1 files changed, 143 insertions, 102 deletions

diff --git a/sound/usb/mixer.c b/sound/usb/mixer.c
index 03ce971e0027..736d134cc03c 100644
--- a/sound/usb/mixer.c
+++ b/sound/usb/mixer.c
@@ -78,39 +78,6 @@ enum {
         USB_MIXER_U16,
 };
 
-enum {
-        USB_PROC_UPDOWN = 1,
-        USB_PROC_UPDOWN_SWITCH = 1,
-        USB_PROC_UPDOWN_MODE_SEL = 2,
-
-        USB_PROC_PROLOGIC = 2,
-        USB_PROC_PROLOGIC_SWITCH = 1,
-        USB_PROC_PROLOGIC_MODE_SEL = 2,
-
-        USB_PROC_3DENH = 3,
-        USB_PROC_3DENH_SWITCH = 1,
-        USB_PROC_3DENH_SPACE = 2,
-
-        USB_PROC_REVERB = 4,
-        USB_PROC_REVERB_SWITCH = 1,
-        USB_PROC_REVERB_LEVEL = 2,
-        USB_PROC_REVERB_TIME = 3,
-        USB_PROC_REVERB_DELAY = 4,
-
-        USB_PROC_CHORUS = 5,
-        USB_PROC_CHORUS_SWITCH = 1,
-        USB_PROC_CHORUS_LEVEL = 2,
-        USB_PROC_CHORUS_RATE = 3,
-        USB_PROC_CHORUS_DEPTH = 4,
-
-        USB_PROC_DCR = 6,
-        USB_PROC_DCR_SWITCH = 1,
-        USB_PROC_DCR_RATIO = 2,
-        USB_PROC_DCR_MAX_AMP = 3,
-        USB_PROC_DCR_THRESHOLD = 4,
-        USB_PROC_DCR_ATTACK = 5,
-        USB_PROC_DCR_RELEASE = 6,
-};
 
 /*E-mu 0202(0404) eXtension Unit(XU) control*/
 enum {
@@ -198,22 +165,24 @@ 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)
 {
-        unsigned char *p;
+        /* we just parse the header */
+        struct uac_feature_unit_descriptor *hdr = NULL;
 
-        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] <= UAC2_EXTENSION_UNIT_V2 && p[3] == unit)
-                        return p;
+        while ((hdr = snd_usb_find_desc(state->buffer, state->buflen, hdr,
+                                        USB_DT_CS_INTERFACE)) != NULL) {
+                if (hdr->bLength >= 4 &&
+                    hdr->bDescriptorSubtype >= UAC_INPUT_TERMINAL &&
+                    hdr->bDescriptorSubtype <= UAC2_SAMPLE_RATE_CONVERTER &&
+                    hdr->bUnitID == unit)
+                        return hdr;
         }
+
         return NULL;
 }
 
-
 /*
  * copy a string with the given id
  */
@@ -328,27 +297,36 @@ static int get_ctl_value_v1(struct usb_mixer_elem_info *cval, int request, int v
 
 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 buf[2 + 3*sizeof(__u16)]; /* enough space for one range */
         unsigned char *val;
-        int ret;
+        int ret, size;
         __u8 bRequest;
 
-        bRequest = (request == UAC_GET_CUR) ?
-                UAC2_CS_CUR : UAC2_CS_RANGE;
+        if (request == UAC_GET_CUR) {
+                bRequest = UAC2_CS_CUR;
+                size = sizeof(__u16);
+        } else {
+                bRequest = UAC2_CS_RANGE;
+                size = sizeof(buf);
+        }
+
+        memset(buf, 0, sizeof(buf));
 
         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);
+                              buf, size, 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);
+                snd_printk(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;
         }
 
+        /* FIXME: how should we handle multiple triplets here? */
+
         switch (request) {
         case UAC_GET_CUR:
                 val = buf;
@@ -462,6 +440,16 @@ static int set_cur_mix_value(struct usb_mixer_elem_info *cval, int channel,
                              int index, int value)
 {
         int err;
+        unsigned int read_only = (channel == 0) ?
+                cval->master_readonly :
+                cval->ch_readonly & (1 << (channel - 1));
+
+        if (read_only) {
+                snd_printdd(KERN_INFO "%s(): channel %d of control %d is read_only\n",
+                            __func__, channel, cval->control);
+                return 0;
+        }
+
         err = snd_usb_mixer_set_ctl_value(cval, UAC_SET_CUR, (cval->control << 8) | channel,
                             value);
         if (err < 0)
@@ -631,6 +619,7 @@ 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)
 {
+        int err;
         void *p1;
 
