From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Lechner Subject: [PATCH 2/2] power: supply: lego_ev3_battery: fix Vce offset Date: Fri, 20 Jul 2018 15:19:44 -0500 Message-ID: <20180720201944.20503-3-david@lechnology.com> References: <20180720201944.20503-1-david@lechnology.com> Return-path: In-Reply-To: <20180720201944.20503-1-david@lechnology.com> Sender: linux-kernel-owner@vger.kernel.org To: Sebastian Reichel Cc: David Lechner , linux-pm@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-pm@vger.kernel.org This fixes the value that accounts for the Vce of a transistor in the LEGO MINDSTORMS EV3 power supply driver. The old value (200mV) was the max value from the data sheet. After testing, the actual value has been found to be 50mV. By using 50mV we get a more accurate voltage indication. Signed-off-by: David Lechner --- drivers/power/supply/lego_ev3_battery.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/power/supply/lego_ev3_battery.c b/drivers/power/supply/lego_ev3_battery.c index 6e3b3e384172..1ae3710909b7 100644 --- a/drivers/power/supply/lego_ev3_battery.c +++ b/drivers/power/supply/lego_ev3_battery.c @@ -52,7 +52,7 @@ static int lego_ev3_battery_get_property(struct power_supply *psy, return ret; val->intval *= 2000; - val->intval += 200000; + val->intval += 50000; /* plus adjust for shunt resistor drop */ ret = iio_read_channel_processed(batt->iio_i, &val2); -- 2.17.1