usb-serial.c

h内核

{
	struct usb_serial *serial;
	struct usb_serial_port *port;
	unsigned int portNumber;
	int retval;
	
	dbg("%s", __FUNCTION__);

	/* get the serial object associated with this tty pointer */
	serial = usb_serial_get_by_index(tty->index);
	if (!serial) {
		tty->driver_data = NULL;
		return -ENODEV;
	}

	portNumber = tty->index - serial->minor;
	port = serial->port[portNumber];
	 
	++port->open_count;

	if (port->open_count == 1) {

		/* set up our port structure making the tty driver
		 * remember our port object, and us it */
		tty->driver_data = port;
		port->tty = tty;

		/* lock this module before we call it
		 * this may fail, which means we must bail out,
		 * safe because we are called with BKL held */
		if (!try_module_get(serial->type->owner)) {
			retval = -ENODEV;
			goto bailout_kref_put;
		}

		/* only call the device specific open if this 
		 * is the first time the port is opened */
		retval = serial->type->open(port, filp);
		if (retval)
			goto bailout_module_put;
	}

	return 0;

bailout_module_put:
	module_put(serial->type->owner);
bailout_kref_put:
	kref_put(&serial->kref, destroy_serial);
	port->open_count = 0;
	return retval;
}

static void serial_close(struct tty_struct *tty, struct file * filp)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;

	if (!port)
		return;

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

	if (port->open_count == 0)
		return;

	--port->open_count;
	if (port->open_count == 0) {
		/* only call the device specific close if this 
		 * port is being closed by the last owner */
		port->serial->type->close(port, filp);

		if (port->tty) {
			if (port->tty->driver_data)
				port->tty->driver_data = NULL;
			port->tty = NULL;
		}

		module_put(port->serial->type->owner);
	}

	kref_put(&port->serial->kref, destroy_serial);
}

static int serial_write (struct tty_struct * tty, const unsigned char *buf, int count)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;
	int retval = -EINVAL;

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

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

	/* pass on to the driver specific version of this function */
	retval = port->serial->type->write(port, buf, count);

exit:
	return retval;
}

static int serial_write_room (struct tty_struct *tty) 
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;
	int retval = -EINVAL;

	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 */
	retval = port->serial->type->write_room(port);

exit:
	return retval;
}

static int serial_chars_in_buffer (struct tty_struct *tty) 
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;
	int retval = -EINVAL;

	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 */
	retval = port->serial->type->chars_in_buffer(port);

exit:
	return retval;
}

static void serial_throttle (struct tty_struct * tty)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;

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

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

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

static void serial_unthrottle (struct tty_struct * tty)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;

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

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

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

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;
	int retval = -ENODEV;

	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 (port->serial->type->ioctl)
		retval = port->serial->type->ioctl(port, file, cmd, arg);
	else
		retval = -ENOIOCTLCMD;

exit:
	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;

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

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

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

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

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

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

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

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 = usb_serial_get_by_index(i);
		if (serial == NULL)
			continue;

		length += sprintf (page+length, "%d:", i);
		if (serial->type->owner)
			length += sprintf (page+length, " module:%s", module_name(serial->type->owner));
		length += sprintf (page+length, " name:\"%s\"", serial->type->name);
		length += sprintf (page+length, " vendor:%04x product:%04x", 
				   le16_to_cpu(serial->dev->descriptor.idVendor), 
				   le16_to_cpu(serial->dev->descriptor.idProduct));
		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;
		}
		kref_put(&serial->kref, destroy_serial);
	}
	*eof = 1;
done:
	if (off >= (length + begin))
		return 0;
	*start = page + (off-begin);
	return ((count < begin+length-off) ? count : begin+length-off);
}

static int serial_tiocmget (struct tty_struct *tty, struct file *file)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;

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

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

	if (port->serial->type->tiocmget)
		return port->serial->type->tiocmget(port, file);

exit:
	return -EINVAL;
}

static int serial_tiocmset (struct tty_struct *tty, struct file *file,
			    unsigned int set, unsigned int clear)
{
	struct usb_serial_port *port = (struct usb_serial_port *) tty->driver_data;

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

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

	if (port->serial->type->tiocmset)
		return port->serial->type->tiocmset(port, file, set, clear);

exit:
	return -EINVAL;
}

void usb_serial_port_softint(void *private)
{
	struct usb_serial_port *port = (struct usb_serial_port *)private;
	struct tty_struct *tty;

