struct sch56xx_watchdog_data {
u16 addr;
- u32 revision;
struct mutex *io_lock;
- struct mutex watchdog_lock;
- struct list_head list; /* member of the watchdog_data_list */
- struct kref kref;
- struct miscdevice watchdog_miscdev;
- unsigned long watchdog_is_open;
- char watchdog_name[10]; /* must be unique to avoid sysfs conflict */
- char watchdog_expect_close;
+ struct watchdog_info wdinfo;
+ struct watchdog_device wddev;
u8 watchdog_preset;
u8 watchdog_control;
u8 watchdog_output_enable;
static struct platform_device *sch56xx_pdev;
-/*
- * Somewhat ugly :( global data pointer list with all sch56xx devices, so that
- * we can find our device data as when using misc_register there is no other
- * method to get to ones device data from the open fop.
- */
-static LIST_HEAD(watchdog_data_list);
-/* Note this lock not only protect list access, but also data.kref access */
-static DEFINE_MUTEX(watchdog_data_mutex);
-
/* Super I/O functions */
static inline int superio_inb(int base, int reg)
{
* Watchdog routines
*/
-/*
- * Release our data struct when the platform device has been released *and*
- * all references to our watchdog device are released.
- */
-static void sch56xx_watchdog_release_resources(struct kref *r)
-{
- struct sch56xx_watchdog_data *data =
- container_of(r, struct sch56xx_watchdog_data, kref);
- kfree(data);
-}
-
-static int watchdog_set_timeout(struct sch56xx_watchdog_data *data,
- int timeout)
+static int watchdog_set_timeout(struct watchdog_device *wddev,
+ unsigned int timeout)
{
- int ret, resolution;
+ struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
+ unsigned int resolution;
u8 control;
+ int ret;
/* 1 second or 60 second resolution? */
if (timeout <= 255)
if (timeout < resolution || timeout > (resolution * 255))
return -EINVAL;
- mutex_lock(&data->watchdog_lock);
- if (!data->addr) {
- ret = -ENODEV;
- goto leave;
- }
-
if (resolution == 1)
control = data->watchdog_control | SCH56XX_WDOG_TIME_BASE_SEC;
else
control);
mutex_unlock(data->io_lock);
if (ret)
- goto leave;
+ return ret;
data->watchdog_control = control;
}
* the watchdog countdown.
*/
data->watchdog_preset = DIV_ROUND_UP(timeout, resolution);
+ wddev->timeout = data->watchdog_preset * resolution;
- ret = data->watchdog_preset * resolution;
-leave:
- mutex_unlock(&data->watchdog_lock);
- return ret;
-}
-
-static int watchdog_get_timeout(struct sch56xx_watchdog_data *data)
-{
- int timeout;
-
- mutex_lock(&data->watchdog_lock);
- if (data->watchdog_control & SCH56XX_WDOG_TIME_BASE_SEC)
- timeout = data->watchdog_preset;
- else
- timeout = data->watchdog_preset * 60;
- mutex_unlock(&data->watchdog_lock);
-
- return timeout;
+ return 0;
}
-static int watchdog_start(struct sch56xx_watchdog_data *data)
+static int watchdog_start(struct watchdog_device *wddev)
{
+ struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
int ret;
u8 val;
- mutex_lock(&data->watchdog_lock);
- if (!data->addr) {
- ret = -ENODEV;
- goto leave_unlock_watchdog;
- }
-
/*
* The sch56xx's watchdog cannot really be started / stopped
* it is always running, but we can avoid the timer expiring
leave:
mutex_unlock(data->io_lock);
-leave_unlock_watchdog:
- mutex_unlock(&data->watchdog_lock);
return ret;
}
-static int watchdog_trigger(struct sch56xx_watchdog_data *data)
+static int watchdog_trigger(struct watchdog_device *wddev)
{
+ struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
int ret;
- mutex_lock(&data->watchdog_lock);
- if (!data->addr) {
- ret = -ENODEV;
- goto leave;
- }
-
/* Reset the watchdog countdown counter */
mutex_lock(data->io_lock);
ret = sch56xx_write_virtual_reg(data->addr, SCH56XX_REG_WDOG_PRESET,
data->watchdog_preset);
mutex_unlock(data->io_lock);
-leave:
- mutex_unlock(&data->watchdog_lock);
+
return ret;
}
-static int watchdog_stop_unlocked(struct sch56xx_watchdog_data *data)
+static int watchdog_stop(struct watchdog_device *wddev)
{
+ struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
int ret = 0;
u8 val;
- if (!data->addr)
- return -ENODEV;
-
if (data->watchdog_output_enable & SCH56XX_WDOG_OUTPUT_ENABLE) {
val = data->watchdog_output_enable &
~SCH56XX_WDOG_OUTPUT_ENABLE;
return ret;
}
-static int watchdog_stop(struct sch56xx_watchdog_data *data)
-{
- int ret;
-
- mutex_lock(&data->watchdog_lock);
- ret = watchdog_stop_unlocked(data);
- mutex_unlock(&data->watchdog_lock);
-
- return ret;
-}
-
-static int watchdog_release(struct inode *inode, struct file *filp)
-{
- struct sch56xx_watchdog_data *data = filp->private_data;
-
- if (data->watchdog_expect_close) {
- watchdog_stop(data);
- data->watchdog_expect_close = 0;
- } else {
- watchdog_trigger(data);
- pr_crit("unexpected close, not stopping watchdog!\n");
- }
-
- clear_bit(0, &data->watchdog_is_open);
-
- mutex_lock(&watchdog_data_mutex);
- kref_put(&data->kref, sch56xx_watchdog_release_resources);
- mutex_unlock(&watchdog_data_mutex);
-
- return 0;
-}
-
-static int watchdog_open(struct inode *inode, struct file *filp)
-{
- struct sch56xx_watchdog_data *pos, *data = NULL;
- int ret, watchdog_is_open;
-
- /*
- * We get called from drivers/char/misc.c with misc_mtx hold, and we
- * call misc_register() from sch56xx_watchdog_probe() with
- * watchdog_data_mutex hold, as misc_register() takes the misc_mtx
- * lock, this is a possible deadlock, so we use mutex_trylock here.
