[PATCH v4 52/78] drm/vc4: hdmi: Add reset callback

Maxime Ripard maxime at cerno.tech
Wed Jul 8 13:42:00 EDT 2020


The BCM2711 and BCM283x HDMI controllers use a slightly different reset
sequence, so let's add a callback to reset the controller.

Signed-off-by: Maxime Ripard <maxime at cerno.tech>
---
 drivers/gpu/drm/vc4/vc4_hdmi.c | 31 ++++++++++++++++++-------------
 drivers/gpu/drm/vc4/vc4_hdmi.h |  3 +++
 2 files changed, 21 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index a4fed1439bf3..80bc3dd9d4a8 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -69,6 +69,21 @@ static int vc4_hdmi_debugfs_regs(struct seq_file *m, void *unused)
 	return 0;
 }
 
+static void vc4_hdmi_reset(struct vc4_hdmi *vc4_hdmi)
+{
+	HDMI_WRITE(HDMI_M_CTL, VC4_HD_M_SW_RST);
+	udelay(1);
+	HDMI_WRITE(HDMI_M_CTL, 0);
+
+	HDMI_WRITE(HDMI_M_CTL, VC4_HD_M_ENABLE);
+
+	HDMI_WRITE(HDMI_SW_RESET_CONTROL,
+		   VC4_HDMI_SW_RESET_HDMI |
+		   VC4_HDMI_SW_RESET_FORMAT_DETECT);
+
+	HDMI_WRITE(HDMI_SW_RESET_CONTROL, 0);
+}
+
 static enum drm_connector_status
 vc4_hdmi_connector_detect(struct drm_connector *connector, bool force)
 {
@@ -363,11 +378,8 @@ static void vc4_hdmi_encoder_enable(struct drm_encoder *encoder)
 		return;
 	}
 
-	HDMI_WRITE(HDMI_SW_RESET_CONTROL,
-		   VC4_HDMI_SW_RESET_HDMI |
-		   VC4_HDMI_SW_RESET_FORMAT_DETECT);
-
-	HDMI_WRITE(HDMI_SW_RESET_CONTROL, 0);
+	if (vc4_hdmi->variant->reset)
+		vc4_hdmi->variant->reset(vc4_hdmi);
 
 	/* PHY should be in reset, like
 	 * vc4_hdmi_encoder_disable() does.
@@ -1292,14 +1304,6 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
 		vc4_hdmi->hpd_active_low = hpd_gpio_flags & OF_GPIO_ACTIVE_LOW;
 	}
 
-	/* HDMI core must be enabled. */
-	if (!(HDMI_READ(HDMI_M_CTL) & VC4_HD_M_ENABLE)) {
-		HDMI_WRITE(HDMI_M_CTL, VC4_HD_M_SW_RST);
-		udelay(1);
-		HDMI_WRITE(HDMI_M_CTL, 0);
-
-		HDMI_WRITE(HDMI_M_CTL, VC4_HD_M_ENABLE);
-	}
 	pm_runtime_enable(dev);
 
 	drm_simple_encoder_init(drm, encoder, DRM_MODE_ENCODER_TMDS);
@@ -1428,6 +1432,7 @@ static const struct vc4_hdmi_variant bcm2835_variant = {
 	.num_registers		= ARRAY_SIZE(vc4_hdmi_fields),
 
 	.init_resources		= vc4_hdmi_init_resources,
+	.reset			= vc4_hdmi_reset,
 };
 
 static const struct of_device_id vc4_hdmi_dt_match[] = {
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index b36e0210671f..17a30589f39c 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -35,6 +35,9 @@ struct vc4_hdmi_variant {
 	 * clocks, etc) for that variant.
 	 */
 	int (*init_resources)(struct vc4_hdmi *vc4_hdmi);
+
+	/* Callback to reset the HDMI block */
+	void (*reset)(struct vc4_hdmi *vc4_hdmi);
 };
 
 /* HDMI audio information */
-- 
git-series 0.9.1



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