之前实现的一个adc驱动，贴一下

Chip Platform Rockchip
1 
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/delay.h>
#include <linux/gpio.h>
#include <linux/fs.h>
#include <linux/cdev.h>
#include <linux/slab.h>
#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <asm/irq.h>
#include <linux/iio/consumer.h>

#ifdef CONFIG_OF
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/of_platform.h>
#endif

#define DESC(x) 1

#if DESC("global area")

static int global_major;
static struct class *adc0_class;
static struct device *adc0_device;
static struct device *adc0_dev = NULL;

#endif
static int adc0_probe(struct platform_device *pdev)
{
	/*Get io channel*/
	adc0_dev = &pdev->dev;
	printk("%s \n", __FUNCTION__);

	return 0;

}

static int adc0_remove(struct platform_device *pdev)
{
	return 0;
}

static const struct of_device_id of_adc0_match[] = {
	{ .compatible = "sunrex,adc_test" },
	{ /* Sentinel */ }
};

static struct platform_driver adc0_driver = {
	.probe = adc0_probe,
	.remove = adc0_remove,
	.driver = {
		.owner = THIS_MODULE,
		.name  = "adc0",
#ifdef CONFIG_OF
		.of_match_table  = of_adc0_match,
#endif
	},
};

static ssize_t adc0_read(struct file *filep, char __user *usrbuf, size_t size, loff_t *offset)
{

	int val,ret;
	struct iio_channel *chan; //定义 IIO 通道结构体

	printk("%s \n", __FUNCTION__);
	chan = iio_channel_get(adc0_dev, NULL); //获取 IIO 通道结构体
	ret = iio_read_channel_raw(chan, &val);

	printk("adc0 value = %u \n", val);
	if (ret < 0)
	{
		printk("Read channel failed. \n");
		return EIO;
	}
	copy_to_user(usrbuf, (void *)&val, size);

	 return 0;
}
static ssize_t adc0_write(struct file *filep, const char __user *usrbuf, size_t size, loff_t *offset)
{
	return 0;
}

static int adc0_open(struct inode *inode, struct file *filep)
{
	return 0;
}
static int adc0_release(struct inode *inode, struct file *filep)
{

	return 0;
}

static struct file_operations motor_fops = {
	.owner =   THIS_MODULE,
	.read  =   adc0_read,
	.write =   adc0_write,
	.open  =   adc0_open,
	.release = adc0_release,
};

static int __init adc0_init(void)
{
	/*system will auto allocate major*/
	global_major = register_chrdev(0, "adc0", &motor_fops);

	/*create class*/
	adc0_class = class_create(THIS_MODULE, "adc0_drv");

	/*create device for app*/
	adc0_device = device_create(adc0_class, NULL, MKDEV(global_major, 0), NULL, "adc0");

	//if (ret < 0)
	//	return ret;
	platform_driver_register(&adc0_driver);
	return 0;
}

static void __exit adc0_exit(void)
{
	platform_driver_unregister(&adc0_driver);
	device_destroy(adc0_class,MKDEV(global_major, 0));
	class_destroy(adc0_class);
	//unregister_chrdev_region(MKDEV(global_major, 0), 1);
	unregister_chrdev(global_major, "adc0");
}

module_init(adc0_init);
module_exit(adc0_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("zhang jiawei");
2

正在看这方面的内容，先收藏！谢谢！

3

ADC MARK