- */
- if (!mutex_trylock(&watchdog_data_mutex))
- return -ERESTARTSYS;
- list_for_each_entry(pos, &watchdog_data_list, list) {
- if (pos->watchdog_miscdev.minor == iminor(inode)) {
- data = pos;
- break;
- }
- }
- /* Note we can never not have found data, so we don't check for this */
- watchdog_is_open = test_and_set_bit(0, &data->watchdog_is_open);
- if (!watchdog_is_open)
- kref_get(&data->kref);
- mutex_unlock(&watchdog_data_mutex);
-
- if (watchdog_is_open)
- return -EBUSY;
-
- filp->private_data = data;
-
- /* Start the watchdog */
- ret = watchdog_start(data);
- if (ret) {
- watchdog_release(inode, filp);
- return ret;
- }
-
- return nonseekable_open(inode, filp);
-}
-
-static ssize_t watchdog_write(struct file *filp, const char __user *buf,
- size_t count, loff_t *offset)
-{
- int ret;
- struct sch56xx_watchdog_data *data = filp->private_data;
-
- if (count) {
- if (!nowayout) {
- size_t i;
-
- /* Clear it in case it was set with a previous write */
- data->watchdog_expect_close = 0;
-
- for (i = 0; i != count; i++) {
- char c;
- if (get_user(c, buf + i))
- return -EFAULT;
- if (c == 'V')
- data->watchdog_expect_close = 1;
- }
- }
- ret = watchdog_trigger(data);
- if (ret)
- return ret;
- }
- return count;
-}
-
-static long watchdog_ioctl(struct file *filp, unsigned int cmd,
- unsigned long arg)
-{
- struct watchdog_info ident = {
- .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT,
- .identity = "sch56xx watchdog"
- };
- int i, ret = 0;
- struct sch56xx_watchdog_data *data = filp->private_data;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- ident.firmware_version = data->revision;
- if (!nowayout)
- ident.options |= WDIOF_MAGICCLOSE;
- if (copy_to_user((void __user *)arg, &ident, sizeof(ident)))
- ret = -EFAULT;
- break;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- ret = put_user(0, (int __user *)arg);
- break;
-
- case WDIOC_KEEPALIVE:
- ret = watchdog_trigger(data);
- break;
-
- case WDIOC_GETTIMEOUT:
- i = watchdog_get_timeout(data);
- ret = put_user(i, (int __user *)arg);
- break;
-
- case WDIOC_SETTIMEOUT:
- if (get_user(i, (int __user *)arg)) {
- ret = -EFAULT;
- break;
- }
- ret = watchdog_set_timeout(data, i);
- if (ret >= 0)
- ret = put_user(ret, (int __user *)arg);
- break;
-
- case WDIOC_SETOPTIONS:
- if (get_user(i, (int __user *)arg)) {
- ret = -EFAULT;
- break;
- }
-
- if (i & WDIOS_DISABLECARD)
- ret = watchdog_stop(data);
- else if (i & WDIOS_ENABLECARD)
- ret = watchdog_trigger(data);
- else
- ret = -EINVAL;
- break;
-
- default:
- ret = -ENOTTY;
- }
- return ret;
-}
-
-static const struct file_operations watchdog_fops = {
- .owner = THIS_MODULE,
- .llseek = no_llseek,
- .open = watchdog_open,
- .release = watchdog_release,
- .write = watchdog_write,
- .unlocked_ioctl = watchdog_ioctl,
+static const struct watchdog_ops watchdog_ops = {
+ .owner = THIS_MODULE,
+ .start = watchdog_start,
+ .stop = watchdog_stop,
+ .ping = watchdog_trigger,
+ .set_timeout = watchdog_set_timeout,
};
-struct sch56xx_watchdog_data *sch56xx_watchdog_register(
+struct sch56xx_watchdog_data *sch56xx_watchdog_register(struct device *parent,
u16 addr, u32 revision, struct mutex *io_lock, int check_enabled)
{
struct sch56xx_watchdog_data *data;
- int i, err, control, output_enable;
- const int watchdog_minors[] = { WATCHDOG_MINOR, 212, 213, 214, 215 };
+ int err, control, output_enable;
/* Cache the watchdog registers */
mutex_lock(io_lock);
return NULL;
data->addr = addr;
- data->revision = revision;
data->io_lock = io_lock;
- data->watchdog_control = control;
- data->watchdog_output_enable = output_enable;
- mutex_init(&data->watchdog_lock);
- INIT_LIST_HEAD(&data->list);
- kref_init(&data->kref);
-
- err = watchdog_set_timeout(data, 60);
- if (err < 0)
- goto error;
- /*
- * We take the data_mutex lock early so that watchdog_open() cannot
- * run when misc_register() has completed, but we've not yet added
- * our data to the watchdog_data_list.