         memset(term, 0, sizeof(*term));
@@ -651,6 +640,11 @@ static int check_input_term(struct mixer_build *state, int id, struct usb_audio_
                                 term->channels = d->bNrChannels;
                                 term->chconfig = le32_to_cpu(d->bmChannelConfig);
                                 term->name = d->iTerminal;
+
+                                /* call recursively to get the clock selectors */
+                                err = check_input_term(state, d->bCSourceID, term);
+                                if (err < 0)
+                                        return err;
                         }
                         return 0;
                 case UAC_FEATURE_UNIT: {
@@ -667,7 +661,8 @@ static int check_input_term(struct mixer_build *state, int id, struct usb_audio_
                         term->name = uac_mixer_unit_iMixer(d);
                         return 0;
                 }
-                case UAC_SELECTOR_UNIT: {
+                case UAC_SELECTOR_UNIT:
+                case UAC2_CLOCK_SELECTOR: {
                         struct uac_selector_unit_descriptor *d = p1;
                         /* call recursively to retrieve the channel info */
                         if (check_input_term(state, d->baSourceID[0], term) < 0)
@@ -690,6 +685,13 @@ static int check_input_term(struct mixer_build *state, int id, struct usb_audio_
                         term->name = uac_processing_unit_iProcessing(d, state->mixer->protocol);
                         return 0;
                 }
+                case UAC2_CLOCK_SOURCE: {
+                        struct uac_clock_source_descriptor *d = p1;
+                        term->type = d->bDescriptorSubtype << 16; /* virtual type */
+                        term->id = id;
+                        term->name = d->iClockSource;
+                        return 0;
+                }
                 default:
                         return -ENODEV;
                 }
@@ -709,16 +711,20 @@ struct usb_feature_control_info {
 };
 
 static struct usb_feature_control_info audio_feature_info[] = {
-        { "Mute",               USB_MIXER_INV_BOOLEAN },
-        { "Volume",             USB_MIXER_S16 },
+        { "Mute",                       USB_MIXER_INV_BOOLEAN },
+        { "Volume",                     USB_MIXER_S16 },
         { "Tone Control - Bass",        USB_MIXER_S8 },
         { "Tone Control - Mid",         USB_MIXER_S8 },
         { "Tone Control - Treble",      USB_MIXER_S8 },
         { "Graphic Equalizer",          USB_MIXER_S8 }, /* FIXME: not implemeted yet */
-        { "Auto Gain Control",  USB_MIXER_BOOLEAN },
-        { "Delay Control",      USB_MIXER_U16 },
-        { "Bass Boost",         USB_MIXER_BOOLEAN },
-        { "Loudness",           USB_MIXER_BOOLEAN },
+        { "Auto Gain Control",          USB_MIXER_BOOLEAN },
+        { "Delay Control",              USB_MIXER_U16 },
+        { "Bass Boost",                 USB_MIXER_BOOLEAN },
+        { "Loudness",                   USB_MIXER_BOOLEAN },
+        /* UAC2 specific */
+        { "Input Gain Control",         USB_MIXER_U16 },
+        { "Input Gain Pad Control",     USB_MIXER_BOOLEAN },
+        { "Phase Inverter Control",     USB_MIXER_BOOLEAN },
 };
 
 
@@ -958,7 +964,7 @@ 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,
-                              int read_only)
+                              int readonly_mask)
 {
         struct uac_feature_unit_descriptor *desc = raw_desc;
         unsigned int len = 0;
@@ -970,7 +976,7 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
 
         control++; /* change from zero-based to 1-based value */
 
-        if (control == UAC_GRAPHIC_EQUALIZER_CONTROL) {
+        if (control == UAC_FU_GRAPHIC_EQUALIZER) {
                 /* FIXME: not supported yet */
                 return;
         }
@@ -989,20 +995,25 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
         cval->control = control;
         cval->cmask = ctl_mask;
         cval->val_type = audio_feature_info[control-1].type;
-        if (ctl_mask == 0)
+        if (ctl_mask == 0) {
                 cval->channels = 1;     /* master channel */
-        else {
+                cval->master_readonly = readonly_mask;
+        } else {
                 int i, c = 0;
                 for (i = 0; i < 16; i++)
                         if (ctl_mask & (1 << i))
                                 c++;
                 cval->channels = c;
+                cval->ch_readonly = readonly_mask;
         }
 
         /* get min/max values */
         get_min_max(cval, 0);
 
