+++ /dev/null
-/*
- * sound.c - Audio Application Interface Module for Mostcore
- *
- * Copyright (C) 2015 Microchip Technology Germany II GmbH & Co. KG
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * This file is licensed under GPLv2.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/module.h>
-#include <linux/printk.h>
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <sound/core.h>
-#include <sound/pcm.h>
-#include <sound/pcm_params.h>
-#include <linux/sched.h>
-#include <linux/kthread.h>
-#include <mostcore.h>
-
-#define DRIVER_NAME "sound"
-
-static struct list_head dev_list;
-static struct most_aim audio_aim;
-
-/**
- * struct channel - private structure to keep channel specific data
- * @substream: stores the substream structure
- * @iface: interface for which the channel belongs to
- * @cfg: channel configuration
- * @card: registered sound card
- * @list: list for private use
- * @id: channel index
- * @period_pos: current period position (ring buffer)
- * @buffer_pos: current buffer position (ring buffer)
- * @is_stream_running: identifies whether a stream is running or not
- * @opened: set when the stream is opened
- * @playback_task: playback thread
- * @playback_waitq: waitq used by playback thread
- */
-struct channel {
- struct snd_pcm_substream *substream;
- struct snd_pcm_hardware pcm_hardware;
- struct most_interface *iface;
- struct most_channel_config *cfg;
- struct snd_card *card;
- struct list_head list;
- int id;
- unsigned int period_pos;
- unsigned int buffer_pos;
- bool is_stream_running;
-
- struct task_struct *playback_task;
- wait_queue_head_t playback_waitq;
-
- void (*copy_fn)(void *alsa, void *most, unsigned int bytes);
-};
-
-#define MOST_PCM_INFO (SNDRV_PCM_INFO_MMAP | \
- SNDRV_PCM_INFO_MMAP_VALID | \
- SNDRV_PCM_INFO_BATCH | \
- SNDRV_PCM_INFO_INTERLEAVED | \
- SNDRV_PCM_INFO_BLOCK_TRANSFER)
-
-#define swap16(val) ( \
- (((u16)(val) << 8) & (u16)0xFF00) | \
- (((u16)(val) >> 8) & (u16)0x00FF))
-
-#define swap32(val) ( \
- (((u32)(val) << 24) & (u32)0xFF000000) | \
- (((u32)(val) << 8) & (u32)0x00FF0000) | \
- (((u32)(val) >> 8) & (u32)0x0000FF00) | \
- (((u32)(val) >> 24) & (u32)0x000000FF))
-
-static void swap_copy16(u16 *dest, const u16 *source, unsigned int bytes)
-{
- unsigned int i = 0;
-
- while (i < (bytes / 2)) {
- dest[i] = swap16(source[i]);
- i++;
- }
-}
-
-static void swap_copy24(u8 *dest, const u8 *source, unsigned int bytes)
-{
- unsigned int i = 0;
-
- while (i < bytes - 2) {
- dest[i] = source[i + 2];
- dest[i + 1] = source[i + 1];
- dest[i + 2] = source[i];
- i += 3;
- }
-}
-
-static void swap_copy32(u32 *dest, const u32 *source, unsigned int bytes)
-{
- unsigned int i = 0;
-
- while (i < bytes / 4) {
- dest[i] = swap32(source[i]);
- i++;
- }
-}
-
-static void alsa_to_most_memcpy(void *alsa, void *most, unsigned int bytes)
-{
- memcpy(most, alsa, bytes);
-}
-
-static void alsa_to_most_copy16(void *alsa, void *most, unsigned int bytes)
-{
- swap_copy16(most, alsa, bytes);
-}
-
-static void alsa_to_most_copy24(void *alsa, void *most, unsigned int bytes)
-{
- swap_copy24(most, alsa, bytes);
-}
-
-static void alsa_to_most_copy32(void *alsa, void *most, unsigned int bytes)
-{
- swap_copy32(most, alsa, bytes);
-}
-
-static void most_to_alsa_memcpy(void *alsa, void *most, unsigned int bytes)
-{
- memcpy(alsa, most, bytes);
-}
-
-static void most_to_alsa_copy16(void *alsa, void *most, unsigned int bytes)
-{
- swap_copy16(alsa, most, bytes);
-}
-
-static void most_to_alsa_copy24(void *alsa, void *most, unsigned int bytes)
-{
- swap_copy24(alsa, most, bytes);
-}
-
-static void most_to_alsa_copy32(void *alsa, void *most, unsigned int bytes)
-{
- swap_copy32(alsa, most, bytes);
-}
-
-/**
- * get_channel - get pointer to channel
- * @iface: interface structure
- * @channel_id: channel ID
- *
- * This traverses the channel list and returns the channel matching the
- * ID and interface.
