添加APP入门实验班的LED驱动源码

04a_嵌入式Linux应用开发实验班(快速入门)/04_使用文件IO操作硬件/source/02_QT使用驱动操作LED/led_drv/01_led_imx6ull/Makefile

@@ -0,0 +1,29 @@
+
+# 1. 使用不同的开发板内核时, 一定要修改KERN_DIR
+# 2. KERN_DIR中的内核要事先配置、编译, 为了能编译内核, 要先设置下列环境变量:
+# 2.1 ARCH,          比如: export ARCH=arm64
+# 2.2 CROSS_COMPILE, 比如: export CROSS_COMPILE=aarch64-linux-gnu-
+# 2.3 PATH,          比如: export PATH=$PATH:/home/book/100ask_roc-rk3399-pc/ToolChain-6.3.1/gcc-linaro-6.3.1-2017.05-x86_64_aarch64-linux-gnu/bin 
+# 注意: 不同的开发板不同的编译器上述3个环境变量不一定相同,
+#       请参考各开发板的高级用户使用手册
+
+#KERN_DIR =  /home/book/100ask_imx6ull-sdk/Linux-4.9.88 # 板子所用内核源码的目录
+#KERN_DIR =  /home/book/100ask_imx6ull_mini-sdk/Buildroot_2020.02.x/output/build/linux-origin_master
+KERN_DIR =  /home/book/100ask_imx6ull-sdk/Buildroot_2020.02.x/output/build/linux-origin_master
+
+all:
+	make -C $(KERN_DIR) M=`pwd` modules 
+	$(CROSS_COMPILE)gcc -o led_test led_test.c
+clean:
+	make -C $(KERN_DIR) M=`pwd` modules clean
+	rm -rf modules.order  led_test
+
+# 参考内核源码drivers/char/ipmi/Makefile
+# 要想把a.c, b.c编译成ab.ko, 可以这样指定:
+# ab-y := a.o b.o
+# obj-m += ab.o
+
+
+
+obj-m += led_drv.o
+

04a_嵌入式Linux应用开发实验班(快速入门)/04_使用文件IO操作硬件/source/02_QT使用驱动操作LED/led_drv/01_led_imx6ull/led_drv.c

