[PATCH v2] rtc: rtc-ds1374: wdt: Use watchdog core for watchdog part

[PATCH v2] rtc: rtc-ds1374: wdt: Use watchdog core for watchdog part

[Johnson CH Chen (陳昭勳)]

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@moxa.com>
Reported-by: kernel test robot <lkp@intel.com>

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

Re: [PATCH v2] rtc: rtc-ds1374: wdt: Use watchdog core for watchdog part

[kernel test robot]

[-- Attachment #1: Type: text/plain, Size: 1985 bytes --]

Hi "Johnson,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on abelloni/rtc-next]
[also build test ERROR on linux/master linus/master v5.8-rc3 next-20200703]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use  as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Johnson-CH-Chen/rtc-rtc-ds1374-wdt-Use-watchdog-core-for-watchdog-part/20200703-195053
base:   https://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux.git rtc-next
config: openrisc-randconfig-c004-20200701 (attached as .config)
compiler: or1k-linux-gcc (GCC) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   or1k-linux-ld: drivers/rtc/rtc-ds1307.o: in function `ds1307_probe':
   rtc-ds1307.c:(.text+0x2a88): undefined reference to `watchdog_init_timeout'
   rtc-ds1307.c:(.text+0x2a88): relocation truncated to fit: R_OR1K_INSN_REL_26 against undefined symbol `watchdog_init_timeout'
>> or1k-linux-ld: rtc-ds1307.c:(.text+0x2a98): undefined reference to `devm_watchdog_register_device'
   rtc-ds1307.c:(.text+0x2a98): relocation truncated to fit: R_OR1K_INSN_REL_26 against undefined symbol `devm_watchdog_register_device'
   or1k-linux-ld: drivers/rtc/rtc-ds1374.o: in function `ds1374_probe':
   rtc-ds1374.c:(.text+0xa5c): undefined reference to `watchdog_init_timeout'
   rtc-ds1374.c:(.text+0xa5c): relocation truncated to fit: R_OR1K_INSN_REL_26 against undefined symbol `watchdog_init_timeout'
>> or1k-linux-ld: rtc-ds1374.c:(.text+0xac8): undefined reference to `devm_watchdog_register_device'
   rtc-ds1374.c:(.text+0xac8): relocation truncated to fit: R_OR1K_INSN_REL_26 against undefined symbol `devm_watchdog_register_device'

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org

[-- Attachment #2: .config.gz --]
[-- Type: application/gzip, Size: 41279 bytes --]

Re: [PATCH v2] rtc: rtc-ds1374: wdt: Use watchdog core for watchdog part

[Guenter Roeck]

On Fri, Jul 03, 2020 at 11:48:09AM +0000, Johnson CH Chen (陳昭勳) wrote:
> 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@moxa.com>
> Reported-by: kernel test robot <lkp@intel.com>
> 
> 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

This has to be

	select WATCHDOG_CORE if WATCHDOG

to fix the problem reported by 0-day.

>  	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;

This is no longer necessary. struct watchdog_device is part of struct ds1374,
so it is possible to derive the pointer to struct ds1374 from it and get the
client pointer from there.

>  /* 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;

Should be 0, not 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");

dev_info() can now be used since we have a device. _info seems to be wrong,
though, since this is an error.

> -		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");

Is that necessary ?

>  #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

RE: [PATCH v2] rtc: rtc-ds1374: wdt: Use watchdog core for watchdog part

[Johnson CH Chen (陳昭勳)]

Hi,

Thanks for your good suggestions!

> > 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
> 
> This has to be
> 
> 	select WATCHDOG_CORE if WATCHDOG
> 
> to fix the problem reported by 0-day.
> 
> >  	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;
> 
> This is no longer necessary. struct watchdog_device is part of struct ds1374, so
> it is possible to derive the pointer to struct ds1374 from it and get the client
> pointer from there.
> 
> >  /* 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;
> 
> Should be 0, not 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");
> 
> dev_info() can now be used since we have a device. _info seems to be wrong,
> though, since this is an error.
> 
> > -		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");
> 
> Is that necessary ?
> 

I think it's good to show watchdog initial timeout. I'll include above suggestions in v3, thanks!

Best regards,
Johnson
> >  #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

Re: [PATCH v2] rtc: rtc-ds1374: wdt: Use watchdog core for watchdog part

[Alexandre Belloni]

On 06/07/2020 05:18:39+0000, Johnson CH Chen (陳昭勳) wrote:
> > >  #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");

There was no error message before, I don't think this one is necessary.

> > >  		return ret;
> > >  	}
> > > -	ds1374_wdt_settimeout(131072);
> > > +
> > > +	dev_info(&client->dev, "DS1374 watchdog device enabled\n");
> > 
> > Is that necessary ?
> > 
> 
> I think it's good to show watchdog initial timeout. I'll include above suggestions in v3, thanks!
> 

No, please avoid adding more strings in that driver.


-- 
Alexandre Belloni, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

RE: [PATCH v2] rtc: rtc-ds1374: wdt: Use watchdog core for watchdog part

[Johnson CH Chen (陳昭勳)]

Hi,

> > > > +	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");
> 
> There was no error message before, I don't think this one is necessary.
> 
> > > >  		return ret;
> > > >  	}
> > > > -	ds1374_wdt_settimeout(131072);
> > > > +
> > > > +	dev_info(&client->dev, "DS1374 watchdog device enabled\n");
> > >
> > > Is that necessary ?
> > >
> >
> > I think it's good to show watchdog initial timeout. I'll include above
> suggestions in v3, thanks!
> >
> 
> No, please avoid adding more strings in that driver.
> 

I get it, thanks for review!

Best regards,
Johnson
> 
> --
> Alexandre Belloni, Bootlin
> Embedded Linux and Kernel engineering
> https://bootlin.com