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From: Jacek Anaszewski <jacek.anaszewski@gmail.com>
To: Pavel Machek <pavel@ucw.cz>, Heiner Kallweit <hkallweit1@gmail.com>
Cc: Richard Purdie <rpurdie@rpsys.net>,
	"linux-leds@vger.kernel.org" <linux-leds@vger.kernel.org>
Subject: Re: [PATCH v2] leds: core: use deferred probing if default trigger isn't available yet
Date: Mon, 27 Feb 2017 20:55:41 +0100	[thread overview]
Message-ID: <a5149ede-f0c3-2fba-54ce-b137fec96e94@gmail.com> (raw)
In-Reply-To: <20170227111213.GA19403@amd>

On 02/27/2017 12:12 PM, Pavel Machek wrote:
> On Fri 2017-02-24 07:41:48, Heiner Kallweit wrote:
>> When registering a LED device we have the option to set a default trigger.
>> Depending on load order of drivers this trigger may not be available yet.
>> (affected LED device in my case: a DT-configured GPIO LED)
>> So far if the default trigger can't be found this error is silently
>> ignored.
>>
>> Let's change this to return EPROBE_DEFER if the default trigger can't be
>> found. This gives the system the chance to probe the LED device later
>> once the trigger is available.
>>
>> In addition in led_trigger_set_default break out of the loop when trigger
>> has been found.
> 
> Hmm. Problem with this is that if the we configure non-existing
> trigger, or trigger not configured in current kernel, LED will
> disappear and user will have "fun" debugging why, right?

Right, so I propose to add suitable dev_err logging in
led_classdev_register() if led_trigger_set_default() returns
non-zero.

-- 
Best regards,
Jacek Anaszewski

      reply	other threads:[~2017-02-27 21:36 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-02-24  6:41 [PATCH v2] leds: core: use deferred probing if default trigger isn't available yet Heiner Kallweit
2017-02-26 17:11 ` Jacek Anaszewski
2017-02-27 11:12 ` Pavel Machek
2017-02-27 19:55   ` Jacek Anaszewski [this message]

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