From a2e5118c370e78c3841606e7edc7677c986325fa Mon Sep 17 00:00:00 2001 From: Pali Rohár <pali.rohar@gmail.com> Date: Mon, 24 May 2010 20:52:13 +0200 Subject: bq27x00: Fix CURRENT_NOW property MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit According to the bq27000 datasheet the current should be calculated by the following formula: current = AI * 3570 / 20 This patch adjust the drivers code accordingly. Signed-off-by: Pali Rohár <pali.rohar@gmail.com> Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Rodolfo Giometti <giometti@linux.it> Tested-by: Grazvydas Ignotas <notasas@gmail.com> --- drivers/power/bq27x00_battery.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) (limited to 'drivers/power') diff --git a/drivers/power/bq27x00_battery.c b/drivers/power/bq27x00_battery.c index 4f7465999c86..1b06134e0ae8 100644 --- a/drivers/power/bq27x00_battery.c +++ b/drivers/power/bq27x00_battery.c @@ -44,6 +44,8 @@ #define BQ27500_FLAG_DSC BIT(0) #define BQ27500_FLAG_FC BIT(9) +#define BQ27000_RS 20 /* Resistor sense */ + /* If the system has several batteries we need a different name for each * of them... */ @@ -149,7 +151,7 @@ static int bq27x00_battery_current(struct bq27x00_device_info *di) if (di->chip == BQ27500) { /* bq27500 returns signed value */ - curr = (int)(s16)curr; + curr = (int)((s16)curr) * 1000; } else { ret = bq27x00_read(BQ27x00_REG_FLAGS, &flags, 0, di); if (ret < 0) { @@ -160,9 +162,10 @@ static int bq27x00_battery_current(struct bq27x00_device_info *di) dev_dbg(di->dev, "negative current!\n"); curr = -curr; } + curr = curr * 3570 / BQ27000_RS; } - return curr * 1000; + return curr; } /* -- cgit v1.2.3