海思LSADC驱动源码，dv300等适用。

#include <linux/module.h> #include <linux/fs.h> #include <linux/init.h> #include <linux/cdev.h> #include <linux/slab.h> #include <linux/string.h> #include <linux/device.h> #include <linux/ioport.h> #include <linux/kernel.h> #include <linux/cdev.h> #include <linux/delay.h> #include <asm/uaccess.h> #include <asm/io.h> #include <linux/ioctl.h> #include <linux/uaccess.h> #define IOC_MAGIC 'c' /* 初始化设备 */ #define IOCINIT _IO(IOC_MAGIC, 0) /* 读寄存器 */ #define IOCGREG _IOW(IOC_MAGIC, 1, int) /* 写寄存器 */ #define IOCWREG _IOR(IOC_MAGIC, 2, int) #define IOC_MAXNR 3 //连续扫描 #define Continuous_Scanning //#define Single_Scanning #define MAX_SIZE 0x1000 #define MEM_CLEAR 0x1 #define LSADC_RGG_BASE_ADDR 0x11080000 #define LSADC_REG(x) baseaddr+(x) #define LSADC_CTRL0 LSADC_REG(0x0000) #define LSADC_CTRL1 LSADC_REG(0x0004) #define LSADC_CTRL2 LSADC_REG(0x0008) #define LSADC_CTRL4 LSADC_REG(0x0010) #define LSADC_CTRL5 LSADC_REG(0x0014) #define LSADC_CTRL6 LSADC_REG(0x0018) #define LSADC_CTRL7 LSADC_REG(0x001c) #define LSADC_CTRL8 LSADC_REG(0x0020) #define LSADC_CTRL9 LSADC_REG(0x0024) #define LSADC_CTRL10 LSADC_REG(0x0028) #define LSADC_CTRL11 LSADC_REG(0x002C) #define LSADC_CTRL12 LSADC_REG(0x0030) #define LSADC_CTRL13 LSADC_REG(0x0034) #define LSADC_CTRL14 LSADC_REG(0x0038) static void __iomem *baseaddr; // 寄存器的虚拟地址的基地址 static struct class *cls; static struct device *dev; static int lsadc_major; struct virtdev_dev { struct cdev cdev; unsigned char mem[MAX_SIZE]; }; struct virtdev_dev *devp; dev_t devno; struct msg { int addr; unsigned int data; }; static int virtdev_open(struct inode *inode, struct file *filp) { *devp->mem = "0x1234567890"; filp->private_data = devp; return 0; } static int virtdev_release(struct inode *inode, struct file *filp) { return 0; } static long virtdev_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { long ret; struct msg my_msg; //printk(KERN_EMERG"[%s] command numer [%d] exceeded!\n", // __func__, _IOC_NR(cmd)); switch (cmd) { /* 初始化设备 */ case IOCINIT: printk(KERN_EMERG"__init\n"); break; /* 读寄存器 */ case IOCGREG: // printk(KERN_EMERG"__read\n"); ret = copy_from_user(&my_msg, \ (struct msg __user *)arg, sizeof(my_msg)); if (ret) return -EFAULT; #ifdef Single_Scanning writel(0x1, LSADC_CTRL7); #endif // Single_Scanning my_msg.data = readl(LSADC_CTRL11);//ADC CHN0 ret = copy_to_user((struct msg __user *)arg, \ &my_msg, sizeof(my_msg)); if (ret) return -EFAULT; break; /* 写寄存器 */ case IOCWREG: //printk(KERN_EMERG"__write\n"); ret = copy_from_user(&my_msg, \ (struct msg __user *)arg, sizeof(my_msg)); printk(KERN_EMERG"msg addr is %x,value is %x\n",my_msg.addr, my_msg.data); if (ret) return -EFAULT; //write_reg(msg->addr, msg->data); break; default: return -ENOTTY; } return 0; } static ssize_t virtdev_read(struct file *filp, char __user *buf, size_t size, loff_t *ppos) { unsigned long p = *ppos; unsigned int count = size; int ret = 0; struct virtdev_dev *dev = filp->private_data; if (p >= MAX_SIZE) return -EINVAL; if (count > MAX_SIZE - p) count = MAX_SIZE - p; if (copy_to_user(buf, dev->mem + p, count)) ret = -EINVAL; else { *ppos += count; ret = count; printk(KERN_INFO "read %u byte(s) from %lu\n", count, p); } return ret; } static ssize_t virtdev_write(struct file *filp, const char __user *buf, size_t size, loff_t *ppos) { unsigned long p = *ppos; unsigned int count = size; int ret = 0; struct virtdev_dev *dev = filp->private_data; if (p >= MAX_SIZE) return -EINVAL; if (count > MAX_SIZE - p) count = MAX_SIZE - p; if (copy_from_user(dev->mem + p, buf, count)) ret = -EINVAL; else { *ppos += count; ret = count; printk(KERN_INFO "write %u byte(s) from %lu\n", count, p); } return ret; } static loff_t virtdev_llseek(struct file *filp, loff_t offset, int orig) { loff_t ret = 0; switch (orig) { case 0: if (offset < 0) { ret = -EINVAL; break; } if (offset > MAX_SIZE) { ret = -EINVAL; break; } filp->f_pos = offset; ret = filp->f_pos; break; case 1: if ((filp->f_pos + offset) < 0) { ret = -EINVAL; break; } if ((filp->f_pos + offset) > MAX_SIZE) { ret = -EINVAL; break; } filp->f_pos += offset; ret = filp->f_pos; break; default: ret = -EINVAL; break; } return ret; } static struct file_operations virtdev_fops = { .llseek = virtdev_llseek, .read = virtdev_read, .write = virtdev_write, .unlocked_ioctl = virtdev_ioctl, .open = virtdev_open, .release= virtdev_release, }; static char *chardev_devnode(struct device *dev, umode_t *mode) { if (mode) *mode = 0666; return NULL; } static int __init lsadc_init(void) { int ret; int err; ret = alloc_chrdev_region(&devno, 0, 1, "lsadc"); lsadc_major = MAJOR(devno); devp = kzalloc(sizeof(struct virtdev_dev), GFP_KERNEL); cls = class_create(NULL, "lsadc");//第一个参数指定类的所有者是哪个模块，第二个参数指定类名。 dev = device_create(cls, NULL, devno, NULL, "lsadc");//第一个参数指定所要创建的设备所从属的类， //第二个参数是这个设备的父设备，如果没有就指定为NULL， cdev_init(&devp->cdev, &virtdev_fops); devp->cdev.owner = THIS_MODULE; err = cdev_add(&devp->cdev, devno, 1); if (!request_mem_region(LSADC_RGG_BASE_ADDR, 52, "GPJ0BASE")) return -EINVAL; baseaddr = ioremap(LSADC_RGG_BASE_ADDR, 52); writel(0xFFF004FF, LSADC_CTRL0); writel(0x1, LSADC_CTRL4); writel(0x1, LSADC_CTRL7); return 0; } static void __exit lsadc_exit(void) { device_unregister(dev); class_destroy(cls); device_destroy(cls, devno); cdev_del(&devp->cdev); kfree(devp); unregister_chrdev_region(devno,1); iounmap(baseaddr); release_mem_region(baseaddr, 52); } module_init(lsadc_init); module_exit(lsadc_exit); MODULE_AUTHOR("Public"); MODULE_LICENSE("GPL");