Hi,
Comments inline.
--- linux-2.6.29.6/drivers/hwmon/w83793.c 2009-07-03 01:41:20.000000000 +0200
+++ linux-2.6.29.6.watchdog/drivers/hwmon/w83793.c 2009-12-04 12:10:55.000000000 +0100
<snip>
@@ -1064,14 +1123,336 @@ static void w83793_init_client(struct i2
/* Start monitoring */
w83793_write_value(client, W83793_REG_CONFIG,
w83793_read_value(client, W83793_REG_CONFIG) | 0x01);
+}
+
+/*
+ * Watchdog routines
+ */
+
+static int watchdog_set_timeout(struct w83793_data *data, int timeout)
+{
+ int ret, stimeout;
+
+ if (timeout > 255)
+ return -EINVAL;
+
timeout is in seconds here, you should do the DIV_ROUND_UP before taking the lock, and
do this check on stimeout.
+ mutex_lock(&data->watchdog_lock);
+ if (!data->client) {
+ ret = -ENODEV;
+ goto leave;
+ }
+
+ stimeout = DIV_ROUND_UP(timeout, 60);
+
+ /* Set Timeout value (in Minutes) */
+ w83793_write_value(data->client, W83793_REG_WDT_TIMEOUT, stimeout);
+
+ ret = stimeout;
+
That should be "stimeout * 60".
+leave:
+ mutex_unlock(&data->watchdog_lock);
+ return ret;
+}
+
+static int watchdog_get_timeout(struct w83793_data *data)
+{
+ int gtimeout;
+
+ mutex_lock(&data->watchdog_lock);
+ if (!data->client)
+ return -ENODEV;
+
+ /* Get Timeout value (in Minutes) */
+ gtimeout = w83793_read_value(data->client, W83793_REG_WDT_TIMEOUT) * 60;
+
+ mutex_unlock(&data->watchdog_lock);
+
+ return gtimeout;
+}
+
+static int watchdog_trigger(struct w83793_data *data)
+{
+ int ret = 0;
+
+ mutex_lock(&data->watchdog_lock);
+ if (!data->client) {
+ ret = -ENODEV;
+ goto leave;
+ }
+
+ /* Set Timeout value (in Minutes) */
+ w83793_write_value(data->client, W83793_REG_WDT_TIMEOUT, timeout);
+
Hmm, and here things get a bit funky, you write the TIMEOUT configuration
register, are you sure this is the right way to do a trigger ?
If so you should remember the configured timeout (the one configured through the
ioctl) in data and write that each trigger.
+leave:
+ mutex_unlock(&data->watchdog_lock);
+ return ret;
+}
+
+static int watchdog_enable(struct w83793_data *data)
+{
+ int ret = 0;
+
+ mutex_lock(&data->watchdog_lock);
+ if (!data->client) {
+ ret = -ENODEV;
+ goto leave;
+ }
+
+ /* Set initial timeout */
+ w83793_write_value(data->client, W83793_REG_WDT_TIMEOUT, timeout);
+
+ /* Enable Soft Watchdog */
+ w83793_write_value(data->client, W83793_REG_WDT_LOCK, 0x55);
+
+leave:
+ mutex_unlock(&data->watchdog_lock);
+ return ret;
+}
+
+static int watchdog_disable(struct w83793_data *data)
+{
+ int ret = 0;
+
+ mutex_lock(&data->watchdog_lock);
+ if (!data->client) {
+ ret = -ENODEV;
+ goto leave;
+ }
+
+ /* Disable Soft Watchdog */
+ w83793_write_value(data->client, W83793_REG_WDT_LOCK, 0xAA);
+
+leave:
+ mutex_unlock(&data->watchdog_lock);
+ return ret;
+}
+
+static int watchdog_open(struct inode *inode, struct file *filp)
+{
+ struct w83793_data *pos, *data = NULL;
+
+ /* We get called from drivers/char/misc.c with misc_mtx hold, and we
+ call misc_register() from fschmd_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. */
That fschmd_probe should be w83793_probe I think :)
+ 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 */
+ kref_get(&data->kref);
+ mutex_unlock(&watchdog_data_mutex);
+
+ if (test_and_set_bit(0, &data->watchdog_is_open))
+ return -EBUSY;
+
+ /* Enable Soft Watchdog */
+ watchdog_enable(data);
+
+ /* Store pointer to data into filp's private data */
+ filp->private_data = data;
+ return nonseekable_open(inode, filp);
}
+static int watchdog_close(struct inode *inode, struct file *filp)
+{
+ struct w83793_data *data = filp->private_data;
+
+ if (data->watchdog_expect_close) {
+ watchdog_disable(data);
+ data->watchdog_expect_close = 0;
+ } else {
+ watchdog_trigger(data);
+ dev_crit(&data->client->dev,
+ "unexpected close, not stopping watchdog!\n");
+ }
+
+ clear_bit(0, &data->watchdog_is_open);
+
You are missing:
mutex_lock(&watchdog_data_mutex);
kref_put(&data->kref, w83793_release_resources);
mutex_unlock(&watchdog_data_mutex);
Here !!
