321 lines
7.5 KiB
C
321 lines
7.5 KiB
C
|
/*
|
||
|
|
* u_audio.c -- ALSA audio utilities for Gadget stack
|
||
|
|
*
|
||
|
|
* Copyright (C) 2008 Bryan Wu <cooloney@kernel.org>
|
||
|
|
* Copyright (C) 2008 Analog Devices, Inc
|
||
|
|
*
|
||
|
|
* Enter bugs at http://blackfin.uclinux.org/
|
||
|
|
*
|
||
|
|
* Licensed under the GPL-2 or later.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/kernel.h>
|
||
|
|
#include <linux/device.h>
|
||
|
|
#include <linux/delay.h>
|
||
|
|
#include <linux/ctype.h>
|
||
|
|
#include <linux/random.h>
|
||
|
|
#include <linux/syscalls.h>
|
||
|
|
|
||
|
|
#include "u_audio.h"
|
||
|
|
|
||
|
|
/*
|
||
|
|
* This component encapsulates the ALSA devices for USB audio gadget
|
||
|
|
*/
|
||
|
|
|
||
|
|
#define FILE_PCM_PLAYBACK "/dev/snd/pcmC0D0p"
|
||
|
|
#define FILE_PCM_CAPTURE "/dev/snd/pcmC0D0c"
|
||
|
|
#define FILE_CONTROL "/dev/snd/controlC0"
|
||
|
|
|
||
|
|
static char *fn_play = FILE_PCM_PLAYBACK;
|
||
|
|
module_param(fn_play, charp, S_IRUGO);
|
||
|
|
MODULE_PARM_DESC(fn_play, "Playback PCM device file name");
|
||
|
|
|
||
|
|
static char *fn_cap = FILE_PCM_CAPTURE;
|
||
|
|
module_param(fn_cap, charp, S_IRUGO);
|
||
|
|
MODULE_PARM_DESC(fn_cap, "Capture PCM device file name");
|
||
|
|
|
||
|
|
static char *fn_cntl = FILE_CONTROL;
|
||
|
|
module_param(fn_cntl, charp, S_IRUGO);
|
||
|
|
MODULE_PARM_DESC(fn_cntl, "Control device file name");
|
||
|
|
|
||
|
|
/*-------------------------------------------------------------------------*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Some ALSA internal helper functions
|
||
|
|
*/
|
||
|
|
static int snd_interval_refine_set(struct snd_interval *i, unsigned int val)
|
||
|
|
{
|
||
|
|
struct snd_interval t;
|
||
|
|
t.empty = 0;
|
||
|
|
t.min = t.max = val;
|
||
|
|
t.openmin = t.openmax = 0;
|
||
|
|
t.integer = 1;
|
||
|
|
return snd_interval_refine(i, &t);
|
||
|
|
}
|
||
|
|
|
||
|
|
static int _snd_pcm_hw_param_set(struct snd_pcm_hw_params *params,
|
||
|
|
snd_pcm_hw_param_t var, unsigned int val,
|
||
|
|
int dir)
|
||
|
|
{
|
||
|
|
int changed;
|
||
|
|
if (hw_is_mask(var)) {
|
||
|
|
struct snd_mask *m = hw_param_mask(params, var);
|
||
|
|
if (val == 0 && dir < 0) {
|
||
|
|
changed = -EINVAL;
|
||
|
|
snd_mask_none(m);
|
||
|
|
} else {
|
||
|
|
if (dir > 0)
|
||
|
|
val++;
|
||
|
|
else if (dir < 0)
|
||
|
|
val--;
|
||
|
|
changed = snd_mask_refine_set(
|
||
|
|
hw_param_mask(params, var), val);
|
||
|
|
}
|
||
|
|
} else if (hw_is_interval(var)) {
|
||
|
|
struct snd_interval *i = hw_param_interval(params, var);
|
||
|
|
if (val == 0 && dir < 0) {
|
||
|
|
changed = -EINVAL;
|
||
|
|
snd_interval_none(i);
|
||
|
|
} else if (dir == 0)
|
||
|
|
changed = snd_interval_refine_set(i, val);
|
||
|
|
else {
|
||
|
|
struct snd_interval t;
|
||
|
|
t.openmin = 1;
|
||
|
|
t.openmax = 1;
|
||
|
|
t.empty = 0;
|
||
|
|
t.integer = 0;
|
||
|
|
if (dir < 0) {
|
||
|
|
t.min = val - 1;
|
||
|
|
t.max = val;
|
||
|
|
} else {
|
||
|
|
t.min = val;
|
||
|
|
t.max = val+1;
|
||
|
|
}
|
||
|
|
changed = snd_interval_refine(i, &t);
|
||
|
|
}
|
||
|
|
} else
|
||
|
|
return -EINVAL;
|
||
|
|
if (changed) {
|
||
|
|
params->cmask |= 1 << var;
|
||
|
|
params->rmask |= 1 << var;
|
||
|
|
}
|
||
|
|
return changed;
|
||
|
|
}
|
||
|
|
/*-------------------------------------------------------------------------*/
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Set default hardware params
