/*
* USB Serial Converter Generic functions
*
* Copyright (C) 1999 - 2002 Greg Kroah-Hartman (greg@kroah.com)
*
* 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.
*
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/uaccess.h>
static int debug;
#ifdef CONFIG_USB_SERIAL_GENERIC
static int generic_probe(struct usb_interface *interface,
const struct usb_device_id *id);
static __u16 vendor = 0x05f9;
static __u16 product = 0xffff;
module_param(vendor, ushort, 0);
MODULE_PARM_DESC(vendor, "User specified USB idVendor");
module_param(product, ushort, 0);
MODULE_PARM_DESC(product, "User specified USB idProduct");
static struct usb_device_id generic_device_ids[2]; /* Initially all zeroes. */
/* we want to look at all devices, as the vendor/product id can change
* depending on the command line argument */
static struct usb_device_id generic_serial_ids[] = {
{.driver_info = 42},
{}
};
static struct usb_driver generic_driver = {
.name = "usbserial_generic",
.probe = generic_probe,
.disconnect = usb_serial_disconnect,
.id_table = generic_serial_ids,
.no_dynamic_id = 1,
};
/* All of the device info needed for the Generic Serial Converter */
struct usb_serial_driver usb_serial_generic_device = {
.driver = {
.owner = THIS_MODULE,
.name = "generic",
},
.id_table = generic_device_ids,
.usb_driver = &generic_driver,
.num_ports = 1,
.shutdown = usb_serial_generic_shutdown,
.throttle = usb_serial_generic_throttle,
.unthrottle = usb_serial_generic_unthrottle,
.resume = usb_serial_generic_resume,
};
static int generic_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
const struct usb_device_id *id_pattern;
id_pattern = usb_match_id(interface, generic_device_ids);
if (id_pattern != NULL)
return usb_serial_probe(interface, id);
return -ENODEV;
}
#endif
int usb_serial_generic_register(int _debug)
{
int retval = 0;
debug = _debug;
#ifdef CONFIG_USB_SERIAL_GENERIC
generic_device_ids[0].idVendor = vendor;
generic_device_ids[0].idProduct = product;
generic_device_ids[0].match_flags =
USB_DEVICE_ID_MATCH_VENDOR | USB_DEVICE_ID_MATCH_PRODUCT;
/* register our generic driver with ourselves */
retval = usb_serial_register(&usb_serial_generic_device);
if (retval)
goto exit;
retval = usb_register(&generic_driver);
if (retval)
usb_serial_deregister(&usb_serial_generic_device);
exit:
#endif
return retval;
}
void usb_serial_generic_deregister(void)
{
#ifdef CONFIG_USB_SERIAL_GENERIC
/* remove our generic driver */
usb_deregister(&generic_driver);
usb_serial_deregister(&usb_serial_generic_device);
#endif
}
int usb_serial_generic_open(struct tty_struct *tty,
struct usb_serial_port *port, struct file *filp)
{
struct usb_serial *serial = port->serial;
int result = 0;
unsigned long flags;
dbg("%s - port %d", __func__, port->number);
/* force low_latency on so that our tty_push actually forces the data
through, otherwise it is scheduled, and with high data rates (like
with OHCI) data can get lost. */
if (tty)
tty->low_latency = 1;
/* clear the throttle flags */
spin_lock_irqsave(&port->lock, flags);
port->throttled = 0;
port->throttle_req = 0;
spin_unlock_irqrestore(&port->lock, flags);
/* if we have a bulk endpoint, start reading from it */
if (serial->num_bulk_in) {
/* Start reading from the device */
usb_fill_bulk_urb(port->read_urb, serial->dev,
usb_rcvbulkpipe(serial->dev,
port->bulk_in_endpointAddress),
port->read_urb->transfer_buffer,
port->read_urb->transfer_buffer_length,
((serial->type->read_bulk_callback) ?
serial->type->read_bulk_callback :
usb_serial_generic_read_bulk_callback),
port);
result = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (result)
dev_err(&port->dev,
"%s - failed resubmitting read urb, error %d\n",
__func__, result);
}
return result;
}
EXPORT_SYMBOL_GPL(usb_serial_generic_open);
static void generic_cleanup(struct usb_serial_port *port)
{
struct usb_serial *serial = port->serial;
dbg("%s - port %d", __func__, port->number);
if (serial->dev) {
/* shutdown any bulk reads that might be going on */
if (serial->num_bulk_out)
usb_kill_urb(port->write_urb);
if (serial->num_bulk_in)
usb_kill_urb(port->read_urb);
}
}
int usb_serial_generic_resume(struct usb_serial *serial)
{
struct usb_serial_port *port;
int i, c = 0, r;
for (i = 0; i < serial->num_ports; i++) {
port = serial->port[i];
if (port->port.count && port->read_urb) {
r = usb_submit_urb(port->read_urb, GFP_NOIO);
if (r < 0)
c++;
}
}
return c ? -EIO : 0;
}
EXPORT_SYMBOL_GPL(usb_serial_generic_resume);
void usb_serial_generic_close(struct tty_struct *tty,
struct usb_serial_port *port, struct file *filp)
{
dbg("%s - port %d", __func__, port->number);
generic_cleanup(port);
}
int usb_serial_generic_write(struct tty_struct *tty,
struct usb_serial_port *port, const unsigned char *buf, int count)
{
struct usb_serial *serial = port->serial;
int result;
unsigned char *data;
dbg("%s - port %d", __func__, port->number);
if (count == 0) {
dbg("%s - write request of 0 bytes", __func__);
return 0;
}
/* only do something if we have a bulk out endpoint */
if (serial->num_bulk_out) {
unsigned long flags;
spin_lock_irqsave(&port->lock, flags);
if (port->write_urb_busy) {
spin_unlock_irqrestore(&port->lock, flags);
dbg("%s - already writing", __func__);
return 0;
}
port->write_urb_busy = 1;
spin_unlock_irqrestore(&port->lock, flags);
count = (count > port->bulk_out_size) ?
