linux-kernel - Re: [PATCH 01/10] pwm-backlight: Refactor backlight power on/off

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20131001203430.GA9201@ulmo.nvidia.com>
Date:	Tue, 1 Oct 2013 22:34:34 +0200
From:	Thierry Reding <thierry.reding@...il.com>
To:	Stephen Warren <swarren@...dotorg.org>
Cc:	Rob Herring <rob.herring@...xeda.com>,
	Pawel Moll <pawel.moll@....com>,
	Mark Rutland <mark.rutland@....com>,
	Ian Campbell <ijc+devicetree@...lion.org.uk>,
	Tony Lindgren <tony@...mide.com>,
	Eric Miao <eric.y.miao@...il.com>,
	Haojian Zhuang <haojian.zhuang@...il.com>,
	Ben Dooks <ben-linux@...ff.org>,
	Kukjin Kim <kgene.kim@...sung.com>,
	Simon Horman <horms@...ge.net.au>,
	Magnus Damm <magnus.damm@...il.com>,
	Guan Xuetao <gxt@...c.pku.edu.cn>, devicetree@...r.kernel.org,
	linux-arm-kernel@...ts.infradead.org, linux-omap@...r.kernel.org,
	openezx-devel@...ts.openezx.org, linux-samsung-soc@...r.kernel.org,
	linux-sh@...r.kernel.org, linux-pwm@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 01/10] pwm-backlight: Refactor backlight power on/off

On Tue, Oct 01, 2013 at 12:26:07PM -0600, Stephen Warren wrote:
> On 09/23/2013 03:40 PM, Thierry Reding wrote:
> > In preparation for adding an optional regulator and enable GPIO to the
> > driver, split the power on and power off sequences into separate
> > functions to reduce code duplication at the multiple call sites.
> 
> > diff --git a/drivers/video/backlight/pwm_bl.c b/drivers/video/backlight/pwm_bl.c
> 
> > +static void pwm_backlight_power_off(struct pwm_bl_data *pb)
> > +{
> > +	pwm_disable(pb->pwm);
> 
> Both the call-sites you're replacing do the following before pwm_disable():
> 
> 		pwm_config(pb->pwm, 0, pb->period);
> 
> While I agree that probably shouldn't be necessary, I think it's at
> least worth mentioning that in the commit description just to make it
> obvious that it was a deliberate change. Splitting that change into a
> separate patch might be reasonable in order to keep refactoring and
> functional changes separate, although perhaps it's not worth it.

Actually I'll add that back. I'm not sure exactly why I dropped it (it
may just have been oversight) and there have been reports that some HW
actually requires pwm_config(..., 0, ...) before pwm_disable() to turn
off properly.

> There are also a couple unrelated whitespace changes thrown in here.

I think they increase readability, but I can certainly move them into a
separate patch.

Thierry

Content of type "application/pgp-signature" skipped