm831x_wdt, driver_data);
+
+ if (nowayout)
+ wm831x_wdt->status |= WDOG_NO_WAY_OUT;
+
+ reg = wm831x_reg_read(wm831x, WM831X_WATCHDOG);
+ reg &= WM831X_WDOG_TO_MASK;
+ for (i = 0; i < ARRAY_SIZE(wm831x_wdt_cfgs); i++)
+ if (wm831x_wdt_cfgs[i].val == reg)
+ break;
+ if (i == ARRAY_SIZE(wm831x_wdt_cfgs))
+ dev_warn(wm831x->dev,
+ "Unknown watchdog timeout: %x\n", reg);
+ else
+ wm831x_wdt->timeout = wm831x_wdt_cfgs[i].time;
+
/* Apply any configuration */
if (pdev->dev.parent->platform_data) {
chip_pdata = pdev->dev.parent->platform_data;
@@ -361,7 +252,7 @@ static int __devinit wm831x_wdt_probe(struct platform_device *pdev)
dev_err(wm831x->dev,
"Failed to request update GPIO: %d\n",
ret);
- goto err;
+ goto err_alloc;
}

ret = gpio_direction_output(pdata->update_gpio, 0);
@@ -372,7 +263,7 @@ static int __devinit wm831x_wdt_probe(struct platform_device *pdev)
goto err_gpio;
}

- update_gpio = pdata->update_gpio;
+ driver_data->update_gpio = pdata->update_gpio;

/* Make sure the watchdog takes hardware updates */
reg |= WM831X_WDOG_RST_SRC;
@@ -389,33 +280,34 @@ static int __devinit wm831x_wdt_probe(struct platform_device *pdev)
}
}

- wm831x_wdt_miscdev.parent = &pdev->dev;
-
- ret = misc_register(&wm831x_wdt_miscdev);
+ ret = watchdog_register_device(&driver_data->wdt);
if (ret != 0) {
- dev_err(wm831x->dev, "Failed to register miscdev: %d\n", ret);
+ dev_err(wm831x->dev, "watchdog_register_device() failed: %d\n",
+ ret);
goto err_gpio;
}

+ dev_set_drvdata(&pdev->dev, driver_data);
+
return 0;

err_gpio:
- if (update_gpio) {
- gpio_free(update_gpio);
- update_gpio = 0;
- }
+ if (driver_data->update_gpio)
+ gpio_free(driver_data->update_gpio);
+err_alloc:
+ kfree(driver_data);
err:
return ret;
}

static int __devexit wm831x_wdt_remove(struct platform_device *pdev)
{
- if (update_gpio) {
- gpio_free(update_gpio);
- update_gpio = 0;
- }
+ struct wm831x_wdt_drvdata *driver_data = dev_get_drvdata(&pdev->dev);
+
+ watchdog_unregister_device(&driver_data->wdt);

- misc_deregister(&wm831x_wdt_miscdev);
+ if (driver_data->update_gpio)
+ gpio_free(driver_data->update_gpio);

return 0;
}
--
1.7.7.1


\
 
 \ /
  Last update: 2011-11-01 20:53    [W:0.034 / U:42.496 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site