linux/sound/hda/hdac_component.c

// SPDX-License-Identifier: GPL-2.0
// hdac_component.c - routines for sync between HD-A core and DRM driver

#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/component.h>
#include <sound/core.h>
#include <sound/hdaudio.h>
#include <sound/hda_component.h>
#include <sound/hda_register.h>

static void hdac_acomp_release(struct device *dev, void *res)
{ … }

static struct drm_audio_component *hdac_get_acomp(struct device *dev)
{ … }

/**
 * snd_hdac_set_codec_wakeup - Enable / disable HDMI/DP codec wakeup
 * @bus: HDA core bus
 * @enable: enable or disable the wakeup
 *
 * This function is supposed to be used only by a HD-audio controller
 * driver that needs the interaction with graphics driver.
 *
 * This function should be called during the chip reset, also called at
 * resume for updating STATESTS register read.
 *
 * Returns zero for success or a negative error code.
 */
int snd_hdac_set_codec_wakeup(struct hdac_bus *bus, bool enable)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_display_power - Power up / down the power refcount
 * @bus: HDA core bus
 * @idx: HDA codec address, pass HDA_CODEC_IDX_CONTROLLER for controller
 * @enable: power up or down
 *
 * This function is used by either HD-audio controller or codec driver that
 * needs the interaction with graphics driver.
 *
 * This function updates the power status, and calls the get_power() and
 * put_power() ops accordingly, toggling the codec wakeup, too.
 */
void snd_hdac_display_power(struct hdac_bus *bus, unsigned int idx, bool enable)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_sync_audio_rate - Set N/CTS based on the sample rate
 * @codec: HDA codec
 * @nid: the pin widget NID
 * @dev_id: device identifier
 * @rate: the sample rate to set
 *
 * This function is supposed to be used only by a HD-audio controller
 * driver that needs the interaction with graphics driver.
 *
 * This function sets N/CTS value based on the given sample rate.
 * Returns zero for success, or a negative error code.
 */
int snd_hdac_sync_audio_rate(struct hdac_device *codec, hda_nid_t nid,
			     int dev_id, int rate)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_acomp_get_eld - Get the audio state and ELD via component
 * @codec: HDA codec
 * @nid: the pin widget NID
 * @dev_id: device identifier
 * @audio_enabled: the pointer to store the current audio state
 * @buffer: the buffer pointer to store ELD bytes
 * @max_bytes: the max bytes to be stored on @buffer
 *
 * This function is supposed to be used only by a HD-audio controller
 * driver that needs the interaction with graphics driver.
 *
 * This function queries the current state of the audio on the given
 * digital port and fetches the ELD bytes onto the given buffer.
 * It returns the number of bytes for the total ELD data, zero for
 * invalid ELD, or a negative error code.
 *
 * The return size is the total bytes required for the whole ELD bytes,
 * thus it may be over @max_bytes.  If it's over @max_bytes, it implies
 * that only a part of ELD bytes have been fetched.
 */
int snd_hdac_acomp_get_eld(struct hdac_device *codec, hda_nid_t nid, int dev_id,
			   bool *audio_enabled, char *buffer, int max_bytes)
{ … }
EXPORT_SYMBOL_GPL(…);

static int hdac_component_master_bind(struct device *dev)
{ … }

static void hdac_component_master_unbind(struct device *dev)
{ … }

static const struct component_master_ops hdac_component_master_ops = …;

/**
 * snd_hdac_acomp_register_notifier - Register audio component ops
 * @bus: HDA core bus
 * @aops: audio component ops
 *
 * This function is supposed to be used only by a HD-audio controller
 * driver that needs the interaction with graphics driver.
 *
 * This function sets the given ops to be called by the graphics driver.
 *
 * Returns zero for success or a negative error code.
 */
int snd_hdac_acomp_register_notifier(struct hdac_bus *bus,
				    const struct drm_audio_component_audio_ops *aops)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_acomp_init - Initialize audio component
 * @bus: HDA core bus
 * @aops: audio component ops
 * @match_master: match function for finding components
 * @extra_size: Extra bytes to allocate
 *
 * This function is supposed to be used only by a HD-audio controller
 * driver that needs the interaction with graphics driver.
 *
 * This function initializes and sets up the audio component to communicate
 * with graphics driver.
 *
 * Unlike snd_hdac_i915_init(), this function doesn't synchronize with the
 * binding with the DRM component.  Each caller needs to sync via master_bind
 * audio_ops.
 *
 * Returns zero for success or a negative error code.
 */
int snd_hdac_acomp_init(struct hdac_bus *bus,
			const struct drm_audio_component_audio_ops *aops,
			int (*match_master)(struct device *, int, void *),
			size_t extra_size)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_acomp_exit - Finalize audio component
 * @bus: HDA core bus
 *
 * This function is supposed to be used only by a HD-audio controller
 * driver that needs the interaction with graphics driver.
 *
 * This function releases the audio component that has been used.
 *
 * Returns zero for success or a negative error code.
 */
int snd_hdac_acomp_exit(struct hdac_bus *bus)
{ … }
EXPORT_SYMBOL_GPL(…);