linux/sound/hda/ext/hdac_ext_stream.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  hdac-ext-stream.c - HD-audio extended stream operations.
 *
 *  Copyright (C) 2015 Intel Corp
 *  Author: Jeeja KP <[email protected]>
 *  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>
#include <linux/slab.h>
#include <sound/pcm.h>
#include <sound/hda_register.h>
#include <sound/hdaudio_ext.h>
#include <sound/compress_driver.h>

/**
 * snd_hdac_ext_host_stream_setup - Setup a HOST stream.
 * @hext_stream: HDAudio stream to set up.
 * @code_loading: Whether the stream is for PCM or code-loading.
 *
 * Return: Zero on success or negative error code.
 */
int snd_hdac_ext_host_stream_setup(struct hdac_ext_stream *hext_stream, bool code_loading)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_apl_host_stream_setup - Setup a HOST stream following procedure
 *                                  recommended for ApolloLake devices.
 * @hstream: HDAudio stream to set up.
 * @code_loading: Whether the stream is for PCM or code-loading.
 *
 * Return: Zero on success or negative error code.
 */
static int snd_hdac_apl_host_stream_setup(struct hdac_stream *hstream, bool code_loading)
{ … }

/**
 * snd_hdac_ext_stream_init - initialize each stream (aka device)
 * @bus: HD-audio core bus
 * @hext_stream: HD-audio ext core stream object to initialize
 * @idx: stream index number
 * @direction: stream direction (SNDRV_PCM_STREAM_PLAYBACK or SNDRV_PCM_STREAM_CAPTURE)
 * @tag: the tag id to assign
 *
 * initialize the stream, if ppcap is enabled then init those and then
 * invoke hdac stream initialization routine
 */
static void snd_hdac_ext_stream_init(struct hdac_bus *bus,
				     struct hdac_ext_stream *hext_stream,
				     int idx, int direction, int tag)
{ … }

/**
 * snd_hdac_ext_stream_init_all - create and initialize the stream objects
 *   for an extended hda bus
 * @bus: HD-audio core bus
 * @start_idx: start index for streams
 * @num_stream: number of streams to initialize
 * @dir: direction of streams
 */
int snd_hdac_ext_stream_init_all(struct hdac_bus *bus, int start_idx,
				 int num_stream, int dir)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_ext_stream_free_all - free hdac extended stream objects
 *
 * @bus: HD-audio core bus
 */
void snd_hdac_ext_stream_free_all(struct hdac_bus *bus)
{ … }
EXPORT_SYMBOL_GPL(…);

void snd_hdac_ext_stream_decouple_locked(struct hdac_bus *bus,
					 struct hdac_ext_stream *hext_stream,
					 bool decouple)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_ext_stream_decouple - decouple the hdac stream
 * @bus: HD-audio core bus
 * @hext_stream: HD-audio ext core stream object to initialize
 * @decouple: flag to decouple
 */
void snd_hdac_ext_stream_decouple(struct hdac_bus *bus,
				  struct hdac_ext_stream *hext_stream, bool decouple)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_ext_stream_start - start a stream
 * @hext_stream: HD-audio ext core stream to start
 */
void snd_hdac_ext_stream_start(struct hdac_ext_stream *hext_stream)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_ext_stream_clear - stop a stream DMA
 * @hext_stream: HD-audio ext core stream to stop
 */
void snd_hdac_ext_stream_clear(struct hdac_ext_stream *hext_stream)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_ext_stream_reset - reset a stream
 * @hext_stream: HD-audio ext core stream to reset
 */
void snd_hdac_ext_stream_reset(struct hdac_ext_stream *hext_stream)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_ext_stream_setup -  set up the SD for streaming
 * @hext_stream: HD-audio ext core stream to set up
 * @fmt: stream format
 */
int snd_hdac_ext_stream_setup(struct hdac_ext_stream *hext_stream, int fmt)
{ … }
EXPORT_SYMBOL_GPL(…);

static struct hdac_ext_stream *
hdac_ext_link_dma_stream_assign(struct hdac_bus *bus,
				struct snd_pcm_substream *substream)
{ … }

static struct hdac_ext_stream *
hdac_ext_host_dma_stream_assign(struct hdac_bus *bus,
				struct snd_pcm_substream *substream)
{ … }

/**
 * snd_hdac_ext_stream_assign - assign a stream for the PCM
 * @bus: HD-audio core bus
 * @substream: PCM substream to assign
 * @type: type of stream (coupled, host or link stream)
 *
 * This assigns the stream based on the type (coupled/host/link), for the
 * given PCM substream, assigns it and returns the stream object
 *
 * coupled: Looks for an unused stream
 * host: Looks for an unused decoupled host stream
 * link: Looks for an unused decoupled link stream
 *
 * If no stream is free, returns NULL. The function tries to keep using
 * the same stream object when it's used beforehand.  when a stream is
 * decoupled, it becomes a host stream and link stream.
 */
struct hdac_ext_stream *snd_hdac_ext_stream_assign(struct hdac_bus *bus,
					   struct snd_pcm_substream *substream,
					   int type)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_ext_stream_release - release the assigned stream
 * @hext_stream: HD-audio ext core stream to release
 * @type: type of stream (coupled, host or link stream)
 *
 * Release the stream that has been assigned by snd_hdac_ext_stream_assign().
 */
void snd_hdac_ext_stream_release(struct hdac_ext_stream *hext_stream, int type)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * snd_hdac_ext_cstream_assign - assign a host stream for compress
 * @bus: HD-audio core bus
 * @cstream: Compress stream to assign
 *
 * Assign an unused host stream for the given compress stream.
 * If no stream is free, NULL is returned. Stream is decoupled
 * before assignment.
 */
struct hdac_ext_stream *snd_hdac_ext_cstream_assign(struct hdac_bus *bus,
						    struct snd_compr_stream *cstream)
{ … }
EXPORT_SYMBOL_GPL(…);