diff mbox series

[v10,03/10] drm/connector: implement generic HDMI audio helpers

Message ID 20241224-drm-bridge-hdmi-connector-v10-3-dc89577cd438@linaro.org (mailing list archive)
State New
Headers show
Series drm: add DRM HDMI Codec framework | expand

Commit Message

Dmitry Baryshkov Dec. 24, 2024, 1:47 a.m. UTC
Several DRM drivers implement HDMI codec support (despite its name it
applies to both HDMI and DisplayPort drivers). Implement generic
framework to be used by these drivers. This removes a requirement to
implement get_eld() callback and provides default implementation for
codec's plug handling.

Acked-by: Maxime Ripard <mripard@kernel.org>
Tested-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
---
 drivers/gpu/drm/display/Kconfig                 |   6 +
 drivers/gpu/drm/display/Makefile                |   2 +
 drivers/gpu/drm/display/drm_hdmi_audio_helper.c | 190 ++++++++++++++++++++++++
 drivers/gpu/drm/drm_connector.c                 |   5 +
 include/drm/display/drm_hdmi_audio_helper.h     |  22 +++
 include/drm/drm_connector.h                     | 116 +++++++++++++++
 6 files changed, 341 insertions(+)
diff mbox series

Patch

diff --git a/drivers/gpu/drm/display/Kconfig b/drivers/gpu/drm/display/Kconfig
index 6a4e892afcf8966b45f50ce1f2530707441eda51..80c1953cac14a088d764acd45df03debfcb95e7c 100644
--- a/drivers/gpu/drm/display/Kconfig
+++ b/drivers/gpu/drm/display/Kconfig
@@ -75,6 +75,12 @@  config DRM_DISPLAY_HDCP_HELPER
 	help
 	  DRM display helpers for HDCP.
 
