Hi, I saw the 8821cu chipset being merged for linus' next kernel release and decided to give it a try. I have been running 8821cu from https://github.com/morrownr/8821cu-20210118 succeffully, so I know my hardware works. The driver as merged in commit 07cef03b8d44dee7488de3d1585387e603c78676 to git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git can't find any firmware for the driver, and the card does not work. At boot it repeatedly logged failures to my kernel.log: 2022-12-16T19:20:21.563669+01:00 pinguin kernel: [ 7.823614] rtw_8821cu 2-11:1.0: Firmware version 24.11.0, H2C version 12 2022-12-16T19:20:21.563670+01:00 pinguin kernel: [ 7.906497] usbcore: registered new interface driver rtw_8821cu 2022-12-16T19:20:21.563670+01:00 pinguin kernel: [ 7.930657] rtw_8821cu 2-11:1.0 wlx1cbfcefeb2a3: renamed from wlan0 2022-12-16T19:20:59.576907+01:00 pinguin kernel: [ 631.847796] rtw_8821cu 2-11:1.0: failed to download firmware 2022-12-16T19:20:59.576910+01:00 pinguin kernel: [ 631.849195] rtw_8821cu 2-11:1.0: leave idle state failed 2022-12-16T19:20:59.580239+01:00 pinguin kernel: [ 631.851635] rtw_8821cu 2-11:1.0: failed to leave ips state 2022-12-16T19:20:59.580241+01:00 pinguin kernel: [ 631.851636] rtw_8821cu 2-11:1.0: failed to leave idle state 2022-12-16T19:21:08.563579+01:00 pinguin kernel: [ 640.833372] rtw_8821cu 2-11:1.0: error beacon valid 2022-12-16T19:21:08.563590+01:00 pinguin kernel: [ 640.833480] rtw_8821cu 2-11:1.0: failed to download rsvd page 2022-12-16T19:21:08.563591+01:00 pinguin kernel: [ 640.833640] rtw_8821cu 2-11:1.0: failed to download firmware 2022-12-16T19:21:08.563591+01:00 pinguin kernel: [ 640.835040] rtw_8821cu 2-11:1.0: leave idle state failed 2022-12-16T19:21:08.566911+01:00 pinguin kernel: [ 640.837510] rtw_8821cu 2-11:1.0: failed to leave ips state 2022-12-16T19:21:08.566915+01:00 pinguin kernel: [ 640.837513] rtw_8821cu 2-11:1.0: failed to leave idle state 2022-12-16T19:21:17.550263+01:00 pinguin kernel: [ 649.820641] rtw_8821cu 2-11:1.0: error beacon valid 2022-12-16T19:21:17.550288+01:00 pinguin kernel: [ 649.820759] rtw_8821cu 2-11:1.0: failed to download rsvd page There is no mention of what firmware would be needed in the source code itself, yet the repository https://github.com/ulli-kroll/rtl8821cu includes a file firmware/rtl8821cufw.bin. I don't know whether this needs another big update before linus merge window for 6.2 closes, so I chose to report it early. My hardware: * XVZ USB WiFi Dongle für PC 600Mbps Dual Band shows up as: Bus 002 Device 003: ID 0bda:c811 Realtek Semiconductor Corp. 802.11ac NIC Bus 002 Device 003: ID 0bda:c811 Realtek Semiconductor Corp. 802.11ac NIC Device Descriptor: bLength 18 bDescriptorType 1 bcdUSB 2.00 bDeviceClass 0 bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 idVendor 0x0bda Realtek Semiconductor Corp. idProduct 0xc811 bcdDevice 2.00 iManufacturer 1 Realtek iProduct 2 802.11ac NIC iSerial 3 123456 bNumConfigurations 1 Configuration Descriptor: bLength 9 bDescriptorType 2 wTotalLength 0x0035 bNumInterfaces 1 bConfigurationValue 1 iConfiguration 0 bmAttributes 0xa0 (Bus Powered) Remote Wakeup MaxPower 500mA Interface Descriptor: bLength 9 bDescriptorType 4 bInterfaceNumber 0 bAlternateSetting 0 bNumEndpoints 5 bInterfaceClass 255 Vendor Specific Class bInterfaceSubClass 255 Vendor Specific Subclass bInterfaceProtocol 255 Vendor Specific Protocol iInterface 2 802.11ac NIC Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x84 EP 4 IN bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x05 EP 5 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x06 EP 6 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x87 EP 7 IN bmAttributes 3 Transfer Type Interrupt Synch Type None Usage Type Data wMaxPacketSize 0x0040 1x 64 bytes bInterval 3 Endpoint Descriptor: bLength 7 bDescriptorType 5 bEndpointAddress 0x08 EP 8 OUT bmAttributes 2 Transfer Type Bulk Synch Type None Usage Type Data wMaxPacketSize 0x0200 1x 512 bytes bInterval 0 Device Qualifier (for other device speed): bLength 10 bDescriptorType 6 bcdUSB 2.00 bDeviceClass 0 bDeviceSubClass 0 bDeviceProtocol 0 bMaxPacketSize0 64 bNumConfigurations 1 Device Status: 0x0000 (Bus Powered) Ingo -- ╭─╮ Kennedy's Lemma: ╭│───╮ If you can parse Perl, you can solve the Halting Problem. │╰─│─╯ ╰──╯ http://www.perlmonks.org/?node_id=663393
