Re: [PATCH] drm: Add rotation_property to mode_config and creating it

[Daniel Vetter <daniel@ffwll.ch>]

On Mon, Jul 28, 2014 at 06:29:41PM +0300, Ville Syrjälä wrote:
> On Tue, Jul 15, 2014 at 05:43:37PM +0530, sonika.jindal@intel.com wrote:
> > From: Sonika Jindal <sonika.jindal@intel.com>
> > 
> > v2: Adding creation of rotation_property here.
> > 
> > Signed-off-by: Sonika Jindal <sonika.jindal@intel.com>
> > ---
> >  drivers/gpu/drm/drm_crtc.c |    3 ++-
> >  include/drm/drm_crtc.h     |    1 +
> >  2 files changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> > index 787631e..49c0747 100644
> > --- a/drivers/gpu/drm/drm_crtc.c
> > +++ b/drivers/gpu/drm/drm_crtc.c
> > @@ -1299,7 +1299,8 @@ static int drm_mode_create_standard_plane_properties(struct drm_device *dev)
> >  					"type", drm_plane_type_enum_list,
> >  					ARRAY_SIZE(drm_plane_type_enum_list));
> >  	dev->mode_config.plane_type_property = type;
> > -
> > +	dev->mode_config.rotation_property = drm_mode_create_rotation_property(dev,
> > +			BIT(DRM_ROTATE_0) | BIT(DRM_ROTATE_180));
> 
> This might not make sense for other (!i915) hardware. And that's the
> reason why I had the driver create the property in the first place.
> 
> I think Daniel was thinking that we might want to expose all the bits
> regardless of what the hardware supports, but I don't like that idea.
> There are other properties (eg. alpha blending, csc stuff, etc.) that
> have the same problem of hardware supporting only a (potentially small)
> subset of the possible values. I'd rather we didn't make life harder
> for userspace when the kernel can already report that certain values
> will never work.

Well I'd like the property to be in some generic place so that fbcon can
unroate and that with the atomic stuff we can have rotation support in the
core structures. Which should help with argument checking.

But for rotation I don't think we should set it up in generic code, but in
i915. So the place where we keep it would be generic, the values would be
the sames, but the allowed set would differ depending upon platform or
driver.
-Daniel

> 
> >  	return 0;
> >  }
> >  
> > diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> > index ce6df4a..5545dd3 100644
> > --- a/include/drm/drm_crtc.h
> > +++ b/include/drm/drm_crtc.h
> > @@ -819,6 +819,7 @@ struct drm_mode_config {
> >  	struct drm_property *dpms_property;
> >  	struct drm_property *path_property;
> >  	struct drm_property *plane_type_property;
> > +	struct drm_property *rotation_property;
> >  
> >  	/* DVI-I properties */
> >  	struct drm_property *dvi_i_subconnector_property;
> > -- 
> > 1.7.10.4
> > 
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx@lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> -- 
> Ville Syrjälä
> Intel OTC
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch