[PATCH v2] rtc: rtc-ds1374: wdt: Use watchdog core for watchdog part
From: Johnson CH Chen (陳昭勳)
Date: Fri Jul 03 2020 - 07:48:20 EST
Let ds1374 watchdog use watchdog core functions. It also includes
improving watchdog timer setting and nowayout, and just uses ioctl()
of watchdog core.
Signed-off-by: Johnson Chen <johnsonch.chen@xxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
v1->v2:
- Use ds1374_wdt_settimeout() before registering the watchdog
- Remove watchdog_unregister_device() because devm_watchdog_register_device() is used
- Remove ds1374_wdt_ping()
- TIMER_MARGIN_MAX to 4095 for 24-bit value
- Keep wdt_margin
- Fix coding styles
---
drivers/rtc/Kconfig | 1 +
drivers/rtc/rtc-ds1374.c | 236 +++++++++------------------------------
2 files changed, 52 insertions(+), 185 deletions(-)
diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index b54d87d45c89..5e2444af5657 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -282,6 +282,7 @@ config RTC_DRV_DS1374
config RTC_DRV_DS1374_WDT
bool "Dallas/Maxim DS1374 watchdog timer"
depends on RTC_DRV_DS1374
+ select WATCHDOG_CORE
help
If you say Y here you will get support for the
watchdog timer in the Dallas Semiconductor DS1374
diff --git a/drivers/rtc/rtc-ds1374.c b/drivers/rtc/rtc-ds1374.c
index 9c51a12cf70f..57a4e503b34a 100644
--- a/drivers/rtc/rtc-ds1374.c
+++ b/drivers/rtc/rtc-ds1374.c
@@ -46,6 +46,7 @@
#define DS1374_REG_WDALM2 0x06
#define DS1374_REG_CR 0x07 /* Control */
#define DS1374_REG_CR_AIE 0x01 /* Alarm Int. Enable */
+#define DS1374_REG_CR_WDSTR 0x08 /* 1=INT, 0=RST */
#define DS1374_REG_CR_WDALM 0x20 /* 1=Watchdog, 0=Alarm */
#define DS1374_REG_CR_WACE 0x40 /* WD/Alarm counter enable */
#define DS1374_REG_SR 0x08 /* Status */
@@ -71,7 +72,9 @@ struct ds1374 {
struct i2c_client *client;
struct rtc_device *rtc;
struct work_struct work;
-
+#ifdef CONFIG_RTC_DRV_DS1374_WDT
+ struct watchdog_device wdt;
+#endif
/* The mutex protects alarm operations, and prevents a race
* between the enable_irq() in the workqueue and the free_irq()
* in the remove function.
@@ -371,72 +374,76 @@ static const struct rtc_class_ops ds1374_rtc_ops = {
*/
static struct i2c_client *save_client;
/* Default margin */
-#define WD_TIMO 131762
+#define TIMER_MARGIN_DEFAULT 32
+#define TIMER_MARGIN_MIN 1
+#define TIMER_MARGIN_MAX 4095 /* 24-bit value */
#define DRV_NAME "DS1374 Watchdog"
-static int wdt_margin = WD_TIMO;
-static unsigned long wdt_is_open;
+static int wdt_margin = TIMER_MARGIN_DEFAULT;
module_param(wdt_margin, int, 0);
MODULE_PARM_DESC(wdt_margin, "Watchdog timeout in seconds (default 32s)");
+static bool nowayout = WATCHDOG_NOWAYOUT;
+module_param(nowayout, bool, 0);
+MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default ="
+ __MODULE_STRING(WATCHDOG_NOWAYOUT)")");
+
+
static const struct watchdog_info ds1374_wdt_info = {
.identity = "DS1374 WTD",
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING |
WDIOF_MAGICCLOSE,
