usbserial.c

linux-2.4.29操作系统的源码

	/* pass on to the driver specific version of this function */
	if (serial->type->unthrottle)
		serial->type->unthrottle(port);

exit:
	up (&port->sem);
}

static int serial_ioctl (struct tty_struct *tty, struct file * file, unsigned int cmd, unsigned long arg)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;
	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
	int retval = -ENODEV;

	if (!serial)
		return -ENODEV;

	down (&port->sem);

	dbg("%s - port %d, cmd 0x%.4x", __FUNCTION__, port->number, cmd);

	if (!port->open_count) {
		dbg ("%s - port not open", __FUNCTION__);
		goto exit;
	}

	/* pass on to the driver specific version of this function if it is available */
	if (serial->type->ioctl)
		retval = serial->type->ioctl(port, file, cmd, arg);
	else
		retval = -ENOIOCTLCMD;

exit:
	up (&port->sem);
	return retval;
}

static void serial_set_termios (struct tty_struct *tty, struct termios * old)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;
	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);

	if (!serial)
		return;

	down (&port->sem);

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (!port->open_count) {
		dbg("%s - port not open", __FUNCTION__);
		goto exit;
	}

	/* pass on to the driver specific version of this function if it is available */
	if (serial->type->set_termios)
		serial->type->set_termios(port, old);

exit:
	up (&port->sem);
}

static void serial_break (struct tty_struct *tty, int break_state)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;
	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);

	if (!serial)
		return;

	down (&port->sem);

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (!port->open_count) {
		dbg("%s - port not open", __FUNCTION__);
		goto exit;
	}

	/* pass on to the driver specific version of this function if it is available */
	if (serial->type->break_ctl)
		serial->type->break_ctl(port, break_state);

exit:
	up (&port->sem);
}

static void serial_shutdown (struct usb_serial *serial)
{
	dbg ("%s", __FUNCTION__);

	if (serial->type->shutdown)
		serial->type->shutdown(serial);
	else
		generic_shutdown(serial);
}

static int serial_read_proc (char *page, char **start, off_t off, int count, int *eof, void *data)
{
	struct usb_serial *serial;
	int length = 0;
	int i;
	off_t begin = 0;
	char tmp[40];

	dbg("%s", __FUNCTION__);
	length += sprintf (page, "usbserinfo:1.0 driver:%s\n", DRIVER_VERSION);
	for (i = 0; i < SERIAL_TTY_MINORS && length < PAGE_SIZE; ++i) {
		serial = get_serial_by_minor(i);
		if (serial == NULL)
			continue;

		length += sprintf (page+length, "%d:", i);
		if (serial->type->owner)
			length += sprintf (page+length, " module:%s", serial->type->owner->name);
		length += sprintf (page+length, " name:\"%s\"", serial->type->name);
		length += sprintf (page+length, " vendor:%04x product:%04x", serial->vendor, serial->product);
		length += sprintf (page+length, " num_ports:%d", serial->num_ports);
		length += sprintf (page+length, " port:%d", i - serial->minor + 1);

		usb_make_path(serial->dev, tmp, sizeof(tmp));
		length += sprintf (page+length, " path:%s", tmp);
			
		length += sprintf (page+length, "\n");
		if ((length + begin) > (off + count))
			goto done;
		if ((length + begin) < off) {
			begin += length;
			length = 0;
		}
	}
	*eof = 1;
done:
	if (off >= (length + begin))
		return 0;
	*start = page + (off-begin);
	return ((count < begin+length-off) ? count : begin+length-off);
}

/*****************************************************************************
 * generic devices specific driver functions
 *****************************************************************************/
static int generic_open (struct usb_serial_port *port, struct file *filp)
{
	struct usb_serial *serial = port->serial;
	int result = 0;

	if (port_paranoia_check (port, __FUNCTION__))
		return -ENODEV;

	dbg("%s - port %d", __FUNCTION__, 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 (port->tty)
		port->tty->low_latency = 1;

	/* if we have a bulk interrupt, 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 :
				     generic_read_bulk_callback),
				   port);
		result = usb_submit_urb(port->read_urb);
		if (result)
			err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
	}

	return result;
}

static void generic_cleanup (struct usb_serial_port *port)
{
	struct usb_serial *serial = port->serial;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (serial->dev) {
		/* shutdown any bulk reads that might be going on */
		if (serial->num_bulk_out)
			usb_unlink_urb (port->write_urb);
		if (serial->num_bulk_in)
			usb_unlink_urb (port->read_urb);
	}
}

static void generic_close (struct usb_serial_port *port, struct file * filp)
{
	dbg("%s - port %d", __FUNCTION__, port->number);
	generic_cleanup (port);
}

static int generic_write (struct usb_serial_port *port, int from_user, const unsigned char *buf, int count)
{
	struct usb_serial *serial = port->serial;
	int result;
	unsigned long flags;

	if (count == 0) {
		dbg("%s - write request of 0 bytes", __FUNCTION__);
		return (0);
	}
	if (count < 0) {
		err("%s - port %d: write request of %d bytes", __FUNCTION__,
		    port->number, count);
		return (0);
	}

	/* only do something if we have a bulk out endpoint */
	if (serial->num_bulk_out) {
		if (port->write_busy) {
			/* Happens when two threads run port_helper. Watch. */
			info("%s - already writing", __FUNCTION__);
			return (0);
		}

		count = (count > port->bulk_out_size) ? port->bulk_out_size : count;

		if (from_user) {
			if (copy_from_user(port->write_urb->transfer_buffer, buf, count))
				return -EFAULT;
		} else {
			memcpy (port->write_urb->transfer_buffer, buf, count);
		}
		dbg("%s - port %d [%d]", __FUNCTION__, port->number, count);

		/* 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 :
				     generic_write_bulk_callback), port);

		/* send the data out the bulk port */
		port->write_busy = 1;
		result = usb_submit_urb(port->write_urb);
		if (result) {
			err("%s - port %d: failed submitting write urb (%d)",
			     __FUNCTION__, port->number, result);
			port->write_busy = 0;
			spin_lock_irqsave(&post_lock, flags);
			if (port->write_backlog != 0)
				schedule_task(&post_task);
			spin_unlock_irqrestore(&post_lock, flags);

		} else
			result = count;

		return result;
	}

	/* no bulk out, so return 0 bytes written */
	return (0);
}

static int generic_write_room (struct usb_serial_port *port)
{
	struct usb_serial *serial = port->serial;
	int room = 0;

	if (serial->num_bulk_out) {
		if (!port->write_busy && port->write_backlog == 0)
			room = port->bulk_out_size;
	}

	dbg("%s - port %d, returns %d", __FUNCTION__, port->number, room);
	return (room);
}

static int generic_chars_in_buffer (struct usb_serial_port *port)
{
	struct usb_serial *serial = port->serial;
	int chars = 0;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (serial->num_bulk_out) {
		if (port->write_busy)
			chars += port->write_urb->transfer_buffer_length;
		chars += port->write_backlog;	/* spin_lock... Baah */
	}

	dbg("%s - returns %d", __FUNCTION__, chars);
	return (chars);
}

static void generic_read_bulk_callback (struct urb *urb)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
	struct tty_struct *tty;
	unsigned char *data = urb->transfer_buffer;
	int i;
	int result;

	dbg("%s - port %d", __FUNCTION__, port->number);

	if (!serial) {
		dbg("%s - bad serial pointer, exiting", __FUNCTION__);
		return;
	}

	if (urb->status) {
		dbg("%s - nonzero read bulk status received: %d", __FUNCTION__, urb->status);
		return;
	}

	usb_serial_debug_data (__FILE__, __FUNCTION__, urb->actual_length, data);

	tty = port->tty;
	if (tty && urb->actual_length) {
		for (i = 0; i < urb->actual_length ; ++i) {
			/* if we insert more than TTY_FLIPBUF_SIZE characters, we drop them. */
			if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
				tty_flip_buffer_push(tty);
			}
			/* this doesn't actually push the data through unless tty->low_latency is set */
			tty_insert_flip_char(tty, data[i], 0);
		}
	  	tty_flip_buffer_push(tty);
	}

