Re: [PATCH 19/20] drm: rcar-du: crtc: Register GAMMA_LUT properties

[Daniel Vetter]

On Fri, Jun 14, 2019 at 10:15:52AM +0200, Jacopo Mondi wrote:
> Hi Laurent,
>    thanks for review
> 
> On Fri, Jun 07, 2019 at 03:03:04PM +0300, Laurent Pinchart wrote:
> > Hi Jacopo,
> >
> > Thank you for the patch.
> >
> > On Thu, Jun 06, 2019 at 04:22:19PM +0200, Jacopo Mondi wrote:
> > > Enable the GAMMA_LUT KMS property using the framework helpers to
> > > register the proeprty and the associated gamma table size maximum size.
> > >
> > > Signed-off-by: Jacopo Mondi <jacopo+renesas@xxxxxxxxxx>
> > > ---
> > >  drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 3 +++
> > >  1 file changed, 3 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
> > > index e6d3df37c827..c920fb5dba65 100644
> > > --- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
> > > +++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
> > > @@ -1207,6 +1207,9 @@ int rcar_du_crtc_create(struct rcar_du_group *rgrp, unsigned int swindex,
> > >  	    rcdu->cmms[swindex]) {
> > >  		rcrtc->cmm = rcdu->cmms[swindex];
> > >  		rgrp->cmms_mask |= BIT(hwindex % 2);
> > > +
> > > +		drm_mode_crtc_set_gamma_size(crtc, CMM_GAMMA_LUT_SIZE);
> > > +		drm_crtc_enable_color_mgmt(crtc, 0, false, CMM_GAMMA_LUT_SIZE);
> >
> > This change looks good, but you also need to add support for legacy API.
> > According to the function's documentation,
> >
> >  * Drivers should use drm_atomic_helper_legacy_gamma_set() to implement the
> >  * legacy &drm_crtc_funcs.gamma_set callback.
> >
> 
> Drivers 'shuld' or drivers 'shall' ?
> Isn't this required only to support the 'legacy APIs' ? Do we want that?

You're calling drm_mode_crtc_set_gamma_size, which is only useful for the
legacy ioctls. should here = assuming your hw supports something that
legacy gamma ioctl can use. Feel free to patch up the docs.
-Daniel

> 
> Thanks
>    j
> 
> > >  	}
> > >
> > >  	drm_crtc_helper_add(crtc, &crtc_helper_funcs);
> > >
> >
> > --
> > Regards,
> >
> > Laurent Pinchart



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