Dne 13. 07. 21 v 14:05 Jerome Brunet napsal(a):
On Tue 13 Jul 2021 at 12:22, Pavel Hofman <pavel.hofman@xxxxxxxxxxx> wrote:
Hi,
I am testing the three Ruslan's async feedback patches as modified by
Jerome and I hit a regression in windows 10 enumeration.
Ruslan posted an already accepted patch
https://github.com/torvalds/linux/commit/789ea77310f0200c84002884ffd628e2baf3ad8a#diff-876615ece7fb56ce8d45fc70623bef9caa2548e810426f217fb785ffa10b33d5
which allowed win10 enumeration.
Ruslan's async feedback patchset kept the change:
https://patchwork.kernel.org/project/linux-usb/patch/1614603943-11668-5-git-send-email-ruslan.bilovol@xxxxxxxxx/
diff --git a/drivers/usb/gadget/function/f_uac2.c
b/drivers/usb/gadget/function/f_uac2.c
index 72b42f8..91b22fb 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -506,6 +506,10 @@ static int set_ep_max_packet_size(const struct
f_uac2_opts *uac2_opts,
max_size_bw = num_channels(chmask) * ssize *
((srate / (factor / (1 << (ep_desc->bInterval - 1)))) + 1);
+
+ if (!is_playback && (uac2_opts->c_sync == USB_ENDPOINT_SYNC_ASYNC))
+ max_size_bw = max_size_bw * FBACK_FREQ_MAX / 100;
+
ep_desc->wMaxPacketSize = cpu_to_le16(min_t(u16, max_size_bw,
max_size_ep));
Jerome's rebase patch which was accepted recently changed the functionality
to the original code:
https://patchwork.kernel.org/project/linux-usb/patch/20210603220104.1216001-4-jbrunet@xxxxxxxxxxxx/
diff --git a/drivers/usb/gadget/function/f_uac2.c
b/drivers/usb/gadget/function/f_uac2.c
index 321e6c05ba93..ae29ff2b2b68 100644
--- a/drivers/usb/gadget/function/f_uac2.c
+++ b/drivers/usb/gadget/function/f_uac2.c
@@ -584,8 +584,11 @@ static int set_ep_max_packet_size(const struct
f_uac2_opts *uac2_opts,
ssize = uac2_opts->c_ssize;
}
+ if (!is_playback && (uac2_opts->c_sync == USB_ENDPOINT_SYNC_ASYNC))
+ srate = srate * (1000 + uac2_opts->fb_max) / 1000;
+
max_size_bw = num_channels(chmask) * ssize *
- ((srate / (factor / (1 << (ep_desc->bInterval - 1)))) + 1);
+ DIV_ROUND_UP(srate, factor / (1 << (ep_desc->bInterval - 1)));
ep_desc->wMaxPacketSize = cpu_to_le16(min_t(u16, max_size_bw,
max_size_ep));
With this version my Win10 does not enumerate the USB AUDIO device, even if
it has only EP-IN capability (i.e. is_playback = true). For my setup the
EP-IN wMaxPacketSize is 192bytes vs. 196bytes in Ruslan's version, causing
win10 reporting "The specified range could not be found in the range list."
Maybe I am lacking USB expertize, but is there any reason why a 192bytes
maximum packet size should be considered invalid ? Just from your
comment, I can't figure it out.
It would help if you could detail the parameters you started your gadget
with (rate, format, channel number)
IIRC, Ruslan initial patchset reserved a fixed additional bandwidth
(around 20% I think) to deal with the explicit feedback.
The idea is that, 99.9% of the time, all you need is the ability to fit
one more sample in each packet. This is should be what the default
setting provides (up to 192kHz). If it does not do that, I made mistake.
The setting configurable because I was trying to avoid wasting USB
bandwith but still support poor quality platforms where 1 extra sample
is not enough (I think Ruslan mentioned having seen such system)
I am absolutely no USB expert. What I did was testing Jerome's patchset
and win10 refused to enumerate, even with the most trivial configuration
c_srate=p_srate=48000, 16bits, capture 2ch, playback 0ch which
configures no EP-OUT and no feedback EP-IN. To find the cause I went
back one patch (HEAD^) and win10 happily enumerated this no-EP-OUT
configuration. So I compared the usb config dump - see attached files
from Theosycon USB Descriptor Dumper - see the two attached files, named
after commit IDs.
