linux-kernel - Re: [PATCH] backlight: add PWM dependencies

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: <201402061708.05845.arnd@arndb.de>
Date:	Thu, 6 Feb 2014 17:08:05 +0100
From:	Arnd Bergmann <arnd@...db.de>
To:	Jingoo Han <jg1.han@...sung.com>
Cc:	"'Linus Walleij'" <linus.walleij@...aro.org>,
	"'Thierry Reding'" <thierry.reding@...il.com>,
	"'Russell King - ARM Linux'" <linux@....linux.org.uk>,
	"'Eric Miao'" <eric.y.miao@...il.com>,
	linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
	linux-pwm@...r.kernel.org
Subject: Re: [PATCH] backlight: add PWM dependencies

On Thursday 06 February 2014, Jingoo Han wrote:
> In the case of "CONFIG_HAVE_PWM=y && CONFIG_PWM=n", it makes
> the problem.
> 
> The HAVE_PWM symbol is only for legacy platforms that provide
> the PWM API without using the generic framework. PXA looks to
> use the generic PWM framework. Then, how about removing
> "select HAVE_PWM" from PXA as below?
> 

I think this is correct, but we may need additional patches. I notice
that INPUT_MAX8997_HAPTIC and INPUT_PWM_BEEPER have a dependency on
HAVE_PWM at the moment, so those two drivers become impossible
to select after your change.

There is also one use of HAVE_PWM outside of PXA, for ARCH_LPC32XX.
This one seems to have the same problem.

Finally, I have recently encountered a couple of drivers
(BACKLIGHT_LM3630A, BACKLIGHT_LP855X, BACKLIGHT_LP8788) that use
the PWM interfaces but are missing a 'depends on PWM'. This is
strictly speaking a different problem, but we could try to solve
it at the same time.

	Arnd
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/