From 5e0656b125346d9a1ef65e72c6d3196b8ea6b1e1 Mon Sep 17 00:00:00 2001 From: Vladimir Lypak Date: Fri, 17 Oct 2025 19:58:39 +0000 Subject: [PATCH] drm/msm/dpu: Require linear modifier for writeback framebuffers UBWC-related register configuration for writeback is not implemented in the driver yet but there aren't any checks for non-linear modifiers in atomic_check. Thus when compressed framebuffer is attached to writeback connector it will be filled with linear image data. This patch forbids non-linear modifiers for writeback framebuffers until UBWC support for writeback is properly implemented. Fixes: 71174f362d67 ("drm/msm/dpu: move writeback's atomic_check to dpu_writeback.c") Signed-off-by: Vladimir Lypak Reviewed-by: Dmitry Baryshkov Patchwork: https://patchwork.freedesktop.org/patch/681922/ Link: https://lore.kernel.org/r/20251017-b4-dpu-fixes-v1-5-40ce5993eeb6@gmail.com Signed-off-by: Dmitry Baryshkov --- drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c index cd73468e369a9..7545c0293efbd 100644 --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_writeback.c @@ -72,6 +72,9 @@ static int dpu_wb_conn_atomic_check(struct drm_connector *connector, DPU_ERROR("invalid fb w=%d, maxlinewidth=%u\n", fb->width, dpu_wb_conn->maxlinewidth); return -EINVAL; + } else if (fb->modifier != DRM_FORMAT_MOD_LINEAR) { + DPU_ERROR("unsupported fb modifier:%#llx\n", fb->modifier); + return -EINVAL; } return drm_atomic_helper_check_wb_connector_state(conn_state->connector, conn_state->state); -- 2.47.3