- *
- * Returns pointer to channel on success or NULL otherwise.
- */
-static struct channel *get_channel(struct most_interface *iface,
- int channel_id)
-{
- struct channel *channel, *tmp;
-
- list_for_each_entry_safe(channel, tmp, &dev_list, list) {
- if ((channel->iface == iface) && (channel->id == channel_id))
- return channel;
- }
-
- return NULL;
-}
-
-/**
- * copy_data - implements data copying function
- * @channel: channel
- * @mbo: MBO from core
- *
- * Copy data from/to ring buffer to/from MBO and update the buffer position
- */
-static bool copy_data(struct channel *channel, struct mbo *mbo)
-{
- struct snd_pcm_runtime *const runtime = channel->substream->runtime;
- unsigned int const frame_bytes = channel->cfg->subbuffer_size;
- unsigned int const buffer_size = runtime->buffer_size;
- unsigned int frames;
- unsigned int fr0;
-
- if (channel->cfg->direction & MOST_CH_RX)
- frames = mbo->processed_length / frame_bytes;
- else
- frames = mbo->buffer_length / frame_bytes;
- fr0 = min(buffer_size - channel->buffer_pos, frames);
-
- channel->copy_fn(runtime->dma_area + channel->buffer_pos * frame_bytes,
- mbo->virt_address,
- fr0 * frame_bytes);
-
- if (frames > fr0) {
- /* wrap around at end of ring buffer */
- channel->copy_fn(runtime->dma_area,
- mbo->virt_address + fr0 * frame_bytes,
- (frames - fr0) * frame_bytes);
- }
-
- channel->buffer_pos += frames;
- if (channel->buffer_pos >= buffer_size)
- channel->buffer_pos -= buffer_size;
- channel->period_pos += frames;
- if (channel->period_pos >= runtime->period_size) {
- channel->period_pos -= runtime->period_size;
- return true;
- }
-
- return false;
-}
-
-/**
- * playback_thread - function implements the playback thread
- * @data: private data
- *
- * Thread which does the playback functionality in a loop. It waits for a free
- * MBO from mostcore for a particular channel and copy the data from ring buffer
- * to MBO. Submit the MBO back to mostcore, after copying the data.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int playback_thread(void *data)
-{
- struct channel *const channel = data;
-
- while (!kthread_should_stop()) {
- struct mbo *mbo = NULL;
- bool period_elapsed = false;
- int ret;
-
- wait_event_interruptible(
- channel->playback_waitq,
- kthread_should_stop() ||
- (channel->is_stream_running &&
- (mbo = most_get_mbo(channel->iface, channel->id,
- &audio_aim))));
- if (!mbo)
- continue;
-
- if (channel->is_stream_running)
- period_elapsed = copy_data(channel, mbo);
- else
- memset(mbo->virt_address, 0, mbo->buffer_length);
-
- ret = most_submit_mbo(mbo);
- if (ret)
- channel->is_stream_running = false;
-
- if (period_elapsed)
- snd_pcm_period_elapsed(channel->substream);
- }
-
- return 0;
-}
-
-/**
- * pcm_open - implements open callback function for PCM middle layer
- * @substream: pointer to ALSA PCM substream
- *
- * This is called when a PCM substream is opened. At least, the function should
- * initialize the runtime->hw record.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int pcm_open(struct snd_pcm_substream *substream)
-{
- struct channel *channel = substream->private_data;
- struct snd_pcm_runtime *runtime = substream->runtime;
- struct most_channel_config *cfg = channel->cfg;
-
- channel->substream = substream;
-
- if (cfg->direction == MOST_CH_TX) {
- channel->playback_task = kthread_run(playback_thread, channel,
- "most_audio_playback");
- if (IS_ERR(channel->playback_task)) {
- pr_err("Couldn't start thread\n");
- return PTR_ERR(channel->playback_task);
- }
- }
-
- if (most_start_channel(channel->iface, channel->id, &audio_aim)) {
- pr_err("most_start_channel() failed!\n");
- if (cfg->direction == MOST_CH_TX)
- kthread_stop(channel->playback_task);
- return -EBUSY;
- }
-
- runtime->hw = channel->pcm_hardware;
- return 0;
-}
-
-/**
- * pcm_close - implements close callback function for PCM middle layer
- * @substream: sub-stream pointer
- *
- * Obviously, this is called when a PCM substream is closed. Any private
- * instance for a PCM substream allocated in the open callback will be
- * released here.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int pcm_close(struct snd_pcm_substream *substream)
-{
- struct channel *channel = substream->private_data;
-
- if (channel->cfg->direction == MOST_CH_TX)
- kthread_stop(channel->playback_task);
- most_stop_channel(channel->iface, channel->id, &audio_aim);
-
- return 0;
-}
-
-/**
- * pcm_hw_params - implements hw_params callback function for PCM middle layer
- * @substream: sub-stream pointer
- * @hw_params: contains the hardware parameters set by the application
- *
- * This is called when the hardware parameters is set by the application, that
- * is, once when the buffer size, the period size, the format, etc. are defined
- * for the PCM substream. Many hardware setups should be done is this callback,
- * including the allocation of buffers.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int pcm_hw_params(struct snd_pcm_substream *substream,
- struct snd_pcm_hw_params *hw_params)
-{
- struct channel *channel = substream->private_data;
-
- if ((params_channels(hw_params) > channel->pcm_hardware.channels_max) ||
- (params_channels(hw_params) < channel->pcm_hardware.channels_min)) {
- pr_err("Requested number of channels not supported.\n");
- return -EINVAL;
- }
- return snd_pcm_lib_alloc_vmalloc_buffer(substream,
- params_buffer_bytes(hw_params));
-}
-
-/**
- * pcm_hw_free - implements hw_free callback function for PCM middle layer
- * @substream: substream pointer
- *
- * This is called to release the resources allocated via hw_params.
- * This function will be always called before the close callback is called.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int pcm_hw_free(struct snd_pcm_substream *substream)
-{
- return snd_pcm_lib_free_vmalloc_buffer(substream);
-}
-
-/**
- * pcm_prepare - implements prepare callback function for PCM middle layer
- * @substream: substream pointer
- *
- * This callback is called when the PCM is "prepared". Format rate, sample rate,
- * etc., can be set here. This callback can be called many times at each setup.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int pcm_prepare(struct snd_pcm_substream *substream)
-{
- struct channel *channel = substream->private_data;
- struct snd_pcm_runtime *runtime = substream->runtime;
- struct most_channel_config *cfg = channel->cfg;
- int width = snd_pcm_format_physical_width(runtime->format);
-
- channel->copy_fn = NULL;
-
- if (cfg->direction == MOST_CH_TX) {
- if (snd_pcm_format_big_endian(runtime->format) || width == 8)
- channel->copy_fn = alsa_to_most_memcpy;
- else if (width == 16)
- channel->copy_fn = alsa_to_most_copy16;
- else if (width == 24)
- channel->copy_fn = alsa_to_most_copy24;
- else if (width == 32)
- channel->copy_fn = alsa_to_most_copy32;
- } else {
- if (snd_pcm_format_big_endian(runtime->format) || width == 8)
- channel->copy_fn = most_to_alsa_memcpy;
- else if (width == 16)
- channel->copy_fn = most_to_alsa_copy16;
- else if (width == 24)
- channel->copy_fn = most_to_alsa_copy24;
- else if (width == 32)
- channel->copy_fn = most_to_alsa_copy32;
- }
-
- if (!channel->copy_fn) {
- pr_err("unsupported format\n");
- return -EINVAL;
- }
-
- channel->period_pos = 0;
- channel->buffer_pos = 0;
-
- return 0;
-}
-
-/**
- * pcm_trigger - implements trigger callback function for PCM middle layer
- * @substream: substream pointer
- * @cmd: action to perform
- *
- * This is called when the PCM is started, stopped or paused. The action will be
- * specified in the second argument, SNDRV_PCM_TRIGGER_XXX
- *
- * Returns 0 on success or error code otherwise.
- */
-static int pcm_trigger(struct snd_pcm_substream *substream, int cmd)
-{
- struct channel *channel = substream->private_data;
-
- switch (cmd) {
- case SNDRV_PCM_TRIGGER_START:
- channel->is_stream_running = true;
- wake_up_interruptible(&channel->playback_waitq);
- return 0;
-
- case SNDRV_PCM_TRIGGER_STOP:
- channel->is_stream_running = false;
- return 0;
-
- default:
- pr_info("pcm_trigger(), invalid\n");
- return -EINVAL;
- }
- return 0;
-}
-
-/**
- * pcm_pointer - implements pointer callback function for PCM middle layer
- * @substream: substream pointer
- *
- * This callback is called when the PCM middle layer inquires the current
- * hardware position on the buffer. The position must be returned in frames,
- * ranging from 0 to buffer_size-1.
- */
-static snd_pcm_uframes_t pcm_pointer(struct snd_pcm_substream *substream)
-{
- struct channel *channel = substream->private_data;
-
- return channel->buffer_pos;
-}
-
-/**
- * Initialization of struct snd_pcm_ops
- */
-static struct snd_pcm_ops pcm_ops = {
- .open = pcm_open,
- .close = pcm_close,
- .ioctl = snd_pcm_lib_ioctl,
- .hw_params = pcm_hw_params,
- .hw_free = pcm_hw_free,
- .prepare = pcm_prepare,
- .trigger = pcm_trigger,
- .pointer = pcm_pointer,
- .page = snd_pcm_lib_get_vmalloc_page,
- .mmap = snd_pcm_lib_mmap_vmalloc,
-};
-
-static int split_arg_list(char *buf, char **card_name, char **pcm_format)
-{
- *card_name = strsep(&buf, ".");
- if (!*card_name)
- return -EIO;
- *pcm_format = strsep(&buf, ".\n");
- if (!*pcm_format)
- return -EIO;
- return 0;
-}
-
-static int audio_set_hw_params(struct snd_pcm_hardware *pcm_hw,
- char *pcm_format,
- struct most_channel_config *cfg)
-{
- pcm_hw->info = MOST_PCM_INFO;
- pcm_hw->rates = SNDRV_PCM_RATE_48000;
- pcm_hw->rate_min = 48000;
- pcm_hw->rate_max = 48000;
- pcm_hw->buffer_bytes_max = cfg->num_buffers * cfg->buffer_size;
- pcm_hw->period_bytes_min = cfg->buffer_size;
- pcm_hw->period_bytes_max = cfg->buffer_size;
- pcm_hw->periods_min = 1;
- pcm_hw->periods_max = cfg->num_buffers;
-
- if (!strcmp(pcm_format, "1x8")) {
- if (cfg->subbuffer_size != 1)
- goto error;
- pr_info("PCM format is 8-bit mono\n");
- pcm_hw->channels_min = 1;
- pcm_hw->channels_max = 1;
- pcm_hw->formats = SNDRV_PCM_FMTBIT_S8;
- } else if (!strcmp(pcm_format, "2x16")) {
- if (cfg->subbuffer_size != 4)
- goto error;
- pr_info("PCM format is 16-bit stereo\n");
- pcm_hw->channels_min = 2;
- pcm_hw->channels_max = 2;
- pcm_hw->formats = SNDRV_PCM_FMTBIT_S16_LE |
- SNDRV_PCM_FMTBIT_S16_BE;
- } else if (!strcmp(pcm_format, "2x24")) {
- if (cfg->subbuffer_size != 6)
- goto error;
- pr_info("PCM format is 24-bit stereo\n");
- pcm_hw->channels_min = 2;
- pcm_hw->channels_max = 2;
- pcm_hw->formats = SNDRV_PCM_FMTBIT_S24_3LE |
- SNDRV_PCM_FMTBIT_S24_3BE;
- } else if (!strcmp(pcm_format, "2x32")) {
- if (cfg->subbuffer_size != 8)
- goto error;
- pr_info("PCM format is 32-bit stereo\n");
- pcm_hw->channels_min = 2;
- pcm_hw->channels_max = 2;
- pcm_hw->formats = SNDRV_PCM_FMTBIT_S32_LE |
- SNDRV_PCM_FMTBIT_S32_BE;
- } else if (!strcmp(pcm_format, "6x16")) {
- if (cfg->subbuffer_size != 12)
- goto error;
