RK平台,RK3399,RK3288,IO控制。

一，硬件IO复用配置

配置复用

GPIO3 :FF790~ FF788;

GPIO3_B7： GPIO

io -4 -r 0xff79e014

GPIO3 FF79e054

iomux

FF79e014

RK3399的iO控制

echo 227 > /sys/class/gpio/export

GPIO7A3: 7X32 +3 = 227

gpio0B5 : 0X32+13 = 13

gpio3_B7: 3X32 + 15 = 111

echo 111 > /sys/class/gpio/export

配置GRF

io -4 -r 0xff78800

[root@rk3399:/]# io -4 -r 0xff788000

ff788000: 00008000

[root@rk3399:/]#

GRF基地址为：FF77_0000

GRF_GPIO3B_IOMUX 0x0e014

io 0xff77e015 > 0x15

cat /sys/kernel/debug/gpio

GPIO控制

测试GPIO2_B2

写入GPIO2_B2位低电平

io -4 -w 0xff780000 0x7f0

红灯亮，设置生效

测试GPIO2_B3

写入GPIO2_B3为输出

io -4 -w 0xff780004 0x80ff1

GPIO2_B3输出为低

io -4 -w 0xff780000 0xff0

发现不生效，查询IOMUX寄存器

io -4 -r 0xff77e004

返回

0x00c0

查询寄存器文档可知bit7:6为11， gpio2_b3没有设为gpio

设置iomux为gpio

io -4 -w 0xff7e004 0x0000

设置无效，可能是被驱动限制了

测试GPIO2_B1

bit位为(B-A)*8 + 1 = 9

由前面可知，DDR应该已经是输出

直接设置DR

io -4 -w 0xff780000 0x5f0

二，另外一种用GPIO Debug接口控制的方法

以GPIO2_B2为例

查看GPIO2_B2的gpio number

rk3399:/sys/kernel/debug # cat gpio

GPIOs 0-31, platform/pinctrl, gpio0:

gpio-1 ( |vcc_sd ) out lo

gpio-4 ( |bt_default_wake_host) in lo

gpio-5 ( |power ) in hi

gpio-9 ( |bt_default_reset ) out lo

gpio-10 ( |reset ) out hi

GPIOs 32-63, platform/pinctrl, gpio1:

gpio-34 ( |int-n ) in hi

gpio-35 ( |camsys_gpio ) out hi

gpio-45 ( |enable ) out hi

gpio-46 ( |vsel ) out lo

gpio-49 ( |vsel ) out lo

gpio-54 ( |mpu6500 ) in lo

GPIOs 64-95, platform/pinctrl, gpio2:

gpio-64 ( |vbus-5v ) out lo

gpio-69 ( |power33 ) out hi

gpio-70 ( |power ) out hi

gpio-71 ( |reset ) out hi

gpio-72 ( |stanby ) out hi

gpio-73 ( |power18 ) out hi

gpio-74 ( |sysfs ) out lo

gpio-76 ( |int ) in hi

gpio-83 ( |bt_default_rts ) in hi

gpio-90 ( |bt_default_wake ) in lo

可知GPIO2_B2的number 为GPIO74

32*2 + 8+2

rk3399:/sys/class/gpio # echo 74 > export

1|rk3399:/sys/class/gpio # ls

export gpiochip0 gpiochip32 gpiochip96

gpio74 gpiochip128 gpiochip64 unexport

rk3399:/sys/class/gpio #

rk3399:/sys/class/gpio/gpio74 # ls

active_low device direction edge power subsystem uevent value

rk3399:/sys/class/gpio/gpio74 # echo 1 > value

rk3399:/sys/class/gpio/gpio74 # echo 0 > value

rk3399:/sys/class/gpio/gpio74 #