New ASUS Tinkerboard firmware "TinkerOS" supports more than 2 i2c buses

[gen2thomas]

All my Tinkerboards (3x Tinkerboard, 1x Tinkerboard S) run with armbian at the moment because the old TinkerOS was terrible at time of purchase. This days I have tried it again and was pleasantly surprised. On this occasion I have noticed 6 I2C busses:

linaro@tinkerboard:~$ sudo i2cdetect -l
i2c-0	i2c       	rk3x-i2c                        	I2C adapter
i2c-1	i2c       	rk3x-i2c                        	I2C adapter
i2c-2	i2c       	rk3x-i2c                        	I2C adapter
i2c-3	i2c       	rk3x-i2c                        	I2C adapter
i2c-4	i2c       	rk3x-i2c                        	I2C adapter
i2c-6	i2c       	DesignWare HDMI                 	I2C adapter

Two of them have connections on pinout: I2C1 (3, 5) and I2C4 (27, 28 marked blue). I have tested I2C4 and it runs fine. Unfortunately gobot supports only two or wrong I2C buses (/dev/i2c-0, /dev/i2c-1). Maybe we should avoid using other than I2C1 and I2C4?