- 根目录:
- drivers
- usb
- serial
- opticon.c
/*
* Opticon USB barcode to serial driver
*
* Copyright (C) 2011 Martin Jansen <martin.jansen@opticon.com>
* Copyright (C) 2008 - 2009 Greg Kroah-Hartman <gregkh@suse.de>
* Copyright (C) 2008 - 2009 Novell Inc.
*
* 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/init.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/slab.h>
#include <linux/tty_flip.h>
#include <linux/serial.h>
#include <linux/module.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/uaccess.h>
#define CONTROL_RTS 0x02
#define RESEND_CTS_STATE 0x03
/* max number of write urbs in flight */
#define URB_UPPER_LIMIT 8
/* This driver works for the Opticon 1D barcode reader
* an examples of 1D barcode types are EAN, UPC, Code39, IATA etc.. */
#define DRIVER_DESC "Opticon USB barcode to serial driver (1D)"
static int debug;
static const struct usb_device_id id_table[] = {
{ USB_DEVICE(0x065a, 0x0009) },
{ },
};
MODULE_DEVICE_TABLE(usb, id_table);
/* This structure holds all of the individual device information */
struct opticon_private {
struct usb_device *udev;
struct usb_serial *serial;
struct usb_serial_port *port;
unsigned char *bulk_in_buffer;
struct urb *bulk_read_urb;
int buffer_size;
u8 bulk_address;
spinlock_t lock; /* protects the following flags */
bool throttled;
bool actually_throttled;
bool rts;
bool cts;
int outstanding_urbs;
};
static void opticon_read_bulk_callback(struct urb *urb)
{
struct opticon_private *priv = urb->context;
unsigned char *data = urb->transfer_buffer;
struct usb_serial_port *port = priv->port;
int status = urb->status;
struct tty_struct *tty;
int result;
int data_length;
unsigned long flags;
dbg("%s - port %d", __func__, port->number);
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);
if (urb->actual_length > 2) {
data_length = urb->actual_length - 2;
/*
* Data from the device comes with a 2 byte header:
*
* <0x00><0x00>data...
* This is real data to be sent to the tty layer
* <0x00><0x01)level
* This is a CTS level change, the third byte is the CTS
* value (0 for low, 1 for high).
*/
if ((data[0] == 0x00) && (data[1] == 0x00)) {
/* real data, send it to the tty layer */
tty = tty_port_tty_get(&port->port);
if (tty) {
tty_insert_flip_string(tty, data + 2,
data_length);
tty_flip_buffer_push(tty);
tty_kref_put(tty);
}
} else {
if ((data[0] == 0x00) && (data[1] == 0x01)) {
spin_lock_irqsave(&priv->lock, flags);
/* CTS status information package */
if (data[2] == 0x00)
priv->cts = false;
else
priv->cts = true;
spin_unlock_irqrestore(&priv->lock, flags);
} else {
dev_dbg(&priv->udev->dev,
"Unknown data packet received from the device:"
" %2x %2x\n",
data[0], data[1]);
}
}
} else {
dev_dbg(&priv->udev->dev,
"Improper amount of data received from the device, "
"%d bytes", urb->actual_length);
}
exit:
spin_lock(&priv->lock);
/* Continue trying to always read if we should */
if (!priv->throttled) {
usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev,
usb_rcvbulkpipe(priv->udev,
priv->bulk_address),
priv->bulk_in_buffer, priv->buffer_size,
opticon_read_bulk_callback, priv);
result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC);
if (result)
dev_err(&port->dev,
"%s - failed resubmitting read urb, error %d\n",
__func__, result);
} else
priv->actually_throttled = true;
spin_unlock(&priv->lock);
}
static int send_control_msg(struct usb_serial_port *port, u8 requesttype,
u8 val)
{
struct usb_serial *serial = port->serial;
int retval;
u8 buffer[2];
buffer[0] = val;
/* Send the message to the vendor control endpoint
* of the connected device */
retval = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
requesttype,
USB_DIR_OUT|USB_TYPE_VENDOR|USB_RECIP_INTERFACE,
0, 0, buffer, 1, 0);
return retval;
}
static int opticon_open(struct tty_struct *tty, struct usb_serial_port *port)
{
struct opticon_private *priv = usb_get_serial_data(port->serial);
unsigned long flags;
int result = 0;
dbg("%s - port %d", __func__, port->number);
spin_lock_irqsave(&priv->lock, flags);
priv->throttled = false;
priv->actually_throttled = false;
priv->port = port;
priv->rts = false;
spin_unlock_irqrestore(&priv->lock, flags);
/* Clear RTS line */
send_control_msg(port, CONTROL_RTS, 0);
/* Setup the read URB and start reading from the device */
usb_fill_bulk_urb(priv->bulk_read_urb, priv->udev,
usb_rcvbulkpipe(priv->udev,
priv->bulk_address),
priv->bulk_in_buffer, priv->buffer_size,
opticon_read_bulk_callback, priv);
/* clear the halt status of the enpoint */
usb_clear_halt(priv->udev, priv->bulk_read_urb->pipe);
result = usb_submit_urb(priv->bulk_read_urb, GFP_KERNEL);
if (result)
dev_err(&port->dev,
"%s - failed resubmitting read urb, error %d\n",
__func__, result);
/* Request CTS line state, sometimes during opening the current
* CTS state can be missed. */
send_control_msg(port, RESEND_CTS_STATE, 1);
return result;
}
static void opticon_close(struct usb_serial_port *port)
{
struct opticon_private *priv = usb_get_serial_data(port->serial);
dbg("%s - port %d", __func__, port->number);
/* shutdown our urbs */
usb_kill_urb(priv->bulk_read_urb);
}
static void opticon_write_control_callback(struct urb *urb)
{
struct opticon_private *priv = urb->context;
int status = urb->status;
unsigned long flags;
/* free up the transfer buffer, as usb_free_urb() does not do this */
kfree(urb->transfer_buffer);
/* setup packet may be set if we're using it for writing */
kfree(urb->setup_packet);
if (status)
dbg("%s - nonzero write bulk status received: %d",
__func__, status);
spin_lock_irqsave(&priv->lock, flags);
--priv->outstanding_urbs;
spin_unlock_irqrestore(&priv->lock, flags);
usb_serial_port_softint(priv->port);
}
static int opticon_write(struct tty_struct *tty, struct usb_serial_port *port,
const unsigned char *buf, int count)
{
struct opticon_private *priv = usb_get_serial_data(port->serial);
struct usb_serial *serial = port->serial;
struct urb *urb;
unsigned char *buffer;
unsigned long flags;
int status;
struct usb_ctrlrequest *dr;
dbg("%s - port %d", __func__, port->number);
spin_lock_irqsave(&priv->lock, flags);
if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
spin_unlock_irqrestore(&priv->lock, flags);
dbg("%s - write limit hit", __func__);
return 0;
}
priv->outstanding_urbs++;
spin_unlock_irqrestore(&priv->lock, flags);
buffer = kmalloc(count, GFP_ATOMIC);
if (!buffer) {
dev_err(&port->dev, "out of memory\n");
count = -ENOMEM;
goto error_no_buffer;
}
urb = usb_alloc_urb(0, GFP_ATOMIC);
if (!urb) {
dev_err(&port->dev, "no more free urbs\n");
count = -ENOMEM;
goto error_no_urb;
}
memcpy(buffer, buf, count);
usb_serial_debug_data(debug, &port->dev, __func__, count, buffer);
/* The conncected devices do not have a bulk write endpoint,
* to transmit data to de barcode device the control endpoint is used */
dr = kmalloc(sizeof(struct usb_ctrlrequest), GFP_NOIO);
if (!dr)
return -ENOMEM;
dr->bRequestType = USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT;
dr->bRequest = 0x01;
dr->wValue = 0;
dr->wIndex = 0;
dr->wLength = cpu_to_le16(count);
usb_fill_control_urb(urb, serial->dev,
usb_sndctrlpipe(serial->dev, 0),
(unsigned char *)dr, buffer, count,
opticon_write_control_callback, priv);
/* send it down the pipe */
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status) {
dev_err(&port->dev,
"%s - usb_submit_urb(write endpoint) failed status = %d\n",
__func__, status);
count = status;
goto error;
}
/* we are done with this urb, so let the host driver
* really free it when it is finished with it */
usb_free_urb(urb);
return count;
error:
usb_free_urb(urb);
error_no_urb:
kfree(buffer);
error_no_buffer:
spin_lock_irqsave(&priv->lock, flags);
--priv->outstanding_urbs;
spin_unlock_irqrestore(&priv->lock, flags);
return count;
}
static int opticon_write_room(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct opticon_private *priv = usb_get_serial_data(port->serial);
unsigned long flags;
dbg("%s - port %d", __func__, port->number);
/*
* We really can take almost anything the user throws at us
* but let's pick a nice big number to tell the tty
* layer that we have lots of free space, unless we don't.
*/
spin_lock_irqsave(&priv->lock, flags);
if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) {
spin_unlock_irqrestore(&priv->lock, flags);
dbg("%s - write limit hit", __func__);
return 0;
}
spin_unlock_irqrestore(&priv->lock, flags);
return 2048;
}
static void opticon_throttle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct opticon_private *priv = usb_get_serial_data(port->serial);
unsigned long flags;
dbg("%s - port %d", __func__, port->number);
spin_lock_irqsave(&priv->lock, flags);
priv->throttled = true;
spin_unlock_irqrestore(&priv->lock, flags);
}
static void opticon_unthrottle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct opticon_private *priv = usb_get_serial_data(port->serial);
unsigned long flags;
int result, was_throttled;
dbg("%s - port %d", __func__, port->number);
spin_lock_irqsave(&priv->lock, flags);
priv->throttled = false;
was_throttled = priv->actually_throttled;
priv->actually_throttled = false;
spin_unlock_irqrestore(&priv->lock, flags);
priv->bulk_read_urb->dev = port->serial->dev;
if (was_throttled) {
result = usb_submit_urb(priv->bulk_read_urb, GFP_ATOMIC);
if (result)
dev_err(&port->dev,
"%s - failed submitting read urb, error %d\n",
__func__, result);
}
}
static int opticon_tiocmget(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct opticon_private *priv = usb_get_serial_data(port->serial);
unsigned long flags;
int result = 0;
dbg("%s - port %d", __func__, port->number);
if (!usb_get_intfdata(port->serial->interface))
return -ENODEV;
spin_lock_irqsave(&priv->lock, flags);
if (priv->rts)
result |= TIOCM_RTS;
if (priv->cts)
result |= TIOCM_CTS;
spin_unlock_irqrestore(&priv->lock, flags);
dbg("%s - %x", __func__, result);
return result;
}
static int opticon_tiocmset(struct tty_struct *tty,
unsigned int set, unsigned int clear)
{
struct usb_serial_port *port = tty->driver_data;
struct opticon_private *priv = usb_get_serial_data(port->serial);
unsigned long flags;
bool rts;
bool changed = false;
if (!usb_get_intfdata(port->serial->interface))
return -ENODEV;
/* We only support RTS so we only handle that */
spin_lock_irqsave(&priv->lock, flags);
rts = priv->rts;
if (set & TIOCM_RTS)
priv->rts = true;
if (clear & TIOCM_RTS)
priv->rts = false;
changed = rts ^ priv->rts;
spin_unlock_irqrestore(&priv->lock, flags);
if (!changed)
return 0;
/* Send the new RTS state to the connected device */
return send_control_msg(port, CONTROL_RTS, !rts);
}
static int get_serial_info(struct opticon_private *priv,
struct serial_struct __user *serial)
{
struct serial_struct tmp;
if (!serial)
return -EFAULT;
memset(&tmp, 0x00, sizeof(tmp));
/* fake emulate a 16550 uart to make userspace code happy */
tmp.type = PORT_16550A;
tmp.line = priv->serial->minor;
tmp.port = 0;
tmp.irq = 0;
tmp.flags = ASYNC_SKIP_TEST | ASYNC_AUTO_IRQ;
tmp.xmit_fifo_size = 1024;
tmp.baud_base = 9600;
tmp.close_delay = 5*HZ;
tmp.closing_wait = 30*HZ;
if (copy_to_user(serial, &tmp, sizeof(*serial)))
return -EFAULT;
return 0;
}
static int opticon_ioctl(struct tty_struct *tty,
unsigned int cmd, unsigned long arg)
{
struct usb_serial_port *port = tty->driver_data;
struct opticon_private *priv = usb_get_serial_data(port->serial);
dbg("%s - port %d, cmd = 0x%x", __func__, port->number, cmd);
switch (cmd) {
case TIOCGSERIAL:
return get_serial_info(priv,
(struct serial_struct __user *)arg);
}
return -ENOIOCTLCMD;
}
static int opticon_startup(struct usb_serial *serial)
{
struct opticon_private *priv;
struct usb_host_interface *intf;
int i;
int retval = -ENOMEM;
bool bulk_in_found = false;
/* create our private serial structure */
