From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Subject: Re: [PATCH] i2c: mxs: fix broken timing calculation Date: Wed, 17 Jul 2013 19:54:59 +0200 Message-ID: <201307171954.59556.marex@denx.de> References: <1373041680-26939-1-git-send-email-LW@KARO-electronics.de> <201307151424.32248.marex@denx.de> <20965.3.293494.346855@ipc1.ka-ro> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <20965.3.293494.346855-VjFSrY7JcPWvSplVBqRQBQ@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Lothar =?iso-8859-1?q?Wa=DFmann?= Cc: Shawn Guo , Fabio Estevam , linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org Dear Lothar Wa=DFmann, > Hi, >=20 > Marek Vasut writes: > > > > btw offtopic, I will at least try to fix the PIO in the meantim= e. > > >=20 > > > Did you succeed at this? Because this is the real problem for the > > > DS1339 failing on our board. With DMA only transfers it works, bu= t > > > other chips (TSC2007, PCA9554, SGTL5000) fail. > >=20 > > Is that correct to assume that even DMA fails? So far I got to a pa= tch > > [1], which is almost an RFC, but please give it a go. I suspect I d= idn't > > CC you, I will CC you on V2. >=20 > I applied that patch and all the above mentioned devices seem to work > with it. > And with my patch the timing is also correct. =46irst, please accept my appology for the delay. I finally measured th= e bus.=20 Without this patch, I see 107khz at 100kHz setting and 410kHz at 400kHz= setting.=20 With this patch I see 93kHz and 307kHz respectively. I suspect the result really is board-dependent. Can you measure MX28EVK= so we=20 know what the result is there please? I don't have one here.=20 Best regards, Marek Vasut