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authorDaniel Mack <daniel@caiaq.de>2010-03-11 21:13:25 +0100
committerTakashi Iwai <tiwai@suse.de>2010-03-12 12:21:26 +0100
commit23caaf19b11eda7054348452e1618d4512a86907 (patch)
treede0f69f74931fb033f3291c27691a3c2ac6367a2 /sound/usb/mixer.c
parent99fc86450c439039d2ef88d06b222fd51a779176 (diff)
downloadlinux-23caaf19b11eda7054348452e1618d4512a86907.tar.bz2
ALSA: usb-mixer: Add support for Audio Class v2.0
USB Audio Class v2.0 compliant devices have different descriptors and a different way of setting/getting min/max/res/cur properties. This patch adds support for them. Signed-off-by: Daniel Mack <daniel@caiaq.de> Cc: Clemens Ladisch <clemens@ladisch.de> Signed-off-by: Takashi Iwai <tiwai@suse.de>
Diffstat (limited to 'sound/usb/mixer.c')
-rw-r--r--sound/usb/mixer.c322
1 files changed, 242 insertions, 80 deletions
diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 994b0385235c..1deef623c081 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -33,6 +33,7 @@
#include <linux/string.h>
#include <linux/usb.h>
#include <linux/usb/audio.h>
+#include <linux/usb/audio-v2.h>
#include <sound/core.h>
#include <sound/control.h>
@@ -197,6 +198,7 @@ static int check_mapped_selector_name(struct mixer_build *state, int unitid,
/*
* find an audio control unit with the given unit id
+ * this doesn't return any clock related units, so they need to be handled elsewhere
*/
static void *find_audio_control_unit(struct mixer_build *state, unsigned char unit)
{
@@ -205,7 +207,7 @@ static void *find_audio_control_unit(struct mixer_build *state, unsigned char un
p = NULL;
while ((p = snd_usb_find_desc(state->buffer, state->buflen, p,
USB_DT_CS_INTERFACE)) != NULL) {
- if (p[0] >= 4 && p[2] >= UAC_INPUT_TERMINAL && p[2] <= UAC_EXTENSION_UNIT_V1 && p[3] == unit)
+ if (p[0] >= 4 && p[2] >= UAC_INPUT_TERMINAL && p[2] <= UAC2_EXTENSION_UNIT_V2 && p[3] == unit)
return p;
}
return NULL;
@@ -302,7 +304,7 @@ static int get_abs_value(struct usb_mixer_elem_info *cval, int val)
* retrieve a mixer value
*/
-static int get_ctl_value(struct usb_mixer_elem_info *cval, int request, int validx, int *value_ret)
+static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request, int validx, int *value_ret)
{
unsigned char buf[2];
int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
@@ -324,6 +326,58 @@ static int get_ctl_value(struct usb_mixer_elem_info *cval, int request, int vali
return -EINVAL;
}
+static int get_ctl_value_v2(struct usb_mixer_elem_info *cval, int request, int validx, int *value_ret)
+{
+ unsigned char buf[14]; /* enough space for one range of 4 bytes */
+ unsigned char *val;
+ int ret;
+ __u8 bRequest;
+
+ bRequest = (request == UAC_GET_CUR) ?
+ UAC2_CS_CUR : UAC2_CS_RANGE;
+
+ ret = snd_usb_ctl_msg(cval->mixer->chip->dev,
+ usb_rcvctrlpipe(cval->mixer->chip->dev, 0),
+ bRequest,
+ USB_RECIP_INTERFACE | USB_TYPE_CLASS | USB_DIR_IN,
+ validx, cval->mixer->ctrlif | (cval->id << 8),
+ buf, sizeof(buf), 1000);
+
+ if (ret < 0) {
+ snd_printdd(KERN_ERR "cannot get ctl value: req = %#x, wValue = %#x, wIndex = %#x, type = %d\n",
+ request, validx, cval->mixer->ctrlif | (cval->id << 8), cval->val_type);
+ return ret;
+ }
+
+ switch (request) {
+ case UAC_GET_CUR:
+ val = buf;
+ break;
+ case UAC_GET_MIN:
+ val = buf + sizeof(__u16);
+ break;
+ case UAC_GET_MAX:
+ val = buf + sizeof(__u16) * 2;
+ break;
+ case UAC_GET_RES:
+ val = buf + sizeof(__u16) * 3;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ *value_ret = convert_signed_value(cval, snd_usb_combine_bytes(val, sizeof(__u16)));
+
+ return 0;
+}
+
+static int get_ctl_value(struct usb_mixer_elem_info *cval, int request, int validx, int *value_ret)
+{
+ return (cval->mixer->protocol == UAC_VERSION_1) ?
