Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
drm/msm/dpu: simplify bg_alpha selection
In order to be more obvious in fg_alpha / bg_alpha handling during the
blending programming drop the default setting for background alpha value
and set it explicitly in all cases.
Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@oss.qualcomm.com>
Patchwork: https://patchwork.freedesktop.org/patch/697896/
Link: https://lore.kernel.org/r/20260112-dpu-rework-alpha-v2-1-d168785911d5@oss.qualcomm.com
+3
-1
+3
-1
drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+3
-1
drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
···
335
335
max_alpha = 0x3ff;
336
336
fg_alpha = pstate->base.alpha >> 6;
337
337
}
338
-
bg_alpha = max_alpha - fg_alpha;
339
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340
339
/* default to opaque blending */
341
340
if (pstate->base.pixel_blend_mode == DRM_MODE_BLEND_PIXEL_NONE ||
342
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!format->alpha_enable) {
343
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blend_op = DPU_BLEND_FG_ALPHA_FG_CONST |
344
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DPU_BLEND_BG_ALPHA_BG_CONST;
344
+
bg_alpha = max_alpha - fg_alpha;
345
345
} else if (pstate->base.pixel_blend_mode == DRM_MODE_BLEND_PREMULTI) {
346
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blend_op = DPU_BLEND_FG_ALPHA_FG_CONST |
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DPU_BLEND_BG_ALPHA_FG_PIXEL;
···
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350
blend_op |= DPU_BLEND_BG_MOD_ALPHA |
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DPU_BLEND_BG_INV_MOD_ALPHA;
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} else {
353
+
bg_alpha = 0;
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blend_op |= DPU_BLEND_BG_INV_ALPHA;
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}
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} else {
···
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363
DPU_BLEND_BG_MOD_ALPHA |
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364
DPU_BLEND_BG_INV_MOD_ALPHA;
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365
} else {
366
+
bg_alpha = 0;
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blend_op |= DPU_BLEND_BG_INV_ALPHA;
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}
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369
}