};
-static int ds1374_wdt_settimeout(unsigned int timeout)
+static int ds1374_wdt_settimeout(struct watchdog_device *wdt, unsigned int timeout)
{
- int ret = -ENOIOCTLCMD;
- int cr;
+ int ret, cr;
- ret = cr = i2c_smbus_read_byte_data(save_client, DS1374_REG_CR);
- if (ret < 0)
- goto out;
+ wdt->timeout = timeout;
+
+ cr = i2c_smbus_read_byte_data(save_client, DS1374_REG_CR);
+ if (cr < 0)
+ return cr;
/* Disable any existing watchdog/alarm before setting the new one */
cr &= ~DS1374_REG_CR_WACE;
ret = i2c_smbus_write_byte_data(save_client, DS1374_REG_CR, cr);
if (ret < 0)
- goto out;
+ return ret;
/* Set new watchdog time */
+ timeout = timeout * 4096;
ret = ds1374_write_rtc(save_client, timeout, DS1374_REG_WDALM0, 3);
if (ret) {
pr_info("couldn't set new watchdog time\n");
- goto out;
+ return ret;
}
/* Enable watchdog timer */
cr |= DS1374_REG_CR_WACE | DS1374_REG_CR_WDALM;
+ cr &= ~DS1374_REG_CR_WDSTR;/* for RST PIN */
cr &= ~DS1374_REG_CR_AIE;
ret = i2c_smbus_write_byte_data(save_client, DS1374_REG_CR, cr);
if (ret < 0)
- goto out;
+ return ret;
return 0;
-out:
- return ret;
}
-
/*
* Reload the watchdog timer. (ie, pat the watchdog)
*/
-static void ds1374_wdt_ping(void)
+static int ds1374_wdt_start(struct watchdog_device *wdt)
{
u32 val;
- int ret = 0;
- ret = ds1374_read_rtc(save_client, &val, DS1374_REG_WDALM0, 3);
- if (ret)
- pr_info("WD TICK FAIL!!!!!!!!!! %i\n", ret);
+ return ds1374_read_rtc(save_client, &val, DS1374_REG_WDALM0, 3);
}
-static void ds1374_wdt_disable(void)
+static int ds1374_wdt_stop(struct watchdog_device *wdt)
{
int cr;
@@ -444,162 +451,16 @@ static void ds1374_wdt_disable(void)
/* Disable watchdog timer */
cr &= ~DS1374_REG_CR_WACE;
- i2c_smbus_write_byte_data(save_client, DS1374_REG_CR, cr);
-}
-
-/*
- * Watchdog device is opened, and watchdog starts running.
- */
-static int ds1374_wdt_open(struct inode *inode, struct file *file)
-{
- struct ds1374 *ds1374 = i2c_get_clientdata(save_client);
-
- if (MINOR(inode->i_rdev) == WATCHDOG_MINOR) {
- mutex_lock(&ds1374->mutex);
- if (test_and_set_bit(0, &wdt_is_open)) {
- mutex_unlock(&ds1374->mutex);
- return -EBUSY;
- }
- /*
- * Activate
- */
- wdt_is_open = 1;
- mutex_unlock(&ds1374->mutex);
- return stream_open(inode, file);
- }
- return -ENODEV;
-}
-
-/*
- * Close the watchdog device.
- */
-static int ds1374_wdt_release(struct inode *inode, struct file *file)
-{
- if (MINOR(inode->i_rdev) == WATCHDOG_MINOR)
- clear_bit(0, &wdt_is_open);
-
- return 0;
+ return i2c_smbus_write_byte_data(save_client, DS1374_REG_CR, cr);
}
-/*
- * Pat the watchdog whenever device is written to.
- */
-static ssize_t ds1374_wdt_write(struct file *file, const char __user *data,
- size_t len, loff_t *ppos)
-{
- if (len) {
- ds1374_wdt_ping();
- return 1;
- }
- return 0;
-}
-
-static ssize_t ds1374_wdt_read(struct file *file, char __user *data,
- size_t len, loff_t *ppos)
-{
- return 0;
-}
-
-/*
- * Handle commands from user-space.
