On 21/08/2015:08:19:03 AM, Guenter Roeck wrote: > On Fri, Aug 21, 2015 at 02:22:17PM +0530, Pratyush Anand wrote: > > On 18/08/2015:07:23:38 AM, Guenter Roeck wrote: > > > Sounds good. We should have a 'name' attribute as well. We'll also need > > > 'timeout', 'keepalive' to ping the watchdog, 'timeleft', and 'bootstatus'. > > > Not sure what else. > > > > > > The attributes should be implemented as class attributes, to ensure > > > that they are created and removed automatically. That may require > > > the watchdog class to be static instead of a pointer. > > > > Should n't attributes be implemented as device attribute as they are properties > > of each device. Under the class watchdog_class, we can have multiple device on a > > system, and these attributes would be different for different devices. So, what > > I am thinking is to create device in __watchdog_register_device using > > device_create_with_groups instead of device_create. Here we can link a > > attribute_group with all attributes you suggested. > > > Class attibutes are created automatically for each device registered which is > a member of the class. They are attached to the device, not to the class. Not sure, if we both are referring to same thing.. So, I did a basic testing. I changed "static struct class *watchdog_class;" to "tatic struct class watchdog_class" and other than .name and .owner I added .class_attrs and then further added one node "state" in this class_attrs. I have two watchdog in my system, so I was expecting /sys/class/watchdog/watchdog0/state and /sys/class/watchdog/watchdog1/state. But I see that there is only /sys/class/watchdog/state with the above approach. > In other words, the infrastructure creates the attributes, the driver doesn't > have to do it, and there is no race condition where the device exists but > the attributes are not yet there. Yes, I agree that individual driver does not need to do anything. watchdog_core.c and watchdog_dev.c will take care for each of the device registered with it. I am able to do that, but not using .class_attrs, rather using device_create_with_groups. > > Not sure what you mean with "different". Can you elaborate ? As I said above, with the "different" I meant that we should have state in each /sys/class/watchdog/watchdogn. ~Pratyush -- To unsubscribe from this list: send the line "unsubscribe linux-watchdog" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
