On Sun, 11 Nov 2018 23:00:18 +0800
Baolin Wang <baolin.wang@xxxxxxxxxx> wrote:
> Hi Jonathan,
>
> On 11 November 2018 at 20:40, Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> > On Fri, 9 Nov 2018 11:25:31 +0800
> > Baolin Wang <baolin.wang@xxxxxxxxxx> wrote:
> >
> >> From: Freeman Liu <freeman.liu@xxxxxxxxxx>
> >>
> >> Sometimes the ADC controller met some problems, and it will not complete
> >> the data conversion, that will can not wake up the read process any more
> >> to block users. So we should add one maximum conversion time to avoid
> >> this issue.
> >>
> >> Signed-off-by: Freeman Liu <freeman.liu@xxxxxxxxxx>
> >> Signed-off-by: Baolin Wang <baolin.wang@xxxxxxxxxx>
> > Hi.
> >
> > Patch looks good, but sounds like this is a fix so could I have a fixes
> > tag and a patch title that makes that clear?
> >
> > I think we will want this one back ported to stable by the sound of it.
> >
> > If it is just a theoretical issue then perhaps we don't need to bother.
>
> Thanks for your review. This patch is not one bug fix, just make the
> code more robust in case of some bad cases. So I think we do not need
> the stable tag.
Thanks.
Applied to the togreg branch of iio.git and pushed out as testing for
the autobuilders to play with it.
Jonathan
>
> >
> > Thanks,
> >
> > Jonathan
> >
> >> ---
> >> drivers/iio/adc/sc27xx_adc.c | 12 +++++++++++-
> >> 1 file changed, 11 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/iio/adc/sc27xx_adc.c b/drivers/iio/adc/sc27xx_adc.c
> >> index 7940b23..f7f7a189 100644
> >> --- a/drivers/iio/adc/sc27xx_adc.c
> >> +++ b/drivers/iio/adc/sc27xx_adc.c
> >> @@ -52,6 +52,9 @@
> >> /* Timeout (ms) for the trylock of hardware spinlocks */
> >> #define SC27XX_ADC_HWLOCK_TIMEOUT 5000
> >>
> >> +/* Timeout (ms) for ADC data conversion according to ADC datasheet */
> >> +#define SC27XX_ADC_RDY_TIMEOUT 100
> >> +
> >> /* Maximum ADC channel number */
> >> #define SC27XX_ADC_CHANNEL_MAX 32
> >>
> >> @@ -223,7 +226,14 @@ static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
> >> if (ret)
> >> goto disable_adc;
> >>
> >> - wait_for_completion(&data->completion);
> >> + ret = wait_for_completion_timeout(&data->completion,
> >> + msecs_to_jiffies(SC27XX_ADC_RDY_TIMEOUT));
> >> + if (!ret) {
> >> + dev_err(data->dev, "read ADC data timeout\n");
> >> + ret = -ETIMEDOUT;
> >> + } else {
> >> + ret = 0;
> >> + }
> >>
> >> disable_adc:
> >> regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
> >
>
>
>
