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Unable to write on isochronous OUT
See original GitHub issueHi, I’ve been trying to run the code on tutorial docs but found no luck.
import usb.core
import usb.util
dev = usb.core.find(idVendor=0x2F9D, idProduct=0x3101)
reattach = False
if dev.is_kernel_driver_active(1):
reattach = True
dev.detach_kernel_driver(1)
if dev is None:
raise ValueError("Device not found")
cfg = dev.get_active_configuration()
print(cfg)
dev.write(0x2, [0])
if reattach:
dev.attach_kernel_driver(1)
outputs
2021-05-20 14:05:46,094 DEBUG:usb.backend.libusb1:_LibUSB.__init__(<CDLL 'libusb-1.0.so.0', handle 55eeac719720 at 0x7f0133210460>)
[timestamp] [threadID] facility level [function call] <message>
--------------------------------------------------------------------------------
[ 0.000012] [00027103] libusb: debug [libusb_init] created default context
[ 0.000021] [00027103] libusb: debug [libusb_init] libusb v1.0.24.11584
[ 0.000028] [00027103] libusb: debug [get_kernel_version] reported kernel version is 5.10.34-1-MANJARO
[ 0.000046] [00027103] libusb: debug [op_init] found usbfs at /dev/bus/usb
[ 0.000049] [00027103] libusb: debug [op_init] max iso packet length is (likely) 98304 bytes
[ 0.000055] [00027103] libusb: debug [op_init] sysfs is available
[ 0.000399] [0002715e] libusb: debug [linux_udev_event_thread_main] udev event thread entering
[ 0.004676] [00027103] libusb: debug [linux_get_device_address] getting address for device: usb1 detached: 0
[ 0.004700] [00027103] libusb: debug [linux_get_device_address] scan usb1
[ 0.004725] [00027103] libusb: debug [linux_get_device_address] bus=1 dev=1
[ 0.004729] [00027103] libusb: debug [linux_enumerate_device] busnum 1 devaddr 1 session_id 257
[ 0.004733] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 1/1 (session 257)
[ 0.004799] [00027103] libusb: debug [linux_get_device_address] getting address for device: 1-5 detached: 0
[ 0.004803] [00027103] libusb: debug [linux_get_device_address] scan 1-5
[ 0.004819] [00027103] libusb: debug [linux_get_device_address] bus=1 dev=6
[ 0.004822] [00027103] libusb: debug [linux_enumerate_device] busnum 1 devaddr 6 session_id 262
[ 0.004824] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 1/6 (session 262)
[ 0.004840] [00027103] libusb: debug [linux_get_parent_info] dev 0x55eeac73cdf0 (1-5) has parent 0x55eeac73c540 (usb1) port 5
[ 0.004891] [00027103] libusb: debug [linux_get_device_address] getting address for device: 1-6 detached: 0
[ 0.004895] [00027103] libusb: debug [linux_get_device_address] scan 1-6
[ 0.004909] [00027103] libusb: debug [linux_get_device_address] bus=1 dev=3
[ 0.004911] [00027103] libusb: debug [linux_enumerate_device] busnum 1 devaddr 3 session_id 259
[ 0.004914] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 1/3 (session 259)
[ 0.004930] [00027103] libusb: debug [linux_get_parent_info] dev 0x55eeac73caa0 (1-6) has parent 0x55eeac73c540 (usb1) port 6
[ 0.004978] [00027103] libusb: debug [linux_get_device_address] getting address for device: usb2 detached: 0
[ 0.004983] [00027103] libusb: debug [linux_get_device_address] scan usb2
[ 0.004997] [00027103] libusb: debug [linux_get_device_address] bus=2 dev=1
[ 0.005000] [00027103] libusb: debug [linux_enumerate_device] busnum 2 devaddr 1 session_id 513
[ 0.005002] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 2/1 (session 513)
[ 0.005062] [00027103] libusb: debug [linux_get_device_address] getting address for device: 2-2 detached: 0
[ 0.005066] [00027103] libusb: debug [linux_get_device_address] scan 2-2
[ 0.005081] [00027103] libusb: debug [linux_get_device_address] bus=2 dev=2
[ 0.005083] [00027103] libusb: debug [linux_enumerate_device] busnum 2 devaddr 2 session_id 514
[ 0.005086] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 2/2 (session 514)
[ 0.005106] [00027103] libusb: debug [linux_get_parent_info] dev 0x55eeac71f570 (2-2) has parent 0x55eeac73d0d0 (usb2) port 2
[ 0.005174] [00027103] libusb: debug [linux_get_device_address] getting address for device: usb3 detached: 0
[ 0.005182] [00027103] libusb: debug [linux_get_device_address] scan usb3
[ 0.005206] [00027103] libusb: debug [linux_get_device_address] bus=3 dev=1
[ 0.005210] [00027103] libusb: debug [linux_enumerate_device] busnum 3 devaddr 1 session_id 769
[ 0.005214] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 3/1 (session 769)
[ 0.005292] [00027103] libusb: debug [linux_get_device_address] getting address for device: 3-2 detached: 0
[ 0.005311] [00027103] libusb: debug [linux_get_device_address] scan 3-2
[ 0.005327] [00027103] libusb: debug [linux_get_device_address] bus=3 dev=2
[ 0.005330] [00027103] libusb: debug [linux_enumerate_device] busnum 3 devaddr 2 session_id 770
[ 0.005332] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 3/2 (session 770)
[ 0.005347] [00027103] libusb: debug [linux_get_parent_info] dev 0x55eeac71e7e0 (3-2) has parent 0x55eeac71f6a0 (usb3) port 2
[ 0.005398] [00027103] libusb: debug [linux_get_device_address] getting address for device: 3-3 detached: 0
[ 0.005402] [00027103] libusb: debug [linux_get_device_address] scan 3-3
[ 0.005417] [00027103] libusb: debug [linux_get_device_address] bus=3 dev=3
[ 0.005419] [00027103] libusb: debug [linux_enumerate_device] busnum 3 devaddr 3 session_id 771
[ 0.005422] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 3/3 (session 771)
[ 0.005436] [00027103] libusb: debug [linux_get_parent_info] dev 0x55eeac71ebc0 (3-3) has parent 0x55eeac71f6a0 (usb3) port 3
[ 0.005485] [00027103] libusb: debug [linux_get_device_address] getting address for device: usb4 detached: 0
[ 0.005490] [00027103] libusb: debug [linux_get_device_address] scan usb4
[ 0.005505] [00027103] libusb: debug [linux_get_device_address] bus=4 dev=1
[ 0.005507] [00027103] libusb: debug [linux_enumerate_device] busnum 4 devaddr 1 session_id 1025
[ 0.005510] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 4/1 (session 1025)
[ 0.005566] [00027103] libusb: debug [linux_get_device_address] getting address for device: usb5 detached: 0
[ 0.005571] [00027103] libusb: debug [linux_get_device_address] scan usb5
[ 0.005585] [00027103] libusb: debug [linux_get_device_address] bus=5 dev=1
[ 0.005587] [00027103] libusb: debug [linux_enumerate_device] busnum 5 devaddr 1 session_id 1281
[ 0.005590] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 5/1 (session 1281)
[ 0.005646] [00027103] libusb: debug [linux_get_device_address] getting address for device: usb6 detached: 0
[ 0.005650] [00027103] libusb: debug [linux_get_device_address] scan usb6
[ 0.005664] [00027103] libusb: debug [linux_get_device_address] bus=6 dev=1
[ 0.005667] [00027103] libusb: debug [linux_enumerate_device] busnum 6 devaddr 1 session_id 1537
[ 0.005669] [00027103] libusb: debug [linux_enumerate_device] allocating new device for 6/1 (session 1537)
[ 0.005750] [00027103] libusb: debug [usbi_add_event_source] add fd 5 events 1
[ 0.005755] [00027103] libusb: debug [usbi_io_init] using timer for timeouts
[ 0.005757] [00027103] libusb: debug [usbi_add_event_source] add fd 6 events 1
2021-05-20 14:05:46,100 INFO:usb.core:find(): using backend "usb.backend.libusb1"
2021-05-20 14:05:46,100 DEBUG:usb.backend.libusb1:_LibUSB.enumerate_devices()
[ 0.006111] [00027103] libusb: debug [libusb_get_device_list]
[ 0.006123] [00027103] libusb: debug [discovered_devs_append] need to increase capacity
2021-05-20 14:05:46,100 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fbbfd0>)
[ 0.006278] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,100 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd01c0>)
[ 0.006485] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,100 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fbbfd0>)
[ 0.006623] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,100 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0220>)
[ 0.006718] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,100 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fbbfd0>)
[ 0.006811] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0280>)
[ 0.006910] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fbbfd0>)
[ 0.007001] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd01f0>)
[ 0.007087] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fbbfd0>)
[ 0.007175] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_device_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>)
[ 0.007261] [00027103] libusb: debug [libusb_get_device_descriptor]
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.open_device(<usb.backend.libusb1._Device object at 0x7f0132fd0250>)
[ 0.007378] [00027103] libusb: debug [libusb_open] open 1.6
[ 0.007403] [00027103] libusb: debug [usbi_add_event_source] add fd 7 events 4
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.is_kernel_driver_active(<usb.backend.libusb1._DeviceHandle object at 0x7f0133335fa0>, 1)
