platform总线、设备、驱动模型之led驱动实例

1 struct bus_type platform_bus_type = {
2 .name = "platform",
3 .dev_attrs = platform_dev_attrs,
4 .match = platform_match,
5 .uevent = platform_uevent,
6 .pm = PLATFORM_PM_OPS_PTR,
7 };
8 EXPORT_SYMBOL_GPL(platform_bus_type);

led_dev.c:定义资源

#include <linux/module.h>
#include <linux/version.h>

#include <linux/init.h>

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/interrupt.h>
#include <linux/list.h>
#include <linux/timer.h>
#include <linux/init.h>
#include <linux/serial_core.h>
#include <linux/platform_device.h>


/* 分配/设置/注册一个platform_device */

static struct resource led_resource[] = {
    [0] = {
        .start = 0xE0200C40,
        .end   = 0xE0200C40 + 8 - 1,
        .flags = IORESOURCE_MEM,
    },
    [1] = {
        .start = 4,
        .end   = 4,
        .flags = IORESOURCE_IRQ,
    }

};

static void led_release(struct device * dev)
{
}


static struct platform_device led_dev = {
    .name         = "<span style="color:#ff6666;">myled</span>",
    .id       = -1,
    .num_resources    = ARRAY_SIZE(led_resource),
    .resource     = led_resource,
    .dev = { 
    	.release = led_release, 
	},
};

static int led_dev_init(void)
{
	platform_device_register(&led_dev);
	return 0;
}

static void led_dev_exit(void)
{
	platform_device_unregister(&led_dev);
}

module_init(led_dev_init);
module_exit(led_dev_exit);

MODULE_LICENSE("GPL");

led_drv.c驱动程序：

/* 分配/设置/注册一个platform_driver */

#include <linux/module.h>
#include <linux/version.h>

#include <linux/init.h>
#include <linux/fs.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/sched.h>
#include <linux/pm.h>
#include <linux/sysctl.h>
#include <linux/proc_fs.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/input.h>
#include <linux/irq.h>
#include <asm/uaccess.h>
#include <asm/io.h>

static int major;


static struct class *cls;
static volatile unsigned long *gpio_con;
static volatile unsigned long *gpio_dat;
static int pin;


static int leds_open(struct inode *inode, struct file *file)
{
    printk("led_open\n");

	*gpio_con = 0x11111111;
	
    return 0;
}



static long leds_ioctl(struct file *filp,unsigned int cmd,unsigned long arg) 
{  
	printk("use ioctl\n");
	
	
	if(cmd == 1){
		printk("arg = = %d\n",arg);
		printk("cmd = = %d\n",cmd);
		*gpio_dat =0x1f;// ~(0<<4);
		printk("gpio_dat == %0x\n",*gpio_dat);
	}
	else
   		*gpio_dat &= 0x00;
} 


static struct file_operations led_fops = {
    .owner  =   THIS_MODULE,    /* 这是一个宏，推向编译模块时自动创建的__this_module变量 */
	.open    = leds_open,
    .unlocked_ioctl = leds_ioctl,
};

static int led_probe(struct platform_device *pdev)
{

	struct resource *res;

	res = platform_get_resource(pdev,IORESOURCE_MEM,0);
	gpio_con = ioremap(res->start,res->end - res->start + 1);
	gpio_dat = gpio_con + 1;

	res = platform_get_resourse(pdev,IORESOURCE_IRQ,0);
	pin = res -> start;

	printk("led probe\n");

	major = register_chrdev(0 , "myled", &led_fops);

	cls = class_create(THIS_MODULE,"myled");

	class_device_create(cls,NULL,MKDEV(major,0),NULL,"led");
	
	return 0;
}

static int led_remove(struct platform_device *pdev)
{
	printk("led remove\n");
	
	return 0;
}


struct platform_driver led_drv = {
	.probe		= led_probe,
	.remove		= led_remove,
	.driver		= {
		.name	= "<span style="color:#ff6666;">myled</span>",
	}
};


static int led_drv_init(void)
{
	platform_driver_register(&led_drv);
	return 0;
}

static void led_drv_exit(void)
{
	platform_driver_unregister(&led_drv);
}

module_init(led_drv_init);
module_exit(led_drv_exit);

MODULE_LICENSE("GPL");