From mboxrd@z Thu Jan 1 00:00:00 1970 From: wsa@the-dreams.de (Wolfram Sang) Date: Fri, 12 Feb 2016 19:38:15 +0100 Subject: [PATCH V7 3/6] i2c: qup: Transfer each i2c_msg in i2c_msgs without a stop bit In-Reply-To: <1453197766-18976-4-git-send-email-sricharan@codeaurora.org> References: <1453197766-18976-1-git-send-email-sricharan@codeaurora.org> <1453197766-18976-4-git-send-email-sricharan@codeaurora.org> Message-ID: <20160212183815.GD1520@katana> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Jan 19, 2016 at 03:32:43PM +0530, Sricharan R wrote: > The definition of i2c_msg says that > > "If this is the last message in a group, it is followed by a STOP. > Otherwise it is followed by the next @i2c_msg transaction segment, > beginning with a (repeated) START" > > So the expectation is that there is no 'STOP' bit inbetween individual > i2c_msg segments with repeated 'START'. The QUP i2c hardware has no way > to inform that there should not be a 'STOP' at the end of transaction. > The only way to implement this is to coalesce all the i2c_msg in i2c_msgs > in to one transaction and transfer them. Adding the support for the same. > > This is required for some clients like touchscreen which keeps > incrementing counts across individual transfers and 'STOP' bit inbetween > resets the counter, which is not required. > > This patch adds the support in non-dma mode. > > Signed-off-by: Sricharan R > Reviewed-by: Andy Gross > Tested-by: Archit Taneja > Tested-by: Telkar Nagender Shortened the commit message and applied to for-next, thanks! -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: