linux/sound/usb/line6/capture.c
Bhumika Goyal e195a331c4 ALSA: line6: make snd_pcm_ops const
Make these const as they are only passed to a const argument of the
function snd_pcm_set_ops in the file referencing them. Also, add const
to the declaration in the headers.

Structures found using Coccinelle and changes done by hand.

Signed-off-by: Bhumika Goyal <bhumirks@gmail.com>
Reviewed-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-10-02 14:33:23 +02:00

298 lines
7.5 KiB
C

/*
* Line 6 Linux USB driver
*
* 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 "capture.h"
#include "driver.h"
#include "pcm.h"
/*
Find a free URB and submit it.
must be called in line6pcm->in.lock context
*/
static int submit_audio_in_urb(struct snd_line6_pcm *line6pcm)
{
int index;
int i, urb_size;
int ret;
struct urb *urb_in;
index = find_first_zero_bit(&line6pcm->in.active_urbs,
line6pcm->line6->iso_buffers);
if (index < 0 || index >= line6pcm->line6->iso_buffers) {
dev_err(line6pcm->line6->ifcdev, "no free URB found\n");
return -EINVAL;
}
urb_in = line6pcm->in.urbs[index];
urb_size = 0;
for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
struct usb_iso_packet_descriptor *fin =
&urb_in->iso_frame_desc[i];
fin->offset = urb_size;
fin->length = line6pcm->max_packet_size_in;
urb_size += line6pcm->max_packet_size_in;
}
urb_in->transfer_buffer =
line6pcm->in.buffer +
index * LINE6_ISO_PACKETS * line6pcm->max_packet_size_in;
urb_in->transfer_buffer_length = urb_size;
urb_in->context = line6pcm;
ret = usb_submit_urb(urb_in, GFP_ATOMIC);
if (ret == 0)
set_bit(index, &line6pcm->in.active_urbs);
else
dev_err(line6pcm->line6->ifcdev,
"URB in #%d submission failed (%d)\n", index, ret);
return 0;
}
/*
Submit all currently available capture URBs.
must be called in line6pcm->in.lock context
*/
int line6_submit_audio_in_all_urbs(struct snd_line6_pcm *line6pcm)
{
int ret = 0, i;
for (i = 0; i < line6pcm->line6->iso_buffers; ++i) {
ret = submit_audio_in_urb(line6pcm);
if (ret < 0)
break;
}
return ret;
}
/*
Copy data into ALSA capture buffer.
*/
void line6_capture_copy(struct snd_line6_pcm *line6pcm, char *fbuf, int fsize)
{
struct snd_pcm_substream *substream =
get_substream(line6pcm, SNDRV_PCM_STREAM_CAPTURE);
struct snd_pcm_runtime *runtime = substream->runtime;
const int bytes_per_frame =
line6pcm->properties->bytes_per_channel *
line6pcm->properties->capture_hw.channels_max;
int frames = fsize / bytes_per_frame;
if (runtime == NULL)
return;
if (line6pcm->in.pos_done + frames > runtime->buffer_size) {
/*
The transferred area goes over buffer boundary,
copy two separate chunks.
*/
int len;
len = runtime->buffer_size - line6pcm->in.pos_done;
if (len > 0) {
memcpy(runtime->dma_area +
line6pcm->in.pos_done * bytes_per_frame, fbuf,
len * bytes_per_frame);
memcpy(runtime->dma_area, fbuf + len * bytes_per_frame,
(frames - len) * bytes_per_frame);
} else {
/* this is somewhat paranoid */
dev_err(line6pcm->line6->ifcdev,
"driver bug: len = %d\n", len);
}
} else {
/* copy single chunk */
memcpy(runtime->dma_area +
line6pcm->in.pos_done * bytes_per_frame, fbuf, fsize);
}
line6pcm->in.pos_done += frames;
if (line6pcm->in.pos_done >= runtime->buffer_size)
line6pcm->in.pos_done -= runtime->buffer_size;
}
void line6_capture_check_period(struct snd_line6_pcm *line6pcm, int length)
{
struct snd_pcm_substream *substream =
get_substream(line6pcm, SNDRV_PCM_STREAM_CAPTURE);
line6pcm->in.bytes += length;
if (line6pcm->in.bytes >= line6pcm->in.period) {
line6pcm->in.bytes %= line6pcm->in.period;
spin_unlock(&line6pcm->in.lock);
snd_pcm_period_elapsed(substream);
spin_lock(&line6pcm->in.lock);
}
}
/*
* Callback for completed capture URB.
*/
static void audio_in_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;
line6pcm->in.last_frame = urb->start_frame;
/* find index of URB */
for (index = 0; index < line6pcm->line6->iso_buffers; ++index)
if (urb == line6pcm->in.urbs[index])
break;
spin_lock_irqsave(&line6pcm->in.lock, flags);
for (i = 0; i < LINE6_ISO_PACKETS; ++i) {
char *fbuf;
int fsize;
struct usb_iso_packet_descriptor *fin = &urb->iso_frame_desc[i];
if (fin->status == -EXDEV) {
shutdown = 1;
break;
}
fbuf = urb->transfer_buffer + fin->offset;
fsize = fin->actual_length;
if (fsize > line6pcm->max_packet_size_in) {
dev_err(line6pcm->line6->ifcdev,
"driver and/or device bug: packet too large (%d > %d)\n",
fsize, line6pcm->max_packet_size_in);
}
length += fsize;
BUILD_BUG_ON_MSG(LINE6_ISO_PACKETS != 1,
"The following code assumes LINE6_ISO_PACKETS == 1");
/* TODO:
* Also, if iso_buffers != 2, the prev frame is almost random at
* playback side.
* This needs to be redesigned. It should be "stable", but we may
* experience sync problems on such high-speed configs.
*/
line6pcm->prev_fbuf = fbuf;
line6pcm->prev_fsize = fsize /
(line6pcm->properties->bytes_per_channel *
line6pcm->properties->capture_hw.channels_max);
if (!test_bit(LINE6_STREAM_IMPULSE, &line6pcm->in.running) &&
test_bit(LINE6_STREAM_PCM, &line6pcm->in.running) &&
fsize > 0)
line6_capture_copy(line6pcm, fbuf, fsize);
}
clear_bit(index, &line6pcm->in.active_urbs);
if (test_and_clear_bit(index, &line6pcm->in.unlink_urbs))
shutdown = 1;
if (!shutdown) {
submit_audio_in_urb(line6pcm);
if (!test_bit(LINE6_STREAM_IMPULSE, &line6pcm->in.running) &&
test_bit(LINE6_STREAM_PCM, &line6pcm->in.running))
line6_capture_check_period(line6pcm, length);
}
spin_unlock_irqrestore(&line6pcm->in.lock, flags);
}
/* open capture callback */
static int snd_line6_capture_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->rates);
if (err < 0)
return err;
line6_pcm_acquire(line6pcm, LINE6_STREAM_CAPTURE_HELPER, false);
runtime->hw = line6pcm->properties->capture_hw;
return 0;
}
/* close capture callback */
static int snd_line6_capture_close(struct snd_pcm_substream *substream)
{
struct snd_line6_pcm *line6pcm = snd_pcm_substream_chip(substream);
line6_pcm_release(line6pcm, LINE6_STREAM_CAPTURE_HELPER);
return 0;
}
/* capture operators */
const struct snd_pcm_ops snd_line6_capture_ops = {
.open = snd_line6_capture_open,
.close = snd_line6_capture_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = snd_line6_hw_params,
.hw_free = snd_line6_hw_free,
.prepare = snd_line6_prepare,
.trigger = snd_line6_trigger,
.pointer = snd_line6_pointer,
};
int line6_create_audio_in_urbs(struct snd_line6_pcm *line6pcm)
{
struct usb_line6 *line6 = line6pcm->line6;
int i;
line6pcm->in.urbs = kzalloc(
sizeof(struct urb *) * line6->iso_buffers, GFP_KERNEL);
if (line6pcm->in.urbs == NULL)
return -ENOMEM;
/* create audio URBs and fill in constant values: */
for (i = 0; i < line6->iso_buffers; ++i) {
struct urb *urb;
/* URB for audio in: */
urb = line6pcm->in.urbs[i] =
usb_alloc_urb(LINE6_ISO_PACKETS, GFP_KERNEL);
if (urb == NULL)
return -ENOMEM;
urb->dev = line6->usbdev;
urb->pipe =
usb_rcvisocpipe(line6->usbdev,
line6->properties->ep_audio_r &
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_in_callback;
}
return 0;
}