[PATCHv8 01/10] watchdog: Rename watchdog_active to watchdog_hw_active

Timo Kokkonen timo.kokkonen at offcode.fi
Tue May 19 22:37:35 PDT 2015


On 20.05.2015 04:10, Guenter Roeck wrote:
> On 05/19/2015 01:26 AM, Timo Kokkonen wrote:
>> Before extending the watchdog core midlayer, it is useful to rename
>> the watchdog_active function so that it states explicitly what it
>> really does. That is, "active" watchdog means really that the watchdog
>> hardware is running and needs pinging to prevent a watchdog reset
>> taking place in near future.
>>
>> This is different to "watchdog open" state, which simply states that
>> kernel is expecting the user space to keep the watchdog alive. These
>> states might become different mainly because some hardware have
>> limitations that prevent them from being stopped at will.
>>
>
> I don't see why this is needed. If you need another state, per your
> description, it would be "open" in addition to "active".

Yes, the watchdog_is_open() is introduced on patch number two. The 
original watchdog_is_active() is really confusing. It doesn't really 
state what it means. Most of the drivers are using it to test whether 
the watchdog HW is active when going to suspend, but at least atmel 
watchdog was testing it to see whether the watchdog device is open from 
user space. The HW itself is always active in that driver.

If we are about to distinguish between "device open from user space" and 
"hardware timer running", we better be clear about the naming. 
"watchdog_is_active" doesn't really tell what it does.

This was originally suggested by Uwe Kleine-König. He also recommended 
changing the timeout parameter so that is would state more clearly that 
it is the SW timeout and not HW timeout. But I felt that it would have 
been too invasive to change the timeout parameter as well. The 
watchdog_is_active was not used very much so the change was easy.

-Timo



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