Date: Wed, 10 Jun 2015 12:22:36 +0100
From: Russell King - ARM Linux <linux@arm.linux.org.uk>
To: Nicholas Mc Guire <hofrat@osadl.org>
Cc: David Airlie <airlied@linux.ie>, dri-devel@lists.freedesktop.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] DRM: Armada: fixup wait_event_timeout being ignored
Message-ID: <20150610112235.GL7557@n2100.arm.linux.org.uk>
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On Wed, Jun 10, 2015 at 01:07:08PM +0200, Nicholas Mc Guire wrote:
> The calling side seems to assume 0 as success and <0 as error so 
> returning -ETIME should be fine here.

The idea here is to allow the remainder of the code to execute when
the condition succeeds _or_ times out.  If it times out, that is
not a failure - it merely means that the display has been blanked
and we're not seeing frame done interrupts anymore.

The code should not be checking the returned value at all - in fact
I have updates to this code which (in part) remove this, and fix a
glaring problem that the wait queue is never woken.

I wonder how many places you've made this same mistake... please
ensure that you review the code you're changing carefully.

-- 
FTTC broadband for 0.8mile line: currently at 10.5Mbps down 400kbps up
according to speedtest.net.
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