linux/drivers/usb/serial/empeg.c
Alan Cox 335f8514f2 tty: Bring the usb tty port structure into more use
This allows us to clean stuff up, but is probably also going to cause
some app breakage with buggy apps as we now implement proper POSIX behaviour
for USB ports matching all the other ports. This does also mean other apps
that break on USB will now work properly.

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11 08:50:56 -07:00

565 lines
14 KiB
C

/*
* USB Empeg empeg-car player driver
*
* Copyright (C) 2000, 2001
* Gary Brubaker (xavyer@ix.netcom.com)
*
* Copyright (C) 1999 - 2001
* 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, as published by
* the Free Software Foundation, version 2.
*
* See Documentation/usb/usb-serial.txt for more information on using this
* driver
*
* (07/16/2001) gb
* remove unused code in empeg_close() (thanks to Oliver Neukum for
* pointing this out) and rewrote empeg_set_termios().
*
* (05/30/2001) gkh
* switched from using spinlock to a semaphore, which fixes lots of
* problems.
*
* (04/08/2001) gb
* Identify version on module load.
*
* (01/22/2001) gb
* Added write_room() and chars_in_buffer() support.
*
* (12/21/2000) gb
* Moved termio stuff inside the port->active check.
* Moved MOD_DEC_USE_COUNT to end of empeg_close().
*
* (12/03/2000) gb
* Added tty->ldisc.set_termios(port, tty, NULL) to empeg_open().
* This notifies the tty driver that the termios have changed.
*
* (11/13/2000) gb
* Moved tty->low_latency = 1 from empeg_read_bulk_callback() to
* empeg_open() (It only needs to be set once - Doh!)
*
* (11/11/2000) gb
* Updated to work with id_table structure.
*
* (11/04/2000) gb
* Forked this from visor.c, and hacked it up to work with an
* Empeg ltd. empeg-car player. Constructive criticism welcomed.
* I would like to say, 'Thank You' to Greg Kroah-Hartman for the
* use of his code, and for his guidance, advice and patience. :)
* A 'Thank You' is in order for John Ripley of Empeg ltd for his
* advice, and patience too.
*
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
static int debug;
/*
* Version Information
*/
#define DRIVER_VERSION "v1.2"
#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>, Gary Brubaker <xavyer@ix.netcom.com>"
#define DRIVER_DESC "USB Empeg Mark I/II Driver"
#define EMPEG_VENDOR_ID 0x084f
#define EMPEG_PRODUCT_ID 0x0001
/* function prototypes for an empeg-car player */
static int empeg_open(struct tty_struct *tty, struct usb_serial_port *port,
struct file *filp);
static void empeg_close(struct usb_serial_port *port);
static int empeg_write(struct tty_struct *tty, struct usb_serial_port *port,
const unsigned char *buf,
int count);
static int empeg_write_room(struct tty_struct *tty);
static int empeg_chars_in_buffer(struct tty_struct *tty);
static void empeg_throttle(struct tty_struct *tty);
static void empeg_unthrottle(struct tty_struct *tty);
static int empeg_startup(struct usb_serial *serial);
static void empeg_shutdown(struct usb_serial *serial);
static void empeg_set_termios(struct tty_struct *tty,
struct usb_serial_port *port, struct ktermios *old_termios);
static void empeg_write_bulk_callback(struct urb *urb);
static void empeg_read_bulk_callback(struct urb *urb);
static struct usb_device_id id_table [] = {
{ USB_DEVICE(EMPEG_VENDOR_ID, EMPEG_PRODUCT_ID) },
{ } /* Terminating entry */
};
MODULE_DEVICE_TABLE(usb, id_table);
static struct usb_driver empeg_driver = {
.name = "empeg",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = id_table,
.no_dynamic_id = 1,
};
static struct usb_serial_driver empeg_device = {
.driver = {
.owner = THIS_MODULE,
.name = "empeg",
},
.id_table = id_table,
.usb_driver = &empeg_driver,
.num_ports = 1,
.open = empeg_open,
.close = empeg_close,
.throttle = empeg_throttle,
.unthrottle = empeg_unthrottle,
.attach = empeg_startup,
.shutdown = empeg_shutdown,
.set_termios = empeg_set_termios,
.write = empeg_write,
.write_room = empeg_write_room,
.chars_in_buffer = empeg_chars_in_buffer,
.write_bulk_callback = empeg_write_bulk_callback,
.read_bulk_callback = empeg_read_bulk_callback,
};
#define NUM_URBS 16
#define URB_TRANSFER_BUFFER_SIZE 4096
static struct urb *write_urb_pool[NUM_URBS];
static spinlock_t write_urb_pool_lock;
static int bytes_in;
static int bytes_out;
/******************************************************************************
* Empeg specific driver functions
******************************************************************************/
static int empeg_open(struct tty_struct *tty, struct usb_serial_port *port,