+ get_ctl_value_v1(cval, request, validx, value_ret) :
+ get_ctl_value_v2(cval, request, validx, value_ret);
+}
+
static int get_cur_ctl_value(struct usb_mixer_elem_info *cval, int validx, int *value)
{
return get_ctl_value(cval, UAC_GET_CUR, validx, value);
@@ -348,8 +402,7 @@ static int get_cur_mix_value(struct usb_mixer_elem_info *cval,
err = get_cur_mix_raw(cval, channel, value);
if (err < 0) {
if (!cval->mixer->ignore_ctl_error)
- snd_printd(KERN_ERR "cannot get current value for "
- "control %d ch %d: err = %d\n",
+ snd_printd(KERN_ERR "cannot get current value for control %d ch %d: err = %d\n",
cval->control, channel, err);
return err;
}
@@ -367,8 +420,22 @@ int snd_usb_mixer_set_ctl_value(struct usb_mixer_elem_info *cval,
int request, int validx, int value_set)
{
unsigned char buf[2];
- int val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
- int timeout = 10;
+ int val_len, timeout = 10;
+
+ if (cval->mixer->protocol == UAC_VERSION_1) {
+ val_len = cval->val_type >= USB_MIXER_S16 ? 2 : 1;
+ } else { /* UAC_VERSION_2 */
+ /* audio class v2 controls are always 2 bytes in size */
+ val_len = sizeof(__u16);
+
+ /* FIXME */
+ if (request != UAC_SET_CUR) {
+ snd_printdd(KERN_WARNING "RANGE setting not yet supported\n");
+ return -EINVAL;
+ }
+
+ request = UAC2_CS_CUR;
+ }
value_set = convert_bytes_value(cval, value_set);
buf[0] = value_set & 0xff;
@@ -564,46 +631,65 @@ static int get_term_name(struct mixer_build *state, struct usb_audio_term *iterm
*/
static int check_input_term(struct mixer_build *state, int id, struct usb_audio_term *term)
{
- unsigned char *p1;
+ void *p1;
memset(term, 0, sizeof(*term));
while ((p1 = find_audio_control_unit(state, id)) != NULL) {
+ unsigned char *hdr = p1;
term->id = id;
- switch (p1[2]) {
+ switch (hdr[2]) {
case UAC_INPUT_TERMINAL:
- term->type = combine_word(p1 + 4);
- term->channels = p1[7];
- term->chconfig = combine_word(p1 + 8);
- term->name = p1[11];
+ if (state->mixer->protocol == UAC_VERSION_1) {
+ struct uac_input_terminal_descriptor *d = p1;
+ term->type = le16_to_cpu(d->wTerminalType);
+ term->channels = d->bNrChannels;
+ term->chconfig = le16_to_cpu(d->wChannelConfig);
+ term->name = d->iTerminal;
+ } else { /* UAC_VERSION_2 */
+ struct uac2_input_terminal_descriptor *d = p1;
+ term->type = le16_to_cpu(d->wTerminalType);
+ term->channels = d->bNrChannels;
+ term->chconfig = le32_to_cpu(d->bmChannelConfig);
+ term->name = d->iTerminal;
+ }
return 0;
- case UAC_FEATURE_UNIT:
- id = p1[4];
+ case UAC_FEATURE_UNIT: {
+ /* the header is the same for v1 and v2 */
+ struct uac_feature_unit_descriptor *d = p1;
+ id = d->bUnitID;
break; /* continue to parse */
- case UAC_MIXER_UNIT:
- term->type = p1[2] << 16; /* virtual type */
- term->channels = p1[5 + p1[4]];
- term->chconfig = combine_word(p1 + 6 + p1[4]);
- term->name = p1[p1[0] - 1];
