From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leo Li Subject: Re: [PATCH v5] i2c: imx: make bus recovery through pinctrl optional Date: Mon, 12 Sep 2016 11:35:39 -0500 Message-ID: References: <1471644322-22670-1-git-send-email-leoyang.li@nxp.com> <20160906185849.27pjhawadca5pwow@pengutronix.de> <87ca69fb85848a0a86b34a9a9037a57b@agner.ch> <20160907055547.opp57zyxhlplhxhm@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Tracy Smith Cc: =?UTF-8?Q?Uwe_Kleine=2DK=C3=B6nig?= , "linux-i2c@vger.kernel.org" , Wolfram Sang , "linux-arm-kernel@lists.infradead.org" , linux-gpio@vger.kernel.org, Li Yang , Stefan Agner , Gao Pan , lkml List-Id: linux-i2c@vger.kernel.org On Wed, Sep 7, 2016 at 5:07 AM, Tracy Smith wrote: > Hello, bus recovery is needed generally speaking because of potential > protocol errors that might cause a failure condition hanging the bus. > > It happens frequently during bring-up of new I2C devices because firmware in > I2C controllers fail to handle properly protocol errors. > > Can NXP add bus recovery for the LS1021A and LS1043A in a separate patch-- > unless there is no HW bus recovery mechanism? > > The concern is while fixing I.MX, NXP will fail to fix the driver bus > recovery for the LS1021A and LS1043A and the bus will hang. > > If bus recovery is supported on the LS1021A and the LS1043A, a patch should > be provided or added in this patch instead of simply disabling bus recovery. > Request NXP to consider the patch if there is HW support for bus recovery. FYI. http://patchwork.ozlabs.org/patch/573879/ This seem to be the patch you are asking for. I have asked the original developer to update the patch according to Wolfram's comment and work together with the current pinctrl/gpio based recovery. In the meanwhile you can make use of the patch for now for LS1021A and LS1043A if necessary. Regards, Leo