- */
- mutex_lock(&watchdog_data_mutex);
- for (i = 0; i < ARRAY_SIZE(watchdog_minors); i++) {
- /* Register our watchdog part */
- snprintf(data->watchdog_name, sizeof(data->watchdog_name),
- "watchdog%c", (i == 0) ? '\0' : ('0' + i));
- data->watchdog_miscdev.name = data->watchdog_name;
- data->watchdog_miscdev.fops = &watchdog_fops;
- data->watchdog_miscdev.minor = watchdog_minors[i];
- err = misc_register(&data->watchdog_miscdev);
- if (err == -EBUSY)
- continue;
- if (err)
- break;
+ strlcpy(data->wdinfo.identity, "sch56xx watchdog",
+ sizeof(data->wdinfo.identity));
+ data->wdinfo.firmware_version = revision;
+ data->wdinfo.options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT;
+ if (!nowayout)
+ data->wdinfo.options |= WDIOF_MAGICCLOSE;
+
+ data->wddev.info = &data->wdinfo;
+ data->wddev.ops = &watchdog_ops;
+ data->wddev.parent = parent;
+ data->wddev.timeout = 60;
+ data->wddev.min_timeout = 1;
+ data->wddev.max_timeout = 255 * 60;
+ if (nowayout)
+ data->wddev.status |= WDOG_NO_WAY_OUT;
+ if (output_enable & SCH56XX_WDOG_OUTPUT_ENABLE)
+ data->wddev.status |= WDOG_ACTIVE;
+
+ /* Since the watchdog uses a downcounter there is no register to read
+ the BIOS set timeout from (if any was set at all) ->
+ Choose a preset which will give us a 1 minute timeout */
+ if (control & SCH56XX_WDOG_TIME_BASE_SEC)
+ data->watchdog_preset = 60; /* seconds */
+ else
+ data->watchdog_preset = 1; /* minute */
- list_add(&data->list, &watchdog_data_list);
- pr_info("Registered /dev/%s chardev major 10, minor: %d\n",
- data->watchdog_name, watchdog_minors[i]);
- break;
- }
- mutex_unlock(&watchdog_data_mutex);
+ data->watchdog_control = control;
+ data->watchdog_output_enable = output_enable;
+ watchdog_set_drvdata(&data->wddev, data);
+ err = watchdog_register_device(&data->wddev);
if (err) {
pr_err("Registering watchdog chardev: %d\n", err);
- goto error;
- }
- if (i == ARRAY_SIZE(watchdog_minors)) {
- pr_warn("Couldn't register watchdog (no free minor)\n");
- goto error;
+ kfree(data);
+ return NULL;
}
return data;
-
-error:
- kfree(data);
- return NULL;
}
EXPORT_SYMBOL(sch56xx_watchdog_register);
void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data)
{
- mutex_lock(&watchdog_data_mutex);
- misc_deregister(&data->watchdog_miscdev);
- list_del(&data->list);
- mutex_unlock(&watchdog_data_mutex);
-
- mutex_lock(&data->watchdog_lock);
- if (data->watchdog_is_open) {
- pr_warn("platform device unregistered with watchdog "
- "open! Stopping watchdog.\n");
- watchdog_stop_unlocked(data);
- }
- /* Tell the wdog start/stop/trigger functions our dev is gone */
- data->addr = 0;
- data->io_lock = NULL;
- mutex_unlock(&data->watchdog_lock);
-
- mutex_lock(&watchdog_data_mutex);
- kref_put(&data->kref, sch56xx_watchdog_release_resources);
- mutex_unlock(&watchdog_data_mutex);
+ watchdog_unregister_device(&data->wddev);
+ kfree(data);
}
EXPORT_SYMBOL(sch56xx_watchdog_unregister);
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