From a139ffa40f0c24b753838b8ef3dcf6ad10eb7854 Mon Sep 17 00:00:00 2001 From: Angelo Compagnucci Date: Tue, 1 Sep 2020 11:32:18 +0200 Subject: [PATCH] iio: adc: mcp3422: fix locking on error path 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 Signed-off-by: Angelo Compagnucci Link: https://lore.kernel.org/r/20200901093218.1500845-1-angelo.compagnucci@gmail.com Signed-off-by: Greg Kroah-Hartman --- 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 219adac2384b..da353dcb1e9d 100644 --- a/drivers/iio/adc/mcp3422.c +++ b/drivers/iio/adc/mcp3422.c @@ -143,8 +143,10 @@ 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)]); }