+ }
+ case UAC_MIXER_UNIT: {
+ struct uac_mixer_unit_descriptor *d = p1;
+ term->type = d->bDescriptorSubtype << 16; /* virtual type */
+ term->channels = uac_mixer_unit_bNrChannels(d);
+ term->chconfig = uac_mixer_unit_wChannelConfig(d, state->mixer->protocol);
+ term->name = uac_mixer_unit_iMixer(d);
return 0;
- case UAC_SELECTOR_UNIT:
+ }
+ case UAC_SELECTOR_UNIT: {
+ struct uac_selector_unit_descriptor *d = p1;
/* call recursively to retrieve the channel info */
- if (check_input_term(state, p1[5], term) < 0)
+ if (check_input_term(state, d->baSourceID[0], term) < 0)
return -ENODEV;
- term->type = p1[2] << 16; /* virtual type */
+ term->type = d->bDescriptorSubtype << 16; /* virtual type */
term->id = id;
- term->name = p1[9 + p1[0] - 1];
+ term->name = uac_selector_unit_iSelector(d);
return 0;
+ }
case UAC_PROCESSING_UNIT_V1:
- case UAC_EXTENSION_UNIT_V1:
- if (p1[6] == 1) {
- id = p1[7];
+ case UAC_EXTENSION_UNIT_V1: {
+ struct uac_processing_unit_descriptor *d = p1;
+ if (d->bNrInPins) {
+ id = d->baSourceID[0];
break; /* continue to parse */
}
- term->type = p1[2] << 16; /* virtual type */
- term->channels = p1[7 + p1[6]];
- term->chconfig = combine_word(p1 + 8 + p1[6]);
- term->name = p1[12 + p1[6] + p1[11 + p1[6]]];
+ term->type = d->bDescriptorSubtype << 16; /* virtual type */
+ term->channels = uac_processing_unit_bNrChannels(d);
+ term->chconfig = uac_processing_unit_wChannelConfig(d, state->mixer->protocol);
+ term->name = uac_processing_unit_iProcessing(d, state->mixer->protocol);
return 0;
+ }
default:
return -ENODEV;
}
@@ -850,6 +936,15 @@ static struct snd_kcontrol_new usb_feature_unit_ctl = {
.put = mixer_ctl_feature_put,
};
+/* the read-only variant */
+static struct snd_kcontrol_new usb_feature_unit_ctl_ro = {
+ .iface = SNDRV_CTL_ELEM_IFACE_MIXER,
+ .name = "", /* will be filled later manually */
+ .info = mixer_ctl_feature_info,
+ .get = mixer_ctl_feature_get,
+ .put = NULL,
+};
+
/*
* build a feature control
@@ -862,7 +957,8 @@ static size_t append_ctl_name(struct snd_kcontrol *kctl, const char *str)
static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
unsigned int ctl_mask, int control,
- struct usb_audio_term *iterm, int unitid)
+ struct usb_audio_term *iterm, int unitid,
+ int read_only)
{
struct uac_feature_unit_descriptor *desc = raw_desc;
unsigned int len = 0;
@@ -906,7 +1002,11 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
/* get min/max values */
get_min_max(cval, 0);
- kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
+ if (read_only)
+ kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
+ else
+ kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
+
if (! kctl) {
snd_printk(KERN_ERR "cannot malloc kcontrol\n");
kfree(cval);
@@ -1016,24 +1116,34 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid, void