@@ -0,0 +1,161 @@
+#include "asm-generic/errno-base.h"
+#include "asm-generic/gpio.h"
+#include "asm/uaccess.h"
+#include <linux/module.h>
+#include <linux/poll.h>
+
+#include <linux/fs.h>
+#include <linux/errno.h>
+#include <linux/miscdevice.h>
+#include <linux/kernel.h>
+#include <linux/major.h>
+#include <linux/mutex.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <linux/stat.h>
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/tty.h>
+#include <linux/kmod.h>
+#include <linux/gfp.h>
+#include <linux/gpio/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/of_gpio.h>
+#include <linux/of_irq.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/fcntl.h>
+#include <linux/timer.h>
+
+struct gpio_desc{
+	int gpio;
+	int irq;
+    char *name;
+    int key;
+	struct timer_list key_timer;
+} ;
+
+static struct gpio_desc gpios[2] = {
+    {131, 0, "led0", },
+    //{132, 0, "led1", },
+};
+
+/* 主设备号                                                                 */
+static int major = 0;
+static struct class *gpio_class;
+
+
+/* 实现对应的open/read/write等函数，填入file_operations结构体                   */
+static ssize_t gpio_drv_read (struct file *file, char __user *buf, size_t size, loff_t *offset)
+{
+	char tmp_buf[2];
+	int err;
+    int count = sizeof(gpios)/sizeof(gpios[0]);
+
+	if (size != 2)
+		return -EINVAL;
+
+	err = copy_from_user(tmp_buf, buf, 1);
+
+	if (tmp_buf[0] >= count)
+		return -EINVAL;
+
+	tmp_buf[1] = gpio_get_value(gpios[tmp_buf[0]].gpio);
+
+	err = copy_to_user(buf, tmp_buf, 2);
+	
+	return 2;
+}
+
+static ssize_t gpio_drv_write(struct file *file, const char __user *buf, size_t size, loff_t *offset)
+{
+    unsigned char ker_buf[2];
+    int err;
+
+    if (size != 2)
+        return -EINVAL;
+
+    err = copy_from_user(ker_buf, buf, size);
+    
+    if (ker_buf[0] >= sizeof(gpios)/sizeof(gpios[0]))
+        return -EINVAL;
+
+    gpio_set_value(gpios[ker_buf[0]].gpio, ker_buf[1]);
+    return 2;    
+}
+
+
+
+/* 定义自己的file_operations结构体                                              */
+static struct file_operations gpio_key_drv = {
+	.owner	 = THIS_MODULE,
+	.read    = gpio_drv_read,
+	.write   = gpio_drv_write,
+};
+
+
+/* 在入口函数 */
+static int __init gpio_drv_init(void)
+{
+    int err;
+    int i;
+    int count = sizeof(gpios)/sizeof(gpios[0]);
+    
+	printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__);
+	
+	for (i = 0; i < count; i++)
+	{		
+		/* set pin as output */
+		err = gpio_request(gpios[i].gpio, gpios[i].name);
+		if (err < 0) {
+			printk("can not request gpio %s %d\n", gpios[i].name, gpios[i].gpio);
+			return -ENODEV;
+		}
+		
+		gpio_direction_output(gpios[i].gpio, 1);
+	}
+
+	/* 注册file_operations 	*/
+	major = register_chrdev(0, "100ask_led", &gpio_key_drv);  /* /dev/gpio_desc */
+
+	gpio_class = class_create(THIS_MODULE, "100ask_led_class");
+	if (IS_ERR(gpio_class)) {
+		printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__);
+		unregister_chrdev(major, "100ask_led_class");
+		return PTR_ERR(gpio_class);
+	}
+
+	device_create(gpio_class, NULL, MKDEV(major, 0), NULL, "100ask_led"); /* /dev/100ask_gpio */
+	
+	return err;
+}
+
+/* 有入口函数就应该有出口函数：卸载驱动程序时，就会去调用这个出口函数
+ */
+static void __exit gpio_drv_exit(void)
+{
+    int i;
+    int count = sizeof(gpios)/sizeof(gpios[0]);
+    
+	printk("%s %s line %d\n", __FILE__, __FUNCTION__, __LINE__);
+
+	device_destroy(gpio_class, MKDEV(major, 0));
+	class_destroy(gpio_class);
+	unregister_chrdev(major, "100ask_led");
+
+	for (i = 0; i < count; i++)
+	{
+		gpio_free(gpios[i].gpio);		
+	}
+}
+
+
+/* 7. 其他完善：提供设备信息，自动创建设备节点                                     */
+
+module_init(gpio_drv_init);
+module_exit(gpio_drv_exit);
+
+MODULE_LICENSE("GPL");
+
+

04a_嵌入式Linux应用开发实验班(快速入门)/04_使用文件IO操作硬件/source/02_QT使用驱动操作LED/led_drv/01_led_imx6ull/led_test.c

@@ -0,0 +1,74 @@
+
+#include <stdlib.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <string.h>
+#include <poll.h>
+#include <signal.h>
+
+static int fd;
+
+
+//int led_on(int which);
+//int led_off(int which);
+//int led_status(int which);
+
+/*
+ * ./led_test <0|1|2|..>  on 
+ * ./led_test <0|1|2|..>  off
+ * ./led_test <0|1|2|..>
+ */
+int main(int argc, char **argv)
+{
+	int ret;
+	char buf[2];
+
+	int i;
+	
+	/* 1. 判断参数 */
+	if (argc < 2) 
+	{
+		printf("Usage: %s <0|1|2|...> [on | off]\n", argv[0]);
+		return -1;
+	}
+
+
+	/* 2. 打开文件 */
+	fd = open("/dev/100ask_led", O_RDWR);
+	if (fd == -1)
+	{
+		printf("can not open file /dev/100ask_led\n");
+		return -1;
+	}
+
+	if (argc == 3)
+	{
+		/* write */
+		buf[0] = strtol(argv[1], NULL, 0);
+
+		if (strcmp(argv[2], "on") == 0)
+			buf[1] = 0;
+		else
+			buf[1] = 1;
+		
+		ret = write(fd, buf, 2);
+	}
+	else
+	{
+		buf[0] = strtol(argv[1], NULL, 0);
+		ret = read(fd, buf, 2);
+		if (ret == 2)
+		{
+			printf("led %d status is %s\n", buf[0], buf[1] == 0 ? "on" : "off");
+		}
+	}
+	
+	close(fd);
+	
+	return 0;
+}
+
+