| /*
* linux/derivers/led/led-edukit-s3c2410.c
* led driver for Embest EduKit II
* Copyright (C) 2005 Embest
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/errno.h> // error codes
#include <linux/types.h> // size_t
#include <linux/delay.h> // mdelay
#include <linux/proc_fs.h>
#include <asm/uaccess.h> // to copy to/from userspace
#include <asm/hardware.h>
#include <asm/arch-s3c2410/S3C2410.h>
#include <asm/leds.h>
#ifdef LED_DEBUG // if want to debug, define it while compile this function
#define DEBUG(str, args...) printk("led: " str, ## args)
#else
#define DEBUG(str, args...)
#endif
#undef u32
#define u32 unsigned
static int nLedMajor = 0; /* allow to alloc the major number for led*/
#define LED_DEVNAME "led"
#define GPF_MASK (0xF<<4) /* GPF4-7: LED1-LED4 */
#define GET_DATA(f) ((u8)(~f>>4))
#define SET_DATA(t, f) ( f = (~t&0x0F)<<4 )
#define LED_LOCK(u) down(&u->lock);
#define LED_UNLOCK(u) up(&u->lock);
#define GPF_CTL_BASE io_p2v(0x56000050)/* get the virtual address map to GPF */
#define S3C2410_GPFCON (GPF_CTL_BASE + 0x0)
#define S3C2410_GPFDAT (GPF_CTL_BASE + 0x4)
#define S3C2410_GPFUP (GPF_CTL_BASE + 0x8)
unsigned long flags;
static char *version = "Embest EdukitII-2410 led driver version 1.0 (2005-06-18) \n";
struct unit {
struct semaphore lock;
u32 *GPF_CON; /* GPFCON register */
u32 *GPF_DAT; /* GPFDAT register */
u32 *GPF_UP; /* GPFUP register */
u32 f; /* LEDs value (bit4-7:LED1-LED4)*/
};
static struct unit led_unit = {
.GPF_CON = (u32 *)S3C2410_GPFCON,
.GPF_DAT = (u32 *)S3C2410_GPFDAT,
.GPF_UP = (u32 *)S3C2410_GPFUP,
.f = 0x00 // turn on all LEDs
};
#ifdef CONFIG_PROC_FS
static int led_proc(char *page, char **start, off_t off,
int count, int *eof, void *data)
{
char *p = page;
int len;
struct unit led_u;
len = led_u.f;
p += sprintf(p, "%s\n LED1: %s LED2: %s LED3: %s LED4: %s \n", version,
len&(1<<4)?"ON":"OFF",
len&(1<<5)?"ON":"OFF",
len&(1<<6)?"ON":"OFF",
len&(1<<7)?"ON":"OFF"
);
len = (p - page) - off;
if (len < 0)
len = 0;
*eof = (len <= count) ? 1 : 0;
*start = page + off;
return len;
}
#endif
static void led_set_value(struct unit *unit, u8 val)
{
u32 temp;
SET_DATA(val, unit->f);
temp = *unit->GPF_DAT;
temp &= ~GPF_MASK;
temp |= unit->f;
*unit->GPF_DAT = temp;
DEBUG("write to GPFDAT:0x%x.\n", temp);
}
static u8 led_get_value(struct unit *unit)
{
u8 temp = GET_DATA(unit->f);
return temp;
}
static int led_open(struct inode *inode, struct file *file)
{
DEBUG("open\n");
leds_event(led_stop);
file->private_data = &led_unit;
MOD_INC_USE_COUNT;
return 0;
}
static int led_release_f(struct inode *inode, struct file *file)
{
DEBUG("release\n");
MOD_DEC_USE_COUNT;
leds_event(led_start);
return 0;
}
static ssize_t led_read(struct file *file, char *buf, size_t count, loff_t *offset)
{
u8 temp;
int ret;
struct unit *unit = (struct unit *)file->private_data;
DEBUG("read\n");
if(count > 1)
count = 1;
LED_LOCK(unit);
temp = led_get_value(unit);
DEBUG("Read from unit value field:0x%x.\n", temp);
ret = copy_to_user(buf, &temp, count) ? -EFAULT : count;
