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/*
* Line6 Linux USB driver - 0.9.1beta
*
* Copyright (C) 2004-2010 Markus Grabner (grabner@icg.tugraz.at)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation, version 2.
*
*/
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include "audio.h"
#include "capture.h"
#include "driver.h"
#include "pcm.h"
#include "playback.h"
/*
Software stereo volume control.
*/
static void change_volume(struct urb *urb_out, int volume[],
int bytes_per_frame)
{
int chn = 0;
if (volume[0] == 256 && volume[1] == 256)
return; /* maximum volume - no change */
if (bytes_per_frame == 4) {
short *p, *buf_end;
p = (short *)urb_out->transfer_buffer;
buf_end = p + urb_out->transfer_buffer_length / sizeof(*p);
for (; p < buf_end; ++p) {
*p = (*p * volume[chn & 1]) >> 8;
++chn;
}
} else if (bytes_per_frame == 6) {
unsigned char *p, *buf_end;
p = (unsigned char *)urb_out->transfer_buffer;
buf_end = p + urb_out->transfer_buffer_length;
for (; p < buf_end; p += 3) {
int val;
val = p[0] + (p[1] << 8) + ((signed char)p[2] << 16);
val = (val * volume[chn & 1]) >> 8;
p[0] = val;
p[1] = val >> 8;
p[2] = val >> 16;
++chn;
}
}
}
/*
Create signal for impulse response test.
*/
static void create_impulse_test_signal(struct snd_line6_pcm *line6pcm,
struct urb *urb_out, int bytes_per_frame)
{
int frames = urb_out->transfer_buffer_length / bytes_per_frame;
if (bytes_per_frame == 4) {
int i;
short *pi = (short *)line6pcm->prev_fbuf;
short *po = (short *)urb_out->transfer_buffer;
for (i = 0; i < frames; ++i) {
po[0] = pi[0];
po[1] = 0;
pi += 2;
po += 2;
}
} else if (bytes_per_frame == 6) {
int i, j;
unsigned char *pi = line6pcm->prev_fbuf;
unsigned char *po = urb_out->transfer_buffer;
for (i = 0; i < frames; ++i) {
for (j = 0; j < bytes_per_frame / 2; ++j)
po[j] = pi[j];
for (; j < bytes_per_frame; ++j)
po[j] = 0;
pi += bytes_per_frame;
po += bytes_per_frame;
}
}
if (--line6pcm->impulse_count <= 0) {
((unsigned char *)(urb_out->transfer_buffer))[bytes_per_frame -
1] =
line6pcm->impulse_volume;
line6pcm->impulse_count = line6pcm->impulse_period;
}
}
/*
Add signal to buffer for software monitoring.
*/
static void add_monitor_signal(struct urb *urb_out, unsigned char *signal,
int volume, int bytes_per_frame)
{
if (volume == 0)
return; /* zero volume - no change */
if (bytes_per_frame == 4) {
short *pi, *po, *buf_end;
pi = (short *)signal;
po = (short *)urb_out->transfer_buffer;
buf_end = po + urb_out->transfer_buffer_length / sizeof(*po);
for (; po < buf_end; ++pi, ++po)
*po += (*pi * volume) >> 8;
}
/*
We don't need to handle devices with 6 bytes per frame here
since they all support hardware monitoring.
*/
}
/*
Find a free URB, prepare audio data, and submit URB.
*/
static int submit_audio_out_urb(struct snd_line6_pcm *line6pcm)
{
int index;
unsigned long flags;
int i, urb_size, urb_frames;
int ret;
const int bytes_per_frame = line6pcm->properties->bytes_per_frame;
const int frame_increment =
line6pcm->properties->snd_line6_rates.rats[0].num_min;
const int frame_factor =
line6pcm->properties->snd_line6_rates.rats[0].den *
(USB_INTERVALS_PER_SECOND / LINE6_ISO_INTERVAL);
struct urb *urb_out;
spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
index =
find_first_zero_bit(&line6pcm->active_urb_out, LINE6_ISO_BUFFERS);
if (index < 0 || index >= LINE6_ISO_BUFFERS) {
spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
dev_err(line6pcm->line6->ifcdev, "no free URB found\n");
return -EINVAL;
}
urb_out = line6pcm->urb_audio_out[index];
urb_size = 0;
for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
/* compute frame size for given sampling rate */
int fsize = 0;
struct usb_iso_packet_descriptor *fout =
&urb_out->iso_frame_desc[i];
if (line6pcm->flags & LINE6_BITS_CAPTURE_STREAM)
fsize = line6pcm->prev_fsize;
if (fsize == 0) {
int n;
line6pcm->count_out += frame_increment;
n = line6pcm->count_out / frame_factor;
line6pcm->count_out -= n * frame_factor;
fsize = n * bytes_per_frame;
}
fout->offset = urb_size;
fout->length = fsize;
urb_size += fsize;
}
if (urb_size == 0) {
/* can't determine URB size */
spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
dev_err(line6pcm->line6->ifcdev, "driver bug: urb_size = 0\n");
return -EINVAL;
}
urb_frames = urb_size / bytes_per_frame;
urb_out->transfer_buffer =
line6pcm->buffer_out +
index * LINE6_ISO_PACKETS * line6pcm->max_packet_size;
urb_out->transfer_buffer_length = urb_size;
urb_out->context = line6pcm;
if (test_bit(LINE6_INDEX_PCM_ALSA_PLAYBACK_STREAM, &line6pcm->flags) &&
!test_bit(LINE6_INDEX_PAUSE_PLAYBACK, &line6pcm->flags)) {
struct snd_pcm_runtime *runtime =
get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK)->runtime;
if (line6pcm->pos_out + urb_frames > runtime->buffer_size) {
/*
The transferred area goes over buffer boundary,
copy the data to the temp buffer.
*/
int len;
len = runtime->buffer_size - line6pcm->pos_out;
if (len > 0) {
memcpy(urb_out->transfer_buffer,
runtime->dma_area +
line6pcm->pos_out * bytes_per_frame,
len * bytes_per_frame);
memcpy(urb_out->transfer_buffer +
len * bytes_per_frame, runtime->dma_area,
(urb_frames - len) * bytes_per_frame);
} else
dev_err(line6pcm->line6->ifcdev, "driver bug: len = %d\n",
len);
} else {
memcpy(urb_out->transfer_buffer,
runtime->dma_area +
line6pcm->pos_out * bytes_per_frame,
urb_out->transfer_buffer_length);
}
line6pcm->pos_out += urb_frames;
if (line6pcm->pos_out >= runtime->buffer_size)
line6pcm->pos_out -= runtime->buffer_size;
} else {
memset(urb_out->transfer_buffer, 0,
urb_out->transfer_buffer_length);
}
change_volume(urb_out, line6pcm->volume_playback, bytes_per_frame);
if (line6pcm->prev_fbuf != NULL) {
if (line6pcm->flags & LINE6_BITS_PCM_IMPULSE) {
create_impulse_test_signal(line6pcm, urb_out,
bytes_per_frame);
if (line6pcm->flags &
LINE6_BIT_PCM_ALSA_CAPTURE_STREAM) {
line6_capture_copy(line6pcm,
urb_out->transfer_buffer,
urb_out->
transfer_buffer_length);
line6_capture_check_period(line6pcm,
urb_out->transfer_buffer_length);
}
} else {
if (!
(line6pcm->line6->
properties->capabilities & LINE6_CAP_HWMON)
&& (line6pcm->flags & LINE6_BITS_PLAYBACK_STREAM)
&& (line6pcm->flags & LINE6_BITS_CAPTURE_STREAM))
add_monitor_signal(urb_out, line6pcm->prev_fbuf,
line6pcm->volume_monitor,
bytes_per_frame);
}
}
ret = usb_submit_urb(urb_out, GFP_ATOMIC);
if (ret == 0)
set_bit(index, &line6pcm->active_urb_out);
else
dev_err(line6pcm->line6->ifcdev,
"URB out #%d submission failed (%d)\n", index, ret);
spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
return 0;
}
/*
Submit all currently available playback URBs.
*/
int line6_submit_audio_out_all_urbs(struct snd_line6_pcm *line6pcm)
{
int ret, i;
for (i = 0; i < LINE6_ISO_BUFFERS; ++i) {
ret = submit_audio_out_urb(line6pcm);
if (ret < 0)
return ret;
}
return 0;
}
/*
Unlink all currently active playback URBs.
*/
void line6_unlink_audio_out_urbs(struct snd_line6_pcm *line6pcm)
{
unsigned int i;
for (i = LINE6_ISO_BUFFERS; i--;) {
if (test_bit(i, &line6pcm->active_urb_out)) {
if (!test_and_set_bit(i, &line6pcm->unlink_urb_out)) {
struct urb *u = line6pcm->urb_audio_out[i];
usb_unlink_urb(u);
}
}
}
}
/*
Wait until unlinking of all currently active playback URBs has been
finished.
*/
void line6_wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
{
int timeout = HZ;
unsigned int i;
int alive;
do {
alive = 0;
for (i = LINE6_ISO_BUFFERS; i--;) {
if (test_bit(i, &line6pcm->active_urb_out))
alive++;
}
if (!alive)
break;
set_current_state(TASK_UNINTERRUPTIBLE);
schedule_timeout(1);
} while (--timeout > 0);
if (alive)
snd_printk(KERN_ERR "timeout: still %d active urbs..\n", alive);
}
/*
Unlink all currently active playback URBs, and wait for finishing.
*/
void line6_unlink_wait_clear_audio_out_urbs(struct snd_line6_pcm *line6pcm)
{
line6_unlink_audio_out_urbs(line6pcm);
line6_wait_clear_audio_out_urbs(line6pcm);
}
void line6_free_playback_buffer(struct snd_line6_pcm *line6pcm)
{
kfree(line6pcm->buffer_out);
line6pcm->buffer_out = NULL;
}
/*
Callback for completed playback URB.
*/
static void audio_out_callback(struct urb *urb)
{
int i, index, length = 0, shutdown = 0;
unsigned long flags;
struct snd_line6_pcm *line6pcm = (struct snd_line6_pcm *)urb->context;
struct snd_pcm_substream *substream =
get_substream(line6pcm, SNDRV_PCM_STREAM_PLAYBACK);
#if USE_CLEAR_BUFFER_WORKAROUND
memset(urb->transfer_buffer, 0, urb->transfer_buffer_length);
#endif
line6pcm->last_frame_out = urb->start_frame;
/* find index of URB */
for (index = LINE6_ISO_BUFFERS; index--;)
if (urb == line6pcm->urb_audio_out[index])
break;
if (index < 0)
return; /* URB has been unlinked asynchronously */
for (i = LINE6_ISO_PACKETS; i--;)
length += urb->iso_frame_desc[i].length;
spin_lock_irqsave(&line6pcm->lock_audio_out, flags);
if (test_bit(LINE6_INDEX_PCM_ALSA_PLAYBACK_STREAM, &line6pcm->flags)) {
struct snd_pcm_runtime *runtime = substream->runtime;
line6pcm->pos_out_done +=
length / line6pcm->properties->bytes_per_frame;
if (line6pcm->pos_out_done >= runtime->buffer_size)
line6pcm->pos_out_done -= runtime->buffer_size;
}
clear_bit(index, &line6pcm->active_urb_out);
for (i = LINE6_ISO_PACKETS; i--;)
if (urb->iso_frame_desc[i].status == -EXDEV) {
shutdown = 1;
break;
}
if (test_and_clear_bit(index, &line6pcm->unlink_urb_out))
shutdown = 1;
spin_unlock_irqrestore(&line6pcm->lock_audio_out, flags);
if (!shutdown) {
submit_audio_out_urb(line6pcm);
if (test_bit(LINE6_INDEX_PCM_ALSA_PLAYBACK_STREAM,
&line6pcm->flags)) {
line6pcm->bytes_out += length;
if (line6pcm->bytes_out >= line6pcm->period_out) {
line6pcm->bytes_out %= line6pcm->period_out;
snd_pcm_period_elapsed(substream);
}
}
}
}
/* open playback callback */
static int snd_line6_playback_open(struct snd_pcm_substream *substream)
{
int err;
struct snd_pcm_runtime *runtime = substream->runtime;
struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
err = snd_pcm_hw_constraint_ratdens(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
(&line6pcm->
properties->snd_line6_rates));
