Re: [PATCH] iio: adc: ad7791: fix IRQ flags

[Jonathan Cameron <jic23@kernel.org>]

On Mon, 06 Feb 2023 12:13:50 +0100
Nuno Sá <noname.nuno@gmail.com> wrote:

> On Mon, 2023-01-30 at 10:01 +0100, Nuno Sá wrote:
> > On Sat, 2023-01-21 at 16:58 +0000, Jonathan Cameron wrote:  
> > > On Fri, 20 Jan 2023 13:46:45 +0100
> > > Nuno Sá <nuno.sa@analog.com> wrote:
> > >   
> > > > The interrupt is triggered on the falling edge rather than being
> > > > a
> > > > level
> > > > low interrupt.
> > > > 
> > > > Fixes: da4d3d6bb9f6 ("iio: adc: ad-sigma-delta: Allow custom IRQ
> > > > flags")
> > > > Signed-off-by: Nuno Sá <nuno.sa@analog.com>  
> > > 
> > > What are the symptoms of this?  Given the ad_sigma_delta.c irq
> > > handler
> > > disables the interrupt until after the data read is done (at which
> > > point the
> > > level is presumably high again), I don't immediately see why the
> > > change
> > > here has any impact - either we trigger on the fall, or on the fact
> > > it
> > > has become low..
> > > 
> > >   
> > 
> > Honestly I did not checked this in any HW. This was just by
> > inspecting
> > the datasheet and confirming that the LOW IRQ is not coherent with
> > what
> > we have in other sigma delta ADCs.
> > 
> > However, after some git blaming, I found this [1] which shows that
> > this
> > might be an issue...
> > 
> > Hmm, maybe makes sense to add a link to the bellow patch in the
> > commit
> > description...
> >  
> > [1]:
> > https://lore.kernel.org/linux-iio/20200113102653.20900-3-alexandru.tachici@analog.com
> > /
> > 
> > - Nuno Sá  
> 
> Hi Jonathan,
> 
> Anything that I should do in this one? As I did not tested it, it might
> not be a real issue but I still think the patch is good even though it
> might not deserve a Fixes tag...
> 
> - Nuno Sá

Applied to the fixes-togreg rbanch of iio.git.  I left the fixes tag
but just to be awkward didn't mark it for stable (it'll get picked up anyway
probably but I didn't want to imply there was any rush in doing so ;)

Thanks,

Jonathan