11.8代码

利用gpiod子系统实现开发板六盏灯，安装驱动点亮，卸载驱动熄灭

#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
/*myleds{core-leds{leds = <&gpioz 5 0>,<&gpioz 6 0>,<&gpioz 7 0>;};extend-leds{led1 = <&gpioe 10 0>;led2 = <&gpiof 10 0>;led3 = <&gpioe 8 0>;};};
*/
struct device_node *node;
struct device_node *core_node;
struct device_node *extend_node;
struct gpio_desc *core_desc[3];
struct gpio_desc *extend_desc[3];
char *extend_leds[3] = {"led1", "led2", "led3"};
// 入口
static int __init demo_init(void)
{int i;// 获取父结点node = of_find_node_by_path("/myleds");if (node == NULL){printk("of_find_node_by_path is error\n");return -EIO;}// 获取core子节点core_node = of_get_child_by_name(node, "core-leds");if (core_node == NULL){printk("core of_get_child_by_name is error\n");return -EIO;}// 获取extend子节点extend_node = of_get_child_by_name(node, "extend-leds");if (node == NULL){printk("extend of_get_child_by_name is error\n");return -EIO;}for (i = 0; i < 3; i++){// 获取gpio结构体core_desc[i] = gpiod_get_from_of_node(core_node, "leds", i, GPIOD_OUT_HIGH, NULL);// 申请gpio编号gpiod_get_value(core_desc[i]);// 设置gpio输出为1gpiod_direction_output(core_desc[i], 1);}for (i = 0; i < 3; i++){// 获取gpio结构体extend_desc[i] = gpiod_get_from_of_node(extend_node, extend_leds[i], 0, GPIOD_OUT_HIGH, NULL);// 申请gpio编号gpiod_get_value(extend_desc[i]);// 设置gpio输出为1gpiod_direction_output(extend_desc[i], 1);}return 0;
}
// 出口
static void __exit demo_exit(void)
{int i;for (i = 0; i < 3; i++){// 设置gpio输出为0gpiod_direction_output(core_desc[i], 0);// 释放gpio编号gpiod_put(core_desc[i]);}for (i = 0; i < 3; i++){// 设置gpio输出为0gpiod_direction_output(extend_desc[i], 0);// 释放gpio编号gpiod_put(extend_desc[i]);}
}module_init(demo_init);
module_exit(demo_exit);
MODULE_LICENSE("GPL"); // 许可证

使用linux中断子系统完成三个按键编写

#include <linux/init.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/interrupt.h>
/*mykeys{interrupt-parent=<&gpiof>;interrupts = <9 0>,<7 0>,<8 0>;};
*/
irqreturn_t key1_irq_handler(int irq, void *dev)
{int key = (int)dev;switch (key){case 0:printk("key1 down!!!\n");break;case 1:printk("key2 down!!!\n");break;case 2:printk("key3 down!!!\n");break;default:break;}return IRQ_HANDLED;
}
unsigned int irqnu[3];
char *irname[3] = {"key1", "key2", "key3"};
struct device_node *node;// 入口
static int __init demo_init(void)
{int i;int ret;// 获取结点node = of_find_node_by_path("/mykeys");if (node == NULL){printk("of_find_node_by_path is error\n");return -EIO;}for (i = 0; i < 3; i++){// 获取软中断号irqnu[i] = irq_of_parse_and_map(node, i);// 注册中断子系统ret = request_irq(irqnu[i], key1_irq_handler, IRQF_TRIGGER_FALLING, irname[i], (void *)i);if (ret < 0){printk("%d request_irq is error\n", irqnu[i]);return -EIO;}}return 0;
}
// 出口
static void __exit demo_exit(void)
{int i;for (i = 0; i < 3; i++){// 注销中断free_irq(irqnu[i], NULL);}
}module_exit(demo_exit);
module_init(demo_init);
MODULE_LICENSE("GPL"); // 许可证