usbserial.c

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{
	struct usb_serial_port *port = (struct usb_serial_port *)private;
	struct usb_serial *serial = get_usb_serial (port, __FUNCTION__);
	struct tty_struct *tty;

	dbg(__FUNCTION__ " - port %d", port->number);
	
	if (!serial) {
		return;
	}
 	
	tty = port->tty;
	if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup) {
		dbg(__FUNCTION__ " - write wakeup call.");
		(tty->ldisc.write_wakeup)(tty);
	}

	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;
	char interrupt_pipe;
	char bulk_in_pipe;
	char bulk_out_pipe;
	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;

	
	/* 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 */
	interrupt_pipe = bulk_in_pipe = bulk_out_pipe = HAS_NOT;
			
	/* 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) &&
		    ((endpoint->bmAttributes & 3) == 0x02)) {
			/* we found a bulk in endpoint */
			dbg("found bulk in");
			bulk_in_pipe = HAS;
			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");
			bulk_out_pipe = HAS;
			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");
			interrupt_pipe = HAS;
			interrupt_in_endpoint[num_interrupt_in] = endpoint;
			++num_interrupt_in;
		}
	}
	
	/* verify that we found all of the endpoints that we need */
	if (!((interrupt_pipe & type->needs_interrupt_in) &&
	      (bulk_in_pipe & type->needs_bulk_in) &&
	      (bulk_out_pipe & type->needs_bulk_out))) {
		/* nope, they don't match what we expected */
		info("descriptors matched, but endpoints did not");
		return NULL;
	}

	/* found all that we need */
	MOD_INC_USE_COUNT;
	info("%s converter detected", type->name);

#ifdef CONFIG_USB_SERIAL_GENERIC
	if (type == &generic_device) {
		num_ports = num_bulk_out;
		if (num_ports == 0) {
			err("Generic device with no bulk out, not allowed.");
			MOD_DEC_USE_COUNT;
			return NULL;
		}
	} else
#endif
		num_ports = type->num_ports;

	serial = get_free_serial (num_ports, &minor);
	if (serial == NULL) {
		err("No more free serial devices");
		MOD_DEC_USE_COUNT;
		return NULL;
	}
	
	serial->dev = dev;
	serial->type = type;
	serial->interface = interface;
	serial->minor = minor;
	serial->num_ports = num_ports;
	serial->num_bulk_in = num_bulk_in;
	serial->num_bulk_out = num_bulk_out;
	serial->num_interrupt_in = num_interrupt_in;

	/* if this device type has a startup function, call it */
	if (type->startup) {
		if (type->startup (serial)) {
			goto probe_error;
		}
	}

	/* set up the endpoint information */
	for (i = 0; i < num_bulk_in; ++i) {
		endpoint = bulk_in_endpoint[i];
		port = &serial->port[i];
		port->read_urb = usb_alloc_urb (0);
		if (!port->read_urb) {
			err("No free urbs available");
			goto probe_error;
		}
		buffer_size = endpoint->wMaxPacketSize;
		port->bulk_in_endpointAddress = endpoint->bEndpointAddress;
		port->bulk_in_buffer = kmalloc (buffer_size, GFP_KERNEL);
		if (!port->bulk_in_buffer) {
			err("Couldn't allocate bulk_in_buffer");
			goto probe_error;
		}
		FILL_BULK_URB(port->read_urb, dev, 
			      usb_rcvbulkpipe(dev, endpoint->bEndpointAddress),
			      port->bulk_in_buffer, buffer_size, 
			      ((serial->type->read_bulk_callback) ?
			       serial->type->read_bulk_callback :
			       generic_read_bulk_callback), 
			      port);
	}

	for (i = 0; i < num_bulk_out; ++i) {
		endpoint = bulk_out_endpoint[i];
		port = &serial->port[i];
		port->write_urb = usb_alloc_urb(0);
		if (!port->write_urb) {
			err("No free urbs available");
			goto probe_error;
		}
		buffer_size = endpoint->wMaxPacketSize;
		port->bulk_out_size = buffer_size;
		port->bulk_out_endpointAddress = endpoint->bEndpointAddress;
		port->bulk_out_buffer = kmalloc (buffer_size, GFP_KERNEL);
		if (!port->bulk_out_buffer) {
			err("Couldn't allocate bulk_out_buffer");
			goto probe_error;
		}
		FILL_BULK_URB(port->write_urb, dev, 
			      usb_sndbulkpipe(dev, endpoint->bEndpointAddress),
			      port->bulk_out_buffer, buffer_size,
			      ((serial->type->write_bulk_callback) ? 
			       serial->type->write_bulk_callback : 
			       generic_write_bulk_callback), 
			      port);
	}

