openwrt/target/linux/brcm-2.4/files/arch/mips/bcm947xx/gpio.c

158 lines
3.0 KiB
C

/*
* GPIO char driver
*
* Copyright 2005, Broadcom Corporation
* All Rights Reserved.
*
* THIS SOFTWARE IS OFFERED "AS IS", AND BROADCOM GRANTS NO WARRANTIES OF ANY
* KIND, EXPRESS OR IMPLIED, BY STATUTE, COMMUNICATION OR OTHERWISE. BROADCOM
* SPECIFICALLY DISCLAIMS ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A SPECIFIC PURPOSE OR NONINFRINGEMENT CONCERNING THIS SOFTWARE.
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <asm/uaccess.h>
#include <typedefs.h>
#include <osl.h>
#include <sbutils.h>
#include <bcmdevs.h>
static sb_t *gpio_sbh;
static int gpio_major;
static devfs_handle_t gpio_dir;
static struct {
char *name;
devfs_handle_t handle;
} gpio_file[] = {
{ "in", NULL },
{ "out", NULL },
{ "outen", NULL },
{ "control", NULL }
};
static int
gpio_open(struct inode *inode, struct file * file)
{
if (MINOR(inode->i_rdev) > ARRAYSIZE(gpio_file))
return -ENODEV;
MOD_INC_USE_COUNT;
return 0;
}
static int
gpio_release(struct inode *inode, struct file * file)
{
MOD_DEC_USE_COUNT;
return 0;
}
static ssize_t
gpio_read(struct file *file, char *buf, size_t count, loff_t *ppos)
{
u32 val;
switch (MINOR(file->f_dentry->d_inode->i_rdev)) {
case 0:
val = sb_gpioin(gpio_sbh);
break;
case 1:
val = sb_gpioout(gpio_sbh, 0, 0, GPIO_DRV_PRIORITY);
break;
case 2:
val = sb_gpioouten(gpio_sbh, 0, 0, GPIO_DRV_PRIORITY);
break;
case 3:
val = sb_gpiocontrol(gpio_sbh, 0, 0, GPIO_DRV_PRIORITY);
break;
default:
return -ENODEV;
}
if (put_user(val, (u32 *) buf))
return -EFAULT;
return sizeof(val);
}
static ssize_t
gpio_write(struct file *file, const char *buf, size_t count, loff_t *ppos)
{
u32 val;
if (get_user(val, (u32 *) buf))
return -EFAULT;
switch (MINOR(file->f_dentry->d_inode->i_rdev)) {
case 0:
return -EACCES;
case 1:
sb_gpioout(gpio_sbh, ~0, val, GPIO_DRV_PRIORITY);
break;
case 2:
sb_gpioouten(gpio_sbh, ~0, val, GPIO_DRV_PRIORITY);
break;
case 3:
sb_gpiocontrol(gpio_sbh, ~0, val, GPIO_DRV_PRIORITY);
break;
default:
return -ENODEV;
}
return sizeof(val);
}
static struct file_operations gpio_fops = {
owner: THIS_MODULE,
open: gpio_open,
release: gpio_release,
read: gpio_read,
write: gpio_write,
};
static int __init
gpio_init(void)
{
int i;
if (!(gpio_sbh = sb_kattach(SB_OSH)))
return -ENODEV;
sb_gpiosetcore(gpio_sbh);
if ((gpio_major = devfs_register_chrdev(0, "gpio", &gpio_fops)) < 0)
return gpio_major;
gpio_dir = devfs_mk_dir(NULL, "gpio", NULL);
for (i = 0; i < ARRAYSIZE(gpio_file); i++) {
gpio_file[i].handle = devfs_register(gpio_dir,
gpio_file[i].name,
DEVFS_FL_DEFAULT, gpio_major, i,
S_IFCHR | S_IRUGO | S_IWUGO,
&gpio_fops, NULL);
}
return 0;
}
static void __exit
gpio_exit(void)
{
int i;
for (i = 0; i < ARRAYSIZE(gpio_file); i++)
devfs_unregister(gpio_file[i].handle);
devfs_unregister(gpio_dir);
devfs_unregister_chrdev(gpio_major, "gpio");
sb_detach(gpio_sbh);
}
module_init(gpio_init);
module_exit(gpio_exit);