+ return 0;
+}
+
+static ssize_t watchdog_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *offset)
+{
+ size_t ret;
+ struct w83793_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 < 0)
+ return ret;
+ }
+ return count;
+}
+
+static int watchdog_ioctl(struct inode *inode, struct file *filp,
+ unsigned int cmd, unsigned long arg)
+{
+ static struct watchdog_info ident = {
+ .options = WDIOF_KEEPALIVEPING |
+ WDIOF_SETTIMEOUT |
+ WDIOF_CARDRESET,
+ .identity = "w83793 watchdog"
+ };
+
+ int val, ret = 0;
+ struct w83793_data *data = filp->private_data;
+
+ switch (cmd) {
+ case WDIOC_GETSUPPORT:
+ if (!nowayout)
+ ident.options |= WDIOF_MAGICCLOSE;
+ if (copy_to_user((void __user *)arg, &ident, sizeof(ident)))
+ ret = -EFAULT;
+ break;
+
+ case WDIOC_GETSTATUS:
+ val = data->watchdog_caused_reboot ? WDIOF_CARDRESET : 0;
+ ret = put_user(val, (int __user *)arg);
+ break;
+
+ case WDIOC_GETBOOTSTATUS:
+ ret = put_user(0, (int __user *)arg);
+ break;
+
+ case WDIOC_KEEPALIVE:
+ ret = watchdog_trigger(data);
+ break;
+
+ case WDIOC_GETTIMEOUT:
+ val = watchdog_get_timeout(data);
+ ret = put_user(val, (int __user *)arg);
+ break;
+
+ case WDIOC_SETTIMEOUT:
+ if (get_user(val, (int __user *)arg)) {
+ ret = -EFAULT;
+ break;
+ }
+ ret = watchdog_set_timeout(data, val);
+ if (ret > 0)
+ ret = put_user(ret, (int __user *)arg);
+ break;
+
+ case WDIOC_SETOPTIONS:
+ if (get_user(val, (int __user *)arg)) {
+ ret = -EFAULT;
+ break;
+ }
+
+ if (val & WDIOS_DISABLECARD)
+ ret = watchdog_disable(data);
+ else if (val & WDIOS_ENABLECARD)
+ ret = watchdog_enable(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_close,
+ .write = watchdog_write,
+ .ioctl = watchdog_ioctl,
+};
+
+/*
+ * Notifier for system down
+ */
+
+static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
+ void *unused)
+{
+ struct w83793_data *data = NULL;
+
+ if (code == SYS_DOWN || code == SYS_HALT) {
+
+ /* Disable each registered watchdog */
+ mutex_lock(&watchdog_data_mutex);
+ list_for_each_entry(data, &watchdog_data_list, list) {
+ if (data->watchdog_miscdev.minor)
+ watchdog_disable(data);
+ }
+ mutex_unlock(&watchdog_data_mutex);
+ }
+
+ return NOTIFY_DONE;
+}
+
+/*
+ * The WDT needs to learn about soft shutdowns in order to
+ * turn the timebomb registers off.
+ */
+
+static struct notifier_block watchdog_notifier = {
+ .notifier_call = watchdog_notify_sys,
+};
+
+/*
+ * Init / remove routines
+ */
+
static int w83793_remove(struct i2c_client *client)
{
struct w83793_data *data = i2c_get_clientdata(client);
struct device *dev = &client->dev;
- int i;
+ int i, tmp;
+
+ /* Unregister the watchdog (if registered) */
+ if (data->watchdog_miscdev.minor) {
+ misc_deregister(&data->watchdog_miscdev);
+
+ if (data->watchdog_is_open) {
+ dev_warn(&client->dev,
+ "i2c client detached with watchdog open! "
+ "Stopping watchdog.\n");
+ watchdog_disable(data);
+ }
+
+ mutex_lock(&watchdog_data_mutex);
+ list_del(&data->list);
+ mutex_unlock(&watchdog_data_mutex);
+
+ /* Tell the watchdog code the client is gone */
+ mutex_lock(&data->watchdog_lock);
+ data->client = NULL;
+ mutex_unlock(&data->watchdog_lock);
+ }
+
+ /* Reset Configuration Register to Disable Watch Dog Registers */
+ tmp = w83793_read_value(client, W83793_REG_CONFIG);
+ w83793_write_value(client, W83793_REG_CONFIG, tmp & ~0x04);
+
+ unregister_reboot_notifier(&watchdog_notifier);
hwmon_device_unregister(data->hwmon_dev);
@@ -1102,6 +1495,10 @@ static int w83793_remove(struct i2c_clie
kfree(data);
+ mutex_lock(&watchdog_data_mutex);
+ kref_put(&data->kref, w83793_release_resources);
+ mutex_unlock(&watchdog_data_mutex);
+
return 0;
}
The kfree(data) should be removed, this is done by w83793_release_resources() now.
