Re: [PATCH v5] iio: adc: ad_sigma_delta: Fix IRQ issue by setting IRQ_DISABLE_UNLAZY flag

[Masahiro Honda]

On Sun, May 21, 2023 at 12:21 AM Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>
> On Thu, 18 May 2023 20:08:16 +0900
> Masahiro Honda <honda@xxxxxxxxxxxxx> wrote:
>
> > The Sigma-Delta ADCs supported by this driver can use SDO as an interrupt
> > line to indicate the completion of a conversion. However, some devices
> > cannot properly detect the completion of a conversion by an interrupt.
> > This is for the reason mentioned in the following commit.
> >
> > commit e9849777d0e2 ("genirq: Add flag to force mask in
> >                       disable_irq[_nosync]()")
> >
> > A read operation is performed by an extra interrupt before the completion
> > of a conversion. At this time, the value read from the ADC data register
> > is the same as the previous conversion result. This patch fixes the issue
> > by setting IRQ_DISABLE_UNLAZY flag.
> >
> > Fixes: 0c6ef985a1f ("iio: adc: ad7791: fix IRQ flags")
> > Fixes: 1a913270e57 ("iio: adc: ad7793: Fix IRQ flag")
> > Fixes: e081102f307 ("iio: adc: ad7780: Fix IRQ flag")
> > Fixes: 89a86da5cb8 ("iio: adc: ad7192: Add IRQ flag")
> > Fixes: 79ef91493f5 ("iio: adc: ad7124: Set IRQ type to falling")
> All the fixes tags have 11 chars of the hash, needs to be 12. I fixed that up whilst applying
Sorry. I made mistakes. Thanks for fixing them.

Regards,

Masahiro

> Applied to the fixes-togreg branch of iio.git and marked for stable.
>
> Thanks,
>
> Jonathan
>
> > Signed-off-by: Masahiro Honda <honda@xxxxxxxxxxxxx>
> > ---
> > v5:
> >  - Fix the patch title.
> >  - Add fixes tags.
> >  - Add information about behavior to the commit message.
> > v4: https://lore.kernel.org/linux-iio/20230502102930.773-1-honda@xxxxxxxxxxxxx/
> >  - Remove the callback.
> > v3: https://lore.kernel.org/linux-iio/20230420102316.757-1-honda@xxxxxxxxxxxxx/
> >  - Remove the Kconfig option.
> > v2: https://lore.kernel.org/linux-iio/20230414102744.150-1-honda@xxxxxxxxxxxxx/
> >  - Rework commit message.
> >  - Add a new entry in the Kconfig.
> >  - Call irq_clear_status_flags(irq, IRQ_DISABLE_UNLAZY) when freeing the IRQ.
> > v1: https://lore.kernel.org/linux-iio/20230306044737.862-1-honda@xxxxxxxxxxxxx/
> >
> >  drivers/iio/adc/ad_sigma_delta.c | 4 ++++
> >  1 file changed, 4 insertions(+)
> >
> > diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c
> > index d8570f62078..7e219287074 100644
> > --- a/drivers/iio/adc/ad_sigma_delta.c
> > +++ b/drivers/iio/adc/ad_sigma_delta.c
> > @@ -584,6 +584,10 @@ static int devm_ad_sd_probe_trigger(struct device *dev, struct iio_dev *indio_de
> >       init_completion(&sigma_delta->completion);
> >
> >       sigma_delta->irq_dis = true;
> > +
> > +     /* the IRQ core clears IRQ_DISABLE_UNLAZY flag when freeing an IRQ */
> > +     irq_set_status_flags(sigma_delta->spi->irq, IRQ_DISABLE_UNLAZY);
> > +
> >       ret = devm_request_irq(dev, sigma_delta->spi->irq,
> >                              ad_sd_data_rdy_trig_poll,
> >                              sigma_delta->info->irq_flags | IRQF_NO_AUTOEN,
>