struct file *filp)
{
struct usb_serial *serial = port->serial;
int result = 0;
dbg("%s - port %d", __func__, port->number);
/* Force default termio settings */
empeg_set_termios(tty, port, NULL) ;
bytes_in = 0;
bytes_out = 0;
/* 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,
empeg_read_bulk_callback,
port);
result = usb_submit_urb(port->read_urb, GFP_KERNEL);
if (result)
dev_err(&port->dev,
"%s - failed submitting read urb, error %d\n",
__func__, result);
return result;
}
static void empeg_close(struct usb_serial_port *port)
{
dbg("%s - port %d", __func__, port->number);
/* shutdown our bulk read */
usb_kill_urb(port->read_urb);
/* Uncomment the following line if you want to see some statistics in your syslog */
/* dev_info (&port->dev, "Bytes In = %d Bytes Out = %d\n", bytes_in, bytes_out); */
}
static int empeg_write(struct tty_struct *tty, struct usb_serial_port *port,
const unsigned char *buf, int count)
{
struct usb_serial *serial = port->serial;
struct urb *urb;
const unsigned char *current_position = buf;
unsigned long flags;
int status;
int i;
int bytes_sent = 0;
int transfer_size;
dbg("%s - port %d", __func__, port->number);
while (count > 0) {
/* try to find a free urb in our list of them */
urb = NULL;
spin_lock_irqsave(&write_urb_pool_lock, flags);
for (i = 0; i < NUM_URBS; ++i) {
if (write_urb_pool[i]->status != -EINPROGRESS) {
urb = write_urb_pool[i];
break;
}
}
spin_unlock_irqrestore(&write_urb_pool_lock, flags);
if (urb == NULL) {
dbg("%s - no more free urbs", __func__);
goto exit;
}
if (urb->transfer_buffer == NULL) {
urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
if (urb->transfer_buffer == NULL) {
dev_err(&port->dev,
"%s no more kernel memory...\n",
__func__);
goto exit;
}
}
transfer_size = min(count, URB_TRANSFER_BUFFER_SIZE);
memcpy(urb->transfer_buffer, current_position, transfer_size);
usb_serial_debug_data(debug, &port->dev, __func__, transfer_size, urb->transfer_buffer);
/* build up our urb */
usb_fill_bulk_urb(
urb,
serial->dev,
usb_sndbulkpipe(serial->dev,
port->bulk_out_endpointAddress),
urb->transfer_buffer,
transfer_size,
empeg_write_bulk_callback,
port);
/* send it down the pipe */
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status) {
dev_err(&port->dev, "%s - usb_submit_urb(write bulk) failed with status = %d\n", __func__, status);
bytes_sent = status;
break;
}
current_position += transfer_size;
bytes_sent += transfer_size;
count -= transfer_size;
bytes_out += transfer_size;
}
exit:
return bytes_sent;
}
static int empeg_write_room(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
unsigned long flags;
int i;
int room = 0;
dbg("%s - port %d", __func__, port->number);
spin_lock_irqsave(&write_urb_pool_lock, flags);
/* tally up the number of bytes available */
for (i = 0; i < NUM_URBS; ++i) {
if (write_urb_pool[i]->status != -EINPROGRESS)
room += URB_TRANSFER_BUFFER_SIZE;
}
spin_unlock_irqrestore(&write_urb_pool_lock, flags);
dbg("%s - returns %d", __func__, room);
return room;
}
static int empeg_chars_in_buffer(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
unsigned long flags;
int i;
int chars = 0;
dbg("%s - port %d", __func__, port->number);
spin_lock_irqsave(&write_urb_pool_lock, flags);
/* tally up the number of bytes waiting */
for (i = 0; i < NUM_URBS; ++i) {
if (write_urb_pool[i]->status == -EINPROGRESS)
chars += URB_TRANSFER_BUFFER_SIZE;
}
spin_unlock_irqrestore(&write_urb_pool_lock, flags);
dbg("%s - returns %d", __func__, chars);
return chars;
}
static void empeg_write_bulk_callback(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
int status = urb->status;
dbg("%s - port %d", __func__, port->number);
if (status) {
dbg("%s - nonzero write bulk status received: %d",
__func__, status);
return;
}
usb_serial_port_softint(port);
}
static void empeg_read_bulk_callback(struct urb *urb)
{
struct usb_serial_port *port = urb->context;
struct tty_struct *tty;
unsigned char *data = urb->transfer_buffer;
int result;
int status = urb->status;
dbg("%s - port %d", __func__, port->number);
if (status) {
dbg("%s - nonzero read bulk status received: %d",
__func__, status);
return;
}
usb_serial_debug_data(debug, &port->dev, __func__,
urb->actual_length, data);
tty = tty_port_tty_get(&port->port);
if (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);
bytes_in += urb->actual_length;
}
tty_kref_put(tty);
/* Continue trying to always read */
usb_fill_bulk_urb(
port->read_urb,
port->serial->dev,
usb_rcvbulkpipe(port->serial->dev,
port->bulk_in_endpointAddress),
port->read_urb->transfer_buffer,
port->read_urb->transfer_buffer_length,
empeg_read_bulk_callback,
port);
result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
if (result)
dev_err(&urb->dev->dev,
"%s - failed resubmitting read urb, error %d\n",
__func__, result);
return;
}
static void empeg_throttle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
usb_kill_urb(port->read_urb);
}
static void empeg_unthrottle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
int result;
dbg("%s - port %d", __func__, port->number);
port->read_urb->dev = port->serial->dev;
result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
if (result)
dev_err(&port->dev,
"%s - failed submitting read urb, error %d\n",
__func__, result);
}
static int empeg_startup(struct usb_serial *serial)
{
int r;
dbg("%s", __func__);
if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
dev_err(&serial->dev->dev, "active config #%d != 1 ??\n",
serial->dev->actconfig->desc.bConfigurationValue);
return -ENODEV;
}
dbg("%s - reset config", __func__);
r = usb_reset_configuration(serial->dev);
/* continue on with initialization */
return r;
}
static void empeg_shutdown(struct usb_serial *serial)
{
dbg("%s", __func__);
}
static void empeg_set_termios(struct tty_struct *tty,
struct usb_serial_port *port, struct ktermios *old_termios)
{
struct ktermios *termios = tty->termios;
dbg("%s - port %d", __func__, port->number);
/*
* The empeg-car player wants these particular tty settings.
* You could, for example, change the baud rate, however the
* player only supports 115200 (currently), so there is really
* no point in support for changes to the tty settings.
* (at least for now)
*
* The default requirements for this device are:
*/
termios->c_iflag
&= ~(IGNBRK /* disable ignore break */
| BRKINT /* disable break causes interrupt */
| PARMRK /* disable mark parity errors */
| ISTRIP /* disable clear high bit of input characters */
| INLCR /* disable translate NL to CR */
| IGNCR /* disable ignore CR */
| ICRNL /* disable translate CR to NL */
| IXON); /* disable enable XON/XOFF flow control */
termios->c_oflag
&= ~OPOST; /* disable postprocess output characters */
termios->c_lflag
&= ~(ECHO /* disable echo input characters */
| ECHONL /* disable echo new line */
| ICANON /* disable erase, kill, werase, and rprnt special characters */
| ISIG /* disable interrupt, quit, and suspend special characters */
| IEXTEN); /* disable non-POSIX special characters */
termios->c_cflag
&= ~(CSIZE /* no size */
| PARENB /* disable parity bit */
| CBAUD); /* clear current baud rate */
termios->c_cflag
|= CS8; /* character size 8 bits */
tty_encode_baud_rate(tty, 115200, 115200);
}
static int __init empeg_init(void)
{
struct urb *urb;
int i, retval;
/* create our write urb pool and transfer buffers */
spin_lock_init(&write_urb_pool_lock);
for (i = 0; i < NUM_URBS; ++i) {
urb = usb_alloc_urb(0, GFP_KERNEL);
write_urb_pool[i] = urb;
if (urb == NULL) {
printk(KERN_ERR "empeg: No more urbs???\n");
continue;
}
urb->transfer_buffer = kmalloc(URB_TRANSFER_BUFFER_SIZE,
GFP_KERNEL);
if (!urb->transfer_buffer) {
printk(KERN_ERR "empeg: %s - out of memory for urb "
"buffers.", __func__);
continue;
}
}
retval = usb_serial_register(&empeg_device);
if (retval)
goto failed_usb_serial_register;
retval = usb_register(&empeg_driver);
if (retval)
goto failed_usb_register;
printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
DRIVER_DESC "\n");
return 0;
failed_usb_register:
usb_serial_deregister(&empeg_device);
failed_usb_serial_register:
for (i = 0; i < NUM_URBS; ++i) {
if (write_urb_pool[i]) {
kfree(write_urb_pool[i]->transfer_buffer);
usb_free_urb(write_urb_pool[i]);
}
}
return retval;
}
static void __exit empeg_exit(void)
{
int i;
unsigned long flags;
usb_deregister(&empeg_driver);
usb_serial_deregister(&empeg_device);
spin_lock_irqsave(&write_urb_pool_lock, flags);
for (i = 0; i < NUM_URBS; ++i) {
if (write_urb_pool[i]) {
/* FIXME - uncomment the following usb_kill_urb call
* when the host controllers get fixed to set urb->dev
* = NULL after the urb is finished. Otherwise this
* call oopses. */
/* usb_kill_urb(write_urb_pool[i]); */
kfree(write_urb_pool[i]->transfer_buffer);
usb_free_urb(write_urb_pool[i]);
}
}
spin_unlock_irqrestore(&write_urb_pool_lock, flags);
}
module_init(empeg_init);
module_exit(empeg_exit);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");