The dumps differ in only one parameter EP-IN 1 wMaxPacketSize, for both
HS and the dumped "Other Speed Configuration Descriptor" i.e. FS:
diff 650f7f40dc1691a8ab4d1dc411f8f327b36e8d14.txt
cb1c270600b2c6f55f55f227775aaddf2cc78bed.txt
185c185
< 0x00C4 wMaxPacketSize (1 x 196 bytes)
---
> 0x00C0 wMaxPacketSize (1 x 192 bytes)
339c339
< 0x00C4 wMaxPacketSize (1 x 196 bytes)
---
> 0x00C0 wMaxPacketSize (1 x 192 bytes)
So I looked at the patch and saw the changed wMaxPacketSize calculation.
Adding +1 yielded what the original Ruslan's code yielded - one more
sample (i.e. 196 bytes instead of 192bytes). Therefore I put it in the
patch here. This value is accepted by win10.
I do not know how windows uac2 driver verifies validity of
wMaxPacketSize but clearly 196bytes (+1 sample) is accepted while
192bytes is refused. Linux does not care, just like Ruslan described in
his commit 789ea77310f020.
I checked duplex with EP-OUT enabled (i.e. with the feedback EP-IN), the
"new" calculation works OK in win10 (while the Jerome's values were
refused).
I really do not know the correct code for calculating the wMaxPacketSize
to satisfy the windows driver, but what I am posting works. I'll be
happy if someone knowledgeable fixes my layman quickfix.
Best regards,
Pavel.
Information for device Linux USB Audio Gadget (VID=0x1D6B PID=0x0101):
------------------------------
Connection Information:
------------------------------
Device current bus speed: HighSpeed
Device supports USB 1.1 specification
Device supports USB 2.0 specification
Device address: 0x0001
Current configuration value: 0x01
Number of open pipes: 0
------------------------------
Device Descriptor:
------------------------------
0x12 bLength
0x01 bDescriptorType
0x0200 bcdUSB
0xEF bDeviceClass (Miscellaneous device)
0x02 bDeviceSubClass
0x01 bDeviceProtocol
0x40 bMaxPacketSize0 (64 bytes)
0x1D6B idVendor
0x0101 idProduct
0x0513 bcdDevice
0x01 iManufacturer "Linux 5.13.1-v8+ with fe980000.usb"
0x02 iProduct "Linux USB Audio Gadget"
0x00 iSerialNumber
0x01 bNumConfigurations
Device Qualifier Descriptor:
------------------------------
0x0A bLength
0x06 bDescriptorType
0x0200 bcdUSB
0xEF bDeviceClass (Miscellaneous device)
0x02 bDeviceSubClass
0x01 bDeviceProtocol
0x40 bMaxPacketSize0 (64 bytes)
0x01 bNumConfigurations
0x00 bReserved
-------------------------
Configuration Descriptor:
-------------------------
0x09 bLength
0x02 bDescriptorType
0x007F wTotalLength (127 bytes)
0x02 bNumInterfaces
0x01 bConfigurationValue
0x00 iConfiguration
0xC0 bmAttributes (Self-powered Device)
0x01 bMaxPower (2 mA)
Interface Association Descriptor:
------------------------------
0x08 bLength
0x0B bDescriptorType
0x00 bFirstInterface
0x02 bInterfaceCount
0x01 bFunctionClass (Audio Device Class)
0x00 bFunctionSubClass
0x20 bFunctionProtocol (Audio Protocol IP version 2.00)
0x04 iFunction "Source/Sink"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x00 bInterfaceNumber
0x00 bAlternateSetting
0x00 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x01 bInterfaceSubClass (Audio Control Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x05 iInterface "Topology Control"
AC Interface Header Descriptor:
------------------------------
0x09 bLength
0x24 bDescriptorType
0x01 bDescriptorSubtype
0x0200 bcdADC
0x08 bCategory (IO_BOX)
0x002E wTotalLength (46 bytes)
0x00 bmControls
AC Clock Source Descriptor:
------------------------------
0x08 bLength
0x24 bDescriptorType
0x0A bDescriptorSubtype
0x03 bClockID
0x01 bmAttributes
0x01 bmControls
Clock Frequency Control - read only
0x00 bAssocTerminal
0x06 iClockSource "48000Hz"
AC Input Terminal Descriptor:
------------------------------
0x11 bLength
0x24 bDescriptorType
0x02 bDescriptorSubtype
0x01 bTerminalID
0x0200 wTerminalType (Input Undefined)
0x00 bAssocTerminal
