From mboxrd@z Thu Jan 1 00:00:00 1970 From: wsa@the-dreams.de (Wolfram Sang) Date: Wed, 26 Nov 2014 13:49:01 +0100 Subject: [PATCH 2/3] i2c: slave-eeprom: add eeprom simulator driver In-Reply-To: <2A7C987F-15E0-46FD-A711-E7F5BA9893FC@gmail.com> References: <1416326695-13083-1-git-send-email-wsa@the-dreams.de> <1416326695-13083-3-git-send-email-wsa@the-dreams.de> <20141122181229.GB9698@katana> <2A7C987F-15E0-46FD-A711-E7F5BA9893FC@gmail.com> Message-ID: <20141126124901.GB4397@katana> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Wed, Nov 26, 2014 at 03:25:29PM +0300, Alexander Kochetkov wrote: > > 22 ????. 2014 ?., ? 21:12, Wolfram Sang ???????(?): > > > IMO a repeated start is to ensure that two messages arrive at the slave > > without interruption from another master. I can't think why a slave > > should know which type of start that was. In fact, if it does that would > > raise an eyebrow for me. Do you have an example? > > It is used to implement Device ID reading. Yes and no, I'd say :) Technically, it needs repeated start. But really, the hardware should handle this (and I know one IP core which has support for it). One could try to simulate the behaviour in the bus driver IF a second slave address AND detection of repeated start is available, but I doubt this combination exists. Still, all the _slave driver_ needs to handle is an I2C_SLAVE_EVENT_DEVICE_ID which should return the apropriate value. That being said, I have never seen querying Device ID in action. > Not sure, that the feature is really needed for the first release. I am sure it is not :D Thanks, Wolfram -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: