Rock3/CM3p/e25/GPIO

     ROCK 3 >  ROCK 3 Compute Module Plus >  Radxa E25 >  GPIO

General purpose input-output (GPIO) connector

Radxa E25 has a 10-pin expansion header.

Pin#	Function1	Function2	Function3	Function4	Gpionumber
1	GPIO0_B4	CAN0_RX_M0	I2C1_SDA		12
2	GPIO3_C2	SPI1_MISO_M1	UART5_TX_M1	I2S1_SDO3_M2	114
3	GPIO3_C3	SPI1_CLK_M1	UART5_RX_M1	I2S1_SCLK_RX_M2	115
4	GPIO3_C0	PWM13_M0	UART3_RX_M1		112
5	GND
6	GPIO1_A1	CAN1_TX_M0	UART3_TX_M0	I2C3_SCL_M0	33
7	GPIO1_A0	CAN1_RX_M0	UART3_RX_M0	I2C3_SDA_M0	32
8	GPIO3_A1	SPI1_CS0_M1			97
9	GPIO3_C1	I2S1_SDO2_M2	SPI1_MOSI_M1		113
10	GPIO0_B3	CAN0_TX_M0	I2C1_SCL		11

Rockchip RK3568 GPIO has 5 banks, GPIO0 to GPIO4, each bank has 32pins, naming as below:

GPIO0_A0 ~ A7 
GPIO0_B0 ~ B7
GPIO0_C0 ~ C7
GPIO0_D0 ~ D7
   
GPIO1_A0 ~ A7
....
GPIO1_D0 ~ D7

For Rockchip 4.19 kernel, the GPIO number can be calculated as below, take GPIO3_C2 (PIN2 on 10-PIN HEADER) as an example:

GPIO3_C2 = 3*32 + 2*8 + 2 = 114 
(A=0, B=1, C=2, D=3)

To set GPIO3_C2 output

cd /sys/class/gpio
echo 114> export
cd gpio114
echo out > direction
echo 1 > value     # output high
echo 0 > value     # output low