drm/vc4: add extcon hdmi connection uevent

Add extcon hdmi connection and disconnection uevent when extcon
module is enabled.

The vc4_hdmi detection is done by polling way, so extcon uevent
for connection is a bit slow after changing real hdmi cable state.

Signed-off-by: Seung-Woo Kim <sw0312.kim@samsung.com>
Signed-off-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>

[mszyprow: this is a squashed set of the following patches
 from platform/kernel/linux-rpi 'tizen' (c4f85fdcd893) branch:
 drm/vc4: add extcon hdmi connection uevent
 drm/vc4: hdmi: Fix hotplug extcon uevent to works
 ported and adapted to Linux v6.6 kernel base]

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Change-Id: I2a825241cd72befd1f75bd094405f719d4b20638

2 files changed, 44 insertions, 0 deletions

diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.c b/drivers/gpu/drm/vc4/vc4_hdmi.c
index e1f2ce494241..75ceb459783e 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.c
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.c
@@ -40,6 +40,7 @@
 #include <linux/clk.h>
 #include <linux/component.h>
 #include <linux/gpio/consumer.h>
+#include <linux/extcon-provider.h>
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
@@ -516,6 +517,15 @@ static int vc4_hdmi_connector_detect_ctx(struct drm_connector *connector,
 	vc4_hdmi_handle_hotplug(vc4_hdmi, ctx, status);
 	pm_runtime_put(&vc4_hdmi->pdev->dev);
 
+#ifdef CONFIG_EXTCON
+	if (status != vc4_hdmi->status) {
+		extcon_set_state_sync(vc4_hdmi->edev, EXTCON_DISP_HDMI,
+				      (status == connector_status_connected ?
+				      true : false));
+		vc4_hdmi->status = status;
+	}
+#endif
+
 	return status;
 }
 
@@ -3798,6 +3808,13 @@ static void vc4_hdmi_put_ddc_device(void *ptr)
 	put_device(&vc4_hdmi->ddc->dev);
 }
 
+#ifdef CONFIG_EXTCON
+static const unsigned int vc4_hdmi_extcon_cable[] = {
+	EXTCON_DISP_HDMI,
+	EXTCON_NONE,
+};
+#endif
+
 static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
 {
 	const struct vc4_hdmi_variant *variant = of_device_get_match_data(dev);
@@ -3862,6 +3879,23 @@ static int vc4_hdmi_bind(struct device *dev, struct device *master, void *data)
 	if (ret)
 		return ret;
 
+#ifdef CONFIG_EXTCON
+	vc4_hdmi->status = connector_status_disconnected;
+
+	/* Initialize extcon device */
+	vc4_hdmi->edev = devm_extcon_dev_allocate(dev, vc4_hdmi_extcon_cable);
+	if (IS_ERR(vc4_hdmi->edev)) {
+		dev_err(dev, "failed to allocate memory for extcon\n");
+		return PTR_ERR(vc4_hdmi->edev);
+	}
+
+	ret = devm_extcon_dev_register(dev, vc4_hdmi->edev);
+	if (ret) {
+		dev_err(dev, "failed to register extcon device\n");
+		return ret;
+	}
+#endif
+
 	/* Only use the GPIO HPD pin if present in the DT, otherwise
 	 * we'll use the HDMI core's register.
 	 */
diff --git a/drivers/gpu/drm/vc4/vc4_hdmi.h b/drivers/gpu/drm/vc4/vc4_hdmi.h
index 681827a59e84..8edd246be166 100644
--- a/drivers/gpu/drm/vc4/vc4_hdmi.h
+++ b/drivers/gpu/drm/vc4/vc4_hdmi.h
@@ -14,6 +14,10 @@ struct vc4_hdmi;
 struct vc4_hdmi_register;
 struct vc4_hdmi_connector_state;
 
+#ifdef CONFIG_EXTCON
+struct extcon_dev;
+#endif
+
 enum vc4_hdmi_phy_channel {
 	PHY_LANE_0 = 0,
 	PHY_LANE_1,
@@ -236,6 +240,7 @@ struct vc4_hdmi {
 	 * for use outside of KMS hooks. Protected by @mutex.
 	 */
 	enum vc4_hdmi_output_format output_format;
+
 	/**
 	 * @requested_output_format: Copy of @vc4_connector_state.requested_output_format
 	 * for use outside of KMS hooks. Protected by @mutex.
@@ -266,6 +271,11 @@ struct vc4_hdmi {
 	 * ALSA jack detection.
 	 */
 	struct snd_soc_jack hdmi_jack;
+
+#ifdef CONFIG_EXTCON
+	enum drm_connector_status status;
+	struct extcon_dev *edev;
+#endif
 };
 
 #define connector_to_vc4_hdmi(_connector)				\