fix(usb): detect USB power mode to fallback to BLE #2458

Update `zmk_usb_get_conn_state` mapping to only treat `USB_DC_CONFIGURED` and `USB_DC_RESUME` as succesful HID connection. This is a naive solution for zmkfirmware#841, where having a USB-power cable without data driving the keyboard, like a power bank, still has the firmware thinking that it's connected to a host and futilely send data over USB. When the power cable is plugged in, the USB DC status (from Zephyr) goes through the following states: ``` USB_DC_CONNECTED -> USB_DC_SUSPEND ``` While for data cables: ``` USB_DC_CONNECTED -> USB_DC_SUSPEND -> USB_DC_RESUME -> USB_DC_RESET -> USB_DC_CONFIGURED ``` The enum mapping changes do allow the firmware to differentiate the 2 cases, but I'm unable to find any USB or USB HID specifications that explicitly states that the host machine will do the USB configuration step before the USB HID connection is considered complete. Just for safety sake, I added `USB_DC_RESUME` to be considered as successful too. Steps to reproduce original issue --------------------------------- 1. (Setup) Have ZMK keyboard with bluetooth profile enabled, set to prefer sending to USB 2. Power on keyboard via USB via power bank 3. Type, text should not show up anywhere ('consumed' by power bank) Testing ------ Built and flashed firmware with the commit changes, ran the same steps above, text showed up on expected device. Tested using 2 laptops (Ubuntu / Windows) using 2 different power banks. Logs (before) ----------------- ``` --- Started keyboard via battery [00:00:00.554,992] <inf> zmk: Welcome to ZMK! ... [00:00:01.133,514] <dbg> zmk: zmk_usb_get_conn_state: state: 11 --- Plugged power bank to keyboard [00:00:03.959,777] <inf> usb_hid: Device connected [00:00:03.959,808] <dbg> zmk: zmk_usb_get_conn_state: state: 2 [00:00:03.959,838] <dbg> zmk: zmk_usb_get_conn_state: state: 2 [00:00:03.959,869] <dbg> zmk: get_selected_transport: Only BLE is ready. [00:00:03.962,890] <inf> usb_hid: Device suspended [00:00:03.962,921] <dbg> zmk: zmk_usb_get_conn_state: state: 5 [00:00:03.962,951] <dbg> zmk: zmk_usb_get_conn_state: state: 5 [00:00:03.962,982] <dbg> zmk: get_selected_transport: Both endpoint transports are ready. Using 0 [00:00:03.962,982] <dbg> zmk: zmk_endpoints_send_report: usage page 0x07 [00:00:03.963,012] <dbg> zmk: zmk_endpoints_send_report: usage page 0x0C [00:00:03.963,073] <inf> zmk: Endpoint changed: USB ``` Logs with mapping changes (after) --------------------------------- ``` --- Started keyboard via battery [00:00:00.547,943] <inf> zmk: Welcome to ZMK! ... [00:00:00.549,804] <dbg> zmk: zmk_usb_get_conn_state: state: 11 ... --- Plugged power bank to keyboard [00:00:03.686,065] <inf> usb_hid: Device connected [00:00:03.686,126] <dbg> zmk: zmk_usb_get_conn_state: state: 2 [00:00:03.686,126] <dbg> zmk: zmk_usb_get_conn_state: state: 2 [00:00:03.686,157] <dbg> zmk: get_selected_transport: Only BLE is ready. [00:00:03.689,208] <inf> usb_hid: Device suspended [00:00:03.689,239] <dbg> zmk: zmk_usb_get_conn_state: state: 5 [00:00:03.689,270] <dbg> zmk: zmk_usb_get_conn_state: state: 5 [00:00:03.689,270] <dbg> zmk: get_selected_transport: Only BLE is ready. ``` Concerns -------- - This should work for USB Boot Protocol Support, but I have yet to test it. - TODO: Check what happens when keyboard that doesn't have bluetooth profiles has a power bank plugged into it - Above test isn't comprehensive. Maybe this can be a config option instead to catch unknown cases?

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fix(usb): detect USB power mode to fallback to BLE #2458

fix(usb): detect USB power mode to fallback to BLE #2458

Commits on Sep 14, 2024