/*
* 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 tty_struct *tty, struct usb_serial_port *port,
struct file *filp);
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 tty_struct *tty, struct usb_serial_port *port,
struct file *filp)
{
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 */
/*
* Force low_latency on; otherwise the pushes are scheduled;
* this is bad as it opens up the possibility of dropping bytes
* on the floor. We don't want to drop bytes on the floor. :)
*/
tty->low_latency = 1;
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");
