[PATCH] drm: Use EOPNOTSUPP, not ENOTSUPP

[Daniel Vetter]

On Wed, Sep 04, 2019 at 10:05:09PM +0200, Daniel Vetter wrote:
> On Wed, Sep 4, 2019 at 9:58 PM Souza, Jose <jose.souza at intel.com> wrote:
> >
> > On Wed, 2019-09-04 at 16:39 +0200, Daniel Vetter wrote:
> > > - it's what we recommend in our docs:
> > >
> > > https://dri.freedesktop.org/docs/drm/gpu/drm-uapi.html#recommended-ioctl-return-values
> > >
> > > - it's the overwhelmingly used error code for "operation not
> > >   supported", at least in drm core (slightly less so in drivers):
> > >
> > > $ git grep EOPNOTSUP -- drivers/gpu/drm/*c | wc -l
> > > 83
> > > $ git grep ENOTSUP -- drivers/gpu/drm/*c | wc -l
> > > 5
> > >
> > > - include/linux/errno.h makes it fairly clear that these are for
> > > nfsv3
> > >   (plus they also have error codes above 512, which is the block with
> > >   some special behaviour ...)
> > >
> > > /* Defined for the NFSv3 protocol */
> > >
> > > If the above isn't reflecting current practice, then I guess we
> > > should
> > > at least update the docs.
> >
> > Hopefully this will not break any userspace
> 
> None of the functions in drm_edid.c affected by this reach userspace,
> it's all driver internal.
> 
> Same for the mipi function, that error code should be handled by
> drivers. Drivers are supposed to remap "the hw is on fire" to EIO when
> reporting up to userspace, but I think if a driver sees this it would
> be a driver bug.
> 
> So no way this goes out to userspace, I really only did this to have
> the drm core/helpers be 100% consistent with our documented
> recommendations here.
> 
> I'll summarize the above in the commit message when I merge the patch.
> 
> > Reviewed-by: José Roberto de Souza <jose.souza at intel.com>
> 
> Thanks, Daniel

Applied now.
-Daniel

> 
> >
> > >
> > > Cc: José Roberto de Souza <jose.souza at intel.com>
> > > Cc: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
> > > Cc: Maxime Ripard <mripard at kernel.org>
> > > Cc: Sean Paul <sean at poorly.run>
> > > Cc: Alex Deucher <alexander.deucher at amd.com>
> > > Cc: Andres Rodriguez <andresx7 at gmail.com>
> > > Cc: Noralf Trønnes <noralf at tronnes.org>
> > > Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
> > > ---
> > >  drivers/gpu/drm/drm_edid.c     | 6 +++---
> > >  drivers/gpu/drm/drm_mipi_dbi.c | 2 +-
> > >  2 files changed, 4 insertions(+), 4 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/drm_edid.c b/drivers/gpu/drm/drm_edid.c
> > > index 82a4ceed3fcf..12c783f4d956 100644
> > > --- a/drivers/gpu/drm/drm_edid.c
> > > +++ b/drivers/gpu/drm/drm_edid.c
> > > @@ -3719,7 +3719,7 @@ cea_db_offsets(const u8 *cea, int *start, int
> > > *end)
> > >               if (*end < 4 || *end > 127)
> > >                       return -ERANGE;
> > >       } else {
> > > -             return -ENOTSUPP;
> > > +             return -EOPNOTSUPP;
> > >       }
> > >
> > >       return 0;
> > > @@ -4188,7 +4188,7 @@ int drm_edid_to_sad(struct edid *edid, struct
> > > cea_sad **sads)
> > >
> > >       if (cea_revision(cea) < 3) {
> > >               DRM_DEBUG_KMS("SAD: wrong CEA revision\n");
> > > -             return -ENOTSUPP;
> > > +             return -EOPNOTSUPP;
> > >       }
> > >
> > >       if (cea_db_offsets(cea, &start, &end)) {
> > > @@ -4249,7 +4249,7 @@ int drm_edid_to_speaker_allocation(struct edid
> > > *edid, u8 **sadb)
> > >
> > >       if (cea_revision(cea) < 3) {
> > >               DRM_DEBUG_KMS("SAD: wrong CEA revision\n");
> > > -             return -ENOTSUPP;
> > > +             return -EOPNOTSUPP;
> > >       }
> > >
> > >       if (cea_db_offsets(cea, &start, &end)) {
> > > diff --git a/drivers/gpu/drm/drm_mipi_dbi.c
> > > b/drivers/gpu/drm/drm_mipi_dbi.c
> > > index c4ee2709a6f3..f8154316a3b0 100644
> > > --- a/drivers/gpu/drm/drm_mipi_dbi.c
> > > +++ b/drivers/gpu/drm/drm_mipi_dbi.c
> > > @@ -955,7 +955,7 @@ static int mipi_dbi_typec1_command(struct
> > > mipi_dbi *dbi, u8 *cmd,
> > >       int ret;
> > >
> > >       if (mipi_dbi_command_is_read(dbi, *cmd))
> > > -             return -ENOTSUPP;
> > > +             return -EOPNOTSUPP;
> > >
> > >       MIPI_DBI_DEBUG_COMMAND(*cmd, parameters, num);
> > >
> 
> 
> 
> -- 
> Daniel Vetter
> Software Engineer, Intel Corporation
> +41 (0) 79 365 57 48 - http://blog.ffwll.ch

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch