From 3187deef82d1f7c9eeeb3f46c5a1879cd3e61be1 Mon Sep 17 00:00:00 2001
From: Algea Cao <algea.cao@rock-chips.com>
Date: Wed, 6 Nov 2019 11:06:59 +0800
Subject: [PATCH] drm: bridge: dw-hdmi: using extcon instead of switch

Switch is no longer available in kernel 4.19, so
we use extcon instead.

the hdmi connect status node:

/sys/class/extcon/extconX/state

HDMI=0:
	hdmi is disconnected
HDMI=1:
	hdmi is connected

Change-Id: I806d8fd5b9b4b36f15aa6aec275fad2ecf122e91
Signed-off-by: Algea Cao <algea.cao@rock-chips.com>
---
 drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 46 +++++++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
index 1a53af4564d0..99216b84c45c 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
@@ -9,6 +9,8 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/err.h>
+#include <linux/extcon.h>
+#include <linux/extcon-provider.h>
 #include <linux/hdmi.h>
 #include <linux/irq.h>
 #include <linux/module.h>
@@ -49,6 +51,11 @@
 
 #define HDMI14_MAX_TMDSCLK	340000000
 
+static const unsigned int dw_hdmi_cable[] = {
+	EXTCON_DISP_HDMI,
+	EXTCON_NONE,
+};
+
 enum hdmi_datamap {
 	RGB444_8B = 0x01,
 	RGB444_10B = 0x03,
@@ -256,6 +263,8 @@ struct dw_hdmi {
 	unsigned int audio_n;
 	bool audio_enable;
 
+	struct extcon_dev *extcon;
+
 	unsigned int reg_shift;
 	struct regmap *regm;
 	void (*enable_audio)(struct dw_hdmi *hdmi);
@@ -334,6 +343,8 @@ static void repo_hpd_event(struct work_struct *p_work)
 		drm_helper_hpd_irq_event(hdmi->bridge.dev);
 		drm_bridge_hpd_notify(&hdmi->bridge, status);
 	}
+
+	extcon_set_state_sync(hdmi->extcon, EXTCON_DISP_HDMI, hdmi->hpd_state);
 }
 
 static bool check_hdmi_irq(struct dw_hdmi *hdmi, int intr_stat,
@@ -2715,6 +2726,16 @@ static void dw_hdmi_connector_force(struct drm_connector *connector)
 					     connector);
 
 	mutex_lock(&hdmi->mutex);
+
+	if (!hdmi->disabled && hdmi->force != connector->force) {
+		if (connector->force == DRM_FORCE_OFF)
+			extcon_set_state_sync(hdmi->extcon, EXTCON_DISP_HDMI,
+					      false);
+		else if (connector->force == DRM_FORCE_ON)
+			extcon_set_state_sync(hdmi->extcon, EXTCON_DISP_HDMI,
+					      true);
+	}
+
 	hdmi->force = connector->force;
 	dw_hdmi_update_power(hdmi);
 	dw_hdmi_update_phy_mask(hdmi);
@@ -3650,6 +3671,8 @@ struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
 	mutex_init(&hdmi->cec_notifier_mutex);
 	spin_lock_init(&hdmi->audio_lock);
 
+	dev_set_name(dev, "hdmi");
+
 	ddc_node = of_parse_phandle(np, "ddc-i2c-bus", 0);
 	if (ddc_node) {
 		hdmi->ddc = of_get_i2c_adapter_by_node(ddc_node);
@@ -3874,6 +3897,29 @@ struct dw_hdmi *dw_hdmi_probe(struct platform_device *pdev,
 		hdmi->cec = platform_device_register_full(&pdevinfo);
 	}
 
+	hdmi->extcon = devm_extcon_dev_allocate(hdmi->dev, dw_hdmi_cable);
+	if (IS_ERR(hdmi->extcon)) {
+		ret = PTR_ERR(hdmi->extcon);
+		dev_err(hdmi->dev, "allocate extcon failed: %d\n", ret);
+		goto err_iahb;
+	}
+
+	ret = devm_extcon_dev_register(hdmi->dev, hdmi->extcon);
+	if (ret) {
+		dev_err(hdmi->dev, "failed to register extcon: %d\n",
+			ret);
+		goto err_iahb;
+	}
+
+	ret = extcon_set_property_capability(hdmi->extcon, EXTCON_DISP_HDMI,
+					     EXTCON_PROP_DISP_HPD);
+	if (ret) {
+		dev_err(hdmi->dev,
+			"failed to set USB property capability: %d\n",
+			ret);
+		goto err_iahb;
+	}
+
 	drm_bridge_add(&hdmi->bridge);
 
 	dw_hdmi_register_debugfs(dev, hdmi);