From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laurent Pinchart Date: Thu, 22 Oct 2015 11:12:03 +0000 Subject: Re: [PATCH 5/9] i2c: rcar: init new messages in irq Message-Id: <1917001.aD8sIkvx7f@avalon> List-Id: References: <1441311613-2681-1-git-send-email-wsa@the-dreams.de> <131418014.1WnDGNUZcn@avalon> <20151022110505.GB1572@katana> In-Reply-To: <20151022110505.GB1572@katana> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Wolfram Sang Cc: linux-i2c@vger.kernel.org, linux-sh@vger.kernel.org, Magnus Damm , Simon Horman , Geert Uytterhoeven , Kuninori Morimoto , Yoshihiro Kaneko , Sergei Shtylyov Hi Wolfram, On Thursday 22 October 2015 13:05:05 Wolfram Sang wrote: > On Thu, Oct 22, 2015 at 02:10:52AM +0300, Laurent Pinchart wrote: > > On Thursday 03 September 2015 22:20:09 Wolfram Sang wrote: > > > From: Wolfram Sang > > > > > > Setting up new messages was done in process context while handling a > > > message was in interrupt context. Because of the HW design, this IP core > > > is sensitive to timing, so the context switches were too expensive. Move > > > this setup to interrupt context as well. > > > > > > In my test setup, this fixed the occasional 'data byte sent twice' issue > > > which a number of people have seen. It also fixes to send REP_START > > > after a read message which was wrongly send as a STOP + START sequence > > > before. > > > > I'm afraid this patch has been found by git bisect to break HDMI on > > Koelsch > > > > :-( > > > > The regmap_read(adv7511->regmap, ADV7511_REG_CHIP_REVISION, &val) call in > > drivers/gpu/drm/i2c/adv7511.c returns -ENXIO. > > > > Reverting the patch on top of Geert's current drivers master branch fixes > > the problem. > > But HDMI worked on Koelsch in Dublin?? I know :-) Do you have a Koelsch board now ? Could you try b9653e9c000dc2ebd9c8712442c659ccd1586e22 from Geert's drivers tree ? On my board the adv7511 fails to probe completely due to the regmap_read() failure. -- Regards, Laurent Pinchart