From: Angelo Compagnucci <angelo.compagnucci@gmail.com> [ Upstream commit a139ffa40f0c24b753838b8ef3dcf6ad10eb7854 ] Reading from the chip should be unlocked on error path else the lock could never being released. Fixes: 07914c84ba30 ("iio: adc: Add driver for Microchip MCP3422/3/4 high resolution ADC") Fixes: 3f1093d83d71 ("iio: adc: mcp3422: fix locking scope") Acked-by: Jonathan Cameron <jonathan.cameron@huawei.com> Signed-off-by: Angelo Compagnucci <angelo.compagnucci@gmail.com> Link: https://lore.kernel.org/r/20200901093218.1500845-1-angelo.compagnucci@gmail.... Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/iio/adc/mcp3422.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/iio/adc/mcp3422.c b/drivers/iio/adc/mcp3422.c index fd1496c9c3fb..4ee4ca35c255 100644 --- a/drivers/iio/adc/mcp3422.c +++ b/drivers/iio/adc/mcp3422.c @@ -146,8 +146,10 @@ static int mcp3422_read_channel(struct mcp3422 *adc, config &= ~MCP3422_PGA_MASK; config |= MCP3422_PGA_VALUE(adc->pga[req_channel]); ret = mcp3422_update_config(adc, config); - if (ret < 0) + if (ret < 0) { + mutex_unlock(&adc->lock); return ret; + } msleep(mcp3422_read_times[MCP3422_SAMPLE_RATE(adc->config)]); } -- 2.25.1