From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Torokhov Subject: Re: [PATCH 3/3] Input: mms114 - add support for mms345l Date: Tue, 8 Oct 2019 15:00:14 -0700 Message-ID: <20191008220014.GI22365@dtor-ws> References: <20191007203343.101466-1-stephan@gerhold.net> <20191007205021.104402-1-stephan@gerhold.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20191007205021.104402-1-stephan@gerhold.net> Sender: linux-kernel-owner@vger.kernel.org To: Stephan Gerhold Cc: Andi Shyti , Simon Shields , linux-input@vger.kernel.org, Rob Herring , Mark Rutland , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: devicetree@vger.kernel.org On Mon, Oct 07, 2019 at 10:50:21PM +0200, Stephan Gerhold wrote: > MMS345L is another first generation touch screen from Melfas, > which uses the same registers as MMS152. > > However, using I2C_M_NOSTART for it causes errors when reading: > > i2c i2c-0: sendbytes: NAK bailout. > mms114 0-0048: __mms114_read_reg: i2c transfer failed (-5) > > The driver works fine as soon as I2C_M_NOSTART is removed. > > Add a separate melfas,mms345l binding, and make use of I2C_M_NOSTART > only for MMS114 and MMS152. > > Signed-off-by: Stephan Gerhold > --- > Note: I was not able to find a datasheet for any of the models, > so this change is merely based on testing and comparison with > the downstream driver [1]. > > There was a related patch [2] that removes I2C_M_NOSTART for all models, > but it seems abandoned and I do not have any other model for testing. > Therefore, this patch implements the least instrusive solution > and only removes I2C_M_NOSTART for MMS345L. Hmm, at this point I am inclined to pick up Andi's patch since it seems to work for you and him and it looks like Android drivers are not using I2C_M_NOSTART. I wonder if this was some quirk/big on the platform where it was originally developed. Any objections? Thanks. -- Dmitry