Re: [PATCH] gpiolib: suppress error message on EPROBE_DEFER

From: Grygorii Strashko
Date: Thu Feb 08 2018 - 13:19:28 EST




On 02/07/2018 06:57 AM, Linus Walleij wrote:
> On Sun, Jan 21, 2018 at 9:32 PM, David Lechner <david@xxxxxxxxxxxxxx> wrote:
>
>> This suppresses printing an error message during probe of gpio drivers
>> when the error is EPROBE_DEFER.
>>
>> Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
>> Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx>
>
> I'm not sure about this.
>
> GPIO can be very basic system components. If we don't
> print this, defer a few times (for some reason) and then
> the kernel gives up on retrying, silently (as it happens)
> there is no trace in dmesg of what happened. That makes
> things hard to debug.
>
> This happened to me with some other driver, so it is not
> a made up example.
>
> What about an explicit deferral message for now?
>

The DD has debuging prints for all cases, so in general it can be used
for boot debugging (really_probe()). So, in my opinion it make sense to
print gpiolib specific message only in case of !EPROBE_DEFER.

5c

--
regards,
-grygorii