	for (i = 0; i < num_interrupt_in; ++i) {
		endpoint = interrupt_in_endpoint[i];
		port = &serial->port[i];
		port->interrupt_in_urb = usb_alloc_urb(0);
		if (!port->interrupt_in_urb) {
			err("No free urbs available");
			goto probe_error;
		}
		buffer_size = endpoint->wMaxPacketSize;
		port->interrupt_in_endpointAddress = endpoint->bEndpointAddress;
		port->interrupt_in_buffer = kmalloc (buffer_size, GFP_KERNEL);
		if (!port->interrupt_in_buffer) {
			err("Couldn't allocate interrupt_in_buffer");
			goto probe_error;
		}
		FILL_INT_URB(port->interrupt_in_urb, dev, 
			     usb_rcvintpipe(dev, endpoint->bEndpointAddress),
			     port->interrupt_in_buffer, buffer_size, 
			     serial->type->read_int_callback,
			     port, 
			     endpoint->bInterval);
	}

	/* initialize some parts of the port structures */
	/* we don't use num_ports here cauz some devices have more endpoint pairs than ports */
	max_endpoints = MAX(num_bulk_in, num_bulk_out);
	max_endpoints = MAX(max_endpoints, num_interrupt_in);
	dbg (__FUNCTION__ " - setting up %d port structures for this device", max_endpoints);
	for (i = 0; i < max_endpoints; ++i) {
		port = &serial->port[i];
		port->number = i + serial->minor;
		port->serial = serial;
		port->magic = USB_SERIAL_PORT_MAGIC;
		port->tqueue.routine = port_softint;
		port->tqueue.data = port;
		spin_lock_init (&port->port_lock);
	}
	
	/* initialize the devfs nodes for this device and let the user know what ports we are bound to */
	for (i = 0; i < serial->num_ports; ++i) {
		tty_register_devfs (&serial_tty_driver, 0, serial->port[i].number);
		info("%s converter now attached to ttyUSB%d (or usb/tts/%d for devfs)", 
		     type->name, serial->port[i].number, serial->port[i].number);
	}
	
	return serial; /* success */


probe_error:
	for (i = 0; i < num_bulk_in; ++i) {
		port = &serial->port[i];
		if (port->read_urb)
			usb_free_urb (port->read_urb);
		if (port->bulk_in_buffer)
			kfree (port->bulk_in_buffer);
	}
	for (i = 0; i < num_bulk_out; ++i) {
		port = &serial->port[i];
		if (port->write_urb)
			usb_free_urb (port->write_urb);
		if (port->bulk_out_buffer)
			kfree (port->bulk_out_buffer);
	}
	for (i = 0; i < num_interrupt_in; ++i) {
		port = &serial->port[i];
		if (port->interrupt_in_urb)
			usb_free_urb (port->interrupt_in_urb);
		if (port->interrupt_in_buffer)
			kfree (port->interrupt_in_buffer);
	}
		
	/* return the minor range that this device had */
	return_serial (serial);

	/* free up any memory that we allocated */
	kfree (serial);
	MOD_DEC_USE_COUNT;
	return NULL;
}


static void usb_serial_disconnect(struct usb_device *dev, void *ptr)
{
	struct usb_serial *serial = (struct usb_serial *) ptr;
	struct usb_serial_port *port;
	int i;

	if (serial) {
		/* fail all future close/read/write/ioctl/etc calls */
		for (i = 0; i < serial->num_ports; ++i) {
			if (serial->port[i].tty != NULL)
				serial->port[i].tty->driver_data = NULL;
		}

		if (serial->type->shutdown)
			serial->type->shutdown(serial);

		for (i = 0; i < serial->num_ports; ++i)
			serial->port[i].active = 0;

		for (i = 0; i < serial->num_bulk_in; ++i) {
			port = &serial->port[i];
			if (port->read_urb) {
				usb_unlink_urb (port->read_urb);
				usb_free_urb (port->read_urb);
			}
			if (port->bulk_in_buffer)
				kfree (port->bulk_in_buffer);
		}
		for (i = 0; i < serial->num_bulk_out; ++i) {
			port = &serial->port[i];
			if (port->write_urb) {
				usb_unlink_urb (port->write_urb);
				usb_free_urb (port->write_urb);
			}
			if (port->bulk_out_buffer)
				kfree (port->bulk_out_buffer);
		}
		for (i = 0; i < serial->num_interrupt_in; ++i) {
			port = &serial->port[i];
			if (port->interrupt_in_urb) {
				usb_unlink_urb (port->interrupt_in_urb);
				usb_free_urb (port->interrupt_in_urb);
			}
			if (port->interrupt_in_buffer)
				kfree (port->interrupt_in_buffer);
		}

		for (i = 0; i < serial->num_ports; ++i) {
			tty_unregister_devfs (&serial_tty_driver, serial->port[i].number);
			info("%s converter now disconnected from ttyUSB%d", serial->type->name, serial->port[i].number);
		}

