ALSA: usb-audio: Add support for Presonus Studio 1810c

This patch adds support for Presonus Studio 1810c, a usb interface
that's UAC2 compliant with a few quirks and a few extra hw-specific
controls. I've tested all 3 altsettings and the added switch
controls and they work as expected.

More infos on the card:
https://www.presonus.com/products/Studio-1810c

Note that this work is based on packet inspection with
usbmon. I just wanted to get this card to work for using
it on our open-source radio station:
https://github.com/UoC-Radio

v2 address issues reported by Takashi:
* Properly get/set enum type controls
* Prevent race condition on switch_get/set
* Various control naming changes
* Various coding style fixes

v3 improve readability of sample rate filtering
and some other minor changes.

Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Link: https://lore.kernel.org/r/5e47481a.1c69fb81.befb3.8dac@mx.google.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Nick Kossifidis 2020-02-15 03:23:35 +02:00 committed by Takashi Iwai
parent 146f66975b
commit 8dc5efe3d1
6 changed files with 681 additions and 0 deletions

View File

@ -13,6 +13,7 @@ snd-usb-audio-objs := card.o \
mixer_scarlett.o \
mixer_scarlett_gen2.o \
mixer_us16x08.o \
mixer_s1810c.o \
pcm.o \
power.o \
proc.o \

View File

@ -226,6 +226,36 @@ static int parse_audio_format_rates_v1(struct snd_usb_audio *chip, struct audiof
return 0;
}
/*
* Presonus Studio 1810c supports a limited set of sampling
* rates per altsetting but reports the full set each time.
* If we don't filter out the unsupported rates and attempt
* to configure the card, it will hang refusing to do any
* further audio I/O until a hard reset is performed.
*
* The list of supported rates per altsetting (set of available
* I/O channels) is described in the owner's manual, section 2.2.
*/
static bool s1810c_valid_sample_rate(struct audioformat *fp,
unsigned int rate)
{
switch (fp->altsetting) {
case 1:
/* All ADAT ports available */
return rate <= 48000;
case 2:
/* Half of ADAT ports available */
return (rate == 88200 || rate == 96000);
case 3:
/* Analog I/O only (no S/PDIF nor ADAT) */
return rate >= 176400;
default:
return false;
}
return false;
}
/*
* 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
@ -262,6 +292,12 @@ static int parse_uac2_sample_rate_range(struct snd_usb_audio *chip,
}
for (rate = min; rate <= max; rate += res) {
/* Filter out invalid rates on Presonus Studio 1810c */
if (chip->usb_id == USB_ID(0x0194f, 0x010c) &&
!s1810c_valid_sample_rate(fp, rate))
goto skip_rate;
if (fp->rate_table)
fp->rate_table[nr_rates] = rate;
if (!fp->rate_min || rate < fp->rate_min)
@ -276,6 +312,7 @@ static int parse_uac2_sample_rate_range(struct snd_usb_audio *chip,
break;
}
skip_rate:
/* avoid endless loop */
if (res == 0)
break;

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@ -34,6 +34,7 @@
#include "mixer_scarlett.h"
#include "mixer_scarlett_gen2.h"
#include "mixer_us16x08.h"
#include "mixer_s1810c.h"
#include "helper.h"
struct std_mono_table {
@ -2277,6 +2278,10 @@ int snd_usb_mixer_apply_create_quirk(struct usb_mixer_interface *mixer)
case USB_ID(0x2a39, 0x3fd4): /* RME */
err = snd_rme_controls_create(mixer);
break;
case USB_ID(0x0194f, 0x010c): /* Presonus Studio 1810c */
err = snd_sc1810_init_mixer(mixer);
break;
}
return err;

595
sound/usb/mixer_s1810c.c Normal file
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@ -0,0 +1,595 @@
// SPDX-License-Identifier: GPL-2.0
/*
* Presonus Studio 1810c driver for ALSA
* Copyright (C) 2019 Nick Kossifidis <mickflemm@gmail.com>
*
* Based on reverse engineering of the communication protocol
* between the windows driver / Univeral Control (UC) program
* and the device, through usbmon.
*
* For now this bypasses the mixer, with all channels split,
* so that the software can mix with greater flexibility.
* It also adds controls for the 4 buttons on the front of
* the device.
*/
#include <linux/usb.h>
#include <linux/usb/audio-v2.h>
#include <linux/slab.h>
#include <sound/core.h>
#include <sound/control.h>
#include "usbaudio.h"
#include "mixer.h"
#include "mixer_quirks.h"
#include "helper.h"
#include "mixer_s1810c.h"
#define SC1810C_CMD_REQ 160
#define SC1810C_CMD_REQTYPE \
(USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT)
#define SC1810C_CMD_F1 0x50617269
#define SC1810C_CMD_F2 0x14
/*
* DISCLAIMER: These are just guesses based on the
* dumps I got.
*
* It seems like a selects between
* device (0), mixer (0x64) and output (0x65)
*
* For mixer (0x64):
* * b selects an input channel (see below).
* * c selects an output channel pair (see below).
* * d selects left (0) or right (1) of that pair.
* * e 0-> disconnect, 0x01000000-> connect,
* 0x0109-> used for stereo-linking channels,
* e is also used for setting volume levels
* in which case b is also set so I guess
* this way it is possible to set the volume
* level from the specified input to the
* specified output.
*
* IN Channels:
* 0 - 7 Mic/Inst/Line (Analog inputs)
* 8 - 9 S/PDIF
* 10 - 17 ADAT
* 18 - 35 DAW (Inputs from the host)
*
* OUT Channels (pairs):
* 0 -> Main out
* 1 -> Line1/2
* 2 -> Line3/4
* 3 -> S/PDIF
* 4 -> ADAT?
*
* For device (0):
* * b and c are not used, at least not on the
* dumps I got.
* * d sets the control id to be modified
* (see below).
* * e sets the setting for that control.
* (so for the switches I was interested
* in it's 0/1)
*
* For output (0x65):
* * b is the output channel (see above).
* * c is zero.
* * e I guess the same as with mixer except 0x0109
* which I didn't see in my dumps.
*
* The two fixed fields have the same values for
* mixer and output but a different set for device.
*/
struct s1810c_ctl_packet {
u32 a;
u32 b;
u32 fixed1;
u32 fixed2;
u32 c;
u32 d;
u32 e;
};
#define SC1810C_CTL_LINE_SW 0
#define SC1810C_CTL_MUTE_SW 1
#define SC1810C_CTL_AB_SW 3
#define SC1810C_CTL_48V_SW 4
#define SC1810C_SET_STATE_REQ 161
#define SC1810C_SET_STATE_REQTYPE SC1810C_CMD_REQTYPE
#define SC1810C_SET_STATE_F1 0x64656D73
#define SC1810C_SET_STATE_F2 0xF4
#define SC1810C_GET_STATE_REQ 162
#define SC1810C_GET_STATE_REQTYPE \
(USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN)
#define SC1810C_GET_STATE_F1 SC1810C_SET_STATE_F1
#define SC1810C_GET_STATE_F2 SC1810C_SET_STATE_F2
#define SC1810C_STATE_F1_IDX 2
#define SC1810C_STATE_F2_IDX 3
/*
* This packet includes mixer volumes and
* various other fields, it's an extended
* version of ctl_packet, with a and b
* being zero and different f1/f2.
*/
struct s1810c_state_packet {
u32 fields[63];
};
#define SC1810C_STATE_48V_SW 58
#define SC1810C_STATE_LINE_SW 59
#define SC1810C_STATE_MUTE_SW 60
#define SC1810C_STATE_AB_SW 62
struct s1810_mixer_state {
uint16_t seqnum;
struct mutex usb_mutex;
struct mutex data_mutex;
};
static int
snd_s1810c_send_ctl_packet(struct usb_device *dev, u32 a,
u32 b, u32 c, u32 d, u32 e)
{
struct s1810c_ctl_packet pkt = { 0 };
int ret = 0;
pkt.fixed1 = SC1810C_CMD_F1;
pkt.fixed2 = SC1810C_CMD_F2;
pkt.a = a;
pkt.b = b;
pkt.c = c;
pkt.d = d;
/*
* Value for settings 0/1 for this
* output channel is always 0 (probably because
