/* SPDX-License-Identifier: GPL-2.0+
   *

   *  Copyright (C) 2012, Analog Devices Inc.
   *	Author: Lars-Peter Clausen <lars@metafoo.de>

   */

  #ifndef __SOUND_DMAENGINE_PCM_H__
  #define __SOUND_DMAENGINE_PCM_H__
  
  #include <sound/pcm.h>

  #include <sound/soc.h>

  #include <linux/dmaengine.h>
  
  /**
   * snd_pcm_substream_to_dma_direction - Get dma_transfer_direction for a PCM
   *   substream
   * @substream: PCM substream
   */
  static inline enum dma_transfer_direction
  snd_pcm_substream_to_dma_direction(const struct snd_pcm_substream *substream)
  {
  	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
  		return DMA_MEM_TO_DEV;
  	else
  		return DMA_DEV_TO_MEM;
  }

  int snd_hwparams_to_dma_slave_config(const struct snd_pcm_substream *substream,
  	const struct snd_pcm_hw_params *params, struct dma_slave_config *slave_config);
  int snd_dmaengine_pcm_trigger(struct snd_pcm_substream *substream, int cmd);

  snd_pcm_uframes_t snd_dmaengine_pcm_pointer(struct snd_pcm_substream *substream);

  snd_pcm_uframes_t snd_dmaengine_pcm_pointer_no_residue(struct snd_pcm_substream *substream);

  
  int snd_dmaengine_pcm_open(struct snd_pcm_substream *substream,

  	struct dma_chan *chan);

  int snd_dmaengine_pcm_close(struct snd_pcm_substream *substream);

  int snd_dmaengine_pcm_open_request_chan(struct snd_pcm_substream *substream,
  	dma_filter_fn filter_fn, void *filter_data);
  int snd_dmaengine_pcm_close_release_chan(struct snd_pcm_substream *substream);

  struct dma_chan *snd_dmaengine_pcm_request_channel(dma_filter_fn filter_fn,
  	void *filter_data);

  struct dma_chan *snd_dmaengine_pcm_get_chan(struct snd_pcm_substream *substream);

  /*
   * The DAI supports packed transfers, eg 2 16-bit samples in a 32-bit word.
   * If this flag is set the dmaengine driver won't put any restriction on
   * the supported sample formats and set the DMA transfer size to undefined.
   * The DAI driver is responsible to disable any unsupported formats in it's
   * configuration and catch corner cases that are not already handled in
   * the ALSA core.
   */
  #define SND_DMAENGINE_PCM_DAI_FLAG_PACK BIT(0)

  /**
   * struct snd_dmaengine_dai_dma_data - DAI DMA configuration data
   * @addr: Address of the DAI data source or destination register.
   * @addr_width: Width of the DAI data source or destination register.
   * @maxburst: Maximum number of words(note: words, as in units of the
   * src_addr_width member, not bytes) that can be send to or received from the
   * DAI in one burst.
   * @slave_id: Slave requester id for the DMA channel.
   * @filter_data: Custom DMA channel filter data, this will usually be used when
   * requesting the DMA channel.

   * @chan_name: Custom channel name to use when requesting DMA channel.

   * @fifo_size: FIFO size of the DAI controller in bytes

   * @flags: PCM_DAI flags, only SND_DMAENGINE_PCM_DAI_FLAG_PACK for now

   */
  struct snd_dmaengine_dai_dma_data {
  	dma_addr_t addr;
  	enum dma_slave_buswidth addr_width;
  	u32 maxburst;
  	unsigned int slave_id;
  	void *filter_data;

  	const char *chan_name;

  	unsigned int fifo_size;

  	unsigned int flags;

  	unsigned int fifo_num;

  };
  
  void snd_dmaengine_pcm_set_config_from_dai_data(
  	const struct snd_pcm_substream *substream,
  	const struct snd_dmaengine_dai_dma_data *dma_data,
  	struct dma_slave_config *config);

  
  /*
   * Try to request the DMA channel using compat_request_channel or
   * compat_filter_fn if it couldn't be requested through devicetree.
   */
  #define SND_DMAENGINE_PCM_FLAG_COMPAT BIT(0)
  /*
   * Don't try to request the DMA channels through devicetree. This flag only
   * makes sense if SND_DMAENGINE_PCM_FLAG_COMPAT is set as well.
   */
  #define SND_DMAENGINE_PCM_FLAG_NO_DT BIT(1)

  /*

   * The PCM is half duplex and the DMA channel is shared between capture and
   * playback.
   */
  #define SND_DMAENGINE_PCM_FLAG_HALF_DUPLEX BIT(3)

  /**
   * struct snd_dmaengine_pcm_config - Configuration data for dmaengine based PCM
   * @prepare_slave_config: Callback used to fill in the DMA slave_config for a
   *   PCM substream. Will be called from the PCM drivers hwparams callback.

   * @compat_request_channel: Callback to request a DMA channel for platforms
   *   which do not use devicetree.

   * @process: Callback used to apply processing on samples transferred from/to
   *   user space.

   * @compat_filter_fn: Will be used as the filter function when requesting a
   *  channel for platforms which do not use devicetree. The filter parameter
   *  will be the DAI's DMA data.

   * @dma_dev: If set, request DMA channel on this device rather than the DAI
   *  device.
   * @chan_names: If set, these custom DMA channel names will be requested at
   *  registration time.

   * @pcm_hardware: snd_pcm_hardware struct to be used for the PCM.
   * @prealloc_buffer_size: Size of the preallocated audio buffer.

   *
   * Note: If both compat_request_channel and compat_filter_fn are set
   * compat_request_channel will be used to request the channel and
   * compat_filter_fn will be ignored. Otherwise the channel will be requested
   * using dma_request_channel with compat_filter_fn as the filter function.

   */
  struct snd_dmaengine_pcm_config {
  	int (*prepare_slave_config)(struct snd_pcm_substream *substream,
  			struct snd_pcm_hw_params *params,
  			struct dma_slave_config *slave_config);

  	struct dma_chan *(*compat_request_channel)(
  			struct snd_soc_pcm_runtime *rtd,
  			struct snd_pcm_substream *substream);

  	int (*process)(struct snd_pcm_substream *substream,
  		       int channel, unsigned long hwoff,
  		       void *buf, unsigned long bytes);

  	dma_filter_fn compat_filter_fn;

  	struct device *dma_dev;
  	const char *chan_names[SNDRV_PCM_STREAM_LAST + 1];

  
  	const struct snd_pcm_hardware *pcm_hardware;
  	unsigned int prealloc_buffer_size;
  };
  
  int snd_dmaengine_pcm_register(struct device *dev,
  	const struct snd_dmaengine_pcm_config *config,
  	unsigned int flags);
  void snd_dmaengine_pcm_unregister(struct device *dev);

  int devm_snd_dmaengine_pcm_register(struct device *dev,
  	const struct snd_dmaengine_pcm_config *config,
  	unsigned int flags);

  int snd_dmaengine_pcm_prepare_slave_config(struct snd_pcm_substream *substream,
  	struct snd_pcm_hw_params *params,
  	struct dma_slave_config *slave_config);

  #define SND_DMAENGINE_PCM_DRV_NAME "snd_dmaengine_pcm"

  #endif