From: Sangbeom Kim Date: Mon, 18 Jun 2012 00:49:20 +0000 (+0900) Subject: regulator: s5m8767a: Support AP watchdog reset operation X-Git-Tag: v3.6-rc1~157^2^2~82 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c848bc8538cd29e92223d5e72e8fb60e6f2e176e;p=pandora-kernel.git regulator: s5m8767a: Support AP watchdog reset operation The S5M8767A can't know status of ap reset. So, After AP watchdog reset, AP can't boot normally. Problem can be happened like below condition. - AP Bootable lowest voltage(vdd_arm): 0.9v - AP DVFS voltage table: 0.8v, 0.9v, 1.0v - During AP works on lowest voltage(0.8V), watchdog reset is asserted - AP can't boot, because vdd arm is still 0.8v Solution - Basic concept: After ap watchdog reset, GPIO configuration is changed by default value - S5M8767A has function of voltage control with gpio (8 levels with 3 gpios) - Set bootable voltage on level 0 -> can work with default gpio configuration - In the probing, Change voltage control level from level 0 to level 1 - Execute normal dvfs operation on level 1 - After watchdog reset, ap gpio is set by default value - PMIC operation mode is changed by ap reset (level1 -> level0) - Regardless of previous vdd_arm voltage, AP always can be booted. Signed-off-by: Sangbeom Kim Signed-off-by: Mark Brown --- Reading git-diff-tree failed