port->bulk_out_size : count;
memcpy(port->write_urb->transfer_buffer, buf, count);
data = port->write_urb->transfer_buffer;
usb_serial_debug_data(debug, &port->dev, __func__, count, data);
/* set up our urb */
usb_fill_bulk_urb(port->write_urb, serial->dev,
usb_sndbulkpipe(serial->dev,
port->bulk_out_endpointAddress),
port->write_urb->transfer_buffer, count,
((serial->type->write_bulk_callback) ?
serial->type->write_bulk_callback :
usb_serial_generic_write_bulk_callback),
port);
/* send the data out the bulk port */
port->write_urb_busy = 1;
result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
if (result) {
dev_err(&port->dev,
"%s - failed submitting write urb, error %d\n",
__func__, result);
/* don't have to grab the lock here, as we will
retry if != 0 */
port->write_urb_busy = 0;
} else
result = count;
return result;
}
/* no bulk out, so return 0 bytes written */
return 0;
}
int usb_serial_generic_write_room(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct usb_serial *serial = port->serial;
int room = 0;
dbg("%s - port %d", __func__, port->number);
/* FIXME: Locking */
if (serial->num_bulk_out) {
if (!(port->write_urb_busy))
room = port->bulk_out_size;
}
dbg("%s - returns %d", __func__, room);
return room;
}
int usb_serial_generic_chars_in_buffer(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct usb_serial *serial = port->serial;
int chars = 0;
dbg("%s - port %d", __func__, port->number);
/* FIXME: Locking */
if (serial->num_bulk_out) {
if (port->write_urb_busy)
chars = port->write_urb->transfer_buffer_length;
}
dbg("%s - returns %d", __func__, chars);
return chars;
}
static void resubmit_read_urb(struct usb_serial_port *port, gfp_t mem_flags)
{
struct urb *urb = port->read_urb;
struct usb_serial *serial = port->serial;
int result;
/* Continue reading from device */
usb_fill_bulk_urb(urb, serial->dev,
usb_rcvbulkpipe(serial->dev,
port->bulk_in_endpointAddress),
urb->transfer_buffer,
urb->transfer_buffer_length,
((serial->type->read_bulk_callback) ?
serial->type->read_bulk_callback :
usb_serial_generic_read_bulk_callback), port);
result = usb_submit_urb(urb, mem_flags);
if (result)
dev_err(&port->dev,
"%s - failed resubmitting read urb, error %d\n",
__func__, result);
}
/* Push data to tty layer and resubmit the bulk read URB */
static void flush_and_resubmit_read_urb(struct usb_serial_port *port)
{
struct urb *urb = port->read_urb;
struct tty_struct *tty = tty_port_tty_get(&port->port);
int room;
/* Push data to tty */
if (tty && urb->actual_length) {
room = tty_buffer_request_room(tty, urb->actual_length);
if (room) {
tty_insert_flip_string(tty, urb->transfer_buffer, room);
tty_flip_buffer_push(tty);
}
}
tty_kref_put(tty);
resubmit_read_urb(port, GFP_ATOMIC);
}
void usb_serial_generic_read_bulk_callback(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
unsigned char *data = urb->transfer_buffer;
int status = urb->status;
unsigned long flags;
dbg("%s - port %d", __func__, port->number);
if (unlikely(status != 0)) {
dbg("%s - nonzero read bulk status received: %d",
__func__, status);
return;
}
usb_serial_debug_data(debug, &port->dev, __func__,
urb->actual_length, data);
/* Throttle the device if requested by tty */
spin_lock_irqsave(&port->lock, flags);
port->throttled = port->throttle_req;
if (!port->throttled) {
spin_unlock_irqrestore(&port->lock, flags);
flush_and_resubmit_read_urb(port);
} else
spin_unlock_irqrestore(&port->lock, flags);
}
EXPORT_SYMBOL_GPL(usb_serial_generic_read_bulk_callback);
void usb_serial_generic_write_bulk_callback(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
int status = urb->status;
dbg("%s - port %d", __func__, port->number);
port->write_urb_busy = 0;
if (status) {
dbg("%s - nonzero write bulk status received: %d",
__func__, status);
return;
}
usb_serial_port_softint(port);
}
EXPORT_SYMBOL_GPL(usb_serial_generic_write_bulk_callback);
void usb_serial_generic_throttle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
unsigned long flags;
dbg("%s - port %d", __func__, port->number);
/* Set the throttle request flag. It will be picked up
* by usb_serial_generic_read_bulk_callback(). */
spin_lock_irqsave(&port->lock, flags);
port->throttle_req = 1;
spin_unlock_irqrestore(&port->lock, flags);
}
void usb_serial_generic_unthrottle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
int was_throttled;
unsigned long flags;
dbg("%s - port %d", __func__, port->number);
/* Clear the throttle flags */
spin_lock_irqsave(&port->lock, flags);
was_throttled = port->throttled;
port->throttled = port->throttle_req = 0;
spin_unlock_irqrestore(&port->lock, flags);
if (was_throttled) {
/* Resume reading from device */
resubmit_read_urb(port, GFP_KERNEL);
}
}
void usb_serial_generic_shutdown(struct usb_serial *serial)
{
int i;
dbg("%s", __func__);
/* stop reads and writes on all ports */
for (i = 0; i < serial->num_ports; ++i)
generic_cleanup(serial->port[i]);
}