* there is no ADAT output on 1810c)
*/
pkt.e = (c == 4) ? 0 : e;
ret = snd_usb_ctl_msg(dev, usb_sndctrlpipe(dev, 0),
SC1810C_CMD_REQ,
SC1810C_CMD_REQTYPE, 0, 0, &pkt, sizeof(pkt));
if (ret < 0) {
dev_warn(&dev->dev, "could not send ctl packet\n");
return ret;
}
return 0;
}
/*
* When opening Universal Control the program periodicaly
* sends and receives state packets for syncinc state between
* the device and the host.
*
* Note that if we send only the request to get data back we'll
* get an error, we need to first send an empty state packet and
* then ask to receive a filled. Their seqnumbers must also match.
*/
static int
snd_sc1810c_get_status_field(struct usb_device *dev,
u32 *field, int field_idx, uint16_t *seqnum)
{
struct s1810c_state_packet pkt_out = { 0 };
struct s1810c_state_packet pkt_in = { 0 };
int ret = 0;
pkt_out.fields[SC1810C_STATE_F1_IDX] = SC1810C_SET_STATE_F1;
pkt_out.fields[SC1810C_STATE_F2_IDX] = SC1810C_SET_STATE_F2;
ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
SC1810C_SET_STATE_REQ,
SC1810C_SET_STATE_REQTYPE,
(*seqnum), 0, &pkt_out, sizeof(pkt_out));
if (ret < 0) {
dev_warn(&dev->dev, "could not send state packet (%d)\n", ret);
return ret;
}
ret = snd_usb_ctl_msg(dev, usb_rcvctrlpipe(dev, 0),
SC1810C_GET_STATE_REQ,
SC1810C_GET_STATE_REQTYPE,
(*seqnum), 0, &pkt_in, sizeof(pkt_in));
if (ret < 0) {
dev_warn(&dev->dev, "could not get state field %u (%d)\n",
field_idx, ret);
return ret;
}
(*field) = pkt_in.fields[field_idx];
(*seqnum)++;
return 0;
}
/*
* This is what I got when bypassing the mixer with
* all channels split. I'm not 100% sure of what's going
* on, I could probably clean this up based on my observations
* but I prefer to keep the same behavior as the windows driver.
*/
static int snd_s1810c_init_mixer_maps(struct snd_usb_audio *chip)
{
u32 a, b, c, e, n, off;
struct usb_device *dev = chip->dev;
/* Set initial volume levels ? */
a = 0x64;
e = 0xbc;
for (n = 0; n < 2; n++) {
off = n * 18;
for (b = off, c = 0; b < 18 + off; b++) {
/* This channel to all outputs ? */
for (c = 0; c <= 8; c++) {
snd_s1810c_send_ctl_packet(dev, a, b, c, 0, e);
snd_s1810c_send_ctl_packet(dev, a, b, c, 1, e);
}
/* This channel to main output (again) */
snd_s1810c_send_ctl_packet(dev, a, b, 0, 0, e);
snd_s1810c_send_ctl_packet(dev, a, b, 0, 1, e);
}
/*
* I noticed on UC that DAW channels have different
* initial volumes, so this makes sense.
*/
e = 0xb53bf0;
}
/* Connect analog outputs ? */
a = 0x65;
e = 0x01000000;
for (b = 1; b < 3; b++) {
snd_s1810c_send_ctl_packet(dev, a, b, 0, 0, e);
snd_s1810c_send_ctl_packet(dev, a, b, 0, 1, e);
}
snd_s1810c_send_ctl_packet(dev, a, 0, 0, 0, e);
snd_s1810c_send_ctl_packet(dev, a, 0, 0, 1, e);
/* Set initial volume levels for S/PDIF mappings ? */
a = 0x64;
e = 0xbc;
c = 3;
for (n = 0; n < 2; n++) {
off = n * 18;
for (b = off; b < 18 + off; b++) {
snd_s1810c_send_ctl_packet(dev, a, b, c, 0, e);
snd_s1810c_send_ctl_packet(dev, a, b, c, 1, e);
}
e = 0xb53bf0;
}
/* Connect S/PDIF output ? */
a = 0x65;
e = 0x01000000;
snd_s1810c_send_ctl_packet(dev, a, 3, 0, 0, e);
snd_s1810c_send_ctl_packet(dev, a, 3, 0, 1, e);
/* Connect all outputs (again) ? */
a = 0x65;
e = 0x01000000;
for (b = 0; b < 4; b++) {
snd_s1810c_send_ctl_packet(dev, a, b, 0, 0, e);
snd_s1810c_send_ctl_packet(dev, a, b, 0, 1, e);
}
/* Basic routing to get sound out of the device */
a = 0x64;
e = 0x01000000;
for (c = 0; c < 4; c++) {
for (b = 0; b < 36; b++) {
if ((c == 0 && b == 18) || /* DAW1/2 -> Main */
(c == 1 && b == 20) || /* DAW3/4 -> Line3/4 */
(c == 2 && b == 22) || /* DAW4/5 -> Line5/6 */
(c == 3 && b == 24)) { /* DAW5/6 -> S/PDIF */
/* Left */
snd_s1810c_send_ctl_packet(dev, a, b, c, 0, e);
snd_s1810c_send_ctl_packet(dev, a, b, c, 1, 0);
b++;
/* Right */