priv = kzalloc(sizeof(*priv), GFP_KERNEL);
if (priv == NULL) {
dev_err(&serial->dev->dev, "%s - Out of memory\n", __func__);
return -ENOMEM;
}
spin_lock_init(&priv->lock);
priv->serial = serial;
priv->port = serial->port[0];
priv->udev = serial->dev;
priv->outstanding_urbs = 0; /* Init the outstanding urbs */
/* find our bulk endpoint */
intf = serial->interface->altsetting;
for (i = 0; i < intf->desc.bNumEndpoints; ++i) {
struct usb_endpoint_descriptor *endpoint;
endpoint = &intf->endpoint[i].desc;
if (!usb_endpoint_is_bulk_in(endpoint))
continue;
priv->bulk_read_urb = usb_alloc_urb(0, GFP_KERNEL);
if (!priv->bulk_read_urb) {
dev_err(&priv->udev->dev, "out of memory\n");
goto error;
}
priv->buffer_size = le16_to_cpu(endpoint->wMaxPacketSize) * 2;
priv->bulk_in_buffer = kmalloc(priv->buffer_size, GFP_KERNEL);
if (!priv->bulk_in_buffer) {
dev_err(&priv->udev->dev, "out of memory\n");
goto error;
}
priv->bulk_address = endpoint->bEndpointAddress;
bulk_in_found = true;
break;
}
if (!bulk_in_found) {
dev_err(&priv->udev->dev,
"Error - the proper endpoints were not found!\n");
goto error;
}
usb_set_serial_data(serial, priv);
return 0;
error:
usb_free_urb(priv->bulk_read_urb);
kfree(priv->bulk_in_buffer);
kfree(priv);
return retval;
}
static void opticon_disconnect(struct usb_serial *serial)
{
struct opticon_private *priv = usb_get_serial_data(serial);
dbg("%s", __func__);
usb_kill_urb(priv->bulk_read_urb);
usb_free_urb(priv->bulk_read_urb);
}
static void opticon_release(struct usb_serial *serial)
{
struct opticon_private *priv = usb_get_serial_data(serial);
dbg("%s", __func__);
kfree(priv->bulk_in_buffer);
kfree(priv);
}
static int opticon_suspend(struct usb_interface *intf, pm_message_t message)
{
struct usb_serial *serial = usb_get_intfdata(intf);
struct opticon_private *priv = usb_get_serial_data(serial);
usb_kill_urb(priv->bulk_read_urb);
return 0;
}
static int opticon_resume(struct usb_interface *intf)
{
struct usb_serial *serial = usb_get_intfdata(intf);
struct opticon_private *priv = usb_get_serial_data(serial);
struct usb_serial_port *port = serial->port[0];
int result;
mutex_lock(&port->port.mutex);
/* This is protected by the port mutex against close/open */
if (test_bit(ASYNCB_INITIALIZED, &port->port.flags))
result = usb_submit_urb(priv->bulk_read_urb, GFP_NOIO);
else
result = 0;
mutex_unlock(&port->port.mutex);
return result;
}
static struct usb_driver opticon_driver = {
.name = "opticon",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.suspend = opticon_suspend,
.resume = opticon_resume,
.id_table = id_table,
.no_dynamic_id = 1,
};
static struct usb_serial_driver opticon_device = {
.driver = {
.owner = THIS_MODULE,
.name = "opticon",
},
.id_table = id_table,
.usb_driver = &opticon_driver,
.num_ports = 1,
.attach = opticon_startup,
.open = opticon_open,
.close = opticon_close,
.write = opticon_write,
.write_room = opticon_write_room,
.disconnect = opticon_disconnect,
.release = opticon_release,
.throttle = opticon_throttle,
.unthrottle = opticon_unthrottle,
.ioctl = opticon_ioctl,
.tiocmget = opticon_tiocmget,
.tiocmset = opticon_tiocmset,
};
static int __init opticon_init(void)
{
int retval;
retval = usb_serial_register(&opticon_device);
if (retval)
return retval;
retval = usb_register(&opticon_driver);
if (retval)
usb_serial_deregister(&opticon_device);
return retval;
}
static void __exit opticon_exit(void)
{
usb_deregister(&opticon_driver);
usb_serial_deregister(&opticon_device);
}
module_init(opticon_init);
module_exit(opticon_exit);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");