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/*
* serial_acm.c -- USB modem serial driver
*
* Copyright 2008 (C) Samsung Electronics
*
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/fcntl.h>
#include <linux/device.h>
#include <linux/miscdevice.h>
#include <linux/uaccess.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/sched.h>
#include <linux/wait.h>
#include <linux/poll.h>
#include <linux/usb/cdc.h>
static int acm_notify(void *dev, u16 state);
static wait_queue_head_t modem_wait_q;
static unsigned int read_state;
static unsigned int control_line_state;
static void *acm_data;
static int modem_open(struct inode *inode, struct file *file)
{
read_state = 0;
return 0;
}
static int modem_close(struct inode *inode, struct file *file)
{
return 0;
}
static ssize_t modem_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
int ret = 0;
if (file->f_flags & O_NONBLOCK)
return -EAGAIN;
ret = wait_event_interruptible(modem_wait_q, read_state);
if (ret)
return ret;
if (copy_to_user(buf, &control_line_state, sizeof(u32)))
return -EFAULT;
read_state = 0;
return sizeof(u32);
}
static unsigned int modem_poll(struct file *file, poll_table *wait)
{
int ret;
poll_wait(file, &modem_wait_q, wait);
ret = (read_state ? (POLLIN | POLLRDNORM) : 0);
return ret;
}
void notify_control_line_state(u32 value)
{
control_line_state = value;
read_state = 1;
wake_up_interruptible(&modem_wait_q);
}
EXPORT_SYMBOL(notify_control_line_state);
#define GS_CDC_NOTIFY_SERIAL_STATE _IOW('S', 1, int)
#define GS_IOC_NOTIFY_DTR_TEST _IOW('S', 3, int)
static long
modem_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
int ret = 0;
printk(KERN_INFO "modem_ioctl: cmd=0x%x, arg=%lu\n", cmd, arg);
/* handle ioctls */
switch (cmd) {
case GS_CDC_NOTIFY_SERIAL_STATE:
ret = acm_notify(acm_data, __constant_cpu_to_le16(arg));
return ret;
case GS_IOC_NOTIFY_DTR_TEST:
{
printk(KERN_ALERT"DUN : DTR %d\n", (int)arg);
notify_control_line_state((int)arg);
break;
}
default:
printk(KERN_INFO "modem_ioctl: Unknown ioctl cmd(0x%x).\n",
cmd);
return -ENOIOCTLCMD;
}
return 0;
}
static const struct file_operations modem_fops = {
.owner = THIS_MODULE,
.open = modem_open,
.release = modem_close,
.read = modem_read,
.poll = modem_poll,
.llseek = no_llseek,
.unlocked_ioctl = modem_ioctl,
};
static struct miscdevice modem_device = {
.minor = MISC_DYNAMIC_MINOR,
.name = "dun",
.fops = &modem_fops,
};
int modem_register(void *data)
{
if (data == NULL) {
printk(KERN_INFO "DUN register failed. data is null.\n");
return -1;
}
acm_data = data;
init_waitqueue_head(&modem_wait_q);
printk(KERN_INFO "DUN is registerd\n");
return 0;
}
EXPORT_SYMBOL(modem_register);
static int modem_misc_register(void)
{
int ret;
ret = misc_register(&modem_device);
if (ret) {
printk(KERN_ERR "DUN register is failed, ret = %d\n", ret);
return ret;
}
return ret;
}
void modem_unregister(void)
{
acm_data = NULL;
printk(KERN_INFO "DUN is unregisterd\n");
}
EXPORT_SYMBOL(modem_unregister);
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