I2C.rar_linux i2c 2410

#include <linux/config.h> #include <linux/module.h> #include <linux/kernel.h> #include <linux/init.h> #include <linux/sched.h> #include <asm/hardware.h> #include <asm/semaphore.h> #include <asm/uaccess.h> #include <linux/kernel.h> /* printk() */ #include <linux/slab.h> /* kmalloc() */ #include <linux/fs.h> /* everything... */ #include <linux/errno.h> /* error codes */ #include <linux/types.h> /* size_t */ #include <linux/mm.h> #include <linux/kdev_t.h> #include <linux/cdev.h> #include <linux/delay.h> //#include <linux/device.h> #include <asm/io.h> #include <asm/uaccess.h> #include <linux/config.h> #include <linux/errno.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/slab.h> #include <linux/input.h> #include <linux/init.h> #include <linux/serio.h> #include <asm/irq.h> //#include <asm/arch/regs-adc.h> #include <asm/arch/map.h> #include <asm/hardware/clock.h> #include <asm/arch/regs-gpio.h> #include <asm/arch/regs-irq.h> volatile int f_nGetACK; #define UINT unsigned int #define I2C_MAGIC 'k' #define I2C_set _IO(I2C_MAGIC,1) #define I2C_MAJOR 252 #define DEVICE_NAME "s3c2410_I2C" MODULE_LICENSE("GPL"); MODULE_AUTHOR("farsight"); MODULE_DESCRIPTION("s3c2410 I2C"); char data[128]="\0"; #define S3C2410_I2C(x) ((x) + S3C2410_VA_IIC) #define S3C2410_IICCON S3C2410_I2C(0x00) #define S3C2410_IICSTAT S3C2410_I2C(0x04) #define S3C2410_IICADD S3C2410_I2C(0x08) #define S3C2410_IICDS S3C2410_I2C(0x0c) #define rIICCON *(volatile unsigned int *)S3C2410_IICCON #define rIICSTAT *(volatile unsigned int *)S3C2410_IICSTAT #define rIICADD *(volatile unsigned int *)S3C2410_IICADD #define rIICDS *(volatile unsigned int *)S3C2410_IICDS #define rGPECON *(volatile unsigned int *)S3C2410_GPECON static int I2C_major = I2C_MAJOR; static struct cdev I2C_cdev; /********************************************************************************************* * name: iic_int_24c04() * func: IIC interrupt handler * para: none * ret: none * modify: * comment: *********************************************************************************************/ static irqreturn_t iic_int_24c04(int irq,void *dev_id,struct pt_regs *regs) { //ClearPending(BIT_IIC); //printk("in I2C irq\n"); f_nGetACK = 1; return IRQ_HANDLED ; } /********************************************************************************************* * name: iic_write_24c040 * func: write data to 24C040 * para: unSlaveAddr --- input, chip slave address * unAddr --- input, data address * ucData --- input, data value * ret: none * modify: * comment: *********************************************************************************************/ void iic_write_24c040(UINT unSlaveAddr,UINT unAddr,UINT ucData) { f_nGetACK = 0; // Send control byte rIICDS = unSlaveAddr; // 0xa0 rIICSTAT = 0xf0; // Master Tx,Start // mdelay(100); while(f_nGetACK == 0);// Wait ACK f_nGetACK = 0; //Send address rIICDS = unAddr; rIICCON = 0xaf; // Resumes IIC operation. // printk("22222\n"); while(f_nGetACK == 0);// Wait ACK //printk("333333\n"); f_nGetACK = 0; // printk("2\n"); // Send data rIICDS = ucData; rIICCON = 0xaf; // Resumes IIC operation. // printk("4444444\n"); while(f_nGetACK == 0);// Wait ACK // printk("66666\n"); // Wait ACK f_nGetACK = 0; // End send rIICSTAT = 0xd0; // Stop Master Tx condition rIICCON = 0xaf; // Resumes IIC operation. mdelay(10); // Wait until stop condtion is in effect. } /********************************************************************************************* * name: iic_read_24c040 * func: read