The DRM core handles legacy gamma-set ioctl by setting GAMMA_LUT and clearing CTM and DEGAMMA_LUT.
This works fine on HW where we have either:
degamma -> ctm -> gamma -> out
or
ctm -> gamma -> out
However, if the HW has gamma table before ctm, the atomic property should be DEGAMMA_LUT, and thus we have:
degamma -> ctm -> out
This is fine for userspace which sets gamma table using the properties, as the userspace can check for the existence of gamma & degamma, but the legacy gamma-set ioctl does not work.
Change the DRM core to use DEGAMMA_LUT instead of GAMMA_LUT when the latter is unavailable.
Signed-off-by: Tomi Valkeinen tomi.valkeinen@ti.com --- drivers/gpu/drm/drm_color_mgmt.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/drm_color_mgmt.c b/drivers/gpu/drm/drm_color_mgmt.c index c4e4d59c4432..8733d9d95b82 100644 --- a/drivers/gpu/drm/drm_color_mgmt.c +++ b/drivers/gpu/drm/drm_color_mgmt.c @@ -238,6 +238,7 @@ EXPORT_SYMBOL(drm_mode_crtc_set_gamma_size); bool drm_crtc_supports_legacy_gamma(struct drm_crtc *crtc) { uint32_t gamma_id = crtc->dev->mode_config.gamma_lut_property->base.id; + uint32_t degamma_id = crtc->dev->mode_config.degamma_lut_property->base.id;
if (!crtc->gamma_size) return false; @@ -245,7 +246,8 @@ bool drm_crtc_supports_legacy_gamma(struct drm_crtc *crtc) if (crtc->funcs->gamma_set) return true;
- return !!drm_mode_obj_find_prop_id(&crtc->base, gamma_id); + return !!(drm_mode_obj_find_prop_id(&crtc->base, gamma_id) || + drm_mode_obj_find_prop_id(&crtc->base, degamma_id)); } EXPORT_SYMBOL(drm_crtc_supports_legacy_gamma);
@@ -256,18 +258,28 @@ EXPORT_SYMBOL(drm_crtc_supports_legacy_gamma); * @blob: property blob for the gamma ramp * * Set given gamma ramp to the crtc using GAMMA_LUT property and resetting - * DEGAMMA_LUT and CTM. + * DEGAMMA_LUT and CTM, or if GAMMA_LUT is not available, using DEGAMMA_LUT + * and resetting GAMMA_LUT and CTM. */ int drm_crtc_gamma_ramp_set(struct drm_atomic_state *state, struct drm_crtc *crtc, struct drm_property_blob *blob) { + uint32_t gamma_id = crtc->dev->mode_config.gamma_lut_property->base.id; + uint32_t degamma_id = crtc->dev->mode_config.degamma_lut_property->base.id; struct drm_crtc_state *crtc_state; struct drm_property_blob *gamma_blob; struct drm_property_blob *degamma_blob; bool replaced;
- gamma_blob = blob; - degamma_blob = NULL; + if (drm_mode_obj_find_prop_id(&crtc->base, gamma_id)) { + gamma_blob = blob; + degamma_blob = NULL; + } else if (drm_mode_obj_find_prop_id(&crtc->base, degamma_id)) { + gamma_blob = NULL; + degamma_blob = blob; + } else { + return -ENODEV; + }
crtc_state = drm_atomic_get_crtc_state(state, crtc); if (IS_ERR(crtc_state))