+config DRM_DISPLAY_HDMI_AUDIO_HELPER
+	bool
+	help
+	  DRM display helpers for HDMI Audio functionality (generic HDMI Codec
+	  implementation).
+
 config DRM_DISPLAY_HDMI_HELPER
 	bool
 	help
diff --git a/drivers/gpu/drm/display/Makefile b/drivers/gpu/drm/display/Makefile
index 629c834c3192c61ab8e071223c6a08b98d295b0c..b17879b957d5401721396e247fa346387cf6c48a 100644
--- a/drivers/gpu/drm/display/Makefile
+++ b/drivers/gpu/drm/display/Makefile
@@ -14,6 +14,8 @@  drm_display_helper-$(CONFIG_DRM_DISPLAY_DP_TUNNEL) += \
 drm_display_helper-$(CONFIG_DRM_DISPLAY_DSC_HELPER) += \
 	drm_dsc_helper.o
 drm_display_helper-$(CONFIG_DRM_DISPLAY_HDCP_HELPER) += drm_hdcp_helper.o
+drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_AUDIO_HELPER) += \
+	drm_hdmi_audio_helper.o
 drm_display_helper-$(CONFIG_DRM_DISPLAY_HDMI_HELPER) += \
 	drm_hdmi_helper.o \
 	drm_scdc_helper.o
diff --git a/drivers/gpu/drm/display/drm_hdmi_audio_helper.c b/drivers/gpu/drm/display/drm_hdmi_audio_helper.c
new file mode 100644
index 0000000000000000000000000000000000000000..05afc9f0bdd6b6f00d74223a9d8875e6d16aea5f
--- /dev/null
+++ b/drivers/gpu/drm/display/drm_hdmi_audio_helper.c
@@ -0,0 +1,190 @@ 
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright (c) 2024 Linaro Ltd
+ */
+
+#include <linux/mutex.h>
+#include <linux/of_graph.h>
+#include <linux/platform_device.h>
+
+#include <drm/drm_connector.h>
+#include <drm/drm_device.h>
+#include <drm/display/drm_hdmi_audio_helper.h>
+
+#include <sound/hdmi-codec.h>
+
+static int drm_connector_hdmi_audio_startup(struct device *dev, void *data)
+{
+	struct drm_connector *connector = data;
+	const struct drm_connector_hdmi_audio_funcs *funcs =
+		connector->hdmi_audio.funcs;
+
+	if (funcs->startup)
+		return funcs->startup(connector);
+
+	return 0;
+}
+
+static int drm_connector_hdmi_audio_prepare(struct device *dev, void *data,
+					    struct hdmi_codec_daifmt *fmt,
+					    struct hdmi_codec_params *hparms)
+{
+	struct drm_connector *connector = data;
+	const struct drm_connector_hdmi_audio_funcs *funcs =
+		connector->hdmi_audio.funcs;
+
+	return funcs->prepare(connector, fmt, hparms);
+}
+
+static void drm_connector_hdmi_audio_shutdown(struct device *dev, void *data)
+{
+	struct drm_connector *connector = data;
+	const struct drm_connector_hdmi_audio_funcs *funcs =
+		connector->hdmi_audio.funcs;
+
+	return funcs->shutdown(connector);
+}
+
+static int drm_connector_hdmi_audio_mute_stream(struct device *dev, void *data,
+						bool enable, int direction)
+{
+	struct drm_connector *connector = data;
+	const struct drm_connector_hdmi_audio_funcs *funcs =
+		connector->hdmi_audio.funcs;
+
+	if (funcs->mute_stream)
+		return funcs->mute_stream(connector, enable, direction);
+
+	return -ENOTSUPP;
+}
+
+static int drm_connector_hdmi_audio_get_dai_id(struct snd_soc_component *comment,
+					       struct device_node *endpoint,
+					       void *data)
+{
+	struct drm_connector *connector = data;
+	struct of_endpoint of_ep;
+	int ret;
+
+	if (connector->hdmi_audio.dai_port < 0)
+		return -ENOTSUPP;
+
+	ret = of_graph_parse_endpoint(endpoint, &of_ep);
+	if (ret < 0)
+		return ret;
+
+	if (of_ep.port == connector->hdmi_audio.dai_port)
+		return 0;
+
+	return -EINVAL;
+}
+
+static int drm_connector_hdmi_audio_get_eld(struct device *dev, void *data,
+					    uint8_t *buf, size_t len)
+{
+	struct drm_connector *connector = data;
+
+	mutex_lock(&connector->eld_mutex);
+	memcpy(buf, connector->eld, min(sizeof(connector->eld), len));
+	mutex_unlock(&connector->eld_mutex);
+
+	return 0;
+}
+
+static int drm_connector_hdmi_audio_hook_plugged_cb(struct device *dev,
+						    void *data,
+						    hdmi_codec_plugged_cb fn,
+						    struct device *codec_dev)
+{
+	struct drm_connector *connector = data;
+
+	mutex_lock(&connector->hdmi_audio.lock);
+
+	connector->hdmi_audio.plugged_cb = fn;
+	connector->hdmi_audio.plugged_cb_dev = codec_dev;
+
+	fn(codec_dev, connector->hdmi_audio.last_state);
+
+	mutex_unlock(&connector->hdmi_audio.lock);
+
+	return 0;
+}
+
+void drm_connector_hdmi_audio_plugged_notify(struct drm_connector *connector,
+					     bool plugged)
+{
+	mutex_lock(&connector->hdmi_audio.lock);
+
+	connector->hdmi_audio.last_state = plugged;
+
+	if (connector->hdmi_audio.plugged_cb &&
+	    connector->hdmi_audio.plugged_cb_dev)
+		connector->hdmi_audio.plugged_cb(connector->hdmi_audio.plugged_cb_dev,
+						 connector->hdmi_audio.last_state);
+
+	mutex_unlock(&connector->hdmi_audio.lock);
+}
+EXPORT_SYMBOL(drm_connector_hdmi_audio_plugged_notify);
+
+static const struct hdmi_codec_ops drm_connector_hdmi_audio_ops = {
+	.audio_startup = drm_connector_hdmi_audio_startup,
+	.prepare = drm_connector_hdmi_audio_prepare,
+	.audio_shutdown = drm_connector_hdmi_audio_shutdown,
+	.mute_stream = drm_connector_hdmi_audio_mute_stream,
+	.get_eld = drm_connector_hdmi_audio_get_eld,
+	.get_dai_id = drm_connector_hdmi_audio_get_dai_id,
+	.hook_plugged_cb = drm_connector_hdmi_audio_hook_plugged_cb,
+};
+
+/**
+ * drm_connector_hdmi_audio_init - Initialize HDMI Codec device for the DRM connector
+ * @connector: A pointer to the connector to allocate codec for
+ * @hdmi_codec_dev: device to be used as a parent for the HDMI Codec
+ * @funcs: callbacks for this HDMI Codec
+ * @max_i2s_playback_channels: maximum number of playback I2S channels
+ * @spdif_playback: set if HDMI codec has S/PDIF playback port
+ * @dai_port: sound DAI port, -1 if it is not enabled
+ *
+ * Create a HDMI codec device to be used with the specified connector.
+ *
+ * Returns:
+ * Zero on success, error code on failure.
+ */
+int drm_connector_hdmi_audio_init(struct drm_connector *connector,
+				  struct device *hdmi_codec_dev,
+				  const struct drm_connector_hdmi_audio_funcs *funcs,
+				  unsigned int max_i2s_playback_channels,
+				  bool spdif_playback,
+				  int dai_port)
+{
+	struct hdmi_codec_pdata codec_pdata = {
+		.ops = &drm_connector_hdmi_audio_ops,
+		.max_i2s_channels = max_i2s_playback_channels,
+		.i2s = !!max_i2s_playback_channels,
+		.spdif = spdif_playback,
+		.no_i2s_capture = true,
+		.no_spdif_capture = true,
+		.data = connector,
+	};
+	struct platform_device *pdev;
+
+	if (!funcs ||
+	    !funcs->prepare ||
+	    !funcs->shutdown)
+		return -EINVAL;
+
+	connector->hdmi_audio.funcs = funcs;
+	connector->hdmi_audio.dai_port = dai_port;
+
+	pdev = platform_device_register_data(hdmi_codec_dev,
+					     HDMI_CODEC_DRV_NAME,
+					     PLATFORM_DEVID_AUTO,
+					     &codec_pdata, sizeof(codec_pdata));
+	if (IS_ERR(pdev))
+		return PTR_ERR(pdev);
+
+	connector->hdmi_audio.codec_pdev = pdev;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_connector_hdmi_audio_init);
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index ae6e71305f3000aff1cfe96b050061a300b9478e..1383fa9fff9bcf31488453e209a36c6fe97be2f1 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -33,6 +33,7 @@ 
 #include <drm/drm_sysfs.h>
 #include <drm/drm_utils.h>
 
