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 d86c0b5d80a3d..c717981c8fb03 100644 --- a/drivers/iio/adc/mcp3422.c +++ b/drivers/iio/adc/mcp3422.c @@ -145,8 +145,10 @@ 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)]); }