Bluetooth tty instance not showing up in /dev/tty*

[KDehm]

Hi,

I'm using a Wifi/BT module with CYW4343W chip on a custom board with STM32MP157.

When booting the system, the driver is loaded correctly and dmesg log shows

[ 1.089865] 4000e000.serial: ttySTM1 at MMIO 0x4000e000 (irq = 24, base_baud = 6250000) is a stm32-usart
[ 1.105124] stm32-usart 4000e000.serial: interrupt mode used for rx (no dma)
[ 1.112211] stm32-usart 4000e000.serial: interrupt mode used for tx (no dma)

which indicates, that the BT UART is allocated to ttySTM1. Bluetooth is working correctly as well.

Anyway, in the userspace I can't see the ttySTM1 instance under /dev/tty*

But driver is loaded and device is shown as serial0-0:

board:~# ls -l /sys/bus/serial/devices/serial0-0/
total 0
drwxr-xr-x 3 root root 0 Nov 15 10:46 bluetooth
lrwxrwxrwx 1 root root 0 Nov 15 11:00 driver -> ../../../../../../bus/serial/drivers/hci_uart_bcm
-r--r--r-- 1 root root 4096 Nov 15 11:00 modalias
lrwxrwxrwx 1 root root 0 Nov 15 11:00 of_node -> ../../../../../../firmware/devicetree/base/soc/serial@4000e000/bluetooth
drwxr-xr-x 2 root root 0 Nov 15 11:00 power
lrwxrwxrwx 1 root root 0 Nov 15 10:46 subsystem -> ../../../../../../bus/serial
-rw-r--r-- 1 root root 4096 Nov 15 10:46 uevent

The goal is to change the baudrate of the UART connection. The appropriate tools (btattach, patchram etc.) require the correct device path.

Can anyone help?

Thanks in advance,

Kai

[KDehm]

Addendum:

Here is the output of /proc/tty/

:~# cat /proc/tty/driver/stm32-usart
serinfo:1.0 driver revision:
0: uart:stm32-usart mmio:0x40010000 irq:25 tx:19716 rx:983 RTS|CTS|DTR|DSR|CD
1: uart:stm32-usart mmio:0x4000E000 irq:24 tx:32688 rx:2621 RTS|CTS|DTR|DSR|CD

ttySTM1 (0x4000e000) is listed here as well.