/**
* amdgpu_dm_set_regamma_lut: Set regamma lut for the given CRTC.
* @crtc: amdgpu_dm crtc state
*
* Update the underlying dc_stream_state's output transfer function (OTF) in
* preparation for hardware commit. If no lut is specified by user, we default
* to SRGB.
*
* RETURNS:
* 0 on success, -ENOMEM if memory cannot be allocated to calculate the OTF.
*/
int amdgpu_dm_set_regamma_lut(struct dm_crtc_state *crtc)
{
struct drm_property_blob *blob = crtc->base.gamma_lut;
struct dc_stream_state *stream = crtc->stream;
struct drm_color_lut *lut;
uint32_t lut_size;
struct dc_gamma *gamma;
enum dc_transfer_func_type old_type = stream->out_transfer_func->type;
bool ret;
if (!blob) {
/* By default, use the SRGB predefined curve.*/
stream->out_transfer_func->type = TF_TYPE_PREDEFINED;
stream->out_transfer_func->tf = TRANSFER_FUNCTION_SRGB;
return 0;
}
lut = (struct drm_color_lut *)blob->data;
lut_size = blob->length / sizeof(struct drm_color_lut);
gamma = dc_create_gamma();
if (!gamma)
return -ENOMEM;
gamma->num_entries = lut_size;
if (gamma->num_entries == MAX_COLOR_LEGACY_LUT_ENTRIES)
gamma->type = GAMMA_RGB_256;
else if (gamma->num_entries == MAX_COLOR_LUT_ENTRIES)
gamma->type = GAMMA_CS_TFM_1D;
else {
/* Invalid lut size */
dc_gamma_release(&gamma);
return -EINVAL;
}
/* Convert drm_lut into dc_gamma */
__drm_lut_to_dc_gamma(lut, gamma, gamma->type == GAMMA_RGB_256);
/* Call color module to translate into something DC understands. Namely
* a transfer function.
*/
stream->out_transfer_func->type = TF_TYPE_DISTRIBUTED_POINTS;
ret = mod_color_calculate_regamma_params(stream->out_transfer_func,
gamma, true);
dc_gamma_release(&gamma);
if (!ret) {
stream->out_transfer_func->type = old_type;
DRM_ERROR("Out of memory when calculating regamma params\n");
return -ENOMEM;
}
return 0;
}
/*******************************************************************************
* Private functions
******************************************************************************/
static void construct(struct dc_context *ctx, struct dc_plane_state *plane_state)
{
plane_state->ctx = ctx;
plane_state->gamma_correction = dc_create_gamma();
plane_state->gamma_correction->is_identity = true;
plane_state->in_transfer_func = dc_create_transfer_func();
plane_state->in_transfer_func->type = TF_TYPE_BYPASS;
plane_state->in_transfer_func->ctx = ctx;
}
