kernel-ark/sound/usb/format.c
Dan Carpenter 38d7b08f37 ALSA: sound/usb/format: silence uninitialized variable warnings
Gcc complains that ret might be used uninitialized:

sound/usb/format.c: In function ‘snd_usb_parse_audio_format’:
sound/usb/format.c:354: warning: ‘ret’ may be used uninitialized in this function
sound/usb/format.c:354: note: ‘ret’ was declared here
sound/usb/format.c:414: warning: ‘ret’ may be used uninitialized in this function
sound/usb/format.c:414: note: ‘ret’ was declared here

I suppose it could be uninitialized if there is ever a UAC_VERSION_3
released. Anyway this patch is worthwhile if only to silence the gcc
warning.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Acked-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2010-08-15 14:28:20 +02:00

508 lines
14 KiB
C

/*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
#include <linux/usb/audio-v2.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include "usbaudio.h"
#include "card.h"
#include "quirks.h"
#include "helper.h"
#include "debug.h"
#include "clock.h"
/*
* parse the audio format type I descriptor
* and returns the corresponding pcm format
*
* @dev: usb device
* @fp: audioformat record
* @format: the format tag (wFormatTag)
* @fmt: the format type descriptor
*/
static u64 parse_audio_format_i_type(struct snd_usb_audio *chip,
struct audioformat *fp,
int format, void *_fmt,
int protocol)
{
int sample_width, sample_bytes;
u64 pcm_formats;
switch (protocol) {
case UAC_VERSION_1: {
struct uac_format_type_i_discrete_descriptor *fmt = _fmt;
sample_width = fmt->bBitResolution;
sample_bytes = fmt->bSubframeSize;
format = 1 << format;
break;
}
case UAC_VERSION_2: {
struct uac_format_type_i_ext_descriptor *fmt = _fmt;
sample_width = fmt->bBitResolution;
sample_bytes = fmt->bSubslotSize;
format <<= 1;
break;
}
default:
return -EINVAL;
}
pcm_formats = 0;
if (format == 0 || format == (1 << UAC_FORMAT_TYPE_I_UNDEFINED)) {
/* some devices don't define this correctly... */
snd_printdd(KERN_INFO "%d:%u:%d : format type 0 is detected, processed as PCM\n",
chip->dev->devnum, fp->iface, fp->altsetting);
format = 1 << UAC_FORMAT_TYPE_I_PCM;
}
if (format & (1 << UAC_FORMAT_TYPE_I_PCM)) {
if (sample_width > sample_bytes * 8) {
snd_printk(KERN_INFO "%d:%u:%d : sample bitwidth %d in over sample bytes %d\n",
chip->dev->devnum, fp->iface, fp->altsetting,
sample_width, sample_bytes);
}
/* check the format byte size */
switch (sample_bytes) {
case 1:
pcm_formats |= SNDRV_PCM_FMTBIT_S8;
break;
case 2:
if (snd_usb_is_big_endian_format(chip, fp))
pcm_formats |= SNDRV_PCM_FMTBIT_S16_BE; /* grrr, big endian!! */
else
pcm_formats |= SNDRV_PCM_FMTBIT_S16_LE;
break;
case 3:
if (snd_usb_is_big_endian_format(chip, fp))
pcm_formats |= SNDRV_PCM_FMTBIT_S24_3BE; /* grrr, big endian!! */
else
pcm_formats |= SNDRV_PCM_FMTBIT_S24_3LE;
break;
case 4:
pcm_formats |= SNDRV_PCM_FMTBIT_S32_LE;
break;
default:
snd_printk(KERN_INFO "%d:%u:%d : unsupported sample bitwidth %d in %d bytes\n",
chip->dev->devnum, fp->iface, fp->altsetting,
sample_width, sample_bytes);
break;
}
}
if (format & (1 << UAC_FORMAT_TYPE_I_PCM8)) {
/* Dallas DS4201 workaround: it advertises U8 format, but really
supports S8. */
if (chip->usb_id == USB_ID(0x04fa, 0x4201))
pcm_formats |= SNDRV_PCM_FMTBIT_S8;
else
pcm_formats |= SNDRV_PCM_FMTBIT_U8;
}
if (format & (1 << UAC_FORMAT_TYPE_I_IEEE_FLOAT)) {
pcm_formats |= SNDRV_PCM_FMTBIT_FLOAT_LE;
}
if (format & (1 << UAC_FORMAT_TYPE_I_ALAW)) {
pcm_formats |= SNDRV_PCM_FMTBIT_A_LAW;
}
if (format & (1 << UAC_FORMAT_TYPE_I_MULAW)) {
pcm_formats |= SNDRV_PCM_FMTBIT_MU_LAW;
}
if (format & ~0x3f) {
snd_printk(KERN_INFO "%d:%u:%d : unsupported format bits %#x\n",
chip->dev->devnum, fp->iface, fp->altsetting, format);
}
return pcm_formats;
}
/*
* parse the format descriptor and stores the possible sample rates
* on the audioformat table (audio class v1).
