[PATCH 10/30] drm/sun4i: mixer: Remove setting layer enable bit

Jernej Skrabec jernej.skrabec at gmail.com
Sun Oct 12 12:23:10 PDT 2025


This task is now done by plane atomic update callback. There is no fear
that bit would be set incorrectly, as all register reads are eliminated.

Signed-off-by: Jernej Skrabec <jernej.skrabec at gmail.com>
---
 drivers/gpu/drm/sun4i/sun8i_mixer.c    | 24 ------------------------
 drivers/gpu/drm/sun4i/sun8i_ui_layer.c | 13 ++++++++++++-
 drivers/gpu/drm/sun4i/sun8i_vi_layer.c | 13 ++++++++++++-
 3 files changed, 24 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun8i_mixer.c b/drivers/gpu/drm/sun4i/sun8i_mixer.c
index a3194b71dc6d..1fca05a760b8 100644
--- a/drivers/gpu/drm/sun4i/sun8i_mixer.c
+++ b/drivers/gpu/drm/sun4i/sun8i_mixer.c
@@ -250,24 +250,6 @@ int sun8i_mixer_drm_format_to_hw(u32 format, u32 *hw_format)
 	return -EINVAL;
 }
 
-static void sun8i_layer_enable(struct sun8i_layer *layer, bool enable)
-{
-	u32 ch_base = sun8i_channel_base(layer->mixer, layer->channel);
-	u32 val, reg, mask;
-
-	if (layer->type == SUN8I_LAYER_TYPE_UI) {
-		val = enable ? SUN8I_MIXER_CHAN_UI_LAYER_ATTR_EN : 0;
-		mask = SUN8I_MIXER_CHAN_UI_LAYER_ATTR_EN;
-		reg = SUN8I_MIXER_CHAN_UI_LAYER_ATTR(ch_base, layer->overlay);
-	} else {
-		val = enable ? SUN8I_MIXER_CHAN_VI_LAYER_ATTR_EN : 0;
-		mask = SUN8I_MIXER_CHAN_VI_LAYER_ATTR_EN;
-		reg = SUN8I_MIXER_CHAN_VI_LAYER_ATTR(ch_base, layer->overlay);
-	}
-
-	regmap_update_bits(layer->mixer->engine.regs, reg, mask, val);
-}
-
 static void sun8i_mixer_commit(struct sunxi_engine *engine,
 			       struct drm_crtc *crtc,
 			       struct drm_atomic_state *state)
@@ -304,12 +286,6 @@ static void sun8i_mixer_commit(struct sunxi_engine *engine,
 				 plane->base.id, layer->channel, layer->overlay,
 				 enable, zpos, x, y, w, h);
 
-		/*
-		 * We always update the layer enable bit, because it can clear
-		 * spontaneously for unknown reasons.
-		 */
-		sun8i_layer_enable(layer, enable);
-
 		if (!enable)
 			continue;
 
diff --git a/drivers/gpu/drm/sun4i/sun8i_ui_layer.c b/drivers/gpu/drm/sun4i/sun8i_ui_layer.c
index 8634d2ee613a..9d5d5e0b7e63 100644
--- a/drivers/gpu/drm/sun4i/sun8i_ui_layer.c
+++ b/drivers/gpu/drm/sun4i/sun8i_ui_layer.c
@@ -25,6 +25,15 @@
 #include "sun8i_ui_scaler.h"
 #include "sun8i_vi_scaler.h"
 
+static void sun8i_ui_layer_disable(struct sun8i_mixer *mixer,
+				   int channel, int overlay)
+{
+	u32 ch_base = sun8i_channel_base(mixer, channel);
+
+	regmap_write(mixer->engine.regs,
+		     SUN8I_MIXER_CHAN_UI_LAYER_ATTR(ch_base, overlay), 0);
+}
+
 static void sun8i_ui_layer_update_attributes(struct sun8i_mixer *mixer,
 					     int channel, int overlay,
 					     struct drm_plane *plane)
@@ -201,8 +210,10 @@ static void sun8i_ui_layer_atomic_update(struct drm_plane *plane,
 	struct sun8i_layer *layer = plane_to_sun8i_layer(plane);
 	struct sun8i_mixer *mixer = layer->mixer;
 
-	if (!new_state->crtc || !new_state->visible)
+	if (!new_state->crtc || !new_state->visible) {
+		sun8i_ui_layer_disable(mixer, layer->channel, layer->overlay);
 		return;
+	}
 
 	sun8i_ui_layer_update_attributes(mixer, layer->channel,
 					 layer->overlay, plane);
diff --git a/drivers/gpu/drm/sun4i/sun8i_vi_layer.c b/drivers/gpu/drm/sun4i/sun8i_vi_layer.c
index dcc4429368d6..727117658c6c 100644
--- a/drivers/gpu/drm/sun4i/sun8i_vi_layer.c
+++ b/drivers/gpu/drm/sun4i/sun8i_vi_layer.c
@@ -18,6 +18,15 @@
 #include "sun8i_vi_layer.h"
 #include "sun8i_vi_scaler.h"
 
+static void sun8i_vi_layer_disable(struct sun8i_mixer *mixer,
+				   int channel, int overlay)
+{
+	u32 ch_base = sun8i_channel_base(mixer, channel);
+
+	regmap_write(mixer->engine.regs,
+		     SUN8I_MIXER_CHAN_VI_LAYER_ATTR(ch_base, overlay), 0);
+}
+
 static void sun8i_vi_layer_update_attributes(struct sun8i_mixer *mixer,
 					     int channel, int overlay,
 					     struct drm_plane *plane)
@@ -320,8 +329,10 @@ static void sun8i_vi_layer_atomic_update(struct drm_plane *plane,
 	struct sun8i_layer *layer = plane_to_sun8i_layer(plane);
 	struct sun8i_mixer *mixer = layer->mixer;
 
-	if (!new_state->crtc || !new_state->visible)
+	if (!new_state->crtc || !new_state->visible) {
+		sun8i_vi_layer_disable(mixer, layer->channel, layer->overlay);
 		return;
+	}
 
 	sun8i_vi_layer_update_attributes(mixer, layer->channel,
 					 layer->overlay, plane);
-- 
2.51.0




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