[furuta@usbserv ~]$ dmesg
-- snip other logs --
[291222.978777] usb 2-1.5: new full speed USB device using ehci_hcd and address 4
[291223.131777] usb 2-1.5: New USB device found, idVendor=147a, idProduct=e05b
[291223.131782] usb 2-1.5: New USB device strings: Mfr=1, Product=2, SerialNumber=0
[291223.131786] usb 2-1.5: Product: AS301DTS+ USB AUDIO
[291223.131788] usb 2-1.5: Manufacturer: Formosa21 Inc.
[291223.655641] input: Formosa21 Inc. AS301DTS+ USB AUDIO as /devices/pci0000:00/0000:00:1d.0/usb2/2-1/2-1.5/2-1.5:1.3/input/input5
[291223.655791] generic-usb 0003:147A:E05B.0002: input,hidraw1: USB HID v1.00 Device [Formosa21 Inc. AS301DTS+ USB AUDIO] on usb-0000:00:1d.0-1.5/input3
[291223.719596] ALSA sound/usb/clock.c:219: 4:1:3: endpoint lacks sample rate attribute bit, cannot set.
[291223.775390] usbcore: registered new interface driver snd-usb-audio
[291223.960442] ALSA sound/usb/urb.c:838: cannot submit datapipe for urb 0, error -28: not enough bandwidth
[furuta@usbserv ~]$
[furuta@usbserv /proc]$ cd asound/
[furuta@usbserv /proc/asound]$ ls
AUDIO  PCH  card0  card1  cards  devices  hwdep  modules  oss  pcm  seq  timers  version
[furuta@usbserv /proc/asound]$ ls -la
���v 0
dr-xr-xr-x   6 root root 0 2015-09-21 11:50 .
dr-xr-xr-x 238 root root 0 2015-09-18 11:37 ..
lrwxrwxrwx   1 root root 5 2015-09-21 11:50 AUDIO -> card1
lrwxrwxrwx   1 root root 5 2015-09-21 11:50 PCH -> card0
dr-xr-xr-x   8 root root 0 2015-09-21 11:50 card0
dr-xr-xr-x   4 root root 0 2015-09-21 11:50 card1
-r--r--r--   1 root root 0 2015-09-21 11:50 cards
-r--r--r--   1 root root 0 2015-09-21 11:50 devices
-r--r--r--   1 root root 0 2015-09-21 11:50 hwdep
-r--r--r--   1 root root 0 2015-09-21 11:50 modules
dr-xr-xr-x   2 root root 0 2015-09-21 11:50 oss
-r--r--r--   1 root root 0 2015-09-21 11:50 pcm
dr-xr-xr-x   2 root root 0 2015-09-21 11:50 seq
-r--r--r--   1 root root 0 2015-09-21 11:50 timers
-r--r--r--   1 root root 0 2015-09-21 11:50 version
[furuta@usbserv /proc/asound]$ cd AUDIO/
[furuta@usbserv /proc/asound/AUDIO]$ ls -la
���v 0
dr-xr-xr-x 4 root root 0 2015-09-21 11:51 .
dr-xr-xr-x 6 root root 0 2015-09-21 11:50 ..
-r--r--r-- 1 root root 0 2015-09-21 11:51 id
dr-xr-xr-x 3 root root 0 2015-09-21 11:51 pcm0c
dr-xr-xr-x 3 root root 0 2015-09-21 11:51 pcm0p
-r--r--r-- 1 root root 0 2015-09-21 11:51 stream0
-r--r--r-- 1 root root 0 2015-09-21 11:51 usbbus
-r--r--r-- 1 root root 0 2015-09-21 11:51 usbid
-r--r--r-- 1 root root 0 2015-09-21 11:51 usbmixer
[furuta@usbserv /proc/asound/AUDIO]$ cat id
AUDIO
[furuta@usbserv /proc/asound/AUDIO]$ cat stream0
Formosa21 Inc. AS301DTS+ USB AUDIO at usb-0000:00:1d.0-1.5, full speed : USB Audio

Playback:
  Status: Stop
  Interface 1
    Altset 1
    Format: S16_LE
    Channels: 2
    Endpoint: 1 OUT (ADAPTIVE)
    Rates: 48000, 44100
  Interface 1
    Altset 2
    Format: S24_3LE
    Channels: 2
    Endpoint: 1 OUT (ADAPTIVE)
    Rates: 48000, 44100
  Interface 1
    Altset 3
    Format: S16_LE
    Channels: 2
    Endpoint: 1 OUT (ADAPTIVE)
    Rates: 96000
  Interface 1
    Altset 4
    Format: S24_3LE
    Channels: 2
    Endpoint: 1 OUT (ADAPTIVE)
    Rates: 96000

Capture:
  Status: Stop
  Interface 2
    Altset 1
    Format: S16_LE
    Channels: 2
    Endpoint: 2 IN (ASYNC)
    Rates: 48000, 44100
  Interface 2
    Altset 2
    Format: S24_3LE
    Channels: 2
    Endpoint: 2 IN (ASYNC)
    Rates: 48000, 44100
  Interface 2
    Altset 3
    Format: S16_LE
    Channels: 2
    Endpoint: 2 IN (ASYNC)
    Rates: 96000
  Interface 2
    Altset 4
    Format: S24_3LE
    Channels: 2
    Endpoint: 2 IN (ASYNC)
    Rates: 96000
[furuta@usbserv /proc/asound/AUDIO]$ cat usbbus
002/004
[furuta@usbserv /proc/asound/AUDIO]$ cat usbid
147a:e05b
[furuta@usbserv /proc/asound/AUDIO]$ cat usbmixer
USB Mixer: usb_id=0x147ae05b, ctrlif=0, ctlerr=0
Card: Formosa21 Inc. AS301DTS+ USB AUDIO at usb-0000:00:1d.0-1.5, full speed
  Unit: 6
    Control: name="PCM Playback Volume", index=0
    Info: id=6, control=2, cmask=0x3, channels=2, type="S16"
    Volume: min=-12800, max=0, dBmin=-5000, dBmax=0
  Unit: 6
    Control: name="PCM Playback Switch", index=0
    Info: id=6, control=1, cmask=0x0, channels=1, type="INV_BOOLEAN"
    Volume: min=0, max=1, dBmin=0, dBmax=0
  Unit: 9
    Control: name="Mic Capture Volume", index=0
    Info: id=9, control=2, cmask=0x3, channels=2, type="S16"
    Volume: min=0, max=7680, dBmin=0, dBmax=3000
  Unit: 9
    Control: name="Mic Capture Switch", index=0
    Info: id=9, control=1, cmask=0x0, channels=1, type="INV_BOOLEAN"
    Volume: min=0, max=1, dBmin=0, dBmax=0

[root@usbserv /proc/asound/AUDIO]# lsusb -v
-- snip other devices --
Bus 002 Device 004: ID 147a:e05b Formosa Industrial Computing, Inc.
Device Descriptor:
  bLength                18
  bDescriptorType         1
  bcdUSB               2.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0
  bDeviceProtocol         0
  bMaxPacketSize0        64
  idVendor           0x147a Formosa Industrial Computing, Inc.
  idProduct          0xe05b
  bcdDevice            1.00
  iManufacturer           1 Formosa21 Inc.
