| From 7524ad369768ab6c2770b8018c90b209efadb50c Mon Sep 17 00:00:00 2001 |
| From: Sasha Levin <sashal@kernel.org> |
| Date: Tue, 1 Sep 2020 11:32:18 +0200 |
| Subject: iio: adc: mcp3422: fix locking on error path |
| |
| 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.com |
| 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 ea24d7c58b127..4d03b1f265d9c 100644 |
| --- a/drivers/iio/adc/mcp3422.c |
| +++ b/drivers/iio/adc/mcp3422.c |
| @@ -144,8 +144,10 @@ 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 |
| |
