On Mon, 2022-04-11 at 10:30 +0000, Miaoqian Lin wrote: > wait_for_completion_timeout() returns unsigned long not long. > it returns 0 if timed out, and positive if completed. > The check for <= 0 is ambiguous and should be == 0 here > indicating timeout which is the only error case Hello and thanks for your fix. Any specific reason you didn't apply this also in function stmpe_read_temp? Philippe > > Fixes: e813dde6f833 ("iio: stmpe-adc: Use > wait_for_completion_timeout") > Signed-off-by: Miaoqian Lin <linmq006@xxxxxxxxx> > --- > drivers/iio/adc/stmpe-adc.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/drivers/iio/adc/stmpe-adc.c b/drivers/iio/adc/stmpe-adc.c > index d2d405388499..d475d1c17bfc 100644 > --- a/drivers/iio/adc/stmpe-adc.c > +++ b/drivers/iio/adc/stmpe-adc.c > @@ -61,7 +61,7 @@ struct stmpe_adc { > static int stmpe_read_voltage(struct stmpe_adc *info, > struct iio_chan_spec const *chan, int *val) > { > - long ret; > + unsigned long ret; > > mutex_lock(&info->lock); > > @@ -79,7 +79,7 @@ static int stmpe_read_voltage(struct stmpe_adc > *info, > > ret = wait_for_completion_timeout(&info->completion, > STMPE_ADC_TIMEOUT); > > - if (ret <= 0) { > + if (ret == 0) { > stmpe_reg_write(info->stmpe, STMPE_REG_ADC_INT_STA, > STMPE_ADC_CH(info->channel)); > mutex_unlock(&info->lock);