  iProduct                2 AS301DTS+ USB AUDIO
  iSerial                 0
  bNumConfigurations      1
  Configuration Descriptor:
    bLength                 9
    bDescriptorType         2
    wTotalLength          485
    bNumInterfaces          4
    bConfigurationValue     1
    iConfiguration          0
    bmAttributes         0xa0
      (Bus Powered)
      Remote Wakeup
    MaxPower              100mA
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        0
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      1 Control Device
      bInterfaceProtocol      0
      iInterface              0
      AudioControl Interface Descriptor:
	bLength                10
	bDescriptorType        36
	bDescriptorSubtype      1 (HEADER)
	bcdADC               1.00
	wTotalLength           84
	bInCollection           2
	baInterfaceNr( 0)       1
	baInterfaceNr( 1)       2
      AudioControl Interface Descriptor:
	bLength                12
	bDescriptorType        36
	bDescriptorSubtype      2 (INPUT_TERMINAL)
	bTerminalID             1
	wTerminalType      0x0101 USB Streaming
	bAssocTerminal          0
	bNrChannels             2
	wChannelConfig     0x0003
	  Left Front (L)
	  Right Front (R)
	iChannelNames           0
	iTerminal               0
      AudioControl Interface Descriptor:
	bLength                12
	bDescriptorType        36
	bDescriptorSubtype      2 (INPUT_TERMINAL)
	bTerminalID             2
	wTerminalType      0x0201 Microphone
	bAssocTerminal          0
	bNrChannels             2
	wChannelConfig     0x0003
	  Left Front (L)
	  Right Front (R)
	iChannelNames           0
	iTerminal               0
      AudioControl Interface Descriptor:
	bLength                 9
	bDescriptorType        36
	bDescriptorSubtype      3 (OUTPUT_TERMINAL)
	bTerminalID             3
	wTerminalType      0x0301 Speaker
	bAssocTerminal          0
	bSourceID               6
	iTerminal               0
      AudioControl Interface Descriptor:
	bLength                 9
	bDescriptorType        36
	bDescriptorSubtype      3 (OUTPUT_TERMINAL)
	bTerminalID             4
	wTerminalType      0x0101 USB Streaming
	bAssocTerminal          0
	bSourceID              13
	iTerminal               0
      AudioControl Interface Descriptor:
	bLength                10
	bDescriptorType        36
	bDescriptorSubtype      6 (FEATURE_UNIT)
	bUnitID                 6
	bSourceID               1
	bControlSize            1
	bmaControls( 0)      0x01
	  Mute Control
	bmaControls( 1)      0x02
	  Volume Control
	bmaControls( 2)      0x02
	  Volume Control
	iFeature                0
      AudioControl Interface Descriptor:
	bLength                10
	bDescriptorType        36
	bDescriptorSubtype      6 (FEATURE_UNIT)
	bUnitID                 9
	bSourceID               2
	bControlSize            1
	bmaControls( 0)      0x01
	  Mute Control
	bmaControls( 1)      0x02
	  Volume Control
	bmaControls( 2)      0x02
	  Volume Control
	iFeature                0
      AudioControl Interface Descriptor:
	bLength                12
	bDescriptorType        36
	bDescriptorSubtype      4 (MIXER_UNIT)
	bUnitID                13
	bNrInPins               1
	baSourceID( 0)          9
	bNrChannels             2
	wChannelConfig     0x0003
	  Left Front (L)
	  Right Front (R)
	iChannelNames           0
	bmControls         0x00
	iMixer                  0
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       1
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
	bLength                 7
	bDescriptorType        36
	bDescriptorSubtype      1 (AS_GENERAL)
	bTerminalLink           1
	bDelay                  1 frames
	wFormatTag              1 PCM
      AudioStreaming Interface Descriptor:
	bLength                14
	bDescriptorType        36
	bDescriptorSubtype      2 (FORMAT_TYPE)
	bFormatType             1 (FORMAT_TYPE_I)
	bNrChannels             2
	bSubframeSize           2
	bBitResolution         16
	bSamFreqType            2 Discrete
	tSamFreq[ 0]        48000
	tSamFreq[ 1]        44100
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x01  EP 1 OUT
	bmAttributes            9
	  Transfer Type            Isochronous
	  Synch Type               Adaptive
	  Usage Type               Data
	wMaxPacketSize     0x00c0  1x 192 bytes
	bInterval               1
	AudioControl Endpoint Descriptor:
	  bLength                 7
	  bDescriptorType        37
	  bDescriptorSubtype      1 (EP_GENERAL)
	  bmAttributes         0x01
	    Sampling Frequency
	  bLockDelayUnits         1 Milliseconds
	  wLockDelay              1 Milliseconds
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       2
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
	bLength                 7
