Hi Dragan, On Tue, Nov 12, 2024 at 4:07 PM Dragan Simic <dsimic@xxxxxxxxxxx> wrote: > Please correct me if I'm wrong, but isn't this UART supposed to be > used for the Bluetooth part of an SDIO WiFi + Bluetooth module, in > form of a non-standard M.2 module that Radxa sells? UART8 is supposed to be used for any radio module connected to the M2E connector. It will typically be responsible for Bluetooth or BLE but it could be 802.15.4 or whatever. In any case, all wanting to use it will need the uart8 node enabled. > > With that in mind, I see very little sense in just enabling the UART, > without defining the entire Bluetooth interface, which AFAIK produces Defining a bluetooth node would hardwire idiosyncrasies of a given radio module's Bluetooth core. Sure you could add a sleep clock, all kind of sideband signals for wakeups, reset, power down, etc. But hey, some will use them, some won't. I think it's undesirable and unnecessary. You can hciattach from here and most will work just like that. Tighter integration or anything special, module specific on top should be handled individially, on a case-by-case basis. This is a dev board after all. I say trick of all trades. > nasty looking error messages in the kernel log when there's actually > nothing connected to the UART. My dmesg is clean as a whistle root@rock-3b:~# dmesg | grep -E 'fe6c0000|ttyS0' [ 0.344818] fe6c0000.serial: ttyS0 at MMIO 0xfe6c0000 (irq = 26, base_baud = 1500000) is a 16550A What kind of nasty errors do you recall? Kind regards, Tamas
