[PATCH 2/5] iio: stmpe-adc: Reinit completion struct on begin conversion

From: Philippe Schenker
Date: Tue May 07 2019 - 10:37:29 EST


From: Philippe Schenker <philippe.schenker@xxxxxxxxxxx>

In some cases, the wait_completion got interrupted. This caused the
error-handling to mutex_unlock the function. The before turned on
interrupt then got called anyway. In the ISR then completion() was
called causing wrong adc-values returned in a following adc-readout.

Reinitialise completion struct to make sure the counter is zero
when beginning a new adc-conversion.

Signed-off-by: Philippe Schenker <philippe.schenker@xxxxxxxxxxx>
---

drivers/iio/adc/stmpe-adc.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/iio/adc/stmpe-adc.c b/drivers/iio/adc/stmpe-adc.c
index 9ec338ba3440..b3872eb37293 100644
--- a/drivers/iio/adc/stmpe-adc.c
+++ b/drivers/iio/adc/stmpe-adc.c
@@ -65,6 +65,8 @@ static int stmpe_read_voltage(struct stmpe_adc *info,

mutex_lock(&info->lock);

+ reinit_completion(&info->completion);
+
info->channel = (u8)chan->channel;

if (info->channel > STMPE_ADC_LAST_NR) {
@@ -105,6 +107,8 @@ static int stmpe_read_temp(struct stmpe_adc *info,

mutex_lock(&info->lock);

+ reinit_completion(&info->completion);
+
info->channel = (u8)chan->channel;

if (info->channel != STMPE_TEMP_CHANNEL) {
--
2.21.0