Re: [PATCH v2] watchdog: Add {min,max}_timeout sysfs nodes

[Guenter Roeck]

On 5/10/21 11:29 PM, Juerg Haefliger wrote:
> The valid range for the 'timeout' value is useful information so expose
> the min and max timeout values via sysfs.
>
> Signed-off-by: Juerg Haefliger <juergh@xxxxxxxxxxxxx>

Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx>

> ---
>
> v1->v2:
>   - replace sprintf() with sysfs_emit().
>
>   drivers/watchdog/watchdog_dev.c | 20 ++++++++++++++++++++
>   1 file changed, 20 insertions(+)
>
> diff --git a/drivers/watchdog/watchdog_dev.c b/drivers/watchdog/watchdog_dev.c
> index fe68a97973a5..7c1007ab1b71 100644
> --- a/drivers/watchdog/watchdog_dev.c
> +++ b/drivers/watchdog/watchdog_dev.c
> @@ -526,6 +526,24 @@ static ssize_t timeout_show(struct device *dev, struct device_attribute *attr,
>   }
>   static DEVICE_ATTR_RO(timeout);
>   
> +static ssize_t min_timeout_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct watchdog_device *wdd = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%u\n", wdd->min_timeout);
> +}
> +static DEVICE_ATTR_RO(min_timeout);
> +
> +static ssize_t max_timeout_show(struct device *dev,
> +				struct device_attribute *attr, char *buf)
> +{
> +	struct watchdog_device *wdd = dev_get_drvdata(dev);
> +
> +	return sysfs_emit(buf, "%u\n", wdd->max_timeout);
> +}
> +static DEVICE_ATTR_RO(max_timeout);
> +
>   static ssize_t pretimeout_show(struct device *dev,
>   			       struct device_attribute *attr, char *buf)
>   {
> @@ -610,6 +628,8 @@ static struct attribute *wdt_attrs[] = {
>   	&dev_attr_state.attr,
>   	&dev_attr_identity.attr,
>   	&dev_attr_timeout.attr,
> +	&dev_attr_min_timeout.attr,
> +	&dev_attr_max_timeout.attr,
>   	&dev_attr_pretimeout.attr,
>   	&dev_attr_timeleft.attr,
>   	&dev_attr_bootstatus.attr,