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watchdog: sch56xx: Use watchdog core

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Convert sch56xx drivers to the generic watchdog core.

Note this patch depends on the "watchdog: Add multiple device support" patch
from Alan Cox.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This commit is contained in:
Hans de Goede 2012-05-22 11:40:24 +02:00 committed by Wim Van Sebroeck
parent e907df3272
commit fb551405c0
4 changed files with 61 additions and 316 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/hwmon/sch5627.c
View File

@ -579,7 +579,7 @@ static int __devinit sch5627_probe(struct platform_device *pdev)
} }
/* Note failing to register the watchdog is not a fatal error */ /* Note failing to register the watchdog is not a fatal error */
data->watchdog = sch56xx_watchdog_register(data->addr, data->watchdog = sch56xx_watchdog_register(&pdev->dev, data->addr,
(build_code << 24) | (build_id << 8) | hwmon_rev, (build_code << 24) | (build_id << 8) | hwmon_rev,
&data->update_lock, 1); &data->update_lock, 1);

2
drivers/hwmon/sch5636.c
View File

@ -510,7 +510,7 @@ static int __devinit sch5636_probe(struct platform_device *pdev)
} }
/* Note failing to register the watchdog is not a fatal error */ /* Note failing to register the watchdog is not a fatal error */
data->watchdog = sch56xx_watchdog_register(data->addr, data->watchdog = sch56xx_watchdog_register(&pdev->dev, data->addr,
(revision[0] << 8) | revision[1], (revision[0] << 8) | revision[1],
&data->update_lock, 0); &data->update_lock, 0);