0x03 bCSourceID
0x02 bNrChannels (2 channels)
0x00000003 bmChannelConfig
0x00 iChannelNames
0x03 bmControls
Copy Protect Control - host programmable
0x09 iTerminal "USBD Out"
AC Output Terminal Descriptor:
------------------------------
0x0C bLength
0x24 bDescriptorType
0x03 bDescriptorSubtype
0x02 bTerminalID
0x0101 wTerminalType (USB Streaming)
0x00 bAssocTerminal
0x01 bSourceID
0x03 bCSourceID
0x0003 bmControls
Copy Protect Control - host programmable
0x0A iTerminal "USBH In"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x01 bInterfaceNumber
0x00 bAlternateSetting
0x00 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x02 bInterfaceSubClass (Audio Streaming Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x0E iInterface "Capture Inactive"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x01 bInterfaceNumber
0x01 bAlternateSetting
0x01 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x02 bInterfaceSubClass (Audio Streaming Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x0F iInterface "Capture Active"
AS Interface Descriptor:
------------------------------
0x10 bLength
0x24 bDescriptorType
0x01 bDescriptorSubtype
0x02 bTerminalLink
0x00 bmControls
0x01 bFormatType (FORMAT_TYPE_1)
0x00000001 bmFormats
PCM
0x02 bNrChannels (2 channels)
0x00000003 bmChannelConfig
0x00 iChannelNames
AS Format Type 1 Descriptor:
------------------------------
0x06 bLength
0x24 bDescriptorType
0x02 bDescriptorSubtype
0x01 bFormatType (FORMAT_TYPE_1)
0x02 bSubslotSize
0x10 bBitResolution (16 bits per sample)
Endpoint Descriptor:
------------------------------
0x07 bLength
0x05 bDescriptorType
0x81 bEndpointAddress (IN endpoint 1)
0x05 bmAttributes (Transfer: Isochronous / Synch: Asynchronous / Usage: Data)
0x00C4 wMaxPacketSize (1 x 196 bytes)
0x04 bInterval (8 microframes)
AS Isochronous Data Endpoint Descriptor:
------------------------------
0x08 bLength
0x25 bDescriptorType
0x01 bDescriptorSubtype
0x00 bmAttributes
0x00 bmControls
0x00 bLockDelayUnits (undefined)
0x0000 wLockDelay
-------------------------------------
Other Speed Configuration Descriptor:
-------------------------------------
0x09 bLength
0x07 bDescriptorType
0x007F wTotalLength (127 bytes)
0x02 bNumInterfaces
0x01 bConfigurationValue
0x00 iConfiguration
0xC0 bmAttributes (Self-powered Device)
0x01 bMaxPower (2 mA)
Interface Association Descriptor:
------------------------------
0x08 bLength
0x0B bDescriptorType
0x00 bFirstInterface
0x02 bInterfaceCount
0x01 bFunctionClass (Audio Device Class)
0x00 bFunctionSubClass
0x20 bFunctionProtocol (Audio Protocol IP version 2.00)
0x04 iFunction "Source/Sink"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x00 bInterfaceNumber
0x00 bAlternateSetting
0x00 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x01 bInterfaceSubClass (Audio Control Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x05 iInterface "Topology Control"
AC Interface Header Descriptor:
------------------------------
0x09 bLength
0x24 bDescriptorType
0x01 bDescriptorSubtype
0x0200 bcdADC
0x08 bCategory (IO_BOX)
0x002E wTotalLength (46 bytes)
0x00 bmControls
AC Clock Source Descriptor:
------------------------------
0x08 bLength
0x24 bDescriptorType
0x0A bDescriptorSubtype
0x03 bClockID
0x01 bmAttributes
0x01 bmControls
Clock Frequency Control - read only
0x00 bAssocTerminal
0x06 iClockSource "48000Hz"
AC Input Terminal Descriptor:
------------------------------
0x11 bLength
0x24 bDescriptorType
0x02 bDescriptorSubtype
0x01 bTerminalID
0x0200 wTerminalType (Input Undefined)
0x00 bAssocTerminal
0x03 bCSourceID
0x02 bNrChannels (2 channels)
0x00000003 bmChannelConfig
0x00 iChannelNames
0x03 bmControls
Copy Protect Control - host programmable
0x09 iTerminal "USBD Out"
AC Output Terminal Descriptor:
------------------------------
0x0C bLength