+#include <linux/platform_device.h>
 #include <linux/property.h>
 #include <linux/uaccess.h>
 
@@ -281,6 +282,7 @@  static int drm_connector_init_only(struct drm_device *dev,
 	mutex_init(&connector->eld_mutex);
 	mutex_init(&connector->edid_override_mutex);
 	mutex_init(&connector->hdmi.infoframes.lock);
+	mutex_init(&connector->hdmi_audio.lock);
 	connector->edid_blob_ptr = NULL;
 	connector->epoch_counter = 0;
 	connector->tile_blob_ptr = NULL;
@@ -714,6 +716,8 @@  void drm_connector_cleanup(struct drm_connector *connector)
 		    DRM_CONNECTOR_REGISTERED))
 		drm_connector_unregister(connector);
 
+	platform_device_unregister(connector->hdmi_audio.codec_pdev);
+
 	if (connector->privacy_screen) {
 		drm_privacy_screen_put(connector->privacy_screen);
 		connector->privacy_screen = NULL;
@@ -750,6 +754,7 @@  void drm_connector_cleanup(struct drm_connector *connector)
 		connector->funcs->atomic_destroy_state(connector,
 						       connector->state);
 
+	mutex_destroy(&connector->hdmi_audio.lock);
 	mutex_destroy(&connector->hdmi.infoframes.lock);
 	mutex_destroy(&connector->mutex);
 
diff --git a/include/drm/display/drm_hdmi_audio_helper.h b/include/drm/display/drm_hdmi_audio_helper.h
new file mode 100644
index 0000000000000000000000000000000000000000..c9a6faef4109f20ba79b610a9d5e8d5980efe2d1
--- /dev/null
+++ b/include/drm/display/drm_hdmi_audio_helper.h
@@ -0,0 +1,22 @@ 
+/* SPDX-License-Identifier: MIT */
+
+#ifndef DRM_DISPLAY_HDMI_AUDIO_HELPER_H_
+#define DRM_DISPLAY_HDMI_AUDIO_HELPER_H_
+
+#include <linux/types.h>
+
+struct drm_connector;
+struct drm_connector_hdmi_audio_funcs;
+
+struct device;
+
+int drm_connector_hdmi_audio_init(struct drm_connector *connector,
+				  struct device *hdmi_codec_dev,
+				  const struct drm_connector_hdmi_audio_funcs *funcs,
+				  unsigned int max_i2s_playback_channels,
+				  bool spdif_playback,
+				  int sound_dai_port);
+void drm_connector_hdmi_audio_plugged_notify(struct drm_connector *connector,
+					     bool plugged);
+
+#endif
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index d1be19242a5c5d7ab6b38cced1da336830b3848d..1d4c27948e8750191e7daf8ff6cda97d944905b4 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -46,6 +46,8 @@  struct drm_property_blob;
 struct drm_printer;
 struct drm_privacy_screen;
 struct edid;
+struct hdmi_codec_daifmt;
+struct hdmi_codec_params;
 struct i2c_adapter;
 
 enum drm_connector_force {
@@ -1141,6 +1143,53 @@  struct drm_connector_state {
 	struct drm_connector_hdmi_state hdmi;
 };
 