struct usb_audio_term iterm;
unsigned int master_bits, first_ch_bits;
int err, csize;
- struct uac_feature_unit_descriptor *ftr = _ftr;
+ struct uac_feature_unit_descriptor *hdr = _ftr;
+ __u8 *bmaControls;
+
+ if (state->mixer->protocol == UAC_VERSION_1) {
+ csize = hdr->bControlSize;
+ channels = (hdr->bLength - 7) / csize - 1;
+ bmaControls = hdr->bmaControls;
+ } else {
+ struct uac2_feature_unit_descriptor *ftr = _ftr;
+ csize = 4;
+ channels = (hdr->bLength - 6) / 4;
+ bmaControls = ftr->bmaControls;
+ }
- if (ftr->bLength < 7 || ! (csize = ftr->bControlSize) || ftr->bLength < 7 + csize) {
+ if (hdr->bLength < 7 || !csize || hdr->bLength < 7 + csize) {
snd_printk(KERN_ERR "usbaudio: unit %u: invalid UAC_FEATURE_UNIT descriptor\n", unitid);
return -EINVAL;
}
/* parse the source unit */
- if ((err = parse_audio_unit(state, ftr->bSourceID)) < 0)
+ if ((err = parse_audio_unit(state, hdr->bSourceID)) < 0)
return err;
/* determine the input source type and name */
- if (check_input_term(state, ftr->bSourceID, &iterm) < 0)
+ if (check_input_term(state, hdr->bSourceID, &iterm) < 0)
return -EINVAL;
- channels = (ftr->bLength - 7) / csize - 1;
-
- master_bits = snd_usb_combine_bytes(ftr->bmaControls, csize);
+ master_bits = snd_usb_combine_bytes(bmaControls, csize);
/* master configuration quirks */
switch (state->chip->usb_id) {
case USB_ID(0x08bb, 0x2702):
@@ -1044,21 +1154,54 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid, void
break;
}
if (channels > 0)
- first_ch_bits = snd_usb_combine_bytes(ftr->bmaControls + csize, csize);
+ first_ch_bits = snd_usb_combine_bytes(bmaControls + csize, csize);
else
first_ch_bits = 0;
- /* check all control types */
- for (i = 0; i < 10; i++) {
- unsigned int ch_bits = 0;
- for (j = 0; j < channels; j++) {
- unsigned int mask = snd_usb_combine_bytes(ftr->bmaControls + csize * (j+1), csize);
- if (mask & (1 << i))
- ch_bits |= (1 << j);
+
+ if (state->mixer->protocol == UAC_VERSION_1) {
+ /* check all control types */
+ for (i = 0; i < 10; i++) {
+ unsigned int ch_bits = 0;
+ for (j = 0; j < channels; j++) {
+ unsigned int mask = snd_usb_combine_bytes(bmaControls + csize * (j+1), csize);
+ if (mask & (1 << i))
+ ch_bits |= (1 << j);
+ }
+ /* audio class v1 controls are never read-only */
+ if (ch_bits & 1) /* the first channel must be set (for ease of programming) */
+ build_feature_ctl(state, _ftr, ch_bits, i, &iterm, unitid, 0);
+ if (master_bits & (1 << i))
+ build_feature_ctl(state, _ftr, 0, i, &iterm, unitid, 0);
+ }
+ } else { /* UAC_VERSION_2 */
+ for (i = 0; i < 30/2; i++) {
+ /* From the USB Audio spec v2.0:
+ bmaControls() is a (ch+1)-element array of 4-byte bitmaps,
+ each containing a set of bit pairs. If a Control is present,
+ it must be Host readable. If a certain Control is not
+ present then the bit pair must be set to 0b00.