- pr_info("PCM format is 16-bit 5.1 multi channel\n");
- pcm_hw->channels_min = 6;
- pcm_hw->channels_max = 6;
- pcm_hw->formats = SNDRV_PCM_FMTBIT_S16_LE |
- SNDRV_PCM_FMTBIT_S16_BE;
- } else {
- pr_err("PCM format %s not supported\n", pcm_format);
- return -EIO;
- }
- return 0;
-error:
- pr_err("Audio resolution doesn't fit subbuffer size\n");
- return -EINVAL;
-}
-
-/**
- * audio_probe_channel - probe function of the driver module
- * @iface: pointer to interface instance
- * @channel_id: channel index/ID
- * @cfg: pointer to actual channel configuration
- * @parent: pointer to kobject (needed for sysfs hook-up)
- * @arg_list: string that provides the name of the device to be created in /dev
- * plus the desired audio resolution
- *
- * Creates sound card, pcm device, sets pcm ops and registers sound card.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int audio_probe_channel(struct most_interface *iface, int channel_id,
- struct most_channel_config *cfg,
- struct kobject *parent, char *arg_list)
-{
- struct channel *channel;
- struct snd_card *card;
- struct snd_pcm *pcm;
- int playback_count = 0;
- int capture_count = 0;
- int ret;
- int direction;
- char *card_name;
- char *pcm_format;
-
- if (!iface)
- return -EINVAL;
-
- if (cfg->data_type != MOST_CH_SYNC) {
- pr_err("Incompatible channel type\n");
- return -EINVAL;
- }
-
- if (get_channel(iface, channel_id)) {
- pr_err("channel (%s:%d) is already linked\n",
- iface->description, channel_id);
- return -EINVAL;
- }
-
- if (cfg->direction == MOST_CH_TX) {
- playback_count = 1;
- direction = SNDRV_PCM_STREAM_PLAYBACK;
- } else {
- capture_count = 1;
- direction = SNDRV_PCM_STREAM_CAPTURE;
- }
-
- ret = split_arg_list(arg_list, &card_name, &pcm_format);
- if (ret < 0) {
- pr_info("PCM format missing\n");
- return ret;
- }
-
- ret = snd_card_create(-1, card_name, THIS_MODULE,
-- sizeof(*channel), &card);
- if (ret < 0)
- return ret;
-
- channel = card->private_data;
- channel->card = card;
- channel->cfg = cfg;
- channel->iface = iface;
- channel->id = channel_id;
- init_waitqueue_head(&channel->playback_waitq);
-
- if (audio_set_hw_params(&channel->pcm_hardware, pcm_format, cfg))
- goto err_free_card;
-
- snprintf(card->driver, sizeof(card->driver), "%s", DRIVER_NAME);
- snprintf(card->shortname, sizeof(card->shortname), "Microchip MOST:%d",
- card->number);
- snprintf(card->longname, sizeof(card->longname), "%s at %s, ch %d",
- card->shortname, iface->description, channel_id);
-
- ret = snd_pcm_new(card, card_name, 0, playback_count,
- capture_count, &pcm);
- if (ret < 0)
- goto err_free_card;
-
- pcm->private_data = channel;
-
- snd_pcm_set_ops(pcm, direction, &pcm_ops);
-
- ret = snd_card_register(card);
- if (ret < 0)
- goto err_free_card;
-
- list_add_tail(&channel->list, &dev_list);
-
- return 0;
-
-err_free_card:
- snd_card_free(card);
- return ret;
-}
-
-/**
- * audio_disconnect_channel - function to disconnect a channel
- * @iface: pointer to interface instance
- * @channel_id: channel index
- *
- * This frees allocated memory and removes the sound card from ALSA
- *
- * Returns 0 on success or error code otherwise.