snd_s1810c_send_ctl_packet(dev, a, b, c, 0, 0);
snd_s1810c_send_ctl_packet(dev, a, b, c, 1, e);
} else {
/* Leave the rest disconnected */
snd_s1810c_send_ctl_packet(dev, a, b, c, 0, 0);
snd_s1810c_send_ctl_packet(dev, a, b, c, 1, 0);
}
}
}
/* Set initial volume levels for S/PDIF (again) ? */
a = 0x64;
e = 0xbc;
c = 3;
for (n = 0; n < 2; n++) {
off = n * 18;
for (b = off; b < 18 + off; b++) {
snd_s1810c_send_ctl_packet(dev, a, b, c, 0, e);
snd_s1810c_send_ctl_packet(dev, a, b, c, 1, e);
}
e = 0xb53bf0;
}
/* Connect S/PDIF outputs (again) ? */
a = 0x65;
e = 0x01000000;
snd_s1810c_send_ctl_packet(dev, a, 3, 0, 0, e);
snd_s1810c_send_ctl_packet(dev, a, 3, 0, 1, e);
/* Again ? */
snd_s1810c_send_ctl_packet(dev, a, 3, 0, 0, e);
snd_s1810c_send_ctl_packet(dev, a, 3, 0, 1, e);
return 0;
}
/*
* Sync state with the device and retrieve the requested field,
* whose index is specified in (kctl->private_value & 0xFF),
* from the received fields array.
*/
static int
snd_s1810c_get_switch_state(struct usb_mixer_interface *mixer,
struct snd_kcontrol *kctl, u32 *state)
{
struct snd_usb_audio *chip = mixer->chip;
struct s1810_mixer_state *private = mixer->private_data;
u32 field = 0;
u32 ctl_idx = (u32) (kctl->private_value & 0xFF);
int ret = 0;
mutex_lock(&private->usb_mutex);
ret = snd_sc1810c_get_status_field(chip->dev, &field,
ctl_idx, &private->seqnum);
if (ret < 0)
goto unlock;
*state = field;
unlock:
mutex_unlock(&private->usb_mutex);
return ret ? ret : 0;
}
/*
* Send a control packet to the device for the control id
* specified in (kctl->private_value >> 8) with value
* specified in (kctl->private_value >> 16).
*/
static int
snd_s1810c_set_switch_state(struct usb_mixer_interface *mixer,
struct snd_kcontrol *kctl)
{
struct snd_usb_audio *chip = mixer->chip;
struct s1810_mixer_state *private = mixer->private_data;
u32 pval = (u32) kctl->private_value;
u32 ctl_id = (pval >> 8) & 0xFF;
u32 ctl_val = (pval >> 16) & 0x1;
int ret = 0;
mutex_lock(&private->usb_mutex);
ret = snd_s1810c_send_ctl_packet(chip->dev, 0, 0, 0, ctl_id, ctl_val);
mutex_unlock(&private->usb_mutex);
return ret;
}
/* Generic get/set/init functions for switch controls */
static int
snd_s1810c_switch_get(struct snd_kcontrol *kctl,
struct snd_ctl_elem_value *ctl_elem)
{
struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
struct usb_mixer_interface *mixer = list->mixer;
struct s1810_mixer_state *private = mixer->private_data;
u32 pval = (u32) kctl->private_value;
u32 ctl_idx = pval & 0xFF;
u32 state = 0;
int ret = 0;
mutex_lock(&private->data_mutex);
ret = snd_s1810c_get_switch_state(mixer, kctl, &state);
if (ret < 0)
goto unlock;
switch (ctl_idx) {
case SC1810C_STATE_LINE_SW:
case SC1810C_STATE_AB_SW:
ctl_elem->value.enumerated.item[0] = (int)state;
break;
default:
ctl_elem->value.integer.value[0] = (long)state;
}
unlock:
mutex_unlock(&private->data_mutex);
return (ret < 0) ? ret : 0;
}
static int
snd_s1810c_switch_set(struct snd_kcontrol *kctl,
struct snd_ctl_elem_value *ctl_elem)
{
struct usb_mixer_elem_list *list = snd_kcontrol_chip(kctl);
struct usb_mixer_interface *mixer = list->mixer;
struct s1810_mixer_state *private = mixer->private_data;
u32 pval = (u32) kctl->private_value;
u32 ctl_idx = pval & 0xFF;
u32 curval = 0;
u32 newval = 0;
int ret = 0;
mutex_lock(&private->data_mutex);
ret = snd_s1810c_get_switch_state(mixer, kctl, &curval);
if (ret < 0)
goto unlock;
switch (ctl_idx) {
case SC1810C_STATE_LINE_SW:
case SC1810C_STATE_AB_SW:
newval = (u32) ctl_elem->value.enumerated.item[0];
break;
default:
newval = (u32) ctl_elem->value.integer.value[0];
}
if (curval == newval)
goto unlock;
kctl->private_value &= ~(0x1 << 16);
kctl->private_value |= (unsigned int)(newval & 0x1) << 16;
ret = snd_s1810c_set_switch_state(mixer, kctl);