@@ -1221,6 +1620,7 @@ static int w83793_probe(struct i2c_clien
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
+ const int watchdog_minors[] = { WATCHDOG_MINOR, 212, 213, 214, 215 };
struct w83793_data *data;
int i, tmp, val, err;
int files_fan = ARRAY_SIZE(w83793_left_fan) / 7;
@@ -1236,6 +1638,14 @@ static int w83793_probe(struct i2c_clien
i2c_set_clientdata(client, data);
data->bank = i2c_smbus_read_byte_data(client, W83793_REG_BANKSEL);
mutex_init(&data->update_lock);
+ mutex_init(&data->watchdog_lock);
+ INIT_LIST_HEAD(&data->list);
+ kref_init(&data->kref);
+
+ /* Store client pointer in our data struct for watchdog usage
+ (where the client is found through a data ptr instead of the
+ otherway around) */
+ data->client = client;
err = w83793_detect_subclients(client);
if (err)
@@ -1398,8 +1808,74 @@ static int w83793_probe(struct i2c_clien
goto exit_remove;
}
+ /* Watchdog initialization */
+
+ /* Register boot notifier */
+ err = register_reboot_notifier(&watchdog_notifier);
+ if (err != 0) {
+ dev_err(&client->dev,
+ "cannot register reboot notifier (err=%d)\n", err);
+ goto exit_devunreg;
+ }
+
+ /* Enable Watchdog registers.
+ Set Configuration Register to Enable Watch Dog Registers
+ (Bit 2) = XXXX, X1XX. */
+ tmp = w83793_read_value(client, W83793_REG_CONFIG);
+ w83793_write_value(client, W83793_REG_CONFIG, tmp | 0x04);
+
+ /* Check, if last reboot was caused by watchdog */
+ data->watchdog_caused_reboot =
+ w83793_read_value(data->client, W83793_REG_WDT_STATUS) & 0x01;
+
+ /* Disable Soft Watchdog during initialiation */
+ watchdog_disable(data);
+
+ /* 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 (and set the default timeout) */
+ 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) {
+ data->watchdog_miscdev.minor = 0;
+ dev_err(&client->dev,
+ "Registering watchdog chardev: %d\n", err);
+ break;
+ }
+
+ list_add(&data->list, &watchdog_data_list);
+
+ dev_info(&client->dev,
+ "Registered watchdog chardev major 10, minor: %d\n",
+ watchdog_minors[i]);
+ break;
+ }
+ if (i == ARRAY_SIZE(watchdog_minors)) {
+ data->watchdog_miscdev.minor = 0;
+ dev_warn(&client->dev, "Couldn't register watchdog chardev "
+ "(due to no free minor)\n");
+ }
+
+ mutex_unlock(&watchdog_data_mutex);
+
You do not seem to be setting a default timeout here even though you've made this configurable
through a module parameter, but this might be due to the remarks given above wrt the trigger.
return 0;
+ /* Unregister hwmon device */
+
+exit_devunreg:
+
+ hwmon_device_unregister(data->hwmon_dev);
+
/* Unregister sysfs hooks */
exit_remove:
@@ -1646,7 +2124,7 @@ static void __exit sensors_w83793_exit(v
i2c_del_driver(&w83793_driver);
}
-MODULE_AUTHOR("Yuan Mu");
+MODULE_AUTHOR("Yuan Mu, Rudolf Marek, Sven Anders");
MODULE_DESCRIPTION("w83793 driver");
MODULE_LICENSE("GPL");
Not quite sure why you are adding Rudolf Marek here.
--- linux-2.6.29.6/drivers/hwmon/Kconfig 2009-07-03 01:41:20.000000000 +0200
+++ linux-2.6.29.6.watchdog/drivers/hwmon/Kconfig 2009-12-04 12:13:08.000000000 +0100
@@ -789,7 +789,8 @@ config SENSORS_W83793
select HWMON_VID
help
If you say yes here you get support for the Winbond W83793
- hardware monitoring chip.
+ hardware monitoring chip, including support for the integrated
+ watchdog.
This driver can also be built as a module. If so, the module
will be called w83793.
Regards,
Hans
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