+ If a Control is present but read-only, the bit pair must be
+ set to 0b01. If a Control is also Host programmable, the bit
+ pair must be set to 0b11. The value 0b10 is not allowed. */
+ unsigned int ch_bits = 0;
+ unsigned int ch_read_only = 0;
+
+ for (j = 0; j < channels; j++) {
+ unsigned int mask = snd_usb_combine_bytes(bmaControls + csize * (j+1), csize);
+ if (mask & (1 << (i * 2))) {
+ ch_bits |= (1 << j);
+ if (~mask & (1 << ((i * 2) + 1)))
+ ch_read_only |= (1 << j);
+ }
+ }
+
+ /* FIXME: the whole unit is read-only if any of the channels is marked read-only */
+ if (ch_bits & 1) /* the first channel must be set (for ease of programming) */
+ build_feature_ctl(state, _ftr, ch_bits, i, &iterm, unitid, !!ch_read_only);
+ if (master_bits & (1 << i * 2))
+ build_feature_ctl(state, _ftr, 0, i, &iterm, unitid,
+ ~master_bits & (1 << ((i * 2) + 1)));
}
- if (ch_bits & 1) /* the first channel must be set (for ease of programming) */
- build_feature_ctl(state, _ftr, ch_bits, i, &iterm, unitid);
- if (master_bits & (1 << i))
- build_feature_ctl(state, _ftr, 0, i, &iterm, unitid);
}
return 0;
@@ -1100,7 +1243,7 @@ static void build_mixer_unit_ctl(struct mixer_build *state,
cval->control = in_ch + 1; /* based on 1 */
cval->val_type = USB_MIXER_S16;
for (i = 0; i < num_outs; i++) {
- if (check_matrix_bitmap(uac_mixer_unit_bmControls(desc), in_ch, i, num_outs)) {
+ if (check_matrix_bitmap(uac_mixer_unit_bmControls(desc, state->mixer->protocol), in_ch, i, num_outs)) {
cval->cmask |= (1 << i);
cval->channels++;
}
@@ -1164,7 +1307,7 @@ static int parse_audio_mixer_unit(struct mixer_build *state, int unitid, void *r
int och, ich_has_controls = 0;
for (och = 0; och < num_outs; ++och) {
- if (check_matrix_bitmap(uac_mixer_unit_bmControls(desc),
+ if (check_matrix_bitmap(uac_mixer_unit_bmControls(desc, state->mixer->protocol),
ich, och, num_outs)) {
ich_has_controls = 1;
break;
@@ -1343,7 +1486,8 @@ static int build_audio_procunit(struct mixer_build *state, int unitid, void *raw
0, NULL, default_value_info
};
- if (desc->bLength < 13 || desc->bLength < 13 + num_ins || desc->bLength < num_ins + uac_processing_unit_bControlSize(desc)) {
+ if (desc->bLength < 13 || desc->bLength < 13 + num_ins ||
+ desc->bLength < num_ins + uac_processing_unit_bControlSize(desc, state->mixer->protocol)) {
snd_printk(KERN_ERR "invalid %s descriptor (id %d)\n", name, unitid);
return -EINVAL;
}
@@ -1361,7 +1505,7 @@ static int build_audio_procunit(struct mixer_build *state, int unitid, void *raw
info = &default_info;
for (valinfo = info->values; valinfo->control; valinfo++) {
- __u8 *controls = uac_processing_unit_bmControls(desc);
+ __u8 *controls = uac_processing_unit_bmControls(desc, state->mixer->protocol);
if (! (controls[valinfo->control / 8] & (1 << ((valinfo->control % 8) - 1))))
continue;
@@ -1381,7 +1525,7 @@ static int build_audio_procunit(struct mixer_build *state, int unitid, void *raw
/* get min/max values */
if (type == USB_PROC_UPDOWN && cval->control == USB_PROC_UPDOWN_MODE_SEL) {
- __u8 *control_spec = uac_processing_unit_specific(desc);
+ __u8 *control_spec = uac_processing_unit_specific(desc, state->mixer->protocol);
/* FIXME: hard-coded */
cval->min = 1;
cval->max = control_spec[0];
@@ -1414,7 +1558,7 @@ static int build_audio_procunit(struct mixer_build *state, int unitid, void *raw
else if (info->name)
strlcpy(kctl->id.name, info->name, sizeof(kctl->id.name));
else {
- nameid = uac_processing_unit_iProcessing(desc);
+ nameid = uac_processing_unit_iProcessing(desc, state->mixer->protocol);
len = 0;
if (nameid)
len = snd_usb_copy_string_desc(state, nameid, kctl->id.name, sizeof(kctl->id.name));
