From: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx> [ Upstream commit d053fbc449c47517b1f6516dbce2f917f2a9f51d ] According to the `/* bpc 8 */` comment below only values for a bits_per_component of 8 are currently hardcoded in place. This is further confirmed by downstream sources [1] containing different constants for other BPC values (and different initial_offset too, with an extra dependency on bits_per_pixel). Prevent future mishaps by explicitly disallowing any other bits_per_component value until the right parameters are put in place and tested. [1]: https://git.codelinaro.org/clo/la/platform/vendor/opensource/display-drivers/-/blob/DISPLAY.LA.2.0.r1-08000-WAIPIO.0/msm/sde_dsc_helper.c#L110-139 Fixes: b9080324d6ca ("drm/msm/dsi: add support for dsc data") Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Signed-off-by: Marijn Suijten <marijn.suijten@xxxxxxxxxxxxxx> Patchwork: https://patchwork.freedesktop.org/patch/508942/ Link: https://lore.kernel.org/r/20221026182824.876933-9-marijn.suijten@xxxxxxxxxxxxxx Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/msm/dsi/dsi_host.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index de00925c94e8..c229cf6eeb9c 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -1761,6 +1761,11 @@ static int dsi_populate_dsc_params(struct msm_dsi_host *msm_host, struct drm_dsc return -EINVAL; } + if (dsc->bits_per_component != 8) { + DRM_DEV_ERROR(&msm_host->pdev->dev, "DSI does not support bits_per_component != 8 yet\n"); + return -EOPNOTSUPP; + } + dsc->rc_model_size = 8192; dsc->first_line_bpg_offset = 12; dsc->rc_edge_factor = 6; -- 2.35.1
