[PATCH v2 3/4] drm/msm/dp: add hook_plugged_cb hdmi-codec op for MSM DP driver

[Abhinav Kumar]

Add the hook_plugged_cb op for the MSM DP driver to signal connect
and disconnect events to the hdmi-codec driver which in-turn shall
notify the audio subsystem to start a new or teardown an existing
session.

Changes in v2: none

Signed-off-by: Abhinav Kumar <abhinavk at codeaurora.org>
---
 drivers/gpu/drm/msm/dp/dp_audio.c   | 25 ++++++++++++++++++++++++-
 drivers/gpu/drm/msm/dp/dp_display.c | 25 +++++++++++++++++++++++++
 drivers/gpu/drm/msm/dp/dp_display.h |  7 +++++++
 3 files changed, 56 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/dp/dp_audio.c b/drivers/gpu/drm/msm/dp/dp_audio.c
index 75556eea1059..11fa5ad7a801 100644
--- a/drivers/gpu/drm/msm/dp/dp_audio.c
+++ b/drivers/gpu/drm/msm/dp/dp_audio.c
@@ -10,7 +10,6 @@
 
 #include <drm/drm_dp_helper.h>
 #include <drm/drm_edid.h>
-#include <sound/hdmi-codec.h>
 
 #include "dp_catalog.h"
 #include "dp_audio.h"
@@ -442,6 +441,29 @@ static struct dp_audio_private *dp_audio_get_data(struct platform_device *pdev)
 	return container_of(dp_audio, struct dp_audio_private, dp_audio);
 }
 
+static int dp_audio_hook_plugged_cb(struct device *dev, void *data,
+		hdmi_codec_plugged_cb fn,
+		struct device *codec_dev)
+{
+
+	struct platform_device *pdev;
+	struct msm_dp *dp_display;
+
+	pdev = to_platform_device(dev);
+	if (!pdev) {
+		pr_err("invalid input\n");
+		return -ENODEV;
+	}
+
+	dp_display = platform_get_drvdata(pdev);
+	if (!dp_display) {
+		pr_err("invalid input\n");
+		return -ENODEV;
+	}
+
+	return dp_display_set_plugged_cb(dp_display, fn, codec_dev);
+}
+
 static int dp_audio_get_eld(struct device *dev,
 	void *data, uint8_t *buf, size_t len)
 {
@@ -513,6 +535,7 @@ static const struct hdmi_codec_ops dp_audio_codec_ops = {
 	.hw_params = dp_audio_hw_params,
 	.audio_shutdown = dp_audio_shutdown,
 	.get_eld = dp_audio_get_eld,
+	.hook_plugged_cb = dp_audio_hook_plugged_cb,
 };
 
 static struct hdmi_codec_pdata codec_data = {
diff --git a/drivers/gpu/drm/msm/dp/dp_display.c b/drivers/gpu/drm/msm/dp/dp_display.c
index 3120e172adc2..5b4dcd5621d8 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.c
+++ b/drivers/gpu/drm/msm/dp/dp_display.c
@@ -709,6 +709,13 @@ static int dp_display_prepare(struct msm_dp *dp)
 	return 0;
 }
 
+static void dp_display_handle_plugged_change(struct msm_dp *dp_display,
+		bool plugged)
+{
+	if (dp_display->plugged_cb && dp_display->codec_dev)
+		dp_display->plugged_cb(dp_display->codec_dev, plugged);
+}
+
 static int dp_display_enable(struct dp_display_private *dp, u32 data)
 {
 	int rc = 0;
@@ -739,6 +746,8 @@ static int dp_display_post_enable(struct msm_dp *dp_display)
 		dp->audio->lane_count = dp->link->link_params.num_lanes;
 	}
 
+	/* signal the connect event late to synchronize video and display */
+	dp_display_handle_plugged_change(dp_display, true);
 	return 0;
 }
 
@@ -748,6 +757,9 @@ static int dp_display_pre_disable(struct msm_dp *dp_display)
 
 	dp = container_of(dp_display, struct dp_display_private, dp_display);
 
+	/* signal the disconnect event early to ensure proper teardown */
+	dp_display_handle_plugged_change(dp_display, false);
+
 	return 0;
 }
 
@@ -770,6 +782,19 @@ static int dp_display_unprepare(struct msm_dp *dp)
 	return 0;
 }
 
+int dp_display_set_plugged_cb(struct msm_dp *dp_display,
+		hdmi_codec_plugged_cb fn, struct device *codec_dev)
+{
+	bool plugged;
+
+	dp_display->plugged_cb = fn;
+	dp_display->codec_dev = codec_dev;
+	plugged = dp_display->is_connected;
+	dp_display_handle_plugged_change(dp_display, plugged);
+
+	return 0;
+}
+
 int dp_display_validate_mode(struct msm_dp *dp, u32 mode_pclk_khz)
 {
 	const u32 num_components = 3, default_bpp = 24;
diff --git a/drivers/gpu/drm/msm/dp/dp_display.h b/drivers/gpu/drm/msm/dp/dp_display.h
index 1e0d2b9d9a2a..5020faf360db 100644
--- a/drivers/gpu/drm/msm/dp/dp_display.h
+++ b/drivers/gpu/drm/msm/dp/dp_display.h
@@ -7,18 +7,25 @@
 #define _DP_DISPLAY_H_
 
 #include "dp_panel.h"
+#include <sound/hdmi-codec.h>
 
 struct msm_dp {
 	struct drm_device *drm_dev;
+	struct device *codec_dev;
 	struct drm_connector *connector;
 	struct drm_encoder *encoder;
 	bool is_connected;
+
+	hdmi_codec_plugged_cb plugged_cb;
+
 	u32 max_pclk_khz;
 
 	u32 max_dp_lanes;
 	struct dp_audio *dp_audio;
 };
 
+int dp_display_set_plugged_cb(struct msm_dp *dp_display,
+		hdmi_codec_plugged_cb fn, struct device *codec_dev);
 int dp_display_validate_mode(struct msm_dp *dp_display, u32 mode_pclk_khz);
 int dp_display_get_modes(struct msm_dp *dp_display,
 		struct dp_display_mode *dp_mode);
-- 
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