GPIO
GPIO常用配置一般是配成LED输出或者key输入，下面是对设备树这部分修改的示例，供参考修改
注意：任何IO都只能配置一种功能，如果要修改已经有使用的IO需要找到对应位置注释掉原本的使用
LED配置
例如：将K1拓展引脚上的GPIO1_D4配置成LED，可以参考下面的修改
--- a/kernel/arch/arm64/boot/dts/rockchip/rk3568-kickpi-extend-40pin.dtsi
+++ b/kernel/arch/arm64/boot/dts/rockchip/rk3568-kickpi-extend-40pin.dtsi
@@ -29,10 +29,10 @@ gpio1d0 {
gpios = <&gpio1 RK_PD0 GPIO_ACTIVE_HIGH>;
default-state = "off";
};
+ gpio1d4 {
+ gpios = <&gpio1 RK_PD4 GPIO_ACTIVE_HIGH>;
+ default-state = "off";
+ };
gpio3b5 {
gpios = <&gpio3 RK_PB5 GPIO_ACTIVE_HIGH>;
default-state = "off";
测试
查看GPIO注册列表
$ ls /sys/class/leds/
gpio1b0/ gpio1b2/ gpio1d4/ gpio3b6/
gpio1a4/ gpio1b1/ gpio1d0/ gpio3b5/ gpio4c4/命令行控制GPIO
$ echo 1 > /sys/class/leds/gpio1d4/brightness
$ echo 0 > /sys/class/leds/gpio1d4/brightnessgpio-key配置
例如：将K1拓展引脚上的GPIO1_D4配置成KEY_1，可以参考下面的修改
--- a/kernel/arch/arm64/boot/dts/rockchip/rk3568-kickpi-extend-40pin.dtsi
+++ b/kernel/arch/arm64/boot/dts/rockchip/rk3568-kickpi-extend-40pin.dtsi
@@ -29,10 +29,10 @@ gpio1d0 {
gpios = <&gpio1 RK_PD0 GPIO_ACTIVE_HIGH>;
default-state = "off";
};
- gpio1d4 {
- gpios = <&gpio1 RK_PD4 GPIO_ACTIVE_HIGH>;
- default-state = "off";
- };
+ // gpio1d4 {
+ // gpios = <&gpio1 RK_PD4 GPIO_ACTIVE_HIGH>;
+ // default-state = "off";
+ // };
gpio3b5 {
gpios = <&gpio3 RK_PB5 GPIO_ACTIVE_HIGH>;
default-state = "off";
--- a/kernel/arch/arm64/boot/dts/rockchip/rk3568-kickpi-k1.dtsi
+++ b/kernel/arch/arm64/boot/dts/rockchip/rk3568-kickpi-k1.dtsi
@@ -76,6 +76,21 @@ fan0: gpio-fan {
status = "okay";
};
*/
+
+
+ gpio-keys {
+ compatible = "gpio-keys";
+ autorepeat;
+ status = "okay";
+
+ key_1D4 {
+ label = "GPIO_KEY_1D4";
+ linux,code = <KEY_1>;
+ gpios = <&gpio1 RK_PD4 GPIO_ACTIVE_LOW>;
+ debounce-interval = <100>;
+ };
+ };
+
};
&leds {
(END)其中code值可以参考驱动中的宏定义
rk356x-linux\kernel\include\uapi\linux\input-event-codes.h测试
Android测试使用命令getevent:
console:/ # getevent
add device 1: /dev/input/event3
name: "sunxi-ir-uinput"
add device 2: /dev/input/event2
name: "gt9xxnew_ts"
add device 3: /dev/input/event0
name: "sunxi-ir"
add device 4: /dev/input/event1
name: "gpio-keys"
/dev/input/event2: 0001 014a 00000001
/dev/input/event2: 0003 0035 00000247
/dev/input/event2: 0003 0036 000001c3
/dev/input/event2: 0003 0030 0000001e
/dev/input/event2: 0003 0032 0000001eLinux测试使用evtest：
root@ubuntu2004:~# evtest
No device specified, trying to scan all of /dev/input/event*
Available devices:
/dev/input/event0: fe6e0030.pwm
/dev/input/event1: rk805 pwrkey
/dev/input/event2: rockchip-rk809 Headset
/dev/input/event3: hdmi_cec_key
/dev/input/event4: adc-keys
/dev/input/event5: gpio-keys
Select the device event number [0-5]: 5
Input driver version is 1.0.1
Input device ID: bus 0x19 vendor 0x1 product 0x1 version 0x100
Input device name: "gpio-keys"
Supported events:
Event type 0 (EV_SYN)
Event type 1 (EV_KEY)
Event code 2 (KEY_1)
Key repeat handling:
Repeat type 20 (EV_REP)
Repeat code 0 (REP_DELAY)
Value 250
Repeat code 1 (REP_PERIOD)
Value 33
Properties:
Testing ... (interrupt to exit)
Event: time 1699275783.300685, type 1 (EV_KEY), code 2 (KEY_1), value 1
Event: time 1699275783.300685, -------------- SYN_REPORT ------------
Event: time 1699275783.573759, type 1 (EV_KEY), code 2 (KEY_1), value 2
Event: time 1699275783.573759, -------------- SYN_REPORT ------------
Event: time 1699275783.610429, type 1 (EV_KEY), code 2 (KEY_1), value 2
Event: time 1699275783.610429, -------------- SYN_REPORT ------------
Event: time 1699275783.647094, type 1 (EV_KEY), code 2 (KEY_1), value 2
Event: time 1699275783.647094, -------------- SYN_REPORT ------------
Event: time 1699275783.647094, type 1 (EV_KEY), code 2 (KEY_1), value 0
Event: time 1699275783.647094, -------------- SYN_REPORT ------------
sys gpio控制
当GPIO没有任何使用时，可以通过 /sys/class/gpio 进行控制
PIN 脚计算
GPIO1-D0 (gpio1-24)为例：
每组GPIO有32位：0-32
A（0-7）B（8-15）C（16-23）D（24-31）
GPIO1-D0 计算 Pin num = 32 * 1 + 24 = 56步骤一 确保GPIO没有任何使用
先将对应GPIO引脚注释，/sys/class/gpio/export 只能导入未注册的 gpio，将设备树对应IO取消使能
步骤二 编译镜像，重新烧录
步骤三 确认gpio未被注册
cat /sys/kernel/debug/pinctrl/pinctrl-rockchip-pinctrl/pinmux-pins未注册如下：pin 56 (gpio1-24): (MUX UNCLAIMED) (GPIO UNCLAIMED)
步骤四 对IO口进行控制
通过 /sys/class/gpio/export 注册 56并进行控制
注册
root@kickpi:~# echo 56 > /sys/class/gpio/export查看是否生成
root@kickpi:~# ls /sys/class/gpio/
export gpio56 gpiochip0 gpiochip352 unexport注册后的结点内容
root@kickpi:~# ls /sys/class/gpio/gpio56
active_low device direction edge power subsystem uevent value
root@kickpi:~#通过结点下的内容控制 gpio , 常用如下
GPIO 模式
direction
in / out
echo in > /sys/class/gpio/gpio56/direction
echo out > /sys/class/gpio/gpio56/directionin：输入
out：输出
GPIO读取及高低控制
value
0 / 1
cat /sys/class/gpio/gpio56/value
echo 1 > /sys/class/gpio/gpio56/value
echo 0 > /sys/class/gpio/gpio56/value0：低
1：高
Last updated