drm/ingenic: Add ingenic_drm_bridge_atomic_enable and disable

ingenic_drm_bridge_atomic_enable allows the CRTC to be enabled after
panels have slept out, and before their display is turned on, solving
a graphical bug on the newvision nv3502c.

Also add ingenic_drm_bridge_atomic_disable to balance it out.
Signed-off-by: Christophe Branchereau <cbranchereau@gmail.com>
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Acked-by: Artur Rojek <contact@artur-rojek.eu>
Link: https://patchwork.freedesktop.org/patch/msgid/20220321133651.291592-2-cbranchereau@gmail.com

drivers/gpu/drm/ingenic/ingenic-drm-drv.c

@@ -226,6 +226,18 @@ static int ingenic_drm_update_pixclk(struct notifier_block *nb,
 	}
 }
 
+static void ingenic_drm_bridge_atomic_enable(struct drm_bridge *bridge,
+					     struct drm_bridge_state *old_bridge_state)
+{
+	struct ingenic_drm *priv = drm_device_get_priv(bridge->dev);
+
+	regmap_write(priv->map, JZ_REG_LCD_STATE, 0);
+
+	regmap_update_bits(priv->map, JZ_REG_LCD_CTRL,
+			   JZ_LCD_CTRL_ENABLE | JZ_LCD_CTRL_DISABLE,
+			   JZ_LCD_CTRL_ENABLE);
+}
+
 static void ingenic_drm_crtc_atomic_enable(struct drm_crtc *crtc,
 					   struct drm_atomic_state *state)
 {
@@ -237,28 +249,20 @@ static void ingenic_drm_crtc_atomic_enable(struct drm_crtc *crtc,
 	if (WARN_ON(IS_ERR(priv_state)))
 		return;
 
-	regmap_write(priv->map, JZ_REG_LCD_STATE, 0);
-
 	/* Set addresses of our DMA descriptor chains */
 	next_id = priv_state->use_palette ? HWDESC_PALETTE : 0;
 	regmap_write(priv->map, JZ_REG_LCD_DA0, dma_hwdesc_addr(priv, next_id));
 	regmap_write(priv->map, JZ_REG_LCD_DA1, dma_hwdesc_addr(priv, 1));
 
-	regmap_update_bits(priv->map, JZ_REG_LCD_CTRL,
-			   JZ_LCD_CTRL_ENABLE | JZ_LCD_CTRL_DISABLE,
-			   JZ_LCD_CTRL_ENABLE);
-
 	drm_crtc_vblank_on(crtc);
 }
 
-static void ingenic_drm_crtc_atomic_disable(struct drm_crtc *crtc,
-					    struct drm_atomic_state *state)
+static void ingenic_drm_bridge_atomic_disable(struct drm_bridge *bridge,
+					      struct drm_bridge_state *old_bridge_state)
 {
-	struct ingenic_drm *priv = drm_crtc_get_priv(crtc);
+	struct ingenic_drm *priv = drm_device_get_priv(bridge->dev);
 	unsigned int var;
 
-	drm_crtc_vblank_off(crtc);
-
 	regmap_update_bits(priv->map, JZ_REG_LCD_CTRL,
 			   JZ_LCD_CTRL_DISABLE, JZ_LCD_CTRL_DISABLE);
 
@@ -267,6 +271,12 @@ static void ingenic_drm_crtc_atomic_disable(struct drm_crtc *crtc,
 				 1000, 0);
 }
 
+static void ingenic_drm_crtc_atomic_disable(struct drm_crtc *crtc,
+					    struct drm_atomic_state *state)
+{
+	drm_crtc_vblank_off(crtc);
+}
+
 static void ingenic_drm_crtc_update_timings(struct ingenic_drm *priv,
 					    struct drm_display_mode *mode)
 {
@@ -968,6 +978,8 @@ static const struct drm_encoder_helper_funcs ingenic_drm_encoder_helper_funcs =
 
 static const struct drm_bridge_funcs ingenic_drm_bridge_funcs = {
 	.attach			= ingenic_drm_bridge_attach,
+	.atomic_enable		= ingenic_drm_bridge_atomic_enable,
+	.atomic_disable		= ingenic_drm_bridge_atomic_disable,
 	.atomic_check		= ingenic_drm_bridge_atomic_check,
 	.atomic_reset		= drm_atomic_helper_bridge_reset,
 	.atomic_duplicate_state	= drm_atomic_helper_bridge_duplicate_state,