unlock:
mutex_unlock(&private->data_mutex);
return (ret < 0) ? 0 : 1;
}
static int
snd_s1810c_switch_init(struct usb_mixer_interface *mixer,
const struct snd_kcontrol_new *new_kctl)
{
struct snd_kcontrol *kctl;
struct usb_mixer_elem_info *elem;
elem = kzalloc(sizeof(struct usb_mixer_elem_info), GFP_KERNEL);
if (!elem)
return -ENOMEM;
elem->head.mixer = mixer;
elem->control = 0;
elem->head.id = 0;
elem->channels = 1;
kctl = snd_ctl_new1(new_kctl, elem);
if (!kctl) {
kfree(elem);
return -ENOMEM;
}
kctl->private_free = snd_usb_mixer_elem_free;
return snd_usb_mixer_add_control(&elem->head, kctl);
}
static int
snd_s1810c_line_sw_info(struct snd_kcontrol *kctl,
struct snd_ctl_elem_info *uinfo)
{
static const char *const texts[2] = {
"Preamp On (Mic/Inst)",
"Preamp Off (Line in)"
};
return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);
}
static const struct snd_kcontrol_new snd_s1810c_line_sw = {
.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
.name = "Line 1/2 Source Type",
.info = snd_s1810c_line_sw_info,
.get = snd_s1810c_switch_get,
.put = snd_s1810c_switch_set,
.private_value = (SC1810C_STATE_LINE_SW | SC1810C_CTL_LINE_SW << 8)
};
static const struct snd_kcontrol_new snd_s1810c_mute_sw = {
.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
.name = "Mute Main Out Switch",
.info = snd_ctl_boolean_mono_info,
.get = snd_s1810c_switch_get,
.put = snd_s1810c_switch_set,
.private_value = (SC1810C_STATE_MUTE_SW | SC1810C_CTL_MUTE_SW << 8)
};
static const struct snd_kcontrol_new snd_s1810c_48v_sw = {
.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
.name = "48V Phantom Power On Mic Inputs Switch",
.info = snd_ctl_boolean_mono_info,
.get = snd_s1810c_switch_get,
.put = snd_s1810c_switch_set,
.private_value = (SC1810C_STATE_48V_SW | SC1810C_CTL_48V_SW << 8)
};
static int
snd_s1810c_ab_sw_info(struct snd_kcontrol *kctl,
struct snd_ctl_elem_info *uinfo)
{
static const char *const texts[2] = {
"1/2",
"3/4"
};
return snd_ctl_enum_info(uinfo, 1, ARRAY_SIZE(texts), texts);
}
static const struct snd_kcontrol_new snd_s1810c_ab_sw = {
.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
.name = "Headphone 1 Source Route",
.info = snd_s1810c_ab_sw_info,
.get = snd_s1810c_switch_get,
.put = snd_s1810c_switch_set,
.private_value = (SC1810C_STATE_AB_SW | SC1810C_CTL_AB_SW << 8)
};
static void snd_sc1810_mixer_state_free(struct usb_mixer_interface *mixer)
{
struct s1810_mixer_state *private = mixer->private_data;
kfree(private);
mixer->private_data = NULL;
}
/* Entry point, called from mixer_quirks.c */
int snd_sc1810_init_mixer(struct usb_mixer_interface *mixer)
{
struct s1810_mixer_state *private = NULL;
struct snd_usb_audio *chip = mixer->chip;
struct usb_device *dev = chip->dev;
int ret = 0;
/* Run this only once */
if (!list_empty(&chip->mixer_list))
return 0;
dev_info(&dev->dev,
"Presonus Studio 1810c, device_setup: %u\n", chip->setup);
if (chip->setup == 1)
dev_info(&dev->dev, "(8out/18in @ 48KHz)\n");
else if (chip->setup == 2)
dev_info(&dev->dev, "(6out/8in @ 192KHz)\n");
else
dev_info(&dev->dev, "(8out/14in @ 96KHz)\n");
ret = snd_s1810c_init_mixer_maps(chip);
if (ret < 0)
return ret;
private = kzalloc(sizeof(struct s1810_mixer_state), GFP_KERNEL);
if (!private)
return -ENOMEM;
mutex_init(&private->usb_mutex);
mutex_init(&private->data_mutex);
mixer->private_data = private;
mixer->private_free = snd_sc1810_mixer_state_free;
private->seqnum = 1;
ret = snd_s1810c_switch_init(mixer, &snd_s1810c_line_sw);
if (ret < 0)
return ret;
ret = snd_s1810c_switch_init(mixer, &snd_s1810c_mute_sw);
if (ret < 0)
return ret;
ret = snd_s1810c_switch_init(mixer, &snd_s1810c_48v_sw);
if (ret < 0)
return ret;
ret = snd_s1810c_switch_init(mixer, &snd_s1810c_ab_sw);
if (ret < 0)
return ret;
return ret;
}

