linux-kernel - Re: [PATCH] spi: sirf: add reset controller dependency

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]

Date:	Mon, 23 Feb 2015 23:01:18 +0100
From:	Arnd Bergmann <arnd@...db.de>
To:	Mark Brown <broonie@...nel.org>
Cc:	linux-arm-kernel@...ts.infradead.org,
	Barry Song <Baohua.Song@....com>, linux-kernel@...r.kernel.org,
	linux-spi@...r.kernel.org, Philipp Zabel <p.zabel@...gutronix.de>,
	Maxime Ripard <maxime.ripard@...e-electrons.com>,
	Marek Vasut <marex@...x.de>, Wolfram Sang <wsa@...-dreams.de>
Subject: Re: [PATCH] spi: sirf: add reset controller dependency

On Saturday 21 February 2015 18:44:58 Mark Brown wrote:
> On Thu, Feb 19, 2015 at 04:01:29PM +0100, Arnd Bergmann wrote:
> 
> > So the stubs are provided for all functions except device_reset() and
> > reset_control_get(), and drivers using the API need to either call the
> > stubbed-out _optional() versions of these functions or have the explicit
> > dependency.
> 
> In that case a dependency seems wrong, I'd expect to see a select - it's
> a bit obscure to have to grovel around to figure out what magic options
> are needed to make things turn on and resets feel more like a utility
> thing than a control bus (which tend to be the things we depend on).
> Dunno, perhaps I'm wrong?

Mixing 'select' and 'depends on' causes recursive dependencies, and
there are already lots of drivers that do 'depends on RESET_CONTROLLER'.

Most users of this symbol seem to follow the strategy of selecting
RESET_CONTROLLER when a driver is there to provide the functionality,
but depending on it when a driver uses it. We are however a bit
inconsistent here and it would be nice to clean it up.

In this particular patch, I'm just following what others do.

We should probably 'select ARCH_HAS_RESET_CONTROLLER' unconditionally
for ARM ARCH_MULTIPLATFORM, as it's a bit silly to select both
ARCH_HAS_RESET_CONTROLLER and RESET_CONTROLLER from platform code.

	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/