*
* @dev: usb device
* @fp: audioformat record
* @fmt: the format descriptor
* @offset: the start offset of descriptor pointing the rate type
* (7 for type I and II, 8 for type II)
*/
static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audioformat *fp,
unsigned char *fmt, int offset)
{
int nr_rates = fmt[offset];
if (fmt[0] < offset + 1 + 3 * (nr_rates ? nr_rates : 2)) {
snd_printk(KERN_ERR "%d:%u:%d : invalid UAC_FORMAT_TYPE desc\n",
chip->dev->devnum, fp->iface, fp->altsetting);
return -1;
}
if (nr_rates) {
/*
* build the rate table and bitmap flags
*/
int r, idx;
fp->rate_table = kmalloc(sizeof(int) * nr_rates, GFP_KERNEL);
if (fp->rate_table == NULL) {
snd_printk(KERN_ERR "cannot malloc\n");
return -1;
}
fp->nr_rates = 0;
fp->rate_min = fp->rate_max = 0;
for (r = 0, idx = offset + 1; r < nr_rates; r++, idx += 3) {
unsigned int rate = combine_triple(&fmt[idx]);
if (!rate)
continue;
/* C-Media CM6501 mislabels its 96 kHz altsetting */
if (rate == 48000 && nr_rates == 1 &&
(chip->usb_id == USB_ID(0x0d8c, 0x0201) ||
chip->usb_id == USB_ID(0x0d8c, 0x0102)) &&
fp->altsetting == 5 && fp->maxpacksize == 392)
rate = 96000;
/* Creative VF0470 Live Cam reports 16 kHz instead of 8kHz */
if (rate == 16000 && chip->usb_id == USB_ID(0x041e, 0x4068))
rate = 8000;
fp->rate_table[fp->nr_rates] = rate;
if (!fp->rate_min || rate < fp->rate_min)
fp->rate_min = rate;
if (!fp->rate_max || rate > fp->rate_max)
fp->rate_max = rate;
fp->rates |= snd_pcm_rate_to_rate_bit(rate);
fp->nr_rates++;
}
if (!fp->nr_rates) {
hwc_debug("All rates were zero. Skipping format!\n");
return -1;
}
} else {
/* continuous rates */
fp->rates = SNDRV_PCM_RATE_CONTINUOUS;
fp->rate_min = combine_triple(&fmt[offset + 1]);
fp->rate_max = combine_triple(&fmt[offset + 4]);
}
return 0;
}
/*
* Helper function to walk the array of sample rate triplets reported by
* the device. The problem is that we need to parse whole array first to
* get to know how many sample rates we have to expect.
* Then fp->rate_table can be allocated and filled.
*/
static int parse_uac2_sample_rate_range(struct audioformat *fp, int nr_triplets,
const unsigned char *data)
{
int i, nr_rates = 0;
fp->rates = fp->rate_min = fp->rate_max = 0;
for (i = 0; i < nr_triplets; i++) {
int min = combine_quad(&data[2 + 12 * i]);
int max = combine_quad(&data[6 + 12 * i]);
int res = combine_quad(&data[10 + 12 * i]);
int rate;
if ((max < 0) || (min < 0) || (res < 0) || (max < min))
continue;
/*
* for ranges with res == 1, we announce a continuous sample
* rate range, and this function should return 0 for no further
* parsing.
*/
if (res == 1) {
fp->rate_min = min;
fp->rate_max = max;
fp->rates = SNDRV_PCM_RATE_CONTINUOUS;
return 0;
}
for (rate = min; rate <= max; rate += res) {
if (fp->rate_table)
fp->rate_table[nr_rates] = rate;
if (!fp->rate_min || rate < fp->rate_min)
fp->rate_min = rate;
if (!fp->rate_max || rate > fp->rate_max)
fp->rate_max = rate;
fp->rates |= snd_pcm_rate_to_rate_bit(rate);
nr_rates++;
/* avoid endless loop */
if (res == 0)
break;
}
}
return nr_rates;
}
/*
* parse the format descriptor and stores the possible sample rates
* on the audioformat table (audio class v2).
*/
static int parse_audio_format_rates_v2(struct snd_usb_audio *chip,
struct audioformat *fp)
{
struct usb_device *dev = chip->dev;
unsigned char tmp[2], *data;
int nr_triplets, data_size, ret = 0;
int clock = snd_usb_clock_find_source(chip, fp->clock);
if (clock < 0) {
snd_printk(KERN_ERR "%s(): unable to find clock source (clock %d)\n",
__func__, clock);
goto err;
}
/* get the number of sample rates first by only fetching 2 bytes */
ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_RANGE,
USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
UAC2_CS_CONTROL_SAM_FREQ << 8,
snd_usb_ctrl_intf(chip) | (clock << 8),
tmp, sizeof(tmp), 1000);
if (ret < 0) {
snd_printk(KERN_ERR "%s(): unable to retrieve number of sample rates (clock %d)\n",
__func__, clock);
goto err;
}
nr_triplets = (tmp[1] << 8) | tmp[0];
data_size = 2 + 12 * nr_triplets;
data = kzalloc(data_size, GFP_KERNEL);
if (!data) {
ret = -ENOMEM;
goto err;
}
/* now get the full information */
ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0), UAC2_CS_RANGE,
USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
UAC2_CS_CONTROL_SAM_FREQ << 8,
snd_usb_ctrl_intf(chip) | (clock << 8),
data, data_size, 1000);
if (ret < 0) {
snd_printk(KERN_ERR "%s(): unable to retrieve sample rate range (clock %d)\n",
__func__, clock);
ret = -EINVAL;
goto err_free;
}
/* Call the triplet parser, and make sure fp->rate_table is NULL.
* We just use the return value to know how many sample rates we
* will have to deal with. */
kfree(fp->rate_table);
fp->rate_table = NULL;
fp->nr_rates = parse_uac2_sample_rate_range(fp, nr_triplets, data);
if (fp->nr_rates == 0) {
/* SNDRV_PCM_RATE_CONTINUOUS */
ret = 0;
goto err_free;
}
fp->rate_table = kmalloc(sizeof(int) * fp->nr_rates, GFP_KERNEL);
if (!fp->rate_table) {
ret = -ENOMEM;
goto err_free;
}
/* Call the triplet parser again, but this time, fp->rate_table is
* allocated, so the rates will be stored */
parse_uac2_sample_rate_range(fp, nr_triplets, data);
err_free:
kfree(data);
err:
return ret;
}
/*
* parse the format type I and III descriptors
*/
static int parse_audio_format_i(struct snd_usb_audio *chip,
struct audioformat *fp, int format,
struct uac_format_type_i_continuous_descriptor *fmt,
struct usb_host_interface *iface)
{
struct usb_interface_descriptor *altsd = get_iface_desc(iface);
int protocol = altsd->bInterfaceProtocol;
int pcm_format, ret;
if (fmt->bFormatType == UAC_FORMAT_TYPE_III) {
/* FIXME: the format type is really IECxxx
* but we give normal PCM format to get the existing
* apps working...
*/
switch (chip->usb_id) {
case USB_ID(0x0763, 0x2003): /* M-Audio Audiophile USB */
if (chip->setup == 0x00 &&
fp->altsetting == 6)
pcm_format = SNDRV_PCM_FORMAT_S16_BE;
else
pcm_format = SNDRV_PCM_FORMAT_S16_LE;
break;
default:
pcm_format = SNDRV_PCM_FORMAT_S16_LE;
}
fp->formats = 1uLL << pcm_format;
} else {
fp->formats = parse_audio_format_i_type(chip, fp, format,
fmt, protocol);
if (!fp->formats)
return -1;
}
/* gather possible sample rates */
/* audio class v1 reports possible sample rates as part of the
* proprietary class specific descriptor.
* audio class v2 uses class specific EP0 range requests for that.
*/
switch (protocol) {
case UAC_VERSION_1:
fp->channels = fmt->bNrChannels;
ret = parse_audio_format_rates_v1(chip, fp, (unsigned char *) fmt, 7);
break;
case UAC_VERSION_2:
/* fp->channels is already set in this case */
ret = parse_audio_format_rates_v2(chip, fp);
break;
default:
snd_printk(KERN_ERR "%d:%u:%d : invalid protocol version %d\n",
chip->dev->devnum, fp->iface, fp->altsetting, protocol);
return -EINVAL;
}
if (fp->channels < 1) {
snd_printk(KERN_ERR "%d:%u:%d : invalid channels %d\n",
chip->dev->devnum, fp->iface, fp->altsetting, fp->channels);
return -1;
}
return ret;
}
/*
* parse the format type II descriptor
*/
static int parse_audio_format_ii(struct snd_usb_audio *chip,
struct audioformat *fp,
int format, void *_fmt,
struct usb_host_interface *iface)
{
int brate, framesize, ret;
struct usb_interface_descriptor *altsd = get_iface_desc(iface);
int protocol = altsd->bInterfaceProtocol;
switch (format) {
case UAC_FORMAT_TYPE_II_AC3:
/* FIXME: there is no AC3 format defined yet */
// fp->formats = SNDRV_PCM_FMTBIT_AC3;
fp->formats = SNDRV_PCM_FMTBIT_U8; /* temporary hack to receive byte streams */
break;
case UAC_FORMAT_TYPE_II_MPEG:
fp->formats = SNDRV_PCM_FMTBIT_MPEG;
break;
default:
snd_printd(KERN_INFO "%d:%u:%d : unknown format tag %#x is detected. processed as MPEG.\n",
chip->dev->devnum, fp->iface, fp->altsetting, format);
fp->formats = SNDRV_PCM_FMTBIT_MPEG;
break;
}
fp->channels = 1;
switch (protocol) {
case UAC_VERSION_1: {
struct uac_format_type_ii_discrete_descriptor *fmt = _fmt;
brate = le16_to_cpu(fmt->wMaxBitRate);
framesize = le16_to_cpu(fmt->wSamplesPerFrame);
snd_printd(KERN_INFO "found format II with max.bitrate = %d, frame size=%d\n", brate, framesize);
fp->frame_size = framesize;
ret = parse_audio_format_rates_v1(chip, fp, _fmt, 8); /* fmt[8..] sample rates */
break;
}
case UAC_VERSION_2: {
struct uac_format_type_ii_ext_descriptor *fmt = _fmt;
brate = le16_to_cpu(fmt->wMaxBitRate);
framesize = le16_to_cpu(fmt->wSamplesPerFrame);
snd_printd(KERN_INFO "found format II with max.bitrate = %d, frame size=%d\n", brate, framesize);
fp->frame_size = framesize;
ret = parse_audio_format_rates_v2(chip, fp);
break;
}
default:
snd_printk(KERN_ERR "%d:%u:%d : invalid protocol version %d\n",
chip->dev->devnum, fp->iface, fp->altsetting, protocol);
return -EINVAL;
}
return ret;
}
int snd_usb_parse_audio_format(struct snd_usb_audio *chip, struct audioformat *fp,
int format, struct uac_format_type_i_continuous_descriptor *fmt,
int stream, struct usb_host_interface *iface)
{
int err;
switch (fmt->bFormatType) {
case UAC_FORMAT_TYPE_I:
case UAC_FORMAT_TYPE_III:
err = parse_audio_format_i(chip, fp, format, fmt, iface);
break;
case UAC_FORMAT_TYPE_II:
err = parse_audio_format_ii(chip, fp, format, fmt, iface);
break;
default:
snd_printd(KERN_INFO "%d:%u:%d : format type %d is not supported yet\n",
chip->dev->devnum, fp->iface, fp->altsetting,
fmt->bFormatType);
return -ENOTSUPP;
}
fp->fmt_type = fmt->bFormatType;
if (err < 0)
return err;
#if 1
/* FIXME: temporary hack for extigy/audigy 2 nx/zs */
/* extigy apparently supports sample rates other than 48k
* but not in ordinary way. so we enable only 48k atm.
*/
if (chip->usb_id == USB_ID(0x041e, 0x3000) ||
chip->usb_id == USB_ID(0x041e, 0x3020) ||
chip->usb_id == USB_ID(0x041e, 0x3061)) {
if (fmt->bFormatType == UAC_FORMAT_TYPE_I &&
fp->rates != SNDRV_PCM_RATE_48000 &&
fp->rates != SNDRV_PCM_RATE_96000)
return -ENOTSUPP;
}
#endif
return 0;
}