- */
-static long ds1374_wdt_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- int new_margin, options;
-
- switch (cmd) {
- case WDIOC_GETSUPPORT:
- return copy_to_user((struct watchdog_info __user *)arg,
- &ds1374_wdt_info, sizeof(ds1374_wdt_info)) ? -EFAULT : 0;
-
- case WDIOC_GETSTATUS:
- case WDIOC_GETBOOTSTATUS:
- return put_user(0, (int __user *)arg);
- case WDIOC_KEEPALIVE:
- ds1374_wdt_ping();
- return 0;
- case WDIOC_SETTIMEOUT:
- if (get_user(new_margin, (int __user *)arg))
- return -EFAULT;
-
- /* the hardware's tick rate is 4096 Hz, so
- * the counter value needs to be scaled accordingly
- */
- new_margin <<= 12;
- if (new_margin < 1 || new_margin > 16777216)
- return -EINVAL;
-
- wdt_margin = new_margin;
- ds1374_wdt_settimeout(new_margin);
- ds1374_wdt_ping();
- /* fallthrough */
- case WDIOC_GETTIMEOUT:
- /* when returning ... inverse is true */
- return put_user((wdt_margin >> 12), (int __user *)arg);
- case WDIOC_SETOPTIONS:
- if (copy_from_user(&options, (int __user *)arg, sizeof(int)))
- return -EFAULT;
-
- if (options & WDIOS_DISABLECARD) {
- pr_info("disable watchdog\n");
- ds1374_wdt_disable();
- return 0;
- }
-
- if (options & WDIOS_ENABLECARD) {
- pr_info("enable watchdog\n");
- ds1374_wdt_settimeout(wdt_margin);
- ds1374_wdt_ping();
- return 0;
- }
- return -EINVAL;
- }
- return -ENOTTY;
-}
-
-static long ds1374_wdt_unlocked_ioctl(struct file *file, unsigned int cmd,
- unsigned long arg)
-{
- int ret;
- struct ds1374 *ds1374 = i2c_get_clientdata(save_client);
-
- mutex_lock(&ds1374->mutex);
- ret = ds1374_wdt_ioctl(file, cmd, arg);
- mutex_unlock(&ds1374->mutex);
-
- return ret;
-}
-
-static int ds1374_wdt_notify_sys(struct notifier_block *this,
- unsigned long code, void *unused)
-{
- if (code == SYS_DOWN || code == SYS_HALT)
- /* Disable Watchdog */
- ds1374_wdt_disable();
- return NOTIFY_DONE;
-}
-
-static const struct file_operations ds1374_wdt_fops = {
- .owner = THIS_MODULE,
- .read = ds1374_wdt_read,
- .unlocked_ioctl = ds1374_wdt_unlocked_ioctl,
- .compat_ioctl = compat_ptr_ioctl,
- .write = ds1374_wdt_write,
- .open = ds1374_wdt_open,
- .release = ds1374_wdt_release,
- .llseek = no_llseek,
+static const struct watchdog_ops ds1374_wdt_ops = {
+ .owner = THIS_MODULE,
+ .start = ds1374_wdt_start,
+ .stop = ds1374_wdt_stop,
+ .set_timeout = ds1374_wdt_settimeout,
};
-static struct miscdevice ds1374_miscdev = {
- .minor = WATCHDOG_MINOR,
- .name = "watchdog",
- .fops = &ds1374_wdt_fops,
-};
-
-static struct notifier_block ds1374_wdt_notifier = {
- .notifier_call = ds1374_wdt_notify_sys,
-};
#endif /*CONFIG_RTC_DRV_DS1374_WDT*/
/*
@@ -653,15 +514,25 @@ static int ds1374_probe(struct i2c_client *client,
#ifdef CONFIG_RTC_DRV_DS1374_WDT
save_client = client;
- ret = misc_register(&ds1374_miscdev);
- if (ret)
- return ret;
- ret = register_reboot_notifier(&ds1374_wdt_notifier);
+ ds1374->wdt.info = &ds1374_wdt_info;
+ ds1374->wdt.ops = &ds1374_wdt_ops;
+ ds1374->wdt.timeout = TIMER_MARGIN_DEFAULT;
+ ds1374->wdt.min_timeout = TIMER_MARGIN_MIN;
+ ds1374->wdt.max_timeout = TIMER_MARGIN_MAX;
+
+ watchdog_init_timeout(&ds1374->wdt, wdt_margin, &client->dev);
+ watchdog_set_nowayout(&ds1374->wdt, nowayout);
+ watchdog_stop_on_reboot(&ds1374->wdt);
+ watchdog_stop_on_unregister(&ds1374->wdt);
+ ds1374_wdt_settimeout(&ds1374->wdt, wdt_margin);
+
+ ret = devm_watchdog_register_device(&client->dev, &ds1374->wdt);
if (ret) {
- misc_deregister(&ds1374_miscdev);
+ dev_err(&client->dev, "failed to register DS1374 watchdog device\n");
return ret;
}
- ds1374_wdt_settimeout(131072);
+
+ dev_info(&client->dev, "DS1374 watchdog device enabled\n");
#endif
return 0;
@@ -670,11 +541,6 @@ static int ds1374_probe(struct i2c_client *client,
static int ds1374_remove(struct i2c_client *client)
{
struct ds1374 *ds1374 = i2c_get_clientdata(client);
-#ifdef CONFIG_RTC_DRV_DS1374_WDT
- misc_deregister(&ds1374_miscdev);
- ds1374_miscdev.parent = NULL;
- unregister_reboot_notifier(&ds1374_wdt_notifier);
-#endif
if (client->irq > 0) {
mutex_lock(&ds1374->mutex);
--
2.20.1