-        if (read_only)
+        /* if all channels in the mask are marked read-only, make the control
+         * read-only. set_cur_mix_value() will check the mask again and won't
+         * issue write commands to read-only channels. */
+        if (cval->channels == readonly_mask)
                 kctl = snd_ctl_new1(&usb_feature_unit_ctl_ro, cval);
         else
                 kctl = snd_ctl_new1(&usb_feature_unit_ctl, cval);
@@ -1021,8 +1032,8 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
                                 kctl->id.name, sizeof(kctl->id.name));
 
         switch (control) {
-        case UAC_MUTE_CONTROL:
-        case UAC_VOLUME_CONTROL:
+        case UAC_FU_MUTE:
+        case UAC_FU_VOLUME:
                 /* determine the control name.  the rule is:
                  * - if a name id is given in descriptor, use it.
                  * - if the connected input can be determined, then use the name
@@ -1049,9 +1060,9 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
                                 len = append_ctl_name(kctl, " Playback");
                         }
                 }
-                append_ctl_name(kctl, control == UAC_MUTE_CONTROL ?
+                append_ctl_name(kctl, control == UAC_FU_MUTE ?
                                 " Switch" : " Volume");
-                if (control == UAC_VOLUME_CONTROL) {
+                if (control == UAC_FU_VOLUME) {
                         kctl->tlv.c = mixer_vol_tlv;
                         kctl->vd[0].access |= 
                                 SNDRV_CTL_ELEM_ACCESS_TLV_READ |
@@ -1096,6 +1107,19 @@ static void build_feature_ctl(struct mixer_build *state, void *raw_desc,
                 }
                 break;
 
+        case USB_ID(0x046d, 0x0809):
+        case USB_ID(0x046d, 0x0991):
+        /* Most audio usb devices lie about volume resolution.
+         * Most Logitech webcams have res = 384.
+         * Proboly there is some logitech magic behind this number --fishor
+         */
+                if (!strcmp(kctl->id.name, "Mic Capture Volume")) {
+                        snd_printk(KERN_INFO
+                                "set resolution quirk: cval->res = 384\n");
+                        cval->res = 384;
+                }
+                break;
+
         }
 
         snd_printdd(KERN_INFO "[%d] FU [%s] ch = %d, val = %d/%d/%d\n",
@@ -1150,7 +1174,7 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid, void
                 snd_printk(KERN_INFO
                            "usbmixer: master volume quirk for PCM2702 chip\n");
                 /* disable non-functional volume control */
-                master_bits &= ~UAC_FU_VOLUME;
+                master_bits &= ~UAC_CONTROL_BIT(UAC_FU_VOLUME);
                 break;
         }
         if (channels > 0)
@@ -1188,19 +1212,22 @@ static int parse_audio_feature_unit(struct mixer_build *state, int unitid, void
 
                         for (j = 0; j < channels; j++) {
                                 unsigned int mask = snd_usb_combine_bytes(bmaControls + csize * (j+1), csize);
-                                if (mask & (1 << (i * 2))) {
+                                if (uac2_control_is_readable(mask, i)) {
                                         ch_bits |= (1 << j);
-                                        if (~mask & (1 << ((i * 2) + 1)))
+                                        if (!uac2_control_is_writeable(mask, i))
                                                 ch_read_only |= (1 << j);
                                 }
                         }
 
-                        /* FIXME: the whole unit is read-only if any of the channels is marked read-only */
+                        /* NOTE: build_feature_ctl() will mark the control read-only if all channels
+                         * are marked read-only in the descriptors. Otherwise, the control will be
+                         * reported as writeable, but the driver will not actually issue a write
+                         * command for read-only channels */
                         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, ch_bits, i, &iterm, unitid, ch_read_only);
+                        if (uac2_control_is_readable(master_bits, i))
                                 build_feature_ctl(state, _ftr, 0, i, &iterm, unitid,
-                                                  ~master_bits & (1 << ((i * 2) + 1)));
+                                                  !uac2_control_is_writeable(master_bits, i));
                 }
         }
 
@@ -1392,51 +1419,51 @@ struct procunit_info {
 };
 
 static struct procunit_value_info updown_proc_info[] = {
-        { USB_PROC_UPDOWN_SWITCH, "Switch", USB_MIXER_BOOLEAN },
-        { USB_PROC_UPDOWN_MODE_SEL, "Mode Select", USB_MIXER_U8, 1 },
+        { UAC_UD_ENABLE, "Switch", USB_MIXER_BOOLEAN },
+        { UAC_UD_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
         { 0 }
 };
 static struct procunit_value_info prologic_proc_info[] = {
-        { USB_PROC_PROLOGIC_SWITCH, "Switch", USB_MIXER_BOOLEAN },
-        { USB_PROC_PROLOGIC_MODE_SEL, "Mode Select", USB_MIXER_U8, 1 },
+        { UAC_DP_ENABLE, "Switch", USB_MIXER_BOOLEAN },
+        { UAC_DP_MODE_SELECT, "Mode Select", USB_MIXER_U8, 1 },
         { 0 }
 };
 static struct procunit_value_info threed_enh_proc_info[] = {
-        { USB_PROC_3DENH_SWITCH, "Switch", USB_MIXER_BOOLEAN },
-        { USB_PROC_3DENH_SPACE, "Spaciousness", USB_MIXER_U8 },
+        { UAC_3D_ENABLE, "Switch", USB_MIXER_BOOLEAN },
+        { UAC_3D_SPACE, "Spaciousness", USB_MIXER_U8 },
         { 0 }
 };
 static struct procunit_value_info reverb_proc_info[] = {
-        { USB_PROC_REVERB_SWITCH, "Switch", USB_MIXER_BOOLEAN },
-        { USB_PROC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
-        { USB_PROC_REVERB_TIME, "Time", USB_MIXER_U16 },
-        { USB_PROC_REVERB_DELAY, "Delay", USB_MIXER_U8 },
+        { UAC_REVERB_ENABLE, "Switch", USB_MIXER_BOOLEAN },
+        { UAC_REVERB_LEVEL, "Level", USB_MIXER_U8 },
+        { UAC_REVERB_TIME, "Time", USB_MIXER_U16 },
+        { UAC_REVERB_FEEDBACK, "Feedback", USB_MIXER_U8 },
         { 0 }
 };
 static struct procunit_value_info chorus_proc_info[] = {
-        { USB_PROC_CHORUS_SWITCH, "Switch", USB_MIXER_BOOLEAN },
-        { USB_PROC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
-        { USB_PROC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
-        { USB_PROC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
+        { UAC_CHORUS_ENABLE, "Switch", USB_MIXER_BOOLEAN },
+        { UAC_CHORUS_LEVEL, "Level", USB_MIXER_U8 },
+        { UAC_CHORUS_RATE, "Rate", USB_MIXER_U16 },
+        { UAC_CHORUS_DEPTH, "Depth", USB_MIXER_U16 },
         { 0 }
 };
 static struct procunit_value_info dcr_proc_info[] = {
-        { USB_PROC_DCR_SWITCH, "Switch", USB_MIXER_BOOLEAN },
-        { USB_PROC_DCR_RATIO, "Ratio", USB_MIXER_U16 },
-        { USB_PROC_DCR_MAX_AMP, "Max Amp", USB_MIXER_S16 },
-        { USB_PROC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
-        { USB_PROC_DCR_ATTACK, "Attack Time", USB_MIXER_U16 },
-        { USB_PROC_DCR_RELEASE, "Release Time", USB_MIXER_U16 },
+        { UAC_DCR_ENABLE, "Switch", USB_MIXER_BOOLEAN },
+        { UAC_DCR_RATE, "Ratio", USB_MIXER_U16 },
+        { UAC_DCR_MAXAMPL, "Max Amp", USB_MIXER_S16 },
+        { UAC_DCR_THRESHOLD, "Threshold", USB_MIXER_S16 },
+        { UAC_DCR_ATTACK_TIME, "Attack Time", USB_MIXER_U16 },
+        { UAC_DCR_RELEASE_TIME, "Release Time", USB_MIXER_U16 },
         { 0 }
 };
 
 static struct procunit_info procunits[] = {
-        { USB_PROC_UPDOWN, "Up Down", updown_proc_info },
-        { USB_PROC_PROLOGIC, "Dolby Prologic", prologic_proc_info },
-        { USB_PROC_3DENH, "3D Stereo Extender", threed_enh_proc_info },
-        { USB_PROC_REVERB, "Reverb", reverb_proc_info },
-        { USB_PROC_CHORUS, "Chorus", chorus_proc_info },
-        { USB_PROC_DCR, "DCR", dcr_proc_info },
+        { UAC_PROCESS_UP_DOWNMIX, "Up Down", updown_proc_info },
+        { UAC_PROCESS_DOLBY_PROLOGIC, "Dolby Prologic", prologic_proc_info },
+        { UAC_PROCESS_STEREO_EXTENDER, "3D Stereo Extender", threed_enh_proc_info },
+        { UAC_PROCESS_REVERB, "Reverb", reverb_proc_info },
+        { UAC_PROCESS_CHORUS, "Chorus", chorus_proc_info },
+        { UAC_PROCESS_DYN_RANGE_COMP, "DCR", dcr_proc_info },
         { 0 },
 };
 /*
@@ -1524,7 +1551,7 @@ static int build_audio_procunit(struct mixer_build *state, int unitid, void *raw
                 cval->channels = 1;
 