	/* Continue trying to always read  */
	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 : 
			     generic_read_bulk_callback), port);
	result = usb_submit_urb(port->read_urb);
	if (result)
		err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
}

static void generic_write_bulk_callback (struct urb *urb)
{
	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);

	dbg("%s - port %d", __FUNCTION__, port->number);

	port->write_busy = 0;
	wmb();

	if (!serial) {
		err("%s - null serial pointer, exiting", __FUNCTION__);
		return;
	}

	if (urb->status) {
		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
	}

	queue_task(&port->tqueue, &tq_immediate);
	mark_bh(IMMEDIATE_BH);

	return;
}

static void generic_shutdown (struct usb_serial *serial)
{
	int i;

	dbg("%s", __FUNCTION__);

	/* stop reads and writes on all ports */
	for (i=0; i < serial->num_ports; ++i) {
		generic_cleanup (&serial->port[i]);
	}
}

static void port_softint(void *private)
{
	struct usb_serial_port *port = (struct usb_serial_port *)private;
	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
	struct tty_struct *tty;
	unsigned long flags;
	struct tty_ldisc *ld;

	dbg("%s - port %d", __FUNCTION__, port->number);
	
	if (!serial)
		return;

	spin_lock_irqsave(&post_lock, flags);
	if (port->write_backlog != 0)
		schedule_task(&post_task);
	spin_unlock_irqrestore(&post_lock, flags);

	tty = port->tty;
	if (!tty)
		return;

	if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP))) {
		ld = tty_ldisc_ref(tty);
		if(ld) {
			if(ld->write_wakeup) {
				ld->write_wakeup(tty);
				dbg("%s - write wakeup call.", __FUNCTION__);
			}
			tty_ldisc_deref(ld);
		}
	}

	wake_up_interruptible(&tty->write_wait);
}


static void * usb_serial_probe(struct usb_device *dev, unsigned int ifnum,
			       const struct usb_device_id *id)
{
	struct usb_serial *serial = NULL;
	struct usb_serial_port *port;
	struct usb_interface *interface;
	struct usb_interface_descriptor *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
	struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
	struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
	struct usb_serial_device_type *type = NULL;
	struct list_head *tmp;
	int found;
	int minor;
	int buffer_size;
	int i;
	int num_interrupt_in = 0;
	int num_bulk_in = 0;
	int num_bulk_out = 0;
	int num_ports;
	int max_endpoints;
	const struct usb_device_id *id_pattern = NULL;
	unsigned long flags;

	/* loop through our list of known serial converters, and see if this
	   device matches. */
	found = 0;
	interface = &dev->actconfig->interface[ifnum];
	list_for_each (tmp, &usb_serial_driver_list) {
		type = list_entry(tmp, struct usb_serial_device_type, driver_list);
		id_pattern = usb_match_id(dev, interface, type->id_table);
		if (id_pattern != NULL) {
			dbg("descriptor matches");
			found = 1;
			break;
		}
	}
	if (!found) {
		/* no match */
		dbg("none matched");
		return(NULL);
	}
	
	/* descriptor matches, let's find the endpoints needed */
	/* check out the endpoints */
	iface_desc = &interface->altsetting[0];
	for (i = 0; i < iface_desc->bNumEndpoints; ++i) {
		endpoint = &iface_desc->endpoint[i];
		
		if ((endpoint->bEndpointAddress & 0x80) &&