if (err < 0)
return err;
runtime->hw = line6pcm->properties->snd_line6_playback_hw;
return 0;
}
/* close playback callback */
static int snd_line6_playback_close(struct snd_pcm_substream *substream)
{
return 0;
}
/* hw_params playback callback */
static int snd_line6_playback_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *hw_params)
{
int ret;
struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
/* -- Florian Demski [FD] */
/* don't ask me why, but this fixes the bug on my machine */
if (line6pcm == NULL) {
if (substream->pcm == NULL)
return -ENOMEM;
if (substream->pcm->private_data == NULL)
return -ENOMEM;
substream->private_data = substream->pcm->private_data;
line6pcm = snd_pcm_substream_chip(substream);
}
/* -- [FD] end */
ret = line6_pcm_acquire(line6pcm, LINE6_BIT_PCM_ALSA_PLAYBACK_BUFFER);
if (ret < 0)
return ret;
ret = snd_pcm_lib_malloc_pages(substream,
params_buffer_bytes(hw_params));
if (ret < 0) {
line6_pcm_release(line6pcm, LINE6_BIT_PCM_ALSA_PLAYBACK_BUFFER);
return ret;
}
line6pcm->period_out = params_period_bytes(hw_params);
return 0;
}
/* hw_free playback callback */
static int snd_line6_playback_hw_free(struct snd_pcm_substream *substream)
{
struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
line6_pcm_release(line6pcm, LINE6_BIT_PCM_ALSA_PLAYBACK_BUFFER);
return snd_pcm_lib_free_pages(substream);
}
/* trigger playback callback */
int snd_line6_playback_trigger(struct snd_line6_pcm *line6pcm, int cmd)
{
int err;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
err = line6_pcm_acquire(line6pcm,
LINE6_BIT_PCM_ALSA_PLAYBACK_STREAM);
if (err < 0)
return err;
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
err = line6_pcm_release(line6pcm,
LINE6_BIT_PCM_ALSA_PLAYBACK_STREAM);
if (err < 0)
return err;
break;
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
set_bit(LINE6_INDEX_PAUSE_PLAYBACK, &line6pcm->flags);
break;
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
clear_bit(LINE6_INDEX_PAUSE_PLAYBACK, &line6pcm->flags);
break;
default:
return -EINVAL;
}
return 0;
}
/* playback pointer callback */
static snd_pcm_uframes_t
snd_line6_playback_pointer(struct snd_pcm_substream *substream)
{
struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
return line6pcm->pos_out_done;
}
/* playback operators */
struct snd_pcm_ops snd_line6_playback_ops = {
.open = snd_line6_playback_open,
.close = snd_line6_playback_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = snd_line6_playback_hw_params,
.hw_free = snd_line6_playback_hw_free,
.prepare = snd_line6_prepare,
.trigger = snd_line6_trigger,
.pointer = snd_line6_playback_pointer,
};
int line6_create_audio_out_urbs(struct snd_line6_pcm *line6pcm)
{
struct usb_line6 *line6 = line6pcm->line6;
int i;
/* create audio URBs and fill in constant values: */
for (i = 0; i < LINE6_ISO_BUFFERS; ++i) {
struct urb *urb;
/* URB for audio out: */
urb = line6pcm->urb_audio_out[i] =
usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
if (urb == NULL)
return -ENOMEM;
urb->dev = line6->usbdev;
urb->pipe =
usb_sndisocpipe(line6->usbdev,
line6->properties->ep_audio_w &
USB_ENDPOINT_NUMBER_MASK);
urb->transfer_flags = URB_ISO_ASAP;
urb->start_frame = -1;
urb->number_of_packets = LINE6_ISO_PACKETS;
urb->interval = LINE6_ISO_INTERVAL;
urb->error_count = 0;
urb->complete = audio_out_callback;
}
return 0;
}
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