0x24 bDescriptorType
0x03 bDescriptorSubtype
0x02 bTerminalID
0x0101 wTerminalType (USB Streaming)
0x00 bAssocTerminal
0x01 bSourceID
0x03 bCSourceID
0x0003 bmControls
Copy Protect Control - host programmable
0x0A iTerminal "USBH In"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x01 bInterfaceNumber
0x00 bAlternateSetting
0x00 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x02 bInterfaceSubClass (Audio Streaming Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x0E iInterface "Capture Inactive"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x01 bInterfaceNumber
0x01 bAlternateSetting
0x01 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x02 bInterfaceSubClass (Audio Streaming Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x0F iInterface "Capture Active"
AS Interface Descriptor:
------------------------------
0x10 bLength
0x24 bDescriptorType
0x01 bDescriptorSubtype
0x02 bTerminalLink
0x00 bmControls
0x01 bFormatType (FORMAT_TYPE_1)
0x00000001 bmFormats
PCM
0x02 bNrChannels (2 channels)
0x00000003 bmChannelConfig
0x00 iChannelNames
AS Format Type 1 Descriptor:
------------------------------
0x06 bLength
0x24 bDescriptorType
0x02 bDescriptorSubtype
0x01 bFormatType (FORMAT_TYPE_1)
0x02 bSubslotSize
0x10 bBitResolution (16 bits per sample)
Endpoint Descriptor:
------------------------------
0x07 bLength
0x05 bDescriptorType
0x81 bEndpointAddress (IN endpoint 1)
0x05 bmAttributes (Transfer: Isochronous / Synch: Asynchronous / Usage: Data)
0x00C4 wMaxPacketSize (1 x 196 bytes)
0x01 bInterval (1 frames)
AS Isochronous Data Endpoint Descriptor:
------------------------------
0x08 bLength
0x25 bDescriptorType
0x01 bDescriptorSubtype
0x00 bmAttributes
0x00 bmControls
0x00 bLockDelayUnits (undefined)
0x0000 wLockDelay
Microsoft OS Descriptor is not available. Error code: 0x0000001F
--------------------------------
String Descriptor Table
--------------------------------
Index LANGID String
0x00 0x0000 0x0409
0x01 0x0409 "Linux 5.13.1-v8+ with fe980000.usb"
0x02 0x0409 "Linux USB Audio Gadget"
0x04 0x0409 "Source/Sink"
0x05 0x0409 "Topology Control"
0x06 0x0409 "48000Hz"
0x09 0x0409 "USBD Out"
0x0A 0x0409 "USBH In"
0x0E 0x0409 "Capture Inactive"
0x0F 0x0409 "Capture Active"
------------------------------
Connection path for device:
Standard Enhanced PCI to USB Host Controller
Root Hub
Linux USB Audio Gadget (VID=0x1D6B PID=0x0101) Port: 1
Running on: Windows 10 or greater (Build Version 19041)
Brought to you by TDD v2.17.0, Feb 23 2021, 14:04:02
Information for device Linux USB Audio Gadget (VID=0x1D6B PID=0x0101):
------------------------------
Connection Information:
------------------------------
Device current bus speed: HighSpeed
Device supports USB 1.1 specification
Device supports USB 2.0 specification
Device address: 0x0001
Current configuration value: 0x01
Number of open pipes: 0
------------------------------
Device Descriptor:
------------------------------
0x12 bLength
0x01 bDescriptorType
0x0200 bcdUSB
0xEF bDeviceClass (Miscellaneous device)
0x02 bDeviceSubClass
0x01 bDeviceProtocol
0x40 bMaxPacketSize0 (64 bytes)
0x1D6B idVendor
0x0101 idProduct
0x0513 bcdDevice
0x01 iManufacturer "Linux 5.13.1-v8+ with fe980000.usb"
0x02 iProduct "Linux USB Audio Gadget"
0x00 iSerialNumber
0x01 bNumConfigurations
Device Qualifier Descriptor:
------------------------------
0x0A bLength
0x06 bDescriptorType
0x0200 bcdUSB
0xEF bDeviceClass (Miscellaneous device)
0x02 bDeviceSubClass
0x01 bDeviceProtocol
0x40 bMaxPacketSize0 (64 bytes)
0x01 bNumConfigurations
0x00 bReserved
-------------------------
Configuration Descriptor:
-------------------------
0x09 bLength
0x02 bDescriptorType
0x007F wTotalLength (127 bytes)
0x02 bNumInterfaces
0x01 bConfigurationValue
0x00 iConfiguration
0xC0 bmAttributes (Self-powered Device)