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

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

	tty_wakeup(tty);
}

static void port_release(struct device *dev)
{
	struct usb_serial_port *port = to_usb_serial_port(dev);

	dbg ("%s - %s", __FUNCTION__, dev->bus_id);
	usb_kill_urb(port->read_urb);
	usb_free_urb(port->read_urb);
	usb_kill_urb(port->write_urb);
	usb_free_urb(port->write_urb);
	usb_kill_urb(port->interrupt_in_urb);
	usb_free_urb(port->interrupt_in_urb);
	usb_kill_urb(port->interrupt_out_urb);
	usb_free_urb(port->interrupt_out_urb);
	kfree(port->bulk_in_buffer);
	kfree(port->bulk_out_buffer);
	kfree(port->interrupt_in_buffer);
	kfree(port->interrupt_out_buffer);
	kfree(port);
}

static struct usb_serial * create_serial (struct usb_device *dev, 
					  struct usb_interface *interface,
					  struct usb_serial_device_type *type)
{
	struct usb_serial *serial;

	serial = kmalloc (sizeof (*serial), GFP_KERNEL);
	if (!serial) {
		dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
		return NULL;
	}
	memset (serial, 0, sizeof(*serial));
	serial->dev = usb_get_dev(dev);
	serial->type = type;
	serial->interface = interface;
	kref_init(&serial->kref);

	return serial;
}

static struct usb_serial_device_type *search_serial_device(struct usb_interface *iface)
{
	struct list_head *p;
	const struct usb_device_id *id;
	struct usb_serial_device_type *t;

	/* List trough know devices and see if the usb id matches */
	list_for_each(p, &usb_serial_driver_list) {
		t = list_entry(p, struct usb_serial_device_type, driver_list);
		id = usb_match_id(iface, t->id_table);
		if (id != NULL) {
			dbg("descriptor matches");
			return t;
		}
	}

	return NULL;
}

int usb_serial_probe(struct usb_interface *interface,
			       const struct usb_device_id *id)
{
	struct usb_device *dev = interface_to_usbdev (interface);
	struct usb_serial *serial = NULL;
	struct usb_serial_port *port;
	struct usb_host_interface *iface_desc;
	struct usb_endpoint_descriptor *endpoint;
	struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
	struct usb_endpoint_descriptor *interrupt_out_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;
	int retval;
	int minor;
	int buffer_size;
	int i;
	int num_interrupt_in = 0;
	int num_interrupt_out = 0;
	int num_bulk_in = 0;
	int num_bulk_out = 0;
	int num_ports = 0;
	int max_endpoints;

	type = search_serial_device(interface);
	if (!type) {
		dbg("none matched");
		return -ENODEV;
	}

	serial = create_serial (dev, interface, type);
	if (!serial) {
		dev_err(&interface->dev, "%s - out of memory\n", __FUNCTION__);
		return -ENOMEM;
	}

	/* if this device type has a probe function, call it */
	if (type->probe) {
		const struct usb_device_id *id;

		if (!try_module_get(type->owner)) {
			dev_err(&interface->dev, "module get failed, exiting\n");
			kfree (serial);
			return -EIO;
		}

		id = usb_match_id(interface, type->id_table);
		retval = type->probe(serial, id);
		module_put(type->owner);

		if (retval) {
			dbg ("sub driver rejected device");
			kfree (serial);
			return retval;
		}
	}

	/* descriptor matches, let's find the endpoints needed */
	/* check out the endpoints */
	iface_desc = interface->cur_altsetting;
	for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
		endpoint = &iface_desc->endpoint[i].desc;
		
		if ((endpoint->bEndpointAddress & 0x80) &&
		    ((endpoint->bmAttributes & 3) == 0x02)) {
			/* we found a bulk in endpoint */
			dbg("found bulk in on endpoint %d", i);
			bulk_in_endpoint[num_bulk_in] = endpoint;
			++num_bulk_in;
		}

		if (((endpoint->bEndpointAddress & 0x80) == 0x00) &&
		    ((endpoint->bmAttributes & 3) == 0x02)) {
			/* we found a bulk out endpoint */
			dbg("found bulk out on endpoint %d", i);
			bulk_out_endpoint[num_bulk_out] = endpoint;
			++num_bulk_out;
		}
		
		if ((endpoint->bEndpointAddress & 0x80) &&
		    ((endpoint->bmAttributes & 3) == 0x03)) {
			/* we found a interrupt in endpoint */
			dbg("found interrupt in on endpoint %d", i);
			interrupt_in_endpoint[num_interrupt_in] = endpoint;
			++num_interrupt_in;
		}

		if (((endpoint->bEndpointAddress & 0x80) == 0x00) &&
		    ((endpoint->bmAttributes & 3) == 0x03)) {
			/* we found an interrupt out endpoint */
			dbg("found interrupt out on endpoint %d", i);
			interrupt_out_endpoint[num_interrupt_out] = endpoint;
			++num_interrupt_out;
		}
	}