Hi Daniel and linux-input@xxxxxxxxxxxxxxx, I've recently bought a 8bitdo usb adapter 2 - https://www.8bitdo.com/usb-wireless-adapter-2/ - and it didn't work with Linux in its Nintendo Switch Pro mode (emulating the Nintendo Pro Controller over the USB). It turned out that the following func sends 2 bytes in the JC_OUTPUT_USB_CMD, while the adapter expects 64 bytes. Maybe it expects fewer, but that's what the yuzu emulator sends to it over hidraw (bypassing the hid-nintendo), and it works. static int joycon_send_usb(struct joycon_ctlr *ctlr, u8 cmd, u32 timeout) { int ret; u8 buf[2] = {JC_OUTPUT_USB_CMD}; buf[1] = cmd; ctlr->usb_ack_match = cmd; ctlr->msg_type = JOYCON_MSG_TYPE_USB; ret = joycon_hid_send_sync(ctlr, buf, sizeof(buf), timeout); if (ret) hid_dbg(ctlr->hdev, "send usb command failed; ret=%d\n", ret); return ret; } If only 2 bytes are sent, then it causes the adapter to disconnect, probably due to some desync on the protocol level on the adapter side of things. [135278.921421] nintendo 0003:057E:2009.00DD: hidraw16: USB HID v81.11 Joystick [Nintendo Co., Ltd. Pro Controller] on usb-0000:07:00.3-3.1/input0 [135280.000469] nintendo 0003:057E:2009.00DD: failed reading SPI flash; ret=-71 [135280.000473] nintendo 0003:057E:2009.00DD: using factory cal for left stick [135280.008470] nintendo 0003:057E:2009.00DD: failed reading SPI flash; ret=-71 [135280.008473] nintendo 0003:057E:2009.00DD: using factory cal for right stick [135280.016469] nintendo 0003:057E:2009.00DD: failed reading SPI flash; ret=-71 [135280.016472] nintendo 0003:057E:2009.00DD: Failed to read left stick cal, using defaults; e=-71 [135280.024468] nintendo 0003:057E:2009.00DD: failed reading SPI flash; ret=-71 [135280.024471] nintendo 0003:057E:2009.00DD: Failed to read right stick cal, using defaults; e=-71 [135280.032470] nintendo 0003:057E:2009.00DD: failed reading SPI flash; ret=-71 [135280.032473] nintendo 0003:057E:2009.00DD: using factory cal for IMU [135280.040468] nintendo 0003:057E:2009.00DD: failed reading SPI flash; ret=-71 [135280.040471] nintendo 0003:057E:2009.00DD: Failed to read IMU cal, using defaults; ret=-71 [135280.040472] nintendo 0003:057E:2009.00DD: Unable to read IMU calibration data [135280.048470] nintendo 0003:057E:2009.00DD: Failed to set report mode; ret=-71 [135280.048743] nintendo 0003:057E:2009.00DD: probe - fail = -71 [135280.048749] nintendo: probe of 0003:057E:2009.00DD failed with error -71 [135280.050014] usb 3-3.1: USB disconnect, device number 53 In case it didn't create any problems with the actual Nintendo Pro Controller, nor with the JoyCons, could we change this code from u8 buf[2] = {JC_OUTPUT_USB_CMD}; to u8 buf[64] = {JC_OUTPUT_USB_CMD}; ? I know this change is a bit "out of the blue", but given that the protocol seems to be generally undocumented and reverse-engineered, maybe that's fine here. Thanks in advance. -- Robert Święcki