data from 24C040 * para: unSlaveAddr --- input, chip slave address * unAddr --- input, data address * pData --- output, data pointer * ret: none * modify: * comment: *********************************************************************************************/ void iic_read_24c040(UINT unSlaveAddr,UINT unAddr,unsigned char *pData) { char cRecvByte; f_nGetACK = 0; //Send control byte rIICDS = unSlaveAddr; // 0xa0 rIICSTAT = 0xf0; // Master Tx,Start while(f_nGetACK == 0);// Wait ACK f_nGetACK = 0; // Send address rIICDS = unAddr; rIICCON = 0xaf; // Resumes IIC operation. while(f_nGetACK == 0);// Wait ACK f_nGetACK = 0; //Send control byte rIICDS = unSlaveAddr; // 0xa0 rIICSTAT = 0xb0; // Master Rx,Start rIICCON = 0xaf; // Resumes IIC operation. //while(f_nGetACK == 0);// Wait ACK while(f_nGetACK == 0);// Wait ACK f_nGetACK = 0; //Get data // cRecvByte = rIICDS; rIICCON = 0x2f; mdelay(1); // Get data cRecvByte = rIICDS; // End receive rIICSTAT = 0x90; // Stop Master Rx condition rIICCON = 0xaf; // Resumes IIC operation. mdelay(10); // Wait until stop condtion is in effect. *pData = cRecvByte; } ssize_t I2C_read (struct file *filp, char *buff, size_t count, loff_t *offp) { ssize_t result = 0; int i; for(i=0; i<count; i++) data[i]=0; // Read 16 byte from 24C04 for(i=0; i<count; i++) { iic_read_24c040(0xa0, i, &(data[i])); } data[count]='\0'; // printk("rev=%s\n",data); if (copy_to_user (buff, data, count)) result = -EFAULT; //else //printk (KERN_INFO "wrote %d bytes\n", count); result=count; return result; } ssize_t I2C_write (struct file *filp, const char __user *buf, size_t count, loff_t *f_pos) { int i; ssize_t ret = 0; //printk ("Writing %d bytes\n", count); if (count>127) return -ENOMEM; if (count<0) return -EINVAL; if (copy_from_user (data, buf, count)) { ret = -EFAULT; } else { data[127]='\0'; //printk ("Received: %s\n", data); // Write 0 - 16 to 24C04 for(i=0; i<count; i++) { iic_write_24c040(0xa0, i, data[i]); //mdelay(100); } //printk("write end\n"); ret = count; } return ret; } static int I2C_open(struct inode *inode ,struct file *file) { int result; // Initialize iic rIICADD = 0x10; // S3C2410X slave address rIICCON = 0xaf; // Enable ACK, interrupt, SET IICCLK=MCLK/16 rIICSTAT = 0x10; // Enable TX/RX rGPECON =(rGPECON&((~0xf)<<28))+(0xa<<28); //printk("rGPECON=%x\n",rGPECON); result = request_irq (IRQ_IIC, iic_int_24c04,\ SA_INTERRUPT, DEVICE_NAME, NULL); if (result) { printk(KERN_INFO "I2C: can't get assigned irq\n"); } //printk(KERN_NOTICE"open the I2C now!\n"); return 0; } static int I2C_release(struct inode *inode,struct file *file) { free_irq(IRQ_IIC, NULL);//释放中断资源 //printk("I2C closed\n"); return 0; } static int I2C_ioctl(struct inode *inode,struct file *file,unsigned int cmd,unsigned long arg) { return 0; } //将设备注册到系统之中 static void I2C_setup_dev(struct cdev *dev,int minor,struct file_operations *fops) { int err; int devno=MKDEV(I2C_major,minor); cdev_init(dev,fops); dev->owner=THIS_MODULE; dev->ops=fops; err=cdev_add(dev,devno,1); if(err) printk(KERN_INFO"Error %d adding I2C %d\n",err,minor); } static struct file_operations I2C_remap_ops={ .owner=THIS_MODULE, .open=I2C_open, .write = I2C_write, .read = I2C_read, .release=I2C_release, .ioctl=I2C_ioctl, }; //注册设备驱动程序，主要完成主设备号的注册 static int __init s3c2410_I2C_init(void) { int result; dev_t dev = MKDEV(I2C_major,0); if(I2C_major) result = register_chrdev_region(dev,1,DEVICE_NAME); else { result = alloc_chrdev_region(&dev,0,1,DEVICE_NAME); I2C_major = MAJOR(dev); } if(result<0) { printk(KERN_WARN