371
drivers/hwmon/sch56xx-common.c
View File

@ -66,15 +66,9 @@ MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
struct sch56xx_watchdog_data { struct sch56xx_watchdog_data {
u16 addr; u16 addr;
u32 revision;
struct mutex *io_lock; struct mutex *io_lock;
struct mutex watchdog_lock; struct watchdog_info wdinfo;
struct list_head list; /* member of the watchdog_data_list */ struct watchdog_device wddev;
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;
u8 watchdog_preset; u8 watchdog_preset;
u8 watchdog_control; u8 watchdog_control;
u8 watchdog_output_enable; u8 watchdog_output_enable;
@ -82,15 +76,6 @@ struct sch56xx_watchdog_data {
static struct platform_device *sch56xx_pdev; 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 */ /* Super I/O functions */
static inline int superio_inb(int base, int reg) static inline int superio_inb(int base, int reg)
{ {
@ -272,22 +257,13 @@ EXPORT_SYMBOL(sch56xx_read_virtual_reg12);
* Watchdog routines * Watchdog routines
*/ */
/* static int watchdog_set_timeout(struct watchdog_device *wddev,
* Release our data struct when the platform device has been released *and* unsigned int timeout)
* all references to our watchdog device are released.
*/
static void sch56xx_watchdog_release_resources(struct kref *r)
{ {
struct sch56xx_watchdog_data *data = struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
container_of(r, struct sch56xx_watchdog_data, kref); unsigned int resolution;
kfree(data);
}
static int watchdog_set_timeout(struct sch56xx_watchdog_data *data,
int timeout)
{
int ret, resolution;
u8 control; u8 control;
int ret;
/* 1 second or 60 second resolution? */ /* 1 second or 60 second resolution? */
if (timeout <= 255) if (timeout <= 255)
@ -298,12 +274,6 @@ static int watchdog_set_timeout(struct sch56xx_watchdog_data *data,
if (timeout < resolution || timeout > (resolution * 255)) if (timeout < resolution || timeout > (resolution * 255))
return -EINVAL; return -EINVAL;
mutex_lock(&data->watchdog_lock);
if (!data->addr) {
ret = -ENODEV;
goto leave;
}
if (resolution == 1) if (resolution == 1)
control = data->watchdog_control | SCH56XX_WDOG_TIME_BASE_SEC; control = data->watchdog_control | SCH56XX_WDOG_TIME_BASE_SEC;
else else
@ -316,7 +286,7 @@ static int watchdog_set_timeout(struct sch56xx_watchdog_data *data,
control); control);
mutex_unlock(data->io_lock); mutex_unlock(data->io_lock);
if (ret) if (ret)
goto leave; return ret;
data->watchdog_control = control; data->watchdog_control = control;
} }
@ -326,38 +296,17 @@ static int watchdog_set_timeout(struct sch56xx_watchdog_data *data,
* the watchdog countdown. * the watchdog countdown.
*/ */
data->watchdog_preset = DIV_ROUND_UP(timeout, resolution); data->watchdog_preset = DIV_ROUND_UP(timeout, resolution);
wddev->timeout = data->watchdog_preset * resolution;
ret = data->watchdog_preset * resolution; return 0;
leave:
mutex_unlock(&data->watchdog_lock);
return ret;
} }
static int watchdog_get_timeout(struct sch56xx_watchdog_data *data) static int watchdog_start(struct watchdog_device *wddev)
{
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;
}
static int watchdog_start(struct sch56xx_watchdog_data *data)
{ {
struct sch56xx_watchdog_data *data = watchdog_get_drvdata(wddev);
int ret; int ret;
u8 val; 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 * The sch56xx's watchdog cannot really be started / stopped
* it is always running, but we can avoid the timer expiring * it is always running, but we can avoid the timer expiring
@ -405,39 +354,29 @@ static int watchdog_start(struct sch56xx_watchdog_data *data)
leave: leave:
mutex_unlock(data->io_lock); mutex_unlock(data->io_lock);
leave_unlock_watchdog:
mutex_unlock(&data->watchdog_lock);
return ret; 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; int ret;
mutex_lock(&data->watchdog_lock);
if (!data->addr) {
ret = -ENODEV;
goto leave;
}
/* Reset the watchdog countdown counter */ /* Reset the watchdog countdown counter */
mutex_lock(data->io_lock); mutex_lock(data->io_lock);
ret = sch56xx_write_virtual_reg(data->addr, SCH56XX_REG_WDOG_PRESET, ret = sch56xx_write_virtual_reg(data->addr, SCH56XX_REG_WDOG_PRESET,
data->watchdog_preset); data->watchdog_preset);
mutex_unlock(data->io_lock); mutex_unlock(data->io_lock);
leave:
mutex_unlock(&data->watchdog_lock);
return ret; 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; int ret = 0;
u8 val; u8 val;
if (!data->addr)
return -ENODEV;
if (data->watchdog_output_enable & SCH56XX_WDOG_OUTPUT_ENABLE) { if (data->watchdog_output_enable & SCH56XX_WDOG_OUTPUT_ENABLE) {
val = data->watchdog_output_enable & val = data->watchdog_output_enable &
~SCH56XX_WDOG_OUTPUT_ENABLE; ~SCH56XX_WDOG_OUTPUT_ENABLE;
@ -455,184 +394,19 @@ static int watchdog_stop_unlocked(struct sch56xx_watchdog_data *data)
return ret; return ret;
} }
static int watchdog_stop(struct sch56xx_watchdog_data *data) static const struct watchdog_ops watchdog_ops = {
{ .owner = THIS_MODULE,
int ret; .start = watchdog_start,
.stop = watchdog_stop,
mutex_lock(&data->watchdog_lock); .ping = watchdog_trigger,
ret = watchdog_stop_unlocked(data); .set_timeout = watchdog_set_timeout,
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,
}; };
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) u16 addr, u32 revision, struct mutex *io_lock, int check_enabled)
{ {
struct sch56xx_watchdog_data *data; struct sch56xx_watchdog_data *data;
int i, err, control, output_enable; int err, control, output_enable;
const int watchdog_minors[] = { WATCHDOG_MINOR, 212, 213, 214, 215 };
/* Cache the watchdog registers */ /* Cache the watchdog registers */
mutex_lock(io_lock); mutex_lock(io_lock);
@ -656,82 +430,53 @@ struct sch56xx_watchdog_data *sch56xx_watchdog_register(
return NULL; return NULL;
data->addr = addr; data->addr = addr;
data->revision = revision;
data->io_lock = io_lock; data->io_lock = io_lock;
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 */
data->watchdog_control = control; data->watchdog_control = control;
data->watchdog_output_enable = output_enable; 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;
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);
watchdog_set_drvdata(&data->wddev, data);
err = watchdog_register_device(&data->wddev);
if (err) { if (err) {
pr_err("Registering watchdog chardev: %d\n", err); pr_err("Registering watchdog chardev: %d\n", err);
goto error; kfree(data);
} return NULL;
if (i == ARRAY_SIZE(watchdog_minors)) {
pr_warn("Couldn't register watchdog (no free minor)\n");
goto error;
} }
return data; return data;
error:
kfree(data);
return NULL;
} }
EXPORT_SYMBOL(sch56xx_watchdog_register); EXPORT_SYMBOL(sch56xx_watchdog_register);
void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data) void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data)
{ {
mutex_lock(&watchdog_data_mutex); watchdog_unregister_device(&data->wddev);
misc_deregister(&data->watchdog_miscdev); kfree(data);
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);
} }
EXPORT_SYMBOL(sch56xx_watchdog_unregister); EXPORT_SYMBOL(sch56xx_watchdog_unregister);

2
drivers/hwmon/sch56xx-common.h
View File

@ -27,6 +27,6 @@ int sch56xx_read_virtual_reg16(u16 addr, u16 reg);
int sch56xx_read_virtual_reg12(u16 addr, u16 msb_reg, u16 lsn_reg, int sch56xx_read_virtual_reg12(u16 addr, u16 msb_reg, u16 lsn_reg,
int high_nibble); int high_nibble);
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); u16 addr, u32 revision, struct mutex *io_lock, int check_enabled);
void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data); void sch56xx_watchdog_unregister(struct sch56xx_watchdog_data *data);