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Subject[PATCH v3 05/16] bq27x00: Fix CURRENT_NOW property
Date
From: Pali Rohár <pali.rohar@gmail.com>

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 files changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/power/bq27x00_battery.c b/drivers/power/bq27x00_battery.c
index 4f74659..1b06134 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;
}

/*
--
1.7.2.3
--
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