From: Arnout Vandecappelle (Essensium/Mind) Date: Fri, 22 Aug 2014 15:30:56 +0000 (+0200) Subject: mfd: tps65910: Work around silicon erratum SWCZ010 X-Git-Tag: fixes-against-v3.18-rc2~69^2~48 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=be1c770028b832945680ebf5c0d49b831ba719d5;p=pandora-kernel.git mfd: tps65910: Work around silicon erratum SWCZ010 http://www.ti.com/lit/pdf/SWCZ010: Glitch on SDA-SCL not managed correctly by the I2C IP Impact: The standard specifies that the I2C transfer should restart on a start event in all cases. The current design does not support two consecutive Start conditions. This can cause the first real access after such a glitch to be corrupted. Description: An unexpected glitch on SDA and SCL can generate a wrong start event. In the current design, the SCL line must toggle two times to detect a new start event and completely restart the I2C access; hence the real start event is not detected in the case of a single SCL toggle. Workaround: Repeat I2C access. A simpler workaround is to make a dummy transfer just before the first access to the tps65910 chip. This can be done unconditionally. Signed-off-by: Arnout Vandecappelle (Essensium/Mind) Acked-by: Mark Brown Signed-off-by: Lee Jones --- Reading git-diff-tree failed