Dne 07. 05. 21 v 10:50 Jaroslav Kysela napsal(a): > Dne 07. 05. 21 v 10:37 Pavel Hofman napsal(a): >> Hi, >> >> The X-Fi USB HD device (and likely the similar 5.1 model too) can run at >> USB1.1 (with limited samplerates) and USB2 modes (with full specs). In >> linux the device stays at USB1.1. If connected to Windows with stock >> windows USB driver the same happens. However, when the Creative >> proprietary driver is installed, the device switches to USB2 and >> supports all features. When rebooting to linux without re-plugging, the >> USB2 mode stays and the device offers its USB2 configurations to >> snd-usb-audio. >> >> We captured USB packets in linux and Win7 with wireshark - both dumps >> are included. The windows dump shows that in windows as well as in linux >> the device starts as device 3.5.0 at USB1.1: >> >> DEVICE DESCRIPTOR >> bLength: 18 >> bDescriptorType: 0x01 (DEVICE) >> bcdUSB: 0x0110 >> bDeviceClass: Device (0x00) >> bDeviceSubClass: 0 >> bDeviceProtocol: 0 (Use class code info from Interface Descriptors) >> bMaxPacketSize0: 64 >> idVendor: Creative Technology, Ltd (0x041e) >> idProduct: Unknown (0x30d7) >> bcdDevice: 0x0100 >> iManufacturer: 1 >> iProduct: 2 >> iSerialNumber: 3 >> bNumConfigurations: 1 >> >> >> After USB1.1 enumeration, the windows host controlled by the vendor >> driver sends a request USR_FUNCTION_ABORT_PIPE to EP IN 6: >> >> >> The EP IN 6 descriptor (from USB1.1 configuration): >> >> ENDPOINT DESCRIPTOR >> bLength: 7 >> bDescriptorType: 0x05 (ENDPOINT) >> bEndpointAddress: 0x86 IN Endpoint:6 >> 1... .... = Direction: IN Endpoint >> .... 0110 = Endpoint Number: 0x6 >> bmAttributes: 0x03 >> .... ..11 = Transfertype: Interrupt-Transfer (0x3) >> wMaxPacketSize: 64 >> ...0 0... .... .... = Transactions per microframe: 1 (0) >> .... ..00 0100 0000 = Maximum Packet Size: 64 >> bInterval: 1 >> >> The request sent by the host is: >> USB URB >> [Source: host] >> [Destination: 3.5.6] >> USBPcap pseudoheader length: 27 >> IRP ID: 0xfffffa80073ee120 >> IRP USBD_STATUS: USBD_STATUS_SUCCESS (0x00000000) >> URB Function: URB_FUNCTION_ABORT_PIPE (0x0002) >> IRP information: 0x00, Direction: FDO -> PDO >> URB bus id: 3 >> Device address: 5 >> Endpoint: 0x86, Direction: IN >> URB transfer type: USB IRP Info (0xfe) >> Packet Data Length: 0 >> >> >> The device responds with a proprietary response, with a different source >> 3.5.127: >> USB URB >> [Source: 3.5.127] >> [Destination: host] >> USBPcap pseudoheader length: 27 >> IRP ID: 0xfffffa80073ee120 >> IRP USBD_STATUS: USBD_STATUS_SUCCESS (0x00000000) >> URB Function: URB_FUNCTION_ABORT_PIPE (0x0002) >> IRP information: 0x01, Direction: PDO -> FDO >> 0000 000. = Reserved: 0x00 >> .... ...1 = Direction: PDO -> FDO (0x1) >> URB bus id: 3 >> Device address: 5 >> Endpoint: 0xff, Direction: IN >> 1... .... = Direction: IN (1) >> .... 1111 = Endpoint number: 15 >> URB transfer type: Unknown (0xff) >> [Expert Info (Error/Malformed): USBPcap did not recognize URB >> Function code (report to desowin.org/USBPcap)] >> [USBPcap did not recognize URB Function code (report to >> desowin.org/USBPcap)] >> [Severity level: Error] >> [Group: Malformed] >> Packet Data Length: 0 >> >> >> Immediately after that the device re-connects as 3.6.0 and reports its >> USB2.0 description: >> >> DEVICE DESCRIPTOR >> bLength: 18 >> bDescriptorType: 0x01 (DEVICE) >> bcdUSB: 0x0200 >> bDeviceClass: Device (0x00) >> bDeviceSubClass: 0 >> bDeviceProtocol: 0 (Use class code info from Interface Descriptors) >> bMaxPacketSize0: 64 >> idVendor: Creative Technology, Ltd (0x041e) >> idProduct: Unknown (0x30d7) >> bcdDevice: 0x0100 >> iManufacturer: 1 >> iProduct: 2 >> iSerialNumber: 3 >> bNumConfigurations: 1 >> >> This is a regular USB-audio device which works OK in snd-usb-audio, as >> tested after rebooting from windows to linux. >> >> Please is there any similar case handled by the existing alsa usb driver >> which we could try to modify and test? My USB skills are not up to >> writing the required code myself from scratch, unfortunately. > > The switch can be probably implemented in the user space (libusb + udev > rules). There is something similar for modems (usb_modeswitch). > > Jaroslav Thank you for your useful suggestion. I am trying to send the command from userspace with pyusb. I can write/read from the given EP, but honestly, my knowledge of USB details is very poor. I found a discussion about MS Windows URB_FUNCTION_ABORT_PIPE which presumably is not available in linux kernel directly, but as usb_clear_halt() https://linux-usb-devel.narkive.com/jkl4OpsE/urb-function-abort-pipe . But here I am in user space. Please what should be the steps in emulating the above captured USB? Just some quazi-code would suffice, I will find a way to send it from userspace. Thank you very much for any help. Pavel.