                 /* get min/max values */
-                if (type == USB_PROC_UPDOWN && cval->control == USB_PROC_UPDOWN_MODE_SEL) {
+                if (type == UAC_PROCESS_UP_DOWNMIX && cval->control == UAC_UD_MODE_SELECT) {
                         __u8 *control_spec = uac_processing_unit_specific(desc, state->mixer->protocol);
                         /* FIXME: hard-coded */
                         cval->min = 1;
@@ -1619,7 +1646,7 @@ static int mixer_ctl_selector_get(struct snd_kcontrol *kcontrol, struct snd_ctl_
         struct usb_mixer_elem_info *cval = kcontrol->private_data;
         int val, err;
 
-        err = get_cur_ctl_value(cval, 0, &val);
+        err = get_cur_ctl_value(cval, cval->control << 8, &val);
         if (err < 0) {
                 if (cval->mixer->ignore_ctl_error) {
                         ucontrol->value.enumerated.item[0] = 0;
@@ -1638,7 +1665,7 @@ static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol, struct snd_ctl_
         struct usb_mixer_elem_info *cval = kcontrol->private_data;
         int val, oval, err;
 
-        err = get_cur_ctl_value(cval, 0, &oval);
+        err = get_cur_ctl_value(cval, cval->control << 8, &oval);
         if (err < 0) {
                 if (cval->mixer->ignore_ctl_error)
                         return 0;
@@ -1647,7 +1674,7 @@ static int mixer_ctl_selector_put(struct snd_kcontrol *kcontrol, struct snd_ctl_
         val = ucontrol->value.enumerated.item[0];
         val = get_abs_value(cval, val);
         if (val != oval) {
-                set_cur_ctl_value(cval, 0, val);
+                set_cur_ctl_value(cval, cval->control << 8, val);
                 return 1;
         }
         return 0;
@@ -1729,6 +1756,11 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid, void
         cval->res = 1;
         cval->initialized = 1;
 
+        if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR)
+                cval->control = UAC2_CX_CLOCK_SELECTOR;
+        else
+                cval->control = 0;
+
         namelist = kmalloc(sizeof(char *) * desc->bNrInPins, GFP_KERNEL);
         if (! namelist) {
                 snd_printk(KERN_ERR "cannot malloc\n");
@@ -1778,7 +1810,9 @@ static int parse_audio_selector_unit(struct mixer_build *state, int unitid, void
                 if (! len)
                         strlcpy(kctl->id.name, "USB", sizeof(kctl->id.name));
 
-                if ((state->oterm.type & 0xff00) == 0x0100)
+                if (desc->bDescriptorSubtype == UAC2_CLOCK_SELECTOR)
+                        append_ctl_name(kctl, " Clock Source");
+                else if ((state->oterm.type & 0xff00) == 0x0100)
                         append_ctl_name(kctl, " Capture Source");
                 else
                         append_ctl_name(kctl, " Playback Source");
@@ -1812,10 +1846,12 @@ static int parse_audio_unit(struct mixer_build *state, int unitid)
 
         switch (p1[2]) {
         case UAC_INPUT_TERMINAL:
+        case UAC2_CLOCK_SOURCE:
                 return 0; /* NOP */
         case UAC_MIXER_UNIT:
                 return parse_audio_mixer_unit(state, unitid, p1);
         case UAC_SELECTOR_UNIT:
+        case UAC2_CLOCK_SELECTOR:
                 return parse_audio_selector_unit(state, unitid, p1);
         case UAC_FEATURE_UNIT:
                 return parse_audio_feature_unit(state, unitid, p1);
@@ -1912,6 +1948,11 @@ static int snd_usb_mixer_controls(struct usb_mixer_interface *mixer)
                         err = parse_audio_unit(&state, desc->bSourceID);
                         if (err < 0)
                                 return err;
+
+                        /* for UAC2, use the same approach to also add the clock selectors */
+                        err = parse_audio_unit(&state, desc->bCSourceID);
+                        if (err < 0)
+                                return err;
                 }
         }