From 51e085ee4fdc61d88621e75a1c6f5c4fafb3fe35 Mon Sep 17 00:00:00 2001 From: Jun Nie Date: Tue, 19 Aug 2025 09:30:57 +0800 Subject: [PATCH] drm/msm/dpu: decide right side per last bit Currently, only one pair of mixers is supported, so a non-zero counter value is sufficient to identify the correct mixer within that pair. However, future implementations may involve multiple mixer pairs. With the current implementation, all mixers within the second pair would be incorrectly selected as right mixer. To correctly select the mixer within a pair, test the least significant bit of the counter. If the least significant bit is not set, select the mixer as left one; otherwise, select the mixer as right one for all pairs. Signed-off-by: Jun Nie Reviewed-by: Dmitry Baryshkov Reviewed-by: Jessica Zhang Patchwork: https://patchwork.freedesktop.org/patch/669226/ Link: https://lore.kernel.org/r/20250819-v6-16-rc2-quad-pipe-upstream-v15-3-2c7a85089db8@linaro.org Signed-off-by: Dmitry Baryshkov --- drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c index d59512e45af05..4b970a59deafd 100644 --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c @@ -377,11 +377,10 @@ static void _dpu_crtc_setup_blend_cfg(struct dpu_crtc_mixer *mixer, static void _dpu_crtc_program_lm_output_roi(struct drm_crtc *crtc) { struct dpu_crtc_state *crtc_state; - int lm_idx, lm_horiz_position; + int lm_idx; crtc_state = to_dpu_crtc_state(crtc->state); - lm_horiz_position = 0; for (lm_idx = 0; lm_idx < crtc_state->num_mixers; lm_idx++) { const struct drm_rect *lm_roi = &crtc_state->lm_bounds[lm_idx]; struct dpu_hw_mixer *hw_lm = crtc_state->mixers[lm_idx].hw_lm; @@ -392,7 +391,7 @@ static void _dpu_crtc_program_lm_output_roi(struct drm_crtc *crtc) cfg.out_width = drm_rect_width(lm_roi); cfg.out_height = drm_rect_height(lm_roi); - cfg.right_mixer = lm_horiz_position++; + cfg.right_mixer = lm_idx & 0x1; cfg.flags = 0; hw_lm->ops.setup_mixer_out(hw_lm, &cfg); } -- 2.47.3