		/* return the minor range that this device had */
		return_serial (serial);

		/* free up any memory that we allocated */
		kfree (serial);

	} else {
		info("device disconnected");
	}
	
	MOD_DEC_USE_COUNT;
}


static struct tty_driver serial_tty_driver = {
	magic:			TTY_DRIVER_MAGIC,
	driver_name:		"usb-serial",
	name:			"usb/tts/%d",
	major:			SERIAL_TTY_MAJOR,
	minor_start:		0,
	num:			SERIAL_TTY_MINORS,
	type:			TTY_DRIVER_TYPE_SERIAL,
	subtype:		SERIAL_TYPE_NORMAL,
	flags:			TTY_DRIVER_REAL_RAW | TTY_DRIVER_NO_DEVFS,
	
	refcount:		&serial_refcount,
	table:			serial_tty,
	termios:		serial_termios,
	termios_locked:		serial_termios_locked,
	
	open:			serial_open,
	close:			serial_close,
	write:			serial_write,
	write_room:		serial_write_room,
	ioctl:			serial_ioctl,
	set_termios:		serial_set_termios,
	throttle:		serial_throttle,
	unthrottle:		serial_unthrottle,
	break_ctl:		serial_break,
	chars_in_buffer:	serial_chars_in_buffer,
};


int usb_serial_init(void)
{
	int i;
	int result;

	/* Initalize our global data */
	for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
		serial_table[i] = NULL;
	}

	/* register the tty driver */
	serial_tty_driver.init_termios          = tty_std_termios;
	serial_tty_driver.init_termios.c_cflag  = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
	if (tty_register_driver (&serial_tty_driver)) {
		err(__FUNCTION__ " - failed to register tty driver");
		return -1;
	}

#ifdef CONFIG_USB_SERIAL_GENERIC
	generic_device_ids[0].idVendor = vendor;
	generic_device_ids[0].idProduct = product;
	/* register our generic driver with ourselves */
	usb_serial_register (&generic_device);
#endif
	
	/* register the USB driver */
	result = usb_register(&usb_serial_driver);
	if (result < 0) {
		tty_unregister_driver(&serial_tty_driver);
		err("usb_register failed for the usb-serial driver. Error number %d", result);
		return -1;
	}
	
	
	return 0;
}


void usb_serial_exit(void)
{

#ifdef CONFIG_USB_SERIAL_GENERIC
	/* remove our generic driver */
	usb_serial_deregister (&generic_device);
#endif
	
	usb_deregister(&usb_serial_driver);
	tty_unregister_driver(&serial_tty_driver);
}


module_init(usb_serial_init);
module_exit(usb_serial_exit);


int usb_serial_register(struct usb_serial_device_type *new_device)
{
	/* Add this device to our list of devices */
	list_add(&new_device->driver_list, &usb_serial_driver_list);

	info ("USB Serial support registered for %s", new_device->name);

	usb_scan_devices();

	return 0;
}


void usb_serial_deregister(struct usb_serial_device_type *device)
{
	struct usb_serial *serial;
	int i;

	info("USB Serial deregistering driver %s", device->name);

	/* clear out the serial_table if the device is attached to a port */
	for(i = 0; i < SERIAL_TTY_MINORS; ++i) {
		serial = serial_table[i];
		if ((serial != NULL) && (serial->type == device)) {
			usb_driver_release_interface (&usb_serial_driver, serial->interface);
			usb_serial_disconnect (NULL, serial);
		}
	}

	list_del(&device->driver_list);
}



/* If the usb-serial core is build into the core, the usb-serial drivers
   need these symbols to load properly as modules. */
EXPORT_SYMBOL(usb_serial_register);
EXPORT_SYMBOL(usb_serial_deregister);
#ifdef USES_EZUSB_FUNCTIONS
	EXPORT_SYMBOL(ezusb_writememory);
	EXPORT_SYMBOL(ezusb_set_reset);
#endif