drm/msm/dp: Add Display Port HPD feature

Configure HPD registers in DP controller and
enable HPD interrupt.

Add interrupt to handle HPD connect and disconnect events.

Changes in v8: None

Signed-off-by: Tanmay Shah <tanmay@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

1 files changed, 101 insertions, 7 deletions

diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index c8851f4bbf72..925c89720a16 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -17,6 +17,7 @@
 #include "dp_power.h"
 #include "dp_catalog.h"
 #include "dp_aux.h"
+#include "dp_reg.h"
 #include "dp_link.h"
 #include "dp_panel.h"
 #include "dp_ctrl.h"
@@ -36,6 +37,7 @@ struct dp_display_private {
 	bool power_on;
 	bool hpd_irq_on;
 	bool audio_supported;
+	atomic_t hpd_isr_status;
 
 	struct platform_device *pdev;
 	struct dentry *root;
@@ -54,6 +56,8 @@ struct dp_display_private {
 	struct dp_usbpd_cb usbpd_cb;
 	struct dp_display_mode dp_mode;
 	struct msm_dp dp_display;
+
+	struct delayed_work config_hpd_work;
 };
 
 static const struct of_device_id dp_dt_match[] = {
@@ -64,6 +68,20 @@ static const struct of_device_id dp_dt_match[] = {
 static irqreturn_t dp_display_irq(int irq, void *dev_id)
 {
 	struct dp_display_private *dp = dev_id;
+	irqreturn_t ret = IRQ_HANDLED;
+	u32 hpd_isr_status;
+
+	if (!dp) {
+		DRM_ERROR("invalid data\n");
+		return IRQ_NONE;
+	}
+
+	hpd_isr_status = dp_catalog_hpd_get_intr_status(dp->catalog);
+
+	if (hpd_isr_status & DP_DP_HPD_INT_MASK) {
+		atomic_set(&dp->hpd_isr_status, hpd_isr_status);
+		ret = IRQ_WAKE_THREAD;
+	}
 
 	/* DP controller isr */
 	dp_ctrl_isr(dp->ctrl);
@@ -71,6 +89,54 @@ static irqreturn_t dp_display_irq(int irq, void *dev_id)
 	/* DP aux isr */
 	dp_aux_isr(dp->aux);
 
+	return ret;
+}
+
+static irqreturn_t dp_display_hpd_isr_work(int irq, void *data)
+{
+	struct dp_display_private *dp;
+	struct dp_usbpd *hpd;
+	u32 isr = 0;
+
+	dp = (struct dp_display_private *)data;
+	if (!dp)
+		return IRQ_NONE;
+
+	isr = atomic_read(&dp->hpd_isr_status);
+
+	/* reset to default */
+	atomic_set(&dp->hpd_isr_status, 0);
+
+	hpd = dp->usbpd;
+	if (!hpd)
+		return IRQ_NONE;
+
+	if (isr & DP_DP_HPD_PLUG_INT_MASK &&
+		isr & DP_DP_HPD_STATE_STATUS_CONNECTED) {
+		hpd->hpd_high = 1;
+		dp->usbpd_cb.configure(&dp->pdev->dev);
+	} else if (isr & DP_DP_HPD_UNPLUG_INT_MASK &&
+		(isr & DP_DP_HPD_STATE_STATUS_MASK) ==
+			 DP_DP_HPD_STATE_STATUS_DISCONNECTED) {
+
+		/* disable HPD plug interrupt until disconnect is done
+		 */
+		dp_catalog_hpd_config_intr(dp->catalog,
+			DP_DP_HPD_PLUG_INT_MASK | DP_DP_IRQ_HPD_INT_MASK,
+			false);
+
+		hpd->hpd_high = 0;
+
+		/* We don't need separate work for disconnect as
+		 * connect/attention interrupts are disabled
+		 */
+		dp->usbpd_cb.disconnect(&dp->pdev->dev);
+
+		dp_catalog_hpd_config_intr(dp->catalog,
+			DP_DP_HPD_PLUG_INT_MASK | DP_DP_IRQ_HPD_INT_MASK,
+			true);
+	}
+
 	return IRQ_HANDLED;
 }
 
@@ -212,8 +278,6 @@ static int dp_display_process_hpd_high(struct dp_display_private *dp)
 	int rc = 0;
 	struct edid *edid;
 
-	dp_aux_init(dp->aux);
-
 	if (dp->link->psm_enabled)
 		goto notify;
 
@@ -270,10 +334,6 @@ static void dp_display_host_deinit(struct dp_display_private *dp)
 		return;
 	}
 
-	dp_ctrl_host_deinit(dp->ctrl);
-	dp_aux_deinit(dp->aux);
-	dp_power_deinit(dp->power);
-	disable_irq(dp->irq);
 	dp->core_initialized = false;
 }
 
@@ -630,7 +690,8 @@ int dp_display_request_irq(struct msm_dp *dp_display)
 		return rc;
 	}
 
-	rc = devm_request_irq(&dp->pdev->dev, dp->irq, dp_display_irq,
+	rc = devm_request_threaded_irq(&dp->pdev->dev, dp->irq,
+		dp_display_irq, dp_display_hpd_isr_work,
 		IRQF_TRIGGER_HIGH, "dp_display_isr", dp);
 	if (rc < 0) {
 		DRM_ERROR("failed to request IRQ%u: %d\n",
@@ -829,6 +890,39 @@ void __exit msm_dp_unregister(void)
 	platform_driver_unregister(&dp_display_driver);
 }
 
+static void dp_display_config_hpd_work(struct work_struct *work)
+{
+	struct dp_display_private *dp;
+	struct delayed_work *dw = to_delayed_work(work);
+
+	dp = container_of(dw, struct dp_display_private, config_hpd_work);
+
+	dp_display_host_init(dp);
+	dp_catalog_ctrl_hpd_config(dp->catalog);
+
+	/* set default to 0 */
+	atomic_set(&dp->hpd_isr_status, 0);
+
+	/* Enable interrupt first time
+	 * we are leaving dp clocks on during disconnect
+	 * and never disable interrupt
+	 */
+	enable_irq(dp->irq);
+}
+
+void msm_dp_irq_postinstall(struct msm_dp *dp_display)
+{
+	struct dp_display_private *dp;
+
+	if (!dp_display)
+		return;
+
+	dp = container_of(dp_display, struct dp_display_private, dp_display);
+
+	INIT_DELAYED_WORK(&dp->config_hpd_work, dp_display_config_hpd_work);
+	queue_delayed_work(system_wq, &dp->config_hpd_work, HZ * 10);
+}
+
 int msm_dp_modeset_init(struct msm_dp *dp_display, struct drm_device *dev,
 			struct drm_encoder *encoder)
 {