LED_UNLOCK(unit);
return ret;
}
static ssize_t led_write(struct file *file, const char *buf, size_t count, loff_t *offset)
{
u8 temp;
int ret;
char *tmp;
struct unit *unit = (struct unit *)file->private_data;
DEBUG("write\n");
if(count > 1)
count = 1;
LED_LOCK(unit);
ret = copy_from_user(&temp, buf, count) ? -EFAULT : count;
DEBUG("led0 writing %d bytes:0x%x.\n", ret,temp);
if(ret)
led_set_value(unit, temp);
LED_UNLOCK(unit);
return ret;
}
static struct file_operations led_ops = {
owner: THIS_MODULE,
read: led_read,
write: led_write,
open: led_open,
release: led_release_f,
};
/*
* led device init
*/
static void __init led_init(struct unit *unit)
{
u32 temp;
/* init device lock */
init_MUTEX(&unit->lock);
/* init io port */
temp = *unit->GPF_CON;
temp &= ~(0xF<<4);
temp |= ((1<<14) | (1<<12) | (1<<10) | (1<<8));// GPF4,5,6,7 as Output
*unit->GPF_CON = temp;
temp = *unit->GPF_UP;
temp |= (0xF<<8);// pull up all GPF4,5,6,7
*unit->GPF_UP = temp;
/* init data and turn on led, bit0-3:LED1-4*/
led_set_value(unit, 0x0f);
/* delay some time */
mdelay(100);
/* turn off led */
led_set_value(unit, 0x00);
}
/*
* module init
*/
static devfs_handle_t devfs_handle,devfs_led_dir;
#ifdef MODULE
int init_module(void)
#else
int __init led_init_module(void)
#endif
{
int res;
DEBUG("init_module\n");
/* print version information */
printk(KERN_INFO "%s", version);
/* register led device, character device: /proc/devices*/
#ifdef CONFIG_DEVFS_FS
res = devfs_register_chrdev(0, LED_DEVNAME, &led_ops);
if(res < 0) {
printk("led-edukit-s3c2410.o: unable to get major for led device.\n");
return res;
}
/* create the devfs: /driver/led/0 */
devfs_led_dir = devfs_mk_dir(NULL, LED_DEVNAME, NULL);
devfs_handle = devfs_register(devfs_led_dir, "0", DEVFS_FL_DEFAULT,
res, 0,S_IFCHR | S_IRUSR | S_IWUSR,&led_ops, NULL);
#else
res = register_chrdev(nLedMajor, LED_DEVNAME, &led_ops);
#endif
/* add a profile to /proc/driver/led */
#ifdef CONFIG_PROC_FS
create_proc_read_entry ("driver/led", 0, 0, led_proc, NULL);
#endif
/* get the major number */
if( nLedMajor == 0 )
{
nLedMajor = res;
printk("Led major number = %d\n",nLedMajor);
}
/* then call led_init() */
led_init(&led_unit);
return 0;
}
/*
* module cleanup
*/
#ifdef MODULE
void cleanup_module(void)
#else
void __exit led_cleanup(void)
#endif
{
int res;
DEBUG("cleanup\n");
/* unregister led device */
res = unregister_chrdev(nLedMajor, LED_DEVNAME);
if(res < 0)
printk("led-edukit-s3c2410.o: unable to release major %d for led device.\n", nLedMajor);
#ifdef CONFIG_DEVFS_FS
devfs_unregister(devfs_handle);
devfs_unregister(devfs_led_dir);
#endif
/* remove the profile /proc/driver/led */
#ifdef CONFIG_PROC_FS
remove_proc_entry("driver/led", NULL);
#endif
}
#ifndef MODULE
/* declare a module init entry */
module_init(led_init_module);
/* declare a module exit entry */
module_exit(led_cleanup);
#endif
MODULE_DESCRIPTION("EduKitII-2410 led driver");
MODULE_AUTHOR("Embest tech&info Co.,Ltd. ");
MODULE_LICENSE("GPL"); |
