linux-kernel - Re: [PATCH 1/2] Input: spear-keyboard - Fix a double put in spear_kbd

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Message-ID: <ZqLJ4mZaKgzPVMFb@google.com>
Date: Thu, 25 Jul 2024 14:55:46 -0700
From: Dmitry Torokhov <dmitry.torokhov@...il.com>
To: Christophe JAILLET <christophe.jaillet@...adoo.fr>
Cc: vipulkumar.samar@...com, viresh.kumar@...aro.org,
	linux-input@...r.kernel.org, linux-kernel@...r.kernel.org,
	kernel-janitors@...r.kernel.org
Subject: Re: [PATCH 1/2] Input: spear-keyboard - Fix a double put in
 spear_kbd_remove()

On Thu, Jul 25, 2024 at 11:34:14PM +0200, Christophe JAILLET wrote:
> Le 25/07/2024 à 22:52, Dmitry Torokhov a écrit :
> > Hi Christophe,
> > 
> > On Thu, Jul 25, 2024 at 10:46:49PM +0200, Christophe JAILLET wrote:
> > > The 'input_dev' is a managed resource allocated with
> > > devm_input_allocate_device(), so there is no need to call
> > > input_unregister_device() in the remove function.
> > > 
> > > In fact, this call was correctly removed in commit 6102752eb354 ("Input:
> > > spear-keyboard - switch to using managed resources"), but silently
> > > re-introduced later in the commit in Fixes.
> > 
> > This change is incorrect as it leads to an active and enabled clock
> > being unprepared to early. We need to unregister input device which in
> > turn will call spear_kbd_close() if needed which will disable the clock
> > in question. Only after that we can unprepare it.
> > 
> > There is also no double put as input core will recognize that input
> > device was unregistered explicitly and will not attempt to unregister it
> > 2nd time through devm:
> 
> Got it.
> 
> Thanks for the review and the detailed explanation.
> Sorry for the noise.
> 
> I'll resend as asked in patch 2/2, if saving some lines of code makes enough
> sense for you.
> But as said in the cover letter, if there is no issue, I'm not sure it worth
> the time for an old driver.

I generally like infrastructure cleanups, unless it is too much trouble.

Thanks.

-- 
Dmitry