	bDescriptorType        36
	bDescriptorSubtype      1 (AS_GENERAL)
	bTerminalLink           1
	bDelay                  1 frames
	wFormatTag              1 PCM
      AudioStreaming Interface Descriptor:
	bLength                14
	bDescriptorType        36
	bDescriptorSubtype      2 (FORMAT_TYPE)
	bFormatType             1 (FORMAT_TYPE_I)
	bNrChannels             2
	bSubframeSize           3
	bBitResolution         24
	bSamFreqType            2 Discrete
	tSamFreq[ 0]        48000
	tSamFreq[ 1]        44100
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x01  EP 1 OUT
	bmAttributes            9
	  Transfer Type            Isochronous
	  Synch Type               Adaptive
	  Usage Type               Data
	wMaxPacketSize     0x0120  1x 288 bytes
	bInterval               1
	AudioControl Endpoint Descriptor:
	  bLength                 7
	  bDescriptorType        37
	  bDescriptorSubtype      1 (EP_GENERAL)
	  bmAttributes         0x01
	    Sampling Frequency
	  bLockDelayUnits         1 Milliseconds
	  wLockDelay              1 Milliseconds
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       3
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
	bLength                 7
	bDescriptorType        36
	bDescriptorSubtype      1 (AS_GENERAL)
	bTerminalLink           1
	bDelay                  1 frames
	wFormatTag              1 PCM
      AudioStreaming Interface Descriptor:
	bLength                11
	bDescriptorType        36
	bDescriptorSubtype      2 (FORMAT_TYPE)
	bFormatType             1 (FORMAT_TYPE_I)
	bNrChannels             2
	bSubframeSize           2
	bBitResolution         16
	bSamFreqType            1 Discrete
	tSamFreq[ 0]        96000
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x01  EP 1 OUT
	bmAttributes            9
	  Transfer Type            Isochronous
	  Synch Type               Adaptive
	  Usage Type               Data
	wMaxPacketSize     0x0180  1x 384 bytes
	bInterval               1
	AudioControl Endpoint Descriptor:
	  bLength                 7
	  bDescriptorType        37
	  bDescriptorSubtype      1 (EP_GENERAL)
	  bmAttributes         0x00
	  bLockDelayUnits         1 Milliseconds
	  wLockDelay              1 Milliseconds
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        1
      bAlternateSetting       4
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
	bLength                 7
	bDescriptorType        36
	bDescriptorSubtype      1 (AS_GENERAL)
	bTerminalLink           1
	bDelay                  1 frames
	wFormatTag              1 PCM
      AudioStreaming Interface Descriptor:
	bLength                11
	bDescriptorType        36
	bDescriptorSubtype      2 (FORMAT_TYPE)
	bFormatType             1 (FORMAT_TYPE_I)
	bNrChannels             2
	bSubframeSize           3
	bBitResolution         24
	bSamFreqType            1 Discrete
	tSamFreq[ 0]        96000
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x01  EP 1 OUT
	bmAttributes            9
	  Transfer Type            Isochronous
	  Synch Type               Adaptive
	  Usage Type               Data
	wMaxPacketSize     0x0240  1x 576 bytes
	bInterval               1
	AudioControl Endpoint Descriptor:
	  bLength                 7
	  bDescriptorType        37
	  bDescriptorSubtype      1 (EP_GENERAL)
	  bmAttributes         0x00
	  bLockDelayUnits         1 Milliseconds
	  wLockDelay              1 Milliseconds
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       0
      bNumEndpoints           0
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       1
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
	bLength                 7
	bDescriptorType        36
	bDescriptorSubtype      1 (AS_GENERAL)
	bTerminalLink           4
	bDelay                  1 frames
	wFormatTag              1 PCM
      AudioStreaming Interface Descriptor:
	bLength                14
	bDescriptorType        36
	bDescriptorSubtype      2 (FORMAT_TYPE)
	bFormatType             1 (FORMAT_TYPE_I)
	bNrChannels             2
	bSubframeSize           2
	bBitResolution         16
	bSamFreqType            2 Discrete
	tSamFreq[ 0]        48000
	tSamFreq[ 1]        44100
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x82  EP 2 IN
	bmAttributes            5
	  Transfer Type            Isochronous
	  Synch Type               Asynchronous
	  Usage Type               Data
	wMaxPacketSize     0x00c8  1x 200 bytes
	bInterval               1
	AudioControl Endpoint Descriptor:
	  bLength                 7
	  bDescriptorType        37
	  bDescriptorSubtype      1 (EP_GENERAL)
	  bmAttributes         0x01
	    Sampling Frequency
	  bLockDelayUnits         0 Undefined
	  wLockDelay              0 Undefined
