[v3 6/7] drm: Add Client Cap for advance gamma mode

[Sharma, Shashank]

> -----Original Message-----
> From: Lankhorst, Maarten
> Sent: Monday, April 15, 2019 4:28 PM
> To: Shankar, Uma <uma.shankar at intel.com>; intel-gfx at lists.freedesktop.org; dri-
> devel at lists.freedesktop.org
> Cc: Syrjala, Ville <ville.syrjala at intel.com>; emil.l.velikov at gmail.com;
> sam at ravnborg.org; Roper, Matthew D <matthew.d.roper at intel.com>;
> seanpaul at chromium.org; brian.starkey at arm.com; dcastagna at chromium.org;
> Sharma, Shashank <shashank.sharma at intel.com>
> Subject: Re: [v3 6/7] drm: Add Client Cap for advance gamma mode
> 
> fre 2019-04-12 klockan 15:51 +0530 skrev Uma Shankar:
> > Introduced a client cap for advance cap mode
> > capability. Userspace should set this to get
> > to be able to use the new gamma_mode property.
> >
> > If this is not set, driver will work in legacy
> > mode.
> >
> > Suggested-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Signed-off-by: Uma Shankar <uma.shankar at intel.com>
> 
> Nack, this doesn't seem like a sensible idea. We already guard it
> behind the gamma mode property. Userspace shouldn't set the gamma mode
> to a value it doesn't understand.
> 
> ~Maarten

Hey Maarten, 
In that case, what do you suggest should be the right way to do this ? 

@Ville, any comments here ? 

Regards
Shashank
> 
> >  drivers/gpu/drm/drm_atomic_uapi.c | 3 +++
> >  drivers/gpu/drm/drm_ioctl.c       | 5 +++++
> >  include/drm/drm_atomic.h          | 1 +
> >  include/drm/drm_crtc.h            | 7 +++++++
> >  include/drm/drm_file.h            | 8 ++++++++
> >  include/uapi/drm/drm.h            | 2 ++
> >  6 files changed, 26 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/drm_atomic_uapi.c
> > b/drivers/gpu/drm/drm_atomic_uapi.c
> > index d85e0c9..590c87a 100644
> > --- a/drivers/gpu/drm/drm_atomic_uapi.c
> > +++ b/drivers/gpu/drm/drm_atomic_uapi.c
> > @@ -974,6 +974,8 @@ int drm_atomic_set_property(struct
> > drm_atomic_state *state,
> >  			break;
> >  		}
> >
> > +		crtc_state->advance_gamma_mode_active =
> > +					state-
> > >advance_gamma_mode_active;
> >  		ret = drm_atomic_crtc_set_property(crtc,
> >  				crtc_state, prop, prop_value);
> >  		break;
> > @@ -1297,6 +1299,7 @@ int drm_mode_atomic_ioctl(struct drm_device
> > *dev,
> >  	drm_modeset_acquire_init(&ctx,
> > DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
> >  	state->acquire_ctx = &ctx;
> >  	state->allow_modeset = !!(arg->flags &
> > DRM_MODE_ATOMIC_ALLOW_MODESET);
> > +	state->advance_gamma_mode_active = file_priv-
> > >advance_gamma_mode_active;
> >
> >  retry:
> >  	copied_objs = 0;
> > diff --git a/drivers/gpu/drm/drm_ioctl.c
> > b/drivers/gpu/drm/drm_ioctl.c
> > index d337f16..e593a4c 100644
> > --- a/drivers/gpu/drm/drm_ioctl.c
> > +++ b/drivers/gpu/drm/drm_ioctl.c
> > @@ -348,6 +348,11 @@ static int drm_getcap(struct drm_device *dev,
> > void *data, struct drm_file *file_
> >  			return -EINVAL;
> >  		file_priv->writeback_connectors = req->value;
> >  		break;
> > +	case DRM_CLIENT_CAP_ADVANCE_GAMMA_MODES:
> > +		if (req->value > 1)
> > +			return -EINVAL;
> > +		file_priv->advance_gamma_mode_active = req->value;
> > +		break;
> >  	default:
> >  		return -EINVAL;
> >  	}
> > diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h
> > index 824a5ed..02c1a68 100644
> > --- a/include/drm/drm_atomic.h
> > +++ b/include/drm/drm_atomic.h
> > @@ -338,6 +338,7 @@ struct drm_atomic_state {
> >  	 * states.
> >  	 */
> >  	bool duplicated : 1;
> > +	bool advance_gamma_mode_active : 1;
> >  	struct __drm_planes_state *planes;
> >  	struct __drm_crtcs_state *crtcs;
> >  	int num_connector;
> > diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> > index f789359..f11dc25 100644
> > --- a/include/drm/drm_crtc.h
> > +++ b/include/drm/drm_crtc.h
> > @@ -170,6 +170,11 @@ struct drm_crtc_state {
> >  	bool color_mgmt_changed : 1;
> >
> >  	/**
> > +	 * This is to indicate advance gamma mode support
> > +	 */
> > +	bool advance_gamma_mode_active : 1;
> > +
> > +	/**
> >  	 * @no_vblank:
> >  	 *
> >  	 * Reflects the ability of a CRTC to send VBLANK events.
> > This state
> > @@ -952,6 +957,8 @@ struct drm_crtc {
> >  	 */
> >  	bool enabled;
> >
> > +	bool advance_gamma_mode_active : 1;
> > +
> >  	/**
> >  	 * @mode:
> >  	 *
> > diff --git a/include/drm/drm_file.h b/include/drm/drm_file.h
> > index 6710b61..b5aa24e 100644
> > --- a/include/drm/drm_file.h
> > +++ b/include/drm/drm_file.h
> > @@ -201,6 +201,14 @@ struct drm_file {
> >  	bool writeback_connectors;
> >
> >  	/**
> > +	 * This is to enable advance gamma modes using
> > +	 * gamma_mode property
> > +	 *
> > +	 * True if client understands advance gamma
> > +	 */
> > +	bool advance_gamma_mode_active : 1;
> > +
> > +	/**
> >  	 * @is_master:
> >  	 *
> >  	 * This client is the creator of @master. Protected by
> > struct
> > diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h
> > index 236b01a..abef966 100644
> > --- a/include/uapi/drm/drm.h
> > +++ b/include/uapi/drm/drm.h
> > @@ -696,6 +696,8 @@ struct drm_get_cap {
> >   */
> >  #define DRM_CLIENT_CAP_WRITEBACK_CONNECTORS	5
> >
> > +#define DRM_CLIENT_CAP_ADVANCE_GAMMA_MODES	6
> > +
> >  /** DRM_IOCTL_SET_CLIENT_CAP ioctl argument type */
> >  struct drm_set_client_cap {
> >  	__u64 capability;