watchdog: Convert wm831x driver to watchdog core

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>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This commit is contained in:
Mark Brown 2011-10-04 16:43:40 +01:00 committed by Wim Van Sebroeck
parent 25dc46e383
commit 00411ee930
2 changed files with 106 additions and 213 deletions

View File

@ -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.

View File

@ -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)
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);
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)
{
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;
struct wm831x_wdt_drvdata *driver_data = watchdog_get_drvdata(wdt_dev);
struct wm831x *wm831x = driver_data->wm831x;
int ret, i;
if (!wm831x)
return -ENODEV;
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;
if (test_and_set_bit(0, &wm831x_wdt_users))
return -EBUSY;
ret = wm831x_wdt_start(wm831x);
if (ret != 0)
return ret;
return nonseekable_open(inode, file);
}
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;
return ret;
}
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;
}
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);
misc_deregister(&wm831x_wdt_miscdev);
watchdog_unregister_device(&driver_data->wdt);
if (driver_data->update_gpio)
gpio_free(driver_data->update_gpio);
return 0;
}