- */
-static int audio_disconnect_channel(struct most_interface *iface,
- int channel_id)
-{
- struct channel *channel;
-
- channel = get_channel(iface, channel_id);
- if (!channel) {
- pr_err("sound_disconnect_channel(), invalid channel %d\n",
- channel_id);
- return -EINVAL;
- }
-
- list_del(&channel->list);
- snd_card_free(channel->card);
-
- return 0;
-}
-
-/**
- * audio_rx_completion - completion handler for rx channels
- * @mbo: pointer to buffer object that has completed
- *
- * This searches for the channel this MBO belongs to and copy the data from MBO
- * to ring buffer
- *
- * Returns 0 on success or error code otherwise.
- */
-static int audio_rx_completion(struct mbo *mbo)
-{
- struct channel *channel = get_channel(mbo->ifp, mbo->hdm_channel_id);
- bool period_elapsed = false;
-
- if (!channel) {
- pr_err("sound_rx_completion(), invalid channel %d\n",
- mbo->hdm_channel_id);
- return -EINVAL;
- }
-
- if (channel->is_stream_running)
- period_elapsed = copy_data(channel, mbo);
-
- most_put_mbo(mbo);
-
- if (period_elapsed)
- snd_pcm_period_elapsed(channel->substream);
-
- return 0;
-}
-
-/**
- * audio_tx_completion - completion handler for tx channels
- * @iface: pointer to interface instance
- * @channel_id: channel index/ID
- *
- * This searches the channel that belongs to this combination of interface
- * pointer and channel ID and wakes a process sitting in the wait queue of
- * this channel.
- *
- * Returns 0 on success or error code otherwise.
- */
-static int audio_tx_completion(struct most_interface *iface, int channel_id)
-{
- struct channel *channel = get_channel(iface, channel_id);
-
- if (!channel) {
- pr_err("sound_tx_completion(), invalid channel %d\n",
- channel_id);
- return -EINVAL;
- }
-
- wake_up_interruptible(&channel->playback_waitq);
-
- return 0;
-}
-
-/**
- * Initialization of the struct most_aim
- */
-static struct most_aim audio_aim = {
- .name = DRIVER_NAME,
- .probe_channel = audio_probe_channel,
- .disconnect_channel = audio_disconnect_channel,
- .rx_completion = audio_rx_completion,
- .tx_completion = audio_tx_completion,
-};
-
-static int __init audio_init(void)
-{
- pr_info("init()\n");
-
- INIT_LIST_HEAD(&dev_list);
-
- return most_register_aim(&audio_aim);
-}
-
-static void __exit audio_exit(void)
-{
- struct channel *channel, *tmp;
-
- pr_info("exit()\n");
-
- list_for_each_entry_safe(channel, tmp, &dev_list, list) {
- list_del(&channel->list);
- snd_card_free(channel->card);
- }
-
- most_deregister_aim(&audio_aim);
-}
-
-module_init(audio_init);
-module_exit(audio_exit);
-
-MODULE_LICENSE("GPL");
-MODULE_AUTHOR("Christian Gromm <christian.gromm@microchip.com>");
-MODULE_DESCRIPTION("Audio Application Interface Module for MostCore");
Code Review / AGL / meta-agl-demo.git / blobdiff