+struct drm_connector_hdmi_audio_funcs {
+	/**
+	 * @startup:
+	 *
+	 * Called when ASoC starts an audio stream setup. The
+	 * @startup() is optional.
+	 *
+	 * Returns:
+	 * 0 on success, a negative error code otherwise
+	 */
+	int (*startup)(struct drm_connector *connector);
+
+	/**
+	 * @prepare:
+	 * Configures HDMI-encoder for audio stream. Can be called
+	 * multiple times for each setup. Mandatory.
+	 *
+	 * Returns:
+	 * 0 on success, a negative error code otherwise
+	 */
+	int (*prepare)(struct drm_connector *connector,
+		       struct hdmi_codec_daifmt *fmt,
+		       struct hdmi_codec_params *hparms);
+
+	/**
+	 * @shutdown:
+	 *
+	 * Shut down the audio stream. Mandatory.
+	 *
+	 * Returns:
+	 * 0 on success, a negative error code otherwise
+	 */
+	void (*shutdown)(struct drm_connector *connector);
+
+	/**
+	 * @mute_stream:
+	 *
+	 * Mute/unmute HDMI audio stream. The @mute_stream callback is
+	 * optional.
+	 *
+	 * Returns:
+	 * 0 on success, a negative error code otherwise
+	 */
+	int (*mute_stream)(struct drm_connector *connector,
+			   bool enable, int direction);
+};
+
 /**
  * struct drm_connector_hdmi_funcs - drm_hdmi_connector control functions
  */
@@ -1660,6 +1709,68 @@  struct drm_cmdline_mode {
 	bool tv_mode_specified;
 };
 
+/**
+ * struct drm_connector_hdmi_audio - DRM gemeric HDMI Codec-related structure
+ *
+ * HDMI drivers usually incorporate a HDMI Codec. This structure expresses the
+ * generic HDMI Codec as used by the DRM HDMI Codec framework.
+ */
+struct drm_connector_hdmi_audio {
+	/**
+	 * @funcs:
+	 *
+	 * Implementation of the HDMI codec functionality to be used by the DRM
+	 * HDMI Codec framework.
+	 */
+	const struct drm_connector_hdmi_audio_funcs *funcs;
+
+	/**
+	 * @codec_pdev:
+	 *
+	 * Platform device created to hold the HDMI Codec. It will be
+	 * automatically unregistered during drm_connector_cleanup().
+	 */
+	struct platform_device *codec_pdev;
+
+	/**
+	 * @lock:
+	 *
+	 * Mutex to protect @last_state, @plugged_cb and @plugged_cb_dev.
+	 */
+	struct mutex lock;
+
+	/**
+	 * @plugged_cb:
+	 *
+	 * Callback to be called when the HDMI sink get plugged to or unplugged
+	 * from this connector. This is assigned by the framework when
+	 * requested by the ASoC code.
+	 */
+	void (*plugged_cb)(struct device *dev, bool plugged);
+
+	/**
+	 * @plugged_cb_dev:
+	 *
+	 * The data for @plugged_cb(). It is being provided by the ASoC.
+	 */
+	struct device *plugged_cb_dev;
+
+	/**
+	 * @last_state:
+	 *
+	 * Last plugged state recored by the framework. It is used to correctly
+	 * report the state to @plugged_cb().
+	 */
+	bool last_state;
+
+	/**
+	 * @dai_port:
+	 *
+	 * The port in DT that is used for the Codec DAI.
+	 */
+	int dai_port;
+};
+
 /*
  * struct drm_connector_hdmi - DRM Connector HDMI-related structure
  */
@@ -2121,6 +2232,11 @@  struct drm_connector {
 	 * @hdmi: HDMI-related variable and properties.
 	 */
 	struct drm_connector_hdmi hdmi;
+
+	/**
+	 * @hdmi_audio: HDMI codec properties and non-DRM state.
+	 */
+	struct drm_connector_hdmi_audio hdmi_audio;
 };
 
 #define obj_to_connector(x) container_of(x, struct drm_connector, base)