+CC Alexandru Ardelean On Mon, 3 May 2021 12:06:15 +0100 Jonathan Cameron <jic23@xxxxxxxxxx> wrote: > On Wed, 28 Apr 2021 15:33:21 +0000 > "Sa, Nuno" <Nuno.Sa@xxxxxxxxxx> wrote: > > > > From: Sa, Nuno <Nuno.Sa@xxxxxxxxxx> > > > Sent: Wednesday, April 28, 2021 5:31 PM > > > To: Paul Cercueil <paul@xxxxxxxxxxxxxxx>; Jonathan Cameron > > > <jic23@xxxxxxxxxx>; Lars-Peter Clausen <lars@xxxxxxxxxx>; Peter > > > Meerwald-Stadler <pmeerw@xxxxxxxxxx> > > > Cc: linux-iio@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx > > > Subject: RE: [PATCH] tools/iio: iio_event_monitor: Fix ioctl error check > > > > > > > > > > From: Paul Cercueil <paul@xxxxxxxxxxxxxxx> > > > > Sent: Wednesday, April 28, 2021 5:08 PM > > > > To: Jonathan Cameron <jic23@xxxxxxxxxx>; Lars-Peter Clausen > > > > <lars@xxxxxxxxxx>; Peter Meerwald-Stadler > > > > <pmeerw@xxxxxxxxxx> > > > > Cc: linux-iio@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Paul > > > > Cercueil <paul@xxxxxxxxxxxxxxx> > > > > Subject: [PATCH] tools/iio: iio_event_monitor: Fix ioctl error check > > > > > > > > > > > > The ioctrl() call will return errno=EINVAL if the device does not > > > > support the events interface, and not ENODEV. > > > > > > > > Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx> > > > > > > Reviewed-by: Nuno Sa <nuno.sa@xxxxxxxxxx> > > > > > > > I guess this should have a Fixes: tag... > > So, I did a bit of detective work on this one. Seems this change in error > code was actually introduced as a side effect of Alex's recent rework of > the IOCTLs. Prior to that we returned -ENODEV for this case and now > we do indeed return EINVAL. > > So we may need to figure out how to fix that, or decide that such is life > and modify this code to give the right error message as done in this patch... > > Linus / Alex, thoughts? It's always been a bit messy because we also > return -ENODEV in the path where the ioctl hits a driver that is going away > so it hasn't uniquely identified a lack of support for a long time, even > if that is by far the most likely reason for this return code. > > Jonathan > > > > > > - Nuno Sá >
