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AD_DRIVER

#include

#include "s3c2410-adc.h"

#undef DEBUG

//#define DEBUG

#ifdef DEBUG

#define DPRINTK(x...) {printk(__FUNCTION__"(%d): ",__LINE__);printk(##x);} #else

#define DPRINTK(x...) (void)(0)

#endif

#define DEVICE_NAME "s3c2410-adc"

#define ADCRAW_MINOR 1

static int adcMajor = 0;

typedef struct {

struct semaphore lock;

wait_queue_head_t wait;

int channel;

int prescale;

}ADC_DEV;

static ADC_DEV adcdev;

#define START_ADC_AIN(ch, prescale) \

do{ \

ADCCON = PRESCALE_EN | PRSCVL(prescale) | ADC_INPUT((ch)) ; \

ADCCON |= ADC_START; \

}while(0)

static void adcdone_int_handler(int irq, void *dev_id, struct pt_regs *reg)

{

wake_up(&adcdev.wait);

}

static ssize_t s3c2410_adc_write(struct file *file, const char *buffer, size_t count, loff_t * ppos) {

int data;

if(count!=sizeof(data)){

//error input data size

DPRINTK("the size of input data must be %d\n", sizeof(data));

return 0;

}

copy_from_user(&data, buffer, count);

adcdev.channel=ADC_WRITE_GETCH(data);

adcdev.prescale=ADC_WRITE_GETPRE(data);

DPRINTK("set adc channel=%d, prescale=0x%x\n", adcdev.channel, adcdev.prescale);

return count;

}

static ssize_t s3c2410_adc_read(struct file *filp, char *buffer, size_t count, loff_t *ppos)

{

int ret = 0;

if (down_interruptible(&adcdev.lock))

return -ERESTARTSYS;

START_ADC_AIN(adcdev.channel, adcdev.prescale);

interruptible_sleep_on(&adcdev.wait);

ret = ADCDAT0;

ret &= 0x3ff;

DPRINTK("AIN[%d] = 0x%04x, %d\n", adcdev.channel, ret, ADCCON & 0x80 ? 1:0);

copy_to_user(buffer, (char *)&ret, sizeof(ret));

up(&adcdev.lock);

return sizeof(ret);

}

static int s3c2410_adc_open(struct inode *inode, struct file *filp)

{

init_MUTEX(&adcdev.lock);

init_waitqueue_head(&(adcdev.wait));

adcdev.channel=0;

adcdev.prescale=0xff;

MOD_INC_USE_COUNT;

DPRINTK( "adc opened\n");

return 0;

}

static int s3c2410_adc_release(struct inode *inode, struct file *filp)

{

MOD_DEC_USE_COUNT;

DPRINTK( "adc closed\n");

return 0;

}

static struct file_operations s3c2410_fops = {

owner: THIS_MODULE,

open: s3c2410_adc_open,

read:s3c2410_adc_read,

write: s3c2410_adc_write,

release: s3c2410_adc_release,

};

#ifdef CONFIG_DEVFS_FS

static devfs_handle_t devfs_adc_dir, devfs_adcraw;

#endif

int __init s3c2410_adc_init(void)

{

int ret;

/* normal ADC */

ADCTSC = 0; //XP_PST(NOP_MODE);

ret = request_irq(IRQ_ADC_DONE, adcdone_int_handler, SA_INTERRUPT, DEVICE_NAME, NULL);

if (ret) {

return ret;

}

ret = register_chrdev(0, DEVICE_NAME, &s3c2410_fops);

if (ret < 0) {

printk(DEVICE_NAME " can't get major number\n");

return ret;

}

adcMajor=ret;

#ifdef CONFIG_DEVFS_FS

devfs_adc_dir = devfs_mk_dir(NULL, "adc", NULL);

devfs_adcraw = devfs_register(devfs_adc_dir, "0raw", DEVFS_FL_DEFAULT,

adcMajor, ADCRAW_MINOR, S_IFCHR | S_IRUSR | S_IWUSR, &s3c2410_fops, NULL);

#endif

printk (DEVICE_NAME"\tinitialized\n");

return 0;

}

module_init(s3c2410_adc_init);

#ifdef MODULE

void __exit s3c2410_adc_exit(void)

{

#ifdef CONFIG_DEVFS_FS

devfs_unregister(devfs_adcraw);

devfs_unregister(devfs_adc_dir);

#endif

unregister_chrdev(adcMajor, DEVICE_NAME);

free_irq(IRQ_ADC_DONE, NULL);

}

module_exit(s3c2410_adc_exit);

MODULE_LICENSE("GPL");

#endif