GPIO子系统点六盏灯

#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
struct device_node* node;
struct device_node* child_node1;
struct device_node* child_node2;
unsigned int gpionumb1[3];
unsigned int gpionumb2[3];
char *name[3]={"led1","led2","led3"};//字符指针数组
int i=0;
static int __init my_init(void)
{//解析设备树myled节点node=of_find_node_by_path("/myled");if(node==NULL){printk("node error:");return -EIO;}child_node1 = of_get_child_by_name(node,"extend-led");if(child_node1==NULL){printk("node error:");return -EIO;}child_node2 = of_get_child_by_name(node,"core-led");if(child_node2==NULL){printk("node error:");return -EIO;}for(i=0;i<3;i++){//从设备树中读取gpio编号gpionumb1[i]=of_get_named_gpio(child_node1,name[i],0);if(gpionumb1[i]<0){printk("of get name gpio is error:");return -EIO;}//申请gpio编号gpio_request(gpionumb1[i],NULL);//设置gpio编号输出高电平gpio_direction_output(gpionumb1[i],1);//从设备树中读取gpio编号gpionumb2[i]=of_get_named_gpio(child_node2,"led",i);if(gpionumb2[i]<0){printk("of get name gpio is error:");return -EIO;}//申请gpio编号gpio_request(gpionumb2[i],NULL);//设置gpio编号输出高电平gpio_direction_output(gpionumb2[i],1);}return 0;
} static void __exit my_exit(void)
{for(i=0;i<3;i++){//设置gpio编号输出低电平gpio_direction_output(gpionumb1[i],0);//释放gpio编号gpio_free(gpionumb1[i]);//设置gpio编号输出低电平gpio_direction_output(gpionumb2[i],0);//释放gpio编号gpio_free(gpionumb2[i]);}
}
module_init(my_init);
module_exit(my_exit);
MODULE_LICENSE("GPL");

GPIOD子系统点六盏灯

#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
struct device_node* node;
struct device_node* child_node1_expend;
struct device_node* child_node2_core;
unsigned int gpionumb1[3];
unsigned int gpionumb2[3];
struct gpio_desc* edesc[3];
struct gpio_desc* cdesc[3];
char *name[3]={"led1","led2","led3"};//字符指针数组
int i=0;
/*
myled{ //添加基于gpio子系统设备树节点core-led{ //核心板子节点led = <&gpioz 5 0>,<&gpioz 6 0>,<&gpioz 7 0>;};extend-led{ //扩展板子节点led1 = <&gpioe 10 0>; //led1 PE10led2 = <&gpiof 10 0>; //led2 PF10led3 = <&gpioe 8 0>; //led3 PE8};
};  
*/
static int __init my_init(void)
{//解析设备树myled节点node=of_find_node_by_path("/myled");if(node==NULL){printk("node error:");return -EIO;}//扩展板LED子节点child_node1_expend = of_get_child_by_name(node,"extend-led");if(child_node1_expend==NULL){printk("node error:");return -EIO;}//核心板LED子节点child_node2_core = of_get_child_by_name(node,"core-led");if(child_node2_core==NULL){printk("node error:");return -EIO;}for(i=0;i<3;i++){//直接从设备中获取struct gpio_desc*结构体指针edesc[i]=gpiod_get_from_of_node(child_node1_expend,name[i],0,GPIOD_OUT_LOW,NULL);if(IS_ERR(edesc[i])){//判断地址是否在4K空间内printk("gpiod get from node is error\n");return PTR_ERR(edesc[i]);//将地址转换成错误码}gpiod_direction_output(edesc[i],1);//设置gpio引脚输出高电平cdesc[i]=gpiod_get_from_of_node(child_node2_core,"led",i,GPIOD_OUT_LOW,NULL);if(IS_ERR(cdesc[i])){//判断地址是否在4K空间内printk("gpiod get from node is error\n");return PTR_ERR(cdesc[i]);//将地址转换成错误码}gpiod_direction_output(cdesc[i],1);//设置gpio引脚输出高电平}return 0;
} static void __exit my_exit(void)
{for(i=0;i<3;i++){//设置gpio编号输出低电平gpiod_set_value(edesc[i],0);//释放gpio编号gpiod_put(edesc[i]);//设置gpio编号输出低电平gpiod_set_value(cdesc[i],0);//释放gpio编号gpiod_put(cdesc[i]);}
}
module_init(my_init);
module_exit(my_exit);
MODULE_LICENSE("GPL");