From 7384b0e7668f722fcf7abe56f61a7212debd0180 Mon Sep 17 00:00:00 2001 From: Yuanjiang Yu Date: Wed, 31 Jul 2019 18:00:25 +0800 Subject: [PATCH] power: supply: sc27xx: Fix the the accuracy issue of coulomb calculation The Spreadtrum fuel gauge will multiply by 2 for counting the coulomb counter to improve the accuracy, which means the value saved in fuel gauge is: coulomb counter * 2 * 1000ma_adc. Thus fix the conversion formular to improve the accuracy of calculating the battery capacity. Signed-off-by: Yuanjiang Yu Signed-off-by: Baolin Wang Signed-off-by: Sebastian Reichel --- drivers/power/supply/sc27xx_fuel_gauge.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/drivers/power/supply/sc27xx_fuel_gauge.c b/drivers/power/supply/sc27xx_fuel_gauge.c index db7d07d5dae9..6a29f00aec48 100644 --- a/drivers/power/supply/sc27xx_fuel_gauge.c +++ b/drivers/power/supply/sc27xx_fuel_gauge.c @@ -326,8 +326,6 @@ static int sc27xx_fgu_set_clbcnt(struct sc27xx_fgu_data *data, int clbcnt) { int ret; - clbcnt *= SC27XX_FGU_SAMPLE_HZ; - ret = regmap_update_bits(data->regmap, data->base + SC27XX_FGU_CLBCNT_SETL, SC27XX_FGU_CLBCNT_MASK, clbcnt); @@ -362,7 +360,6 @@ static int sc27xx_fgu_get_clbcnt(struct sc27xx_fgu_data *data, int *clb_cnt) *clb_cnt = ccl & SC27XX_FGU_CLBCNT_MASK; *clb_cnt |= (cch & SC27XX_FGU_CLBCNT_MASK) << SC27XX_FGU_CLBCNT_SHIFT; - *clb_cnt /= SC27XX_FGU_SAMPLE_HZ; return 0; } @@ -380,10 +377,10 @@ static int sc27xx_fgu_get_capacity(struct sc27xx_fgu_data *data, int *cap) /* * Convert coulomb counter to delta capacity (mAh), and set multiplier - * as 100 to improve the precision. + * as 10 to improve the precision. */ - temp = DIV_ROUND_CLOSEST(delta_clbcnt, 360); - temp = sc27xx_fgu_adc_to_current(data, temp); + temp = DIV_ROUND_CLOSEST(delta_clbcnt * 10, 36 * SC27XX_FGU_SAMPLE_HZ); + temp = sc27xx_fgu_adc_to_current(data, temp / 1000); /* * Convert to capacity percent of the battery total capacity, @@ -790,7 +787,7 @@ static int sc27xx_fgu_cap_to_clbcnt(struct sc27xx_fgu_data *data, int capacity) * Convert current capacity (mAh) to coulomb counter according to the * formula: 1 mAh =3.6 coulomb. */ - return DIV_ROUND_CLOSEST(cur_cap * 36 * data->cur_1000ma_adc, 10); + return DIV_ROUND_CLOSEST(cur_cap * 36 * data->cur_1000ma_adc * SC27XX_FGU_SAMPLE_HZ, 10); } static int sc27xx_fgu_calibration(struct sc27xx_fgu_data *data)