[ 0.007457] [00027103] libusb: debug [libusb_kernel_driver_active] interface 1
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration(<usb.backend.libusb1._DeviceHandle object at 0x7f0133335fa0>)
[ 0.007518] [00027103] libusb: debug [libusb_get_configuration]
[ 0.007545] [00027103] libusb: debug [libusb_get_configuration] active config 1
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.007615] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.007622] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.007624] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0, 0, 0)
2021-05-20 14:05:46,101 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.007800] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.007805] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.007808] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0, 1, 0)
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.007961] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.007966] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.007969] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 1, 0, 0)
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.008080] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.008085] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.008088] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 1, 1, 0)
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.008217] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.008222] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.008232] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_endpoint_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0, 1, 1, 0)
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 1, 1, 0)
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.008407] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.008412] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.008415] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 1, 2, 0)
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.008558] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.008563] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.008566] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 2, 0, 0)
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.008674] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.008679] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.008681] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 2, 1, 0)
2021-05-20 14:05:46,102 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.008810] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.008814] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.008817] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_endpoint_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0, 2, 1, 0)
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 2, 1, 0)
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.008983] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.008988] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.008990] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 2, 2, 0)
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.009123] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.009128] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.009131] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 3, 0, 0)
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.009238] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.009242] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.009245] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_endpoint_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0, 3, 0, 0)
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 3, 0, 0)
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.009417] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.009422] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.009425] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 3, 1, 0)
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.009558] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.009563] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.009565] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.009653] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.009658] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.009660] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0, 0, 0)
2021-05-20 14:05:46,103 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.009776] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.009781] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.009783] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0, 1, 0)
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.009909] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.009914] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.009917] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 1, 0, 0)
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.010025] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.010029] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.010032] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 1, 1, 0)
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.010154] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.010159] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.010161] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_endpoint_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0, 1, 1, 0)
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_interface_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 1, 1, 0)
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.get_configuration_descriptor(<usb.backend.libusb1._Device object at 0x7f0132fd0250>, 0)
[ 0.010329] [00027103] libusb: debug [libusb_get_config_descriptor] index 0
[ 0.010334] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.010336] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.claim_interface(<usb.backend.libusb1._DeviceHandle object at 0x7f0133335fa0>, 1)
[ 0.010431] [00027103] libusb: debug [libusb_claim_interface] interface 1
2021-05-20 14:05:46,104 DEBUG:usb.backend.libusb1:_LibUSB.iso_write(<usb.backend.libusb1._DeviceHandle object at 0x7f0133335fa0>, 2, 1, array('B', [0]), 1000)
[ 0.010572] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.010577] [00027103] libusb: debug [parse_endpoint] skipping descriptor 0x25
[ 0.010588] [00027103] libusb: debug [libusb_alloc_transfer] transfer 0x55eeac6b7098
[ 0.010801] [00027103] libusb: debug [libusb_submit_transfer] transfer 0x55eeac6b7098
[ 0.010809] [00027103] libusb: debug [add_to_flying_list] arm timer for timeout in 1000ms (first in line)
[ 0.010815] [00027103] libusb: debug [submit_iso_transfer] need 1 urbs for new transfer with length 1
[ 0.010819] [00027103] libusb: error [submit_iso_transfer] submiturb failed, errno=2
[ 0.010822] [00027103] libusb: debug [submit_iso_transfer] first URB failed, easy peasy
[ 0.010824] [00027103] libusb: debug [arm_timer_for_next_timeout] no timeouts, disarming timer
CONFIGURATION 1: 100 mA ==================================
bLength : 0x9 (9 bytes)
bDescriptorType : 0x2 Configuration
wTotalLength : 0xdd (221 bytes)
bNumInterfaces : 0x4
bConfigurationValue : 0x1
iConfiguration : 0x0
bmAttributes : 0xc0 Self Powered
bMaxPower : 0x32 (100 mA)
INTERFACE 0: Audio =====================================
bLength : 0x9 (9 bytes)
bDescriptorType : 0x4 Interface
bInterfaceNumber : 0x0
bAlternateSetting : 0x0
bNumEndpoints : 0x0
bInterfaceClass : 0x1 Audio
bInterfaceSubClass : 0x1
bInterfaceProtocol : 0x0
iInterface : 0x0
INTERFACE 1: Audio =====================================
bLength : 0x9 (9 bytes)
bDescriptorType : 0x4 Interface
bInterfaceNumber : 0x1
bAlternateSetting : 0x0
bNumEndpoints : 0x0
bInterfaceClass : 0x1 Audio
bInterfaceSubClass : 0x2
bInterfaceProtocol : 0x0
iInterface : 0x0
INTERFACE 1, 1: Audio ==================================
bLength : 0x9 (9 bytes)
bDescriptorType : 0x4 Interface
bInterfaceNumber : 0x1
bAlternateSetting : 0x1
bNumEndpoints : 0x1
bInterfaceClass : 0x1 Audio
bInterfaceSubClass : 0x2
bInterfaceProtocol : 0x0
iInterface : 0x0
ENDPOINT 0x2: Isochronous OUT ========================
bLength : 0x7 (7 bytes)
bDescriptorType : 0x5 Endpoint
bEndpointAddress : 0x2 OUT
bmAttributes : 0xd Isochronous
wMaxPacketSize : 0xc0 (192 bytes)
bInterval : 0x4
INTERFACE 2: Audio =====================================
bLength : 0x9 (9 bytes)
bDescriptorType : 0x4 Interface
bInterfaceNumber : 0x2
bAlternateSetting : 0x0
bNumEndpoints : 0x0
bInterfaceClass : 0x1 Audio
bInterfaceSubClass : 0x2
bInterfaceProtocol : 0x0
iInterface : 0x0
INTERFACE 2, 1: Audio ==================================
bLength : 0x9 (9 bytes)
bDescriptorType : 0x4 Interface
bInterfaceNumber : 0x2
bAlternateSetting : 0x1
bNumEndpoints : 0x1
bInterfaceClass : 0x1 Audio
bInterfaceSubClass : 0x2
bInterfaceProtocol : 0x0
iInterface : 0x0
ENDPOINT 0x81: Isochronous IN ========================
bLength : 0x7 (7 bytes)
bDescriptorType : 0x5 Endpoint
bEndpointAddress : 0x81 IN
bmAttributes : 0x5 Isochronous
wMaxPacketSize : 0xc0 (192 bytes)
bInterval : 0x4
INTERFACE 3: Human Interface Device ====================
bLength : 0x9 (9 bytes)
bDescriptorType : 0x4 Interface
bInterfaceNumber : 0x3
bAlternateSetting : 0x0
bNumEndpoints : 0x1
bInterfaceClass : 0x3 Human Interface Device
bInterfaceSubClass : 0x0
bInterfaceProtocol : 0x0
iInterface : 0x0
ENDPOINT 0x82: Interrupt IN ==========================
bLength : 0x7 (7 bytes)
bDescriptorType : 0x5 Endpoint
bEndpointAddress : 0x82 IN
bmAttributes : 0x3 Interrupt
wMaxPacketSize : 0x40 (64 bytes)
bInterval : 0x4
Traceback (most recent call last):
File "/home/xinbg/Documents/pyusb/main.py", line 15, in <module>
dev.write(0x2, [0])
File "/usr/lib/python3.9/site-packages/usb/core.py", line 979, in write
return fn(
File "/usr/lib/python3.9/site-packages/usb/_debug.py", line 62, in do_trace
return f(*args, **named_args)
File "/usr/lib/python3.9/site-packages/usb/backend/libusb1.py", line 874, in iso_write
return handler.submit(self.ctx)
File "/usr/lib/python3.9/site-packages/usb/backend/libusb1.py", line 680, in submit
_check(_lib.libusb_submit_transfer(self.transfer))
File "/usr/lib/python3.9/site-packages/usb/backend/libusb1.py", line 604, in _check
raise USBError(_strerror(ret), ret, _libusb_errno[ret])
usb.core.USBError: [Errno 5] Input/Output Error
[ 0.011766] [00027103] libusb: debug [libusb_free_transfer] transfer 0x55eeac6b7098
2021-05-20 14:05:46,106 DEBUG:usb.backend.libusb1:_LibUSB.release_interface(<usb.backend.libusb1._DeviceHandle object at 0x7f0133335fa0>, 1)
[ 0.011869] [00027103] libusb: debug [libusb_release_interface] interface 1
2021-05-20 14:05:46,106 DEBUG:usb.backend.libusb1:_LibUSB.close_device(<usb.backend.libusb1._DeviceHandle object at 0x7f0133335fa0>)
[ 0.011936] [00027103] libusb: debug [libusb_close]
[ 0.011941] [00027103] libusb: debug [usbi_remove_event_source] remove fd 7
2021-05-20 14:05:46,106 DEBUG:usb.backend.libusb1:_LibUSB._finalize_object()
[ 0.012002] [00027103] libusb: debug [libusb_exit]
[ 0.012006] [00027103] libusb: debug [libusb_exit] destroying default context
[ 0.012009] [00027103] libusb: debug [libusb_handle_events_timeout_completed] doing our own event handling
[ 0.012011] [00027103] libusb: debug [handle_events] event sources modified, reallocating event data
[ 0.012015] [00027103] libusb: debug [usbi_wait_for_events] poll() 2 fds with timeout in 0ms
[ 0.012020] [00027103] libusb: debug [usbi_wait_for_events] poll() returned 0
[ 0.012022] [00027103] libusb: debug [libusb_unref_device] destroy device 6.1
[ 0.012025] [00027103] libusb: debug [libusb_unref_device] destroy device 5.1
[ 0.012028] [00027103] libusb: debug [libusb_unref_device] destroy device 4.1
[ 0.012030] [00027103] libusb: debug [libusb_unref_device] destroy device 3.3
[ 0.012032] [00027103] libusb: debug [libusb_unref_device] destroy device 3.2
[ 0.012035] [00027103] libusb: debug [libusb_unref_device] destroy device 3.1
[ 0.012037] [00027103] libusb: debug [libusb_unref_device] destroy device 2.2
[ 0.012039] [00027103] libusb: debug [libusb_unref_device] destroy device 2.1
[ 0.012042] [00027103] libusb: debug [libusb_unref_device] destroy device 1.3
[ 0.012044] [00027103] libusb: debug [libusb_unref_device] destroy device 1.6
[ 0.012046] [00027103] libusb: debug [libusb_unref_device] destroy device 1.1
[ 0.012049] [00027103] libusb: debug [usbi_remove_event_source] remove fd 6
[ 0.012055] [00027103] libusb: debug [usbi_remove_event_source] remove fd 5
[ 0.012074] [0002715e] libusb: debug [linux_udev_event_thread_main] udev event thread exiting
The problem seems to be something wrong with submitting the transfer.
[ 0.009953] [00026f4e] libusb: error [submit_iso_transfer] submiturb failed, errno=2
[ 0.009955] [00026f4e] libusb: debug [submit_iso_transfer] first URB failed, easy peasy
I search through libusb’s docs, but there is no errno=2 found, only negative error numbers. I’m confused here, can someone help?
Issue Analytics
- State:
- Created 2 years ago
- Comments:11 (8 by maintainers)
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Good progress.
I recommend you to read the basic of USB here. https://www.usbmadesimple.co.uk/
And read pyusb tutorial in more detail about dev.set_interface_altsetting(). https://github.com/pyusb/pyusb/blob/master/docs/tutorial.rst