7
sound/usb/mixer_s1810c.h Normal file
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@ -0,0 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Presonus Studio 1810c driver for ALSA
* Copyright (C) 2019 Nick Kossifidis <mickflemm@gmail.com>
*/
int snd_sc1810_init_mixer(struct usb_mixer_interface *mixer);

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@ -1252,6 +1252,38 @@ static int fasttrackpro_skip_setting_quirk(struct snd_usb_audio *chip,
return 0; /* keep this altsetting */
}
static int s1810c_skip_setting_quirk(struct snd_usb_audio *chip,
int iface, int altno)
{
/*
* Altno settings:
*
* Playback (Interface 1):
* 1: 6 Analog + 2 S/PDIF
* 2: 6 Analog + 2 S/PDIF
* 3: 6 Analog
*
* Capture (Interface 2):
* 1: 8 Analog + 2 S/PDIF + 8 ADAT
* 2: 8 Analog + 2 S/PDIF + 4 ADAT
* 3: 8 Analog
*/
/*
* I'll leave 2 as the default one and
* use device_setup to switch to the
* other two.
*/
if ((chip->setup == 0 || chip->setup > 2) && altno != 2)
return 1;
else if (chip->setup == 1 && altno != 1)
return 1;
else if (chip->setup == 2 && altno != 3)
return 1;
return 0;
}
int snd_usb_apply_interface_quirk(struct snd_usb_audio *chip,
int iface,
int altno)
@ -1265,6 +1297,10 @@ int snd_usb_apply_interface_quirk(struct snd_usb_audio *chip,
/* fasttrackpro usb: skip altsets incompatible with device_setup */
if (chip->usb_id == USB_ID(0x0763, 0x2012))
return fasttrackpro_skip_setting_quirk(chip, iface, altno);
/* presonus studio 1810c: skip altsets incompatible with device_setup */
if (chip->usb_id == USB_ID(0x0194f, 0x010c))
return s1810c_skip_setting_quirk(chip, iface, altno);
return 0;
}