Re: [PATCH v5] watchdog: add driver for StreamLabs USB watchdog device

From: Oliver Neukum
Date: Mon Aug 01 2022 - 05:47:31 EST




On 31.07.22 04:34, Alexey Klimov wrote:
> On Tue, Jul 26, 2022 at 8:48 AM Oliver Neukum <oneukum@xxxxxxxx> wrote:

> You're right. Upon reset the watchdog is disabled even if it was active before.
> Adding empty ->pre_reset() and ->post_reset() helps to avoid that, but
> looking at Documentation and other drivers it seems that I need to do:
> in pre_reset():
> mutex_lock() to block any other I/O to the usb device;
> __usb_streamlabs_wdt_cmd(STOP) to stop the watchdog;
> and do not unlock the mutex;
>
> in post_reset():
> if (watchdog_active())
> __usb_streamlabs_wdt_cmd(START);
> mutex_unlock() to allow other's I/O to the usb deivce.
>
> Seems right?

Hi,

I suppose if you make reenabling the watchdog conditional,
you may just as well do the same for disabling it.

Regards
Oliver