This is a note to let you know that I've just added the patch titled drm/i915: Handle max_bpc==16 to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-i915-handle-max_bpc-16.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From d2e3fce9ddafe689c6f7cb355f23560637e30b9d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@xxxxxxxxxxxxxxx> Date: Tue, 10 Nov 2020 23:04:47 +0200 Subject: drm/i915: Handle max_bpc==16 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> commit d2e3fce9ddafe689c6f7cb355f23560637e30b9d upstream. EDID can declare the maximum supported bpc up to 16, and apparently there are displays that do so. Currently we assume 12 bpc is tha max. Fix the assumption and toss in a MISSING_CASE() for any other value we don't expect to see. This fixes modesets with a display with EDID max bpc > 12. Previously any modeset would just silently fail on platforms that didn't otherwise limit this via the max_bpc property. In particular we don't add the max_bpc property to HDMI ports on gmch platforms, and thus we would see the raw max_bpc coming from the EDID. I suppose we could already adjust this to also allow 16bpc, but seeing as no current platform supports that there is little point. Cc: stable@xxxxxxxxxxxxxxx Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/2632 Signed-off-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> Link: https://patchwork.freedesktop.org/patch/msgid/20201110210447.27454-1-ville.syrjala@xxxxxxxxxxxxxxx Reviewed-by: José Roberto de Souza <jose.souza@xxxxxxxxx> (cherry picked from commit 2ca5a7b85b0c2b97ef08afbd7799b022e29f192e) Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/gpu/drm/i915/display/intel_display.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/gpu/drm/i915/display/intel_display.c +++ b/drivers/gpu/drm/i915/display/intel_display.c @@ -11893,10 +11893,11 @@ compute_sink_pipe_bpp(const struct drm_c case 10 ... 11: bpp = 10 * 3; break; - case 12: + case 12 ... 16: bpp = 12 * 3; break; default: + MISSING_CASE(conn_state->max_bpc); return -EINVAL; } Patches currently in stable-queue which might be from ville.syrjala@xxxxxxxxxxxxxxx are queue-5.4/drm-i915-handle-max_bpc-16.patch