0x01 bMaxPower (2 mA)
Interface Association Descriptor:
------------------------------
0x08 bLength
0x0B bDescriptorType
0x00 bFirstInterface
0x02 bInterfaceCount
0x01 bFunctionClass (Audio Device Class)
0x00 bFunctionSubClass
0x20 bFunctionProtocol (Audio Protocol IP version 2.00)
0x04 iFunction "Source/Sink"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x00 bInterfaceNumber
0x00 bAlternateSetting
0x00 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x01 bInterfaceSubClass (Audio Control Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x05 iInterface "Topology Control"
AC Interface Header Descriptor:
------------------------------
0x09 bLength
0x24 bDescriptorType
0x01 bDescriptorSubtype
0x0200 bcdADC
0x08 bCategory (IO_BOX)
0x002E wTotalLength (46 bytes)
0x00 bmControls
AC Clock Source Descriptor:
------------------------------
0x08 bLength
0x24 bDescriptorType
0x0A bDescriptorSubtype
0x03 bClockID
0x01 bmAttributes
0x01 bmControls
Clock Frequency Control - read only
0x00 bAssocTerminal
0x06 iClockSource "48000Hz"
AC Input Terminal Descriptor:
------------------------------
0x11 bLength
0x24 bDescriptorType
0x02 bDescriptorSubtype
0x01 bTerminalID
0x0200 wTerminalType (Input Undefined)
0x00 bAssocTerminal
0x03 bCSourceID
0x02 bNrChannels (2 channels)
0x00000003 bmChannelConfig
0x00 iChannelNames
0x03 bmControls
Copy Protect Control - host programmable
0x09 iTerminal "USBD Out"
AC Output Terminal Descriptor:
------------------------------
0x0C bLength
0x24 bDescriptorType
0x03 bDescriptorSubtype
0x02 bTerminalID
0x0101 wTerminalType (USB Streaming)
0x00 bAssocTerminal
0x01 bSourceID
0x03 bCSourceID
0x0003 bmControls
Copy Protect Control - host programmable
0x0A iTerminal "USBH In"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x01 bInterfaceNumber
0x00 bAlternateSetting
0x00 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x02 bInterfaceSubClass (Audio Streaming Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x0E iInterface "Capture Inactive"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x01 bInterfaceNumber
0x01 bAlternateSetting
0x01 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x02 bInterfaceSubClass (Audio Streaming Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x0F iInterface "Capture Active"
AS Interface Descriptor:
------------------------------
0x10 bLength
0x24 bDescriptorType
0x01 bDescriptorSubtype
0x02 bTerminalLink
0x00 bmControls
0x01 bFormatType (FORMAT_TYPE_1)
0x00000001 bmFormats
PCM
0x02 bNrChannels (2 channels)
0x00000003 bmChannelConfig
0x00 iChannelNames
AS Format Type 1 Descriptor:
------------------------------
0x06 bLength
0x24 bDescriptorType
0x02 bDescriptorSubtype
0x01 bFormatType (FORMAT_TYPE_1)
0x02 bSubslotSize
0x10 bBitResolution (16 bits per sample)
Endpoint Descriptor:
------------------------------
0x07 bLength
0x05 bDescriptorType
0x81 bEndpointAddress (IN endpoint 1)
0x05 bmAttributes (Transfer: Isochronous / Synch: Asynchronous / Usage: Data)
0x00C0 wMaxPacketSize (1 x 192 bytes)
0x04 bInterval (8 microframes)
AS Isochronous Data Endpoint Descriptor:
------------------------------
0x08 bLength
0x25 bDescriptorType
0x01 bDescriptorSubtype
0x00 bmAttributes
0x00 bmControls
0x00 bLockDelayUnits (undefined)
0x0000 wLockDelay
-------------------------------------
Other Speed Configuration Descriptor:
-------------------------------------
0x09 bLength
0x07 bDescriptorType
0x007F wTotalLength (127 bytes)
0x02 bNumInterfaces
0x01 bConfigurationValue
0x00 iConfiguration
0xC0 bmAttributes (Self-powered Device)
0x01 bMaxPower (2 mA)
Interface Association Descriptor:
------------------------------
0x08 bLength
0x0B bDescriptorType
0x00 bFirstInterface
0x02 bInterfaceCount
0x01 bFunctionClass (Audio Device Class)
0x00 bFunctionSubClass
0x20 bFunctionProtocol (Audio Protocol IP version 2.00)
0x04 iFunction "Source/Sink"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x00 bInterfaceNumber
0x00 bAlternateSetting
0x00 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x01 bInterfaceSubClass (Audio Control Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x05 iInterface "Topology Control"
AC Interface Header Descriptor:
------------------------------
0x09 bLength
0x24 bDescriptorType
0x01 bDescriptorSubtype
0x0200 bcdADC
0x08 bCategory (IO_BOX)
0x002E wTotalLength (46 bytes)
0x00 bmControls
AC Clock Source Descriptor:
------------------------------
0x08 bLength
0x24 bDescriptorType
0x0A bDescriptorSubtype
0x03 bClockID
0x01 bmAttributes
0x01 bmControls
Clock Frequency Control - read only
0x00 bAssocTerminal
0x06 iClockSource "48000Hz"
AC Input Terminal Descriptor:
------------------------------
0x11 bLength
0x24 bDescriptorType
0x02 bDescriptorSubtype
0x01 bTerminalID
0x0200 wTerminalType (Input Undefined)
0x00 bAssocTerminal
0x03 bCSourceID
0x02 bNrChannels (2 channels)
0x00000003 bmChannelConfig
0x00 iChannelNames
0x03 bmControls
Copy Protect Control - host programmable
0x09 iTerminal "USBD Out"
AC Output Terminal Descriptor:
------------------------------
0x0C bLength
0x24 bDescriptorType
0x03 bDescriptorSubtype
0x02 bTerminalID
0x0101 wTerminalType (USB Streaming)
0x00 bAssocTerminal
0x01 bSourceID
0x03 bCSourceID
0x0003 bmControls
Copy Protect Control - host programmable
0x0A iTerminal "USBH In"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x01 bInterfaceNumber
0x00 bAlternateSetting
0x00 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x02 bInterfaceSubClass (Audio Streaming Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x0E iInterface "Capture Inactive"
Interface Descriptor:
------------------------------
0x09 bLength
0x04 bDescriptorType
0x01 bInterfaceNumber
0x01 bAlternateSetting
0x01 bNumEndPoints
0x01 bInterfaceClass (Audio Device Class)
0x02 bInterfaceSubClass (Audio Streaming Interface)
0x20 bInterfaceProtocol (Audio Protocol IP version 2.00)
0x0F iInterface "Capture Active"
AS Interface Descriptor:
------------------------------
0x10 bLength
0x24 bDescriptorType
0x01 bDescriptorSubtype
0x02 bTerminalLink
0x00 bmControls
0x01 bFormatType (FORMAT_TYPE_1)
0x00000001 bmFormats
PCM
0x02 bNrChannels (2 channels)
0x00000003 bmChannelConfig
0x00 iChannelNames
AS Format Type 1 Descriptor:
------------------------------
0x06 bLength
0x24 bDescriptorType
0x02 bDescriptorSubtype
0x01 bFormatType (FORMAT_TYPE_1)
0x02 bSubslotSize
0x10 bBitResolution (16 bits per sample)
Endpoint Descriptor:
------------------------------
0x07 bLength
0x05 bDescriptorType
0x81 bEndpointAddress (IN endpoint 1)
0x05 bmAttributes (Transfer: Isochronous / Synch: Asynchronous / Usage: Data)
0x00C0 wMaxPacketSize (1 x 192 bytes)
0x01 bInterval (1 frames)
AS Isochronous Data Endpoint Descriptor:
------------------------------
0x08 bLength
0x25 bDescriptorType
0x01 bDescriptorSubtype
0x00 bmAttributes
0x00 bmControls
0x00 bLockDelayUnits (undefined)
0x0000 wLockDelay
Microsoft OS Descriptor is not available. Error code: 0x0000001F
--------------------------------
String Descriptor Table
--------------------------------
Index LANGID String
0x00 0x0000 0x0409
0x01 0x0409 "Linux 5.13.1-v8+ with fe980000.usb"
0x02 0x0409 "Linux USB Audio Gadget"
0x04 0x0409 "Source/Sink"
0x05 0x0409 "Topology Control"
0x06 0x0409 "48000Hz"
0x09 0x0409 "USBD Out"
0x0A 0x0409 "USBH In"
0x0E 0x0409 "Capture Inactive"
0x0F 0x0409 "Capture Active"
------------------------------
Connection path for device:
Standard Enhanced PCI to USB Host Controller
Root Hub
Linux USB Audio Gadget (VID=0x1D6B PID=0x0101) Port: 1
Running on: Windows 10 or greater (Build Version 19041)
Brought to you by TDD v2.17.0, Feb 23 2021, 14:04:02