|
||
|
|
*/
|
||
|
|
static int playback_default_hw_params(struct gaudio_snd_dev *snd)
|
||
|
|
{
|
||
|
|
struct snd_pcm_substream *substream = snd->substream;
|
||
|
|
struct snd_pcm_hw_params *params;
|
||
|
|
snd_pcm_sframes_t result;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* SNDRV_PCM_ACCESS_RW_INTERLEAVED,
|
||
|
|
* SNDRV_PCM_FORMAT_S16_LE
|
||
|
|
* CHANNELS: 2
|
||
|
|
* RATE: 48000
|
||
|
|
*/
|
||
|
|
snd->access = SNDRV_PCM_ACCESS_RW_INTERLEAVED;
|
||
|
|
snd->format = SNDRV_PCM_FORMAT_S16_LE;
|
||
|
|
snd->channels = 2;
|
||
|
|
snd->rate = 48000;
|
||
|
|
|
||
|
|
params = kzalloc(sizeof(*params), GFP_KERNEL);
|
||
|
|
if (!params)
|
||
|
|
return -ENOMEM;
|
||
|
|
|
||
|
|
_snd_pcm_hw_params_any(params);
|
||
|
|
_snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_ACCESS,
|
||
|
|
snd->access, 0);
|
||
|
|
_snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_FORMAT,
|
||
|
|
snd->format, 0);
|
||
|
|
_snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_CHANNELS,
|
||
|
|
snd->channels, 0);
|
||
|
|
_snd_pcm_hw_param_set(params, SNDRV_PCM_HW_PARAM_RATE,
|
||
|
|
snd->rate, 0);
|
||
|
|
|
||
|
|
snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_DROP, NULL);
|
||
|
|
snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_HW_PARAMS, params);
|
||
|
|
|
||
|
|
result = snd_pcm_kernel_ioctl(substream, SNDRV_PCM_IOCTL_PREPARE, NULL);
|
||
|
|
if (result < 0) {
|
||
|
|
ERROR(snd->card,
|
||
|
|
"Preparing sound card failed: %d\n", (int)result);
|
||
|
|
kfree(params);
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
/* Store the hardware parameters */
|
||
|
|
snd->access = params_access(params);
|
||
|
|
snd->format = params_format(params);
|
||
|
|
snd->channels = params_channels(params);
|
||
|
|
snd->rate = params_rate(params);
|
||
|
|
|
||
|
|
kfree(params);
|
||
|
|
|
||
|
|
INFO(snd->card,
|
||
|
|
"Hardware params: access %x, format %x, channels %d, rate %d\n",
|
||
|
|
snd->access, snd->format, snd->channels, snd->rate);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Playback audio buffer data by ALSA PCM device
|
||
|
|
*/
|
||
|
|
static size_t u_audio_playback(struct gaudio *card, void *buf, size_t count)
|
||
|
|
{
|
||
|
|
struct gaudio_snd_dev *snd = &card->playback;
|
||
|
|
struct snd_pcm_substream *substream = snd->substream;
|
||
|
|
struct snd_pcm_runtime *runtime = substream->runtime;
|
||
|
|
mm_segment_t old_fs;
|
||
|
|
ssize_t result;
|
||
|
|
snd_pcm_sframes_t frames;
|
||
|
|
|
||
|
|
try_again:
|
||
|
|
if (runtime->status->state == SNDRV_PCM_STATE_XRUN ||
|
||
|
|
runtime->status->state == SNDRV_PCM_STATE_SUSPENDED) {
|
||
|
|
result = snd_pcm_kernel_ioctl(substream,
|
||
|
|
SNDRV_PCM_IOCTL_PREPARE, NULL);
|
||
|
|
if (result < 0) {
|
||
|
|
ERROR(card, "Preparing sound card failed: %d\n",
|
||
|
|
(int)result);
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
frames = bytes_to_frames(runtime, count);
|
||
|
|
old_fs = get_fs();
|
||
|
|
set_fs(KERNEL_DS);
|
||
|
|
result = snd_pcm_lib_write(snd->substream, buf, frames);
|
||
|
|
if (result != frames) {
|
||
|
|
ERROR(card, "Playback error: %d\n", (int)result);
|
||
|
|
set_fs(old_fs);
|
||
|
|
goto try_again;
|
||
|
|
}
|
||
|
|
set_fs(old_fs);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int u_audio_get_playback_channels(struct gaudio *card)
|
||
|
|
{
|
||
|
|
return card->playback.channels;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int u_audio_get_playback_rate(struct gaudio *card)
|
||
|
|
{
|
||
|
|
return card->playback.rate;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Open ALSA PCM and control device files
|
||
|
|
* Initial the PCM or control device
|
||
|
|
*/
|
||
|
|
static int gaudio_open_snd_dev(struct gaudio *card)
|
||
|
|
{
|
||
|
|
struct snd_pcm_file *pcm_file;
|
||
|
|
struct gaudio_snd_dev *snd;
|
||
|
|
|
||
|
|
if (!card)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
/* Open control device */
|
||
|
|
snd = &card->control;
|
||
|
|
snd->filp = filp_open(fn_cntl, O_RDWR, 0);
|
||
|
|
if (IS_ERR(snd->filp)) {
|
||
|
|
int ret = PTR_ERR(snd->filp);
|
||
|
|
ERROR(card, "unable to open sound control device file: %s\n",
|
||
|
|
fn_cntl);
|
||
|
|
snd->filp = NULL;
|
||
|
|
return ret;
|
||
|
|
}
|
||
|
|
snd->card = card;
|
||
|
|
|
||
|
|
/* Open PCM playback device and setup substream */
|
||
|
|
snd = &card->playback;
|
||
|
|
snd->filp = filp_open(fn_play, O_WRONLY, 0);
|
||
|
|
if (IS_ERR(snd->filp)) {
|
||
|
|
ERROR(card, "No such PCM playback device: %s\n", fn_play);
|
||
|
|
snd->filp = NULL;
|
||
|
|
}
|
||
|
|
pcm_file = snd->filp->private_data;
|
||
|
|
snd->substream = pcm_file->substream;
|
||
|
|
snd->card = card;
|
||
|
|
playback_default_hw_params(snd);
|
||
|
|
|
||
|
|
/* Open PCM capture device and setup substream */
|
||
|
|
snd = &card->capture;
|
||
|
|
snd->filp = filp_open(fn_cap, O_RDONLY, 0);
|
||
|
|
if (IS_ERR(snd->filp)) {
|
||
|
|
ERROR(card, "No such PCM capture device: %s\n", fn_cap);
|
||
|
|
snd->substream = NULL;
|
||
|
|
snd->card = NULL;
|
||
|
|
} else {
|
||
|
|
pcm_file = snd->filp->private_data;
|
||
|
|
snd->substream = pcm_file->substream;
|
||
|
|
snd->card = card;
|
||
|
|
}
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Close ALSA PCM and control device files
|
||
|
|
*/
|
||
|
|
static int gaudio_close_snd_dev(struct gaudio *gau)
|
||
|
|
{
|
||
|
|
struct gaudio_snd_dev *snd;
|
||
|
|
|
||
|
|
/* Close control device */
|
||
|
|
snd = &gau->control;
|
||
|
|
if (!IS_ERR(snd->filp))
|
||
|
|
filp_close(snd->filp, current->files);
|
||
|
|
|
||
|
|
/* Close PCM playback device and setup substream */
|
||
|
|
snd = &gau->playback;
|
||
|
|
if (!IS_ERR(snd->filp))
|
||
|
|
filp_close(snd->filp, current->files);
|
||
|
|
|
||
|
|
/* Close PCM capture device and setup substream */
|
||
|
|
snd = &gau->capture;
|
||
|
|
if (!IS_ERR(snd->filp))
|
||
|
|
filp_close(snd->filp, current->files);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* gaudio_setup - setup ALSA interface and preparing for USB transfer
|
||
|
|
*
|
||
|
|
* This sets up PCM, mixer or MIDI ALSA devices fore USB gadget using.
|
||
|
|
*
|
||
|
|
* Returns negative errno, or zero on success
|
||
|
|
*/
|
||
|
|
int __init gaudio_setup(struct gaudio *card)
|
||
|
|
{
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ret = gaudio_open_snd_dev(card);
|
||
|
|
if (ret)
|
||
|
|
ERROR(card, "we need at least one control device\n");
|
||
|
|
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* gaudio_cleanup - remove ALSA device interface
|
||
|
|
*
|
||
|
|
* This is called to free all resources allocated by @gaudio_setup().
|
||
|
|
*/
|
||
|
|
void gaudio_cleanup(struct gaudio *card)
|
||
|
|
{
|
||
|
|
if (card)
|
||
|
|
gaudio_close_snd_dev(card);
|
||
|
|
}
|
||
|
|
|