From mboxrd@z Thu Jan 1 00:00:00 1970 From: w.sang@pengutronix.de (Wolfram Sang) Date: Thu, 12 Jul 2012 14:22:08 +0200 Subject: [PATCHv11 6/6] i2c: omap: Recover from Bus Busy condition In-Reply-To: <1340896292-12112-7-git-send-email-shubhrajyoti@ti.com> References: <1340896292-12112-1-git-send-email-shubhrajyoti@ti.com> <1340896292-12112-7-git-send-email-shubhrajyoti@ti.com> Message-ID: <20120712122208.GF2194@pengutronix.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Thu, Jun 28, 2012 at 08:41:32PM +0530, Shubhrajyoti D wrote: > From: Vikram Pandita > > In case a peripheral is driving SDA bus low (ie. a start condition), provide > a constant clock output using the test mode of the OMAP I2C controller to > try and clear the bus. Soft reset I2C controller after attempting the bus clear > to ensure that controller is in a good state. > > Based upon Vikram Pandita's patch from TI Android 3.0. > I acknowledge the contributions and suggestions of Jon and Hemant. > > A couple differences from the original patch ... > 1. Add a new function for bus clear > 2. Ensure that the CON.I2C_EN bit is set when using the SYSTEST feature to > output a permanent clock. This bit needs to be set and typically it would > be set by the unidle function but this is not the case for all OMAP > generations. > 3. Program the SYSTEST setting only the bits we care about. However, restore > SYSTEST registers to there original state as some OMAP generations do not > implement perform a soft-reset. > 4. Clear the CON register after performing the bus clear, so when we call the > init function the controller is disabled and the init function will > re-enable later. > > Original patch can be found here: > http://git.omapzoom.org/?p=kernel/omap.git;a=commit;h=a2ab04192ba25e60f95ba1ff3af5601a2d7b5bd1 > > Signed-off-by: Vikram Pandita > Signed-off-by: Jon Hunter > Signed-off-by: Shubhrajyoti D This has to wait a little bit until I can spend time on the recovery framework (which is still in the queue, sadly :( ). There might be some consolidation. -- Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ | -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 198 bytes Desc: Digital signature URL: