BPI-R2-GPIO

2nd function	main function	pin#	xxxxxxxxxxxxxxxxxxxxx	pin#	main function	2nd function
	+3V3	1		2	+5V
GPIO 56 #	I2C1_SDA	3		4	+5V
GPIO 55 #	I2C1_SCL	5		6	GND
GPIO101	PWM 7	7		8	UART0-TX	GPIO 59 #
	GND	9		10	UART0-RX	GPIO 60 #
GPIO 51 #	PWM1 / UART1-TX	11		12
GPIO 52 #	PWM2 / UART1-RX	13		14	GND
GPIO 98 #		15		16		GPIO 61 #
	+3V3	17		18		GPIO 62 #
GPIO 68 #	PWM5 / SPI1 MOSI	19		20	GND
GPIO 69	PWM6 / SPI1 MISO	21		22	SPI0 CLK	GPIO 63
GPIO 67	PWM4 / SPI1 CLK	23		24	SPI1 CS	GPIO 70
	GND	25		26	SPI0 CS	GPIO 66
GPIO 58	I2C2 SDA	27		28	I2C2 SCL	GPIO 57
GPIO 85		29		30	GND
GPIO 82	SPI0 MOSI	31		32	SPI0 MOSI	GPIO 64
		33		34	GND
		35		36	SPI0 MISO	GPIO 65
GPIO 86		37		38	I2S IN
	GND	39		40	I2S OUT

(# verified gpio working, 101 is blocked by pwm)

• uart0 (dts) ⇒ Debug-Uart
• uart1 (dts) ⇒ undefined ⇒ mt7622_uart2_2_tx_rx_pins (59/60)
• uart2 (dts) ⇒ uart1 (gpio) ⇒ mt7622_uart2_1_tx_rx_pins (51/52)

root@bpi-iot-ros-ai:~# cat /sys/kernel/debug/pinctrl/10211000.pinctrl-pinctrl_mt7622/gpio-ranges
GPIO ranges handled:
0: pinctrl_mt7622 GPIOS [409 - 511] PINS [0 - 102]
root@bpi-iot-ros-ai:~# GPIO_NO=$((409+56))
root@bpi-iot-ros-ai:~# echo $GPIO_NO
465
root@bpi-iot-ros-ai:~# echo $GPIO_NO > /sys/class/gpio/export

-bash: echo: write error: Invalid argument => blocked by i2c1

#if i2c1 is disabled in dts:
root@bpi-r64:~# echo $GPIO_NO > /sys/class/gpio/export                          
root@bpi-r64:~# echo out > /sys/class/gpio/gpio${GPIO_NO}/direction             
root@bpi-r64:~# echo 1 > /sys/class/gpio/gpio${GPIO_NO}/value #led goes on
root@bpi-r64:~# echo 0 > /sys/class/gpio/gpio${GPIO_NO}/value #led goes off

The sysfs interface (/sys/class/gpio/…) needs kernel-option CONFIG_GPIO_SYSFS

debug-Uart is uart0 in DTS, uart2 seems to be uart1 of gpio header…uart1 is currently not defined in dts.

needs LEDS_GPIO [=y]

there is only red and green, red seems not working

  echo 1 > /sys/class/leds/bpi-r64\:pio\:green/brightness

in linux numbering begins at 0 where on bpi documentation/gpio-header pwms starting at 1…

• pwm1 pin 11 (GPIO 51)
• pwm2 pin 13 (GPIO 52)
• pwm3 fan,inverted - seems not working correctly
• pwm4 pin 23 (GPIO 67)
• pwm5 pin 19 (GPIO 68)
• pwm6 pin 21 (GPIO 69)
• pwm7 pin7 (GPIO101) - seems not working

pwm working except 3 (2) and 7 (6) in my 5.7-pwm branch

root@bpi-r64:~# cd /sys/class/pwm/pwmchip0
root@bpi-r64:/sys/class/pwm/pwmchip0# echo 0 > export
root@bpi-r64:/sys/class/pwm/pwmchip0# cd pwm0
root@bpi-r64:/sys/class/pwm/pwmchip0/pwm0# echo 10000 > period
root@bpi-r64:/sys/class/pwm/pwmchip0/pwm0# echo 5000 > duty_cycle
root@bpi-r64:/sys/class/pwm/pwmchip0/pwm0# echo 1 > enable

pwm-patches from sam are merged in 2020-07, but to use them there is cmd_pwm needed

http://forum.banana-pi.org/t/bpi-r64-current-u-boot-support/10077/74

both Available in 2020-04-bpi-pwm branch

here pwm1 (0) is defined in dts