@@ -1676,9 +1820,17 @@ static int parse_audio_unit(struct mixer_build *state, int unitid)
case UAC_FEATURE_UNIT:
return parse_audio_feature_unit(state, unitid, p1);
case UAC_PROCESSING_UNIT_V1:
- return parse_audio_processing_unit(state, unitid, p1);
+ /* UAC2_EFFECT_UNIT has the same value */
+ if (state->mixer->protocol == UAC_VERSION_1)
+ return parse_audio_processing_unit(state, unitid, p1);
+ else
+ return 0; /* FIXME - effect units not implemented yet */
case UAC_EXTENSION_UNIT_V1:
- return parse_audio_extension_unit(state, unitid, p1);
+ /* UAC2_PROCESSING_UNIT_V2 has the same value */
+ if (state->mixer->protocol == UAC_VERSION_1)
+ return parse_audio_extension_unit(state, unitid, p1);
+ else /* UAC_VERSION_2 */
+ return parse_audio_processing_unit(state, unitid, p1);
default:
snd_printk(KERN_ERR "usbaudio: unit %u: unexpected type 0x%02x\n", unitid, p1[2]);
return -EINVAL;
@@ -1711,11 +1863,11 @@ static int snd_usb_mixer_dev_free(struct snd_device *device)
*/
static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
{
- struct uac_output_terminal_descriptor_v1 *desc;
struct mixer_build state;
int err;
const struct usbmix_ctl_map *map;
struct usb_host_interface *hostif;
+ void *p;
hostif = &usb_ifnum_to_if(mixer->chip->dev, mixer->ctrlif)->altsetting[0];
memset(&state, 0, sizeof(state));
@@ -1734,18 +1886,35 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
}
}
- desc = NULL;
- while ((desc = snd_usb_find_csint_desc(hostif->extra, hostif->extralen, desc, UAC_OUTPUT_TERMINAL)) != NULL) {
- if (desc->bLength < 9)
- continue; /* invalid descriptor? */
- set_bit(desc->bTerminalID, state.unitbitmap); /* mark terminal ID as visited */
- state.oterm.id = desc->bTerminalID;
- state.oterm.type = le16_to_cpu(desc->wTerminalType);
- state.oterm.name = desc->iTerminal;
- err = parse_audio_unit(&state, desc->bSourceID);
- if (err < 0)
- return err;
+ p = NULL;
+ while ((p = snd_usb_find_csint_desc(hostif->extra, hostif->extralen, p, UAC_OUTPUT_TERMINAL)) != NULL) {
+ if (mixer->protocol == UAC_VERSION_1) {
+ struct uac_output_terminal_descriptor_v1 *desc = p;
+
+ if (desc->bLength < sizeof(*desc))
+ continue; /* invalid descriptor? */
+ set_bit(desc->bTerminalID, state.unitbitmap); /* mark terminal ID as visited */
+ state.oterm.id = desc->bTerminalID;
+ state.oterm.type = le16_to_cpu(desc->wTerminalType);
+ state.oterm.name = desc->iTerminal;
+ err = parse_audio_unit(&state, desc->bSourceID);
+ if (err < 0)
+ return err;
+ } else { /* UAC_VERSION_2 */
+ struct uac2_output_terminal_descriptor *desc = p;
+
+ if (desc->bLength < sizeof(*desc))
+ continue; /* invalid descriptor? */
+ set_bit(desc->bTerminalID, state.unitbitmap); /* mark terminal ID as visited */
+ state.oterm.id = desc->bTerminalID;
+ state.oterm.type = le16_to_cpu(desc->wTerminalType);
+ state.oterm.name = desc->iTerminal;
+ err = parse_audio_unit(&state, desc->bSourceID);
+ if (err < 0)
+ return err;
+ }
}
+
return 0;
}
@@ -1868,7 +2037,7 @@ int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
struct usb_mixer_interface *mixer;
struct snd_info_entry *entry;
struct usb_host_interface *host_iface;
- int err, protocol;
+ int err;
strcpy(chip->card->mixername, "USB Mixer");
@@ -1886,14 +2055,7 @@ int snd_usb_create_mixer(struct snd_usb_audio *chip, int ctrlif,
}
host_iface = &usb_ifnum_to_if(chip->dev, ctrlif)->altsetting[0];
- protocol = host_iface->desc.bInterfaceProtocol;
-
- /* FIXME! */
- if (protocol != UAC_VERSION_1) {
- snd_printk(KERN_WARNING "mixer interface protocol 0x%02x not yet supported\n",
- protocol);
- return 0;
- }
+ mixer->protocol = host_iface->desc.bInterfaceProtocol;
if ((err = snd_usb_mixer_controls(mixer)) < 0 ||
(err = snd_usb_mixer_status_create(mixer)) < 0)