bq27x00: Fix CURRENT_NOW property

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>

1 files changed, 5 insertions, 2 deletions

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;
 }
 
 /*