Date: Wed, 9 Nov 2016 13:38:00 +0100
From: Pavel Machek <pavel@ucw.cz>
To: Jacek Anaszewski <j.anaszewski@samsung.com>
Cc: linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org,
        Hans de Goede <hdegoede@redhat.com>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        Andrew Lunn <andrew@lunn.ch>
Subject: Re: [PATCH] leds: Add mutex protection in brightness_show()
Message-ID: <20161109123800.GB3488@amd>
References: <1478245962-15706-1-git-send-email-j.anaszewski@samsung.com>
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Hi!

> Initially the claim about no need for lock in brightness_show()
> was valid as the function was just returning unchanged
> LED brightness. After the addition of led_update_brightness() this

The claim was probably wrong from the day one, unless brightness is of
type "atomic_t".

             /* Ensures consistent access to the LED Flash Class device */
	        struct mutex            led_access;
		};

This should really list fields that are protected by led_access.

Thanks,
									Pavel
--=20
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blo=
g.html

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