From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vincent Pelletier Subject: Re: [1/4] gpio: gpio-f7188x: Use mutex for access serialisation. Date: Sat, 12 Sep 2015 15:26:43 +0200 Message-ID: <20150912152643.4e5bb384@x2> References: <1440093809-18234-1-git-send-email-plr.vincent@gmail.com> <7d1a2156ddabe0b72964e88734adba307a472067.1440093298.git.plr.vincent@gmail.com> <20150821175216.GE1729@kw.sim.vm.gnt> <20150821224824.3406caa0@x2> <20150903200540.399a96b8@x2> <20150909220140.GD9892@kw.sim.vm.gnt> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wi0-f182.google.com ([209.85.212.182]:35864 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754720AbbILN0r (ORCPT ); Sat, 12 Sep 2015 09:26:47 -0400 In-Reply-To: <20150909220140.GD9892@kw.sim.vm.gnt> Sender: linux-gpio-owner@vger.kernel.org List-Id: linux-gpio@vger.kernel.org To: Simon Guinot Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org, Vincent Donnefort , Yoann Sculo Hello Simon, On Thu, 10 Sep 2015 00:01:40 +0200, Simon Guinot wrote: > Vincent (Donnefort) finally succeeds to reproduce the issue. The setup > is quite simple. You only have to flood the gpio-f7188x driver via the > sysfs GPIO interface. Nothing more is needed. > > After some debugging we discovered that the problem comes from the > __request_region function which don't handle very well concurrent > requests on a muxed region. > > I will send a patch as a reply to this email. Please, can you test it ? I reverted my mutex-adding commit, applied given patch, and could not reproduce the error after a few minutes with my test-case, so I think this solves the issue. Tested-by: Vincent Pelletier I rebased my others gpio patches, unrelated to this issue: gpio: gpio-f7188x: Implement get_direction. gpio: gpio-f7188x: "get" should retrieve sensed level when available. gpio: gpio-f7188x: GPIO bank 0 bit 0 is not available on f71869a Should I resend ? I have not checked other model's datasheets, FWIW. Regards, -- Vincent Pelletier