From: Axel Lin Date: Wed, 17 Apr 2013 13:42:23 +0000 (+0800) Subject: regulator: tps80031: Fix LDO2 track mode for TPS80031 or TPS80032-ES1.0 X-Git-Tag: omap-for-v3.10/dt-fixes-for-merge-window~131^2~2^2~1 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=58fa6ab42c29156b2808f8db231b2ffd8fa25502;p=pandora-kernel.git regulator: tps80031: Fix LDO2 track mode for TPS80031 or TPS80032-ES1.0 Currently we have a special code in tps80031_ldo_set_voltage_sel() to handle LDO2 track mode for TPS80031 or TPS80032-ES1.0. The purpose is to address below issues: Issue description: - LDO2 traking mode is enabled - LDO2 tracks SMPS2 voltage. - LDO2 automatically switch-off when LDO2_CFG_VOLTAGE is changed to some discrete values (non exhaustive list): 00011001, 00011010, 00011011, 00011100, . - LDO2 switch-on again when LDO2_CFG_VOLTAGE is changed to other values (non exhaustive list): 00011000, 00010111, . LDOs have reserved codes. For these codes, LDO is switch-off. In tracking, LDO2 ref comes from SMPS2. However LDO2 enable is still gated by LDO2 VSEL decoding. As a result, in tracking mode LDO2 will be disabled for following code (SMPS VSEL format): 000000 & 100000 (MSB not decoded) 011001 & 111001 (MSB not decoded) 011010 & 111010 (MSB not decoded) 011100 & 111100 (MSB not decoded) 011101 & 111101 (MSB not decoded) 011110 & 111110 (MSB not decoded) However, current code has below bugs: 1. It uses regulator_list_voltage_linear, so list_voltage() still shows above invalid selectors have supported voltage. 2. Current code may return -EINVAL in tps80031_ldo_set_voltage_sel() for supported voltage. This is because when we use regulator_list_voltage_linear as list_voltage callback, regulator core will default use regulator_map_voltage_linear(). regulator_map_voltage_linear() has an assumption that the voltages are linear which is not true for this case. For example, when request voltage range is: min_uV=950000 uV && max_uV=1200000 uV regulator_map_voltage_linear() returns the selector is 29 (0x1D), set_voltage_sel() returns -EINVAL. (The selector is in invalid range, 0x19 ~ 0x1f). In above case, map_voltage() should find the lowest valid voltage within specific range (selector = 0x20) and set_voltage_sel() should successfully set the voltage to 987500 uV. This patch fixes these issues by: 1. Add checking valid setting for LDO2 track mode of TPS80031 or TPS80032-ES1.0 in list_voltage. So it returns -EINVAL for invalid selectors. 2. Implement tps80031_ldo_map_voltage, use regulator_map_voltage_iterate() to find the lowest voltage within specific range for TPS80031 or TPS80032-ES1.0. This is required when the voltage map is no longer linear. Signed-off-by: Axel Lin Signed-off-by: Mark Brown --- Reading git-diff-tree failed