From: Pavel Machek <pavel@ucw.cz>
To: Jacek Anaszewski <j.anaszewski@samsung.com>,
Greg KH <greg@kroah.com>,
kernel list <linux-kernel@vger.kernel.org>
Cc: linux-leds@vger.kernel.org, devicetree@vger.kernel.org,
kyungmin.park@samsung.com, b.zolnierkie@samsung.com,
cooloney@gmail.com, rpurdie@rpsys.net, sakari.ailus@iki.fi,
s.nawrocki@samsung.com
Subject: Reading /sys with side effects (was Re: [PATCH 1/2] Documentation: leds: Add description of LED Flash class extension)
Date: Tue, 27 Jan 2015 23:37:08 +0100 [thread overview]
Message-ID: <20150127221958.GA18993@amd> (raw)
In-Reply-To: <1422346028-16739-1-git-send-email-j.anaszewski@samsung.com>
Hi!
> + - flash_fault - list of flash faults that may have occurred:
> + * led-over-voltage - flash controller voltage to the flash LED
> + has exceededthe limit specific to the flash controller
> + * flash-timeout-exceeded - the flash strobe was still on when
> + the timeout set by the user has expired; not all flash
> + controllers may set this in all such conditions
> + * controller-over-temperature - the flash controller has
> + overheated
> + * controller-short-circuit - the short circuit protection
> + of the flash controller has been triggered
> + * led-power-supply-over-current - current in the LED power
> + supply has exceeded the limit specific to the flash
> + controller
> + * indicator-led-fault - the flash controller has detected
> + a short or open circuit condition on the indicator LED
> + * led-under-voltage - flash controller voltage to the flash
> + LED has been below the minimum limit specific to
> + the flash
> + * controller-under-voltage - the input voltage of the flash
> + controller is below the limit under which strobing the
> + flash at full current will not be possible. The condition
> + persists until this flag is no longer set
> + * led-over-temperature - the temperature of the LED has exceeded
> + its allowed upper limit
> +
> + Flash faults are cleared, if possible, by reading the attribute.
That's bad. Now you can no longer present flash_fault file as readable
to non-root users, and grep -ri foo /sys will interfere with your
camera application.
Bad interface, just fix it.
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
next prev parent reply other threads:[~2015-01-27 22:37 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-01-27 8:07 [PATCH 1/2] Documentation: leds: Add description of LED Flash class extension Jacek Anaszewski
2015-01-27 8:07 ` [PATCH 2/2] DT: leds: Add led-sources property Jacek Anaszewski
2015-01-29 14:55 ` Jacek Anaszewski
2015-01-29 20:28 ` Pavel Machek
2015-01-29 21:03 ` Rob Herring
2015-01-29 22:14 ` Bryan Wu
[not found] ` <CAK5ve-LKBfjRzxK_b0ByEF5uWHfAaBGS2OPznOiYNg9+FJP5Gg-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2015-01-29 22:30 ` Pavel Machek
2015-01-29 22:59 ` Bryan Wu
2015-01-27 22:37 ` Pavel Machek [this message]
2015-01-28 8:43 ` Reading /sys with side effects (was Re: [PATCH 1/2] Documentation: leds: Add description of LED Flash class extension) Jacek Anaszewski
[not found] ` <54C8A130.8000807-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org>
2015-01-29 21:14 ` Pavel Machek
2015-01-29 21:14 ` Pavel Machek
2015-01-30 8:55 ` Jacek Anaszewski
2015-01-30 16:40 ` Greg KH
2015-02-02 9:07 ` Jacek Anaszewski
2015-02-02 9:44 ` Pavel Machek
2015-02-02 11:55 ` Jacek Anaszewski
2015-02-02 13:51 ` Pavel Machek
2015-02-02 14:51 ` Jacek Anaszewski
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