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       2
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
	bLength                 7
	bDescriptorType        36
	bDescriptorSubtype      1 (AS_GENERAL)
	bTerminalLink           4
	bDelay                  1 frames
	wFormatTag              1 PCM
      AudioStreaming Interface Descriptor:
	bLength                14
	bDescriptorType        36
	bDescriptorSubtype      2 (FORMAT_TYPE)
	bFormatType             1 (FORMAT_TYPE_I)
	bNrChannels             2
	bSubframeSize           3
	bBitResolution         24
	bSamFreqType            2 Discrete
	tSamFreq[ 0]        48000
	tSamFreq[ 1]        44100
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x82  EP 2 IN
	bmAttributes            5
	  Transfer Type            Isochronous
	  Synch Type               Asynchronous
	  Usage Type               Data
	wMaxPacketSize     0x012c  1x 300 bytes
	bInterval               1
	AudioControl Endpoint Descriptor:
	  bLength                 7
	  bDescriptorType        37
	  bDescriptorSubtype      1 (EP_GENERAL)
	  bmAttributes         0x01
	    Sampling Frequency
	  bLockDelayUnits         0 Undefined
	  wLockDelay              0 Undefined
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       3
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
	bLength                 7
	bDescriptorType        36
	bDescriptorSubtype      1 (AS_GENERAL)
	bTerminalLink           4
	bDelay                  1 frames
	wFormatTag              1 PCM
      AudioStreaming Interface Descriptor:
	bLength                11
	bDescriptorType        36
	bDescriptorSubtype      2 (FORMAT_TYPE)
	bFormatType             1 (FORMAT_TYPE_I)
	bNrChannels             2
	bSubframeSize           2
	bBitResolution         16
	bSamFreqType            1 Discrete
	tSamFreq[ 0]        96000
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x82  EP 2 IN
	bmAttributes            5
	  Transfer Type            Isochronous
	  Synch Type               Asynchronous
	  Usage Type               Data
	wMaxPacketSize     0x0188  1x 392 bytes
	bInterval               1
	AudioControl Endpoint Descriptor:
	  bLength                 7
	  bDescriptorType        37
	  bDescriptorSubtype      1 (EP_GENERAL)
	  bmAttributes         0x00
	  bLockDelayUnits         0 Undefined
	  wLockDelay              0 Undefined
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        2
      bAlternateSetting       4
      bNumEndpoints           1
      bInterfaceClass         1 Audio
      bInterfaceSubClass      2 Streaming
      bInterfaceProtocol      0
      iInterface              0
      AudioStreaming Interface Descriptor:
	bLength                 7
	bDescriptorType        36
	bDescriptorSubtype      1 (AS_GENERAL)
	bTerminalLink           4
	bDelay                  1 frames
	wFormatTag              1 PCM
      AudioStreaming Interface Descriptor:
	bLength                11
	bDescriptorType        36
	bDescriptorSubtype      2 (FORMAT_TYPE)
	bFormatType             1 (FORMAT_TYPE_I)
	bNrChannels             2
	bSubframeSize           3
	bBitResolution         24
	bSamFreqType            1 Discrete
	tSamFreq[ 0]        96000
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x82  EP 2 IN
	bmAttributes            5
	  Transfer Type            Isochronous
	  Synch Type               Asynchronous
	  Usage Type               Data
	wMaxPacketSize     0x024c  1x 588 bytes
	bInterval               1
	AudioControl Endpoint Descriptor:
	  bLength                 7
	  bDescriptorType        37
	  bDescriptorSubtype      1 (EP_GENERAL)
	  bmAttributes         0x00
	  bLockDelayUnits         0 Undefined
	  wLockDelay              0 Undefined
    Interface Descriptor:
      bLength                 9
      bDescriptorType         4
      bInterfaceNumber        3
      bAlternateSetting       0
      bNumEndpoints           1
      bInterfaceClass         3 Human Interface Device
      bInterfaceSubClass      0 No Subclass
      bInterfaceProtocol      0 None
      iInterface              0
	HID Device Descriptor:
	  bLength                 9
	  bDescriptorType        33
	  bcdHID               1.00
	  bCountryCode            0 Not supported
	  bNumDescriptors         1
	  bDescriptorType        34 Report
	  wDescriptorLength      61
	 Report Descriptors:
	   ** UNAVAILABLE **
      Endpoint Descriptor:
	bLength                 7
	bDescriptorType         5
	bEndpointAddress     0x8f  EP 15 IN
	bmAttributes            3
	  Transfer Type            Interrupt
	  Synch Type               None
	  Usage Type               Data
	wMaxPacketSize     0x0010  1x 16 bytes
	bInterval              16
Device Status:     0x0002
  (Bus Powered)
  Remote Wakeup Enabled