From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nicolin Chen , Guenter Roeck , Sasha Levin Subject: [PATCH 4.14 27/89] hwmon: (ina2xx) Fix current value calculation Date: Fri, 14 Dec 2018 12:59:40 +0100 Message-Id: <20181214115731.036940084@linuxfoundation.org> In-Reply-To: <20181214115729.658859279@linuxfoundation.org> References: <20181214115729.658859279@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 4.14-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit 38cd989ee38c16388cde89db5b734f9d55b905f9 ] The current register (04h) has a sign bit at MSB. The comments for this calculation also mention that it's a signed register. However, the regval is unsigned type so result of calculation turns out to be an incorrect value when current is negative. This patch simply fixes this by adding a casting to s16. Fixes: 5d389b125186c ("hwmon: (ina2xx) Make calibration register value fixed") Signed-off-by: Nicolin Chen Signed-off-by: Guenter Roeck Signed-off-by: Sasha Levin --- drivers/hwmon/ina2xx.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/hwmon/ina2xx.c b/drivers/hwmon/ina2xx.c index c2252cf452f5..07ee19573b3f 100644 --- a/drivers/hwmon/ina2xx.c +++ b/drivers/hwmon/ina2xx.c @@ -274,7 +274,7 @@ static int ina2xx_get_value(struct ina2xx_data *data, u8 reg, break; case INA2XX_CURRENT: /* signed register, result in mA */ - val = regval * data->current_lsb_uA; + val = (s16)regval * data->current_lsb_uA; val = DIV_ROUND_CLOSEST(val, 1000); break; case INA2XX_CALIBRATION: -- 2.19.1