linux-kernel - Re: [PATCH 3/4] pinctrl: Add support for additional dynamic states

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: <CACRpkdbHj8R-ZFa2FB-pxcvgBRYH=1KKGNEbWieAnSZSv5LHaQ@mail.gmail.com>
Date:	Tue, 23 Jul 2013 01:15:13 +0200
From:	Linus Walleij <linus.walleij@...aro.org>
To:	Stephen Warren <swarren@...dotorg.org>
Cc:	Grygorii Strashko <grygorii.strashko@...com>,
	Tony Lindgren <tony@...mide.com>,
	Linux-OMAP <linux-omap@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH 3/4] pinctrl: Add support for additional dynamic states

On Fri, Jul 19, 2013 at 9:03 PM, Stephen Warren <swarren@...dotorg.org> wrote:
> On 07/19/2013 04:29 AM, Grygorii Strashko wrote:

>> First of all, I'd like to mention that these patches do *not* connect
>> pinctrl to PM runtime, so until driver will call pinctrl_select_state()
>> or pinctrl_pm_select_*() there will be no pins state changes.
>
> Isn't the whole point of the pinctrl_pm_select*() APIs to eventually be
> called automatically by the runtime PM core,

Nah I had no such complete ambitions, just factoring around.

There are examples, such as deactivating a TTY from userspace,
that should result in the pins going to sleep while it may have nothing
to do with runtime PM.

> so that we don't need to
> write code to do this in every single driver, just like we moved the
> call to pinctrl_select_state(default) into the device core so that we
> didn't have to make every device do that manually?

I am pretty convinced that if this dynamic muxing stuff shall be
implemented, it should be a pinctrl subsystem intrinsic optimization
detail and should not be exposed to the outside with all these extra
functions at all. It looks overly complicated to me.

Yours,
Linus Walleij
--
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/