linux-stable/drivers/usb/serial/navman.c
Alan Cox 4a90f09b20 tty: usb-serial krefs
Use kref in the USB serial drivers so that we don't free tty structures
from under the URB receive handlers as has historically been the case if
you were unlucky. This also gives us a framework for general tty drivers to
use tty_port objects and refcount.

Contains two err->dev_err changes merged together to fix clashes in the
-next tree.

Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-13 09:51:41 -07:00

158 lines
3.6 KiB
C

/*
* Navman Serial USB driver
*
* Copyright (C) 2006 Greg Kroah-Hartman <gregkh@suse.de>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* TODO:
* Add termios method that uses copy_hw but also kills all echo
* flags as the navman is rx only so cannot echo.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
static int debug;
static struct usb_device_id id_table [] = {
{ USB_DEVICE(0x0a99, 0x0001) }, /* Talon Technology device */
{ },
};
MODULE_DEVICE_TABLE(usb, id_table);
static struct usb_driver navman_driver = {
.name = "navman",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = id_table,
.no_dynamic_id = 1,
};
static void navman_read_int_callback(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
unsigned char *data = urb->transfer_buffer;
struct tty_struct *tty;
int status = urb->status;
int result;
switch (status) {
case 0:
/* success */
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
dbg("%s - urb shutting down with status: %d",
__func__, status);
return;
default:
dbg("%s - nonzero urb status received: %d",
__func__, status);
goto exit;
}
usb_serial_debug_data(debug, &port->dev, __func__,
urb->actual_length, data);
tty = tty_port_tty_get(&port->port);
if (tty && urb->actual_length) {
tty_buffer_request_room(tty, urb->actual_length);
tty_insert_flip_string(tty, data, urb->actual_length);
tty_flip_buffer_push(tty);
}
tty_kref_put(tty);
exit:
result = usb_submit_urb(urb, GFP_ATOMIC);
if (result)
dev_err(&urb->dev->dev,
"%s - Error %d submitting interrupt urb\n",
__func__, result);
}
static int navman_open(struct tty_struct *tty,
struct usb_serial_port *port, struct file *filp)
{
int result = 0;
dbg("%s - port %d", __func__, port->number);
if (port->interrupt_in_urb) {
dbg("%s - adding interrupt input for treo", __func__);
result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
if (result)
dev_err(&port->dev,
"%s - failed submitting interrupt urb, error %d\n",
__func__, result);
}
return result;
}
static void navman_close(struct tty_struct *tty,
struct usb_serial_port *port, struct file *filp)
{
dbg("%s - port %d", __func__, port->number);
usb_kill_urb(port->interrupt_in_urb);
}
static int navman_write(struct tty_struct *tty, struct usb_serial_port *port,
const unsigned char *buf, int count)
{
dbg("%s - port %d", __func__, port->number);
/*
* This device can't write any data, only read from the device
*/
return -EOPNOTSUPP;
}
static struct usb_serial_driver navman_device = {
.driver = {
.owner = THIS_MODULE,
.name = "navman",
},
.id_table = id_table,
.usb_driver = &navman_driver,
.num_ports = 1,
.open = navman_open,
.close = navman_close,
.write = navman_write,
.read_int_callback = navman_read_int_callback,
};
static int __init navman_init(void)
{
int retval;
retval = usb_serial_register(&navman_device);
if (retval)
return retval;
retval = usb_register(&navman_driver);
if (retval)
usb_serial_deregister(&navman_device);
return retval;
}
static void __exit navman_exit(void)
{
usb_deregister(&navman_driver);
usb_serial_deregister(&navman_device);
}
module_init(navman_init);
module_exit(navman_exit);
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");