fixes for 4.19

[thirdparty/kernel/stable-queue.git] / releases / 4.4.170 / power-supply-olpc_battery-correct-the-temperature-units.patch

From ed54ffbe554f0902689fd6d1712bbacbacd11376 Mon Sep 17 00:00:00 2001
From: Lubomir Rintel <lkundrak@v3.sk>
Date: Fri, 16 Nov 2018 17:23:47 +0100
Subject: power: supply: olpc_battery: correct the temperature units

From: Lubomir Rintel <lkundrak@v3.sk>

commit ed54ffbe554f0902689fd6d1712bbacbacd11376 upstream.

According to [1] and [2], the temperature values are in tenths of degree
Celsius. Exposing the Celsius value makes the battery appear on fire:

  $ upower -i /org/freedesktop/UPower/devices/battery_olpc_battery
  ...
      temperature:         236.9 degrees C

Tested on OLPC XO-1 and OLPC XO-1.75 laptops.

[1] include/linux/power_supply.h
[2] Documentation/power/power_supply_class.txt

Fixes: fb972873a767 ("[BATTERY] One Laptop Per Child power/battery driver")
Cc: stable@vger.kernel.org
Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/power/olpc_battery.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/power/olpc_battery.c
+++ b/drivers/power/olpc_battery.c
@@ -427,14 +427,14 @@ static int olpc_bat_get_property(struct
 		if (ret)
 			return ret;
 
-		val->intval = (s16)be16_to_cpu(ec_word) * 100 / 256;
+		val->intval = (s16)be16_to_cpu(ec_word) * 10 / 256;
 		break;
 	case POWER_SUPPLY_PROP_TEMP_AMBIENT:
 		ret = olpc_ec_cmd(EC_AMB_TEMP, NULL, 0, (void *)&ec_word, 2);
 		if (ret)
 			return ret;
 
-		val->intval = (int)be16_to_cpu(ec_word) * 100 / 256;
+		val->intval = (int)be16_to_cpu(ec_word) * 10 / 256;
 		break;
 	case POWER_SUPPLY_PROP_CHARGE_COUNTER:
 		ret = olpc_ec_cmd(EC_BAT_ACR, NULL, 0, (void *)&ec_word, 2);