ftdi_sio.c

linux-2.6.15.6

	if (baud == 38400 &&
	    ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) &&
	     (priv->custom_divisor)) {
		baud = priv->baud_base / priv->custom_divisor;
		dbg("%s - custom divisor %d sets baud rate to %d", __FUNCTION__, priv->custom_divisor, baud);
	}

	/* 3. Convert baudrate to device-specific divisor */

	if (!baud) baud = 9600;	
	switch(priv->chip_type) {
	case SIO: /* SIO chip */
		switch(baud) {
		case 300: div_value = ftdi_sio_b300; break;
		case 600: div_value = ftdi_sio_b600; break;
		case 1200: div_value = ftdi_sio_b1200; break;
		case 2400: div_value = ftdi_sio_b2400; break;
		case 4800: div_value = ftdi_sio_b4800; break;
		case 9600: div_value = ftdi_sio_b9600; break;
		case 19200: div_value = ftdi_sio_b19200; break;
		case 38400: div_value = ftdi_sio_b38400; break;
		case 57600: div_value = ftdi_sio_b57600;  break;
		case 115200: div_value = ftdi_sio_b115200; break;
		} /* baud */
		if (div_value == 0) {
  			dbg("%s - Baudrate (%d) requested is not supported", __FUNCTION__,  baud);
			div_value = ftdi_sio_b9600;
			div_okay = 0;
		}
		break;
	case FT8U232AM: /* 8U232AM chip */
		if (baud <= 3000000) {
			div_value = ftdi_232am_baud_to_divisor(baud);
		} else {
	                dbg("%s - Baud rate too high!", __FUNCTION__);
			div_value = ftdi_232am_baud_to_divisor(9600);
			div_okay = 0;
		}
		break;
	case FT232BM: /* FT232BM chip */
	case FT2232C: /* FT2232C chip */
		if (baud <= 3000000) {
			div_value = ftdi_232bm_baud_to_divisor(baud);
		} else {
	                dbg("%s - Baud rate too high!", __FUNCTION__);
			div_value = ftdi_232bm_baud_to_divisor(9600);
			div_okay = 0;
		}
		break;
	} /* priv->chip_type */

	if (div_okay) {
		dbg("%s - Baud rate set to %d (divisor 0x%lX) on chip %s",
			__FUNCTION__, baud, (unsigned long)div_value,
			ftdi_chip_name[priv->chip_type]);
	}

	return(div_value);
}


static int get_serial_info(struct usb_serial_port * port, struct serial_struct __user * retinfo)
{
	struct ftdi_private *priv = usb_get_serial_port_data(port);
	struct serial_struct tmp;

	if (!retinfo)
		return -EFAULT;
	memset(&tmp, 0, sizeof(tmp));
	tmp.flags = priv->flags;
	tmp.baud_base = priv->baud_base;
	tmp.custom_divisor = priv->custom_divisor;
	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
		return -EFAULT;
	return 0;
} /* get_serial_info */


static int set_serial_info(struct usb_serial_port * port, struct serial_struct __user * newinfo)
{ /* set_serial_info */
	struct ftdi_private *priv = usb_get_serial_port_data(port);
	struct serial_struct new_serial;
	struct ftdi_private old_priv;

	if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
		return -EFAULT;
	old_priv = * priv;

	/* Do error checking and permission checking */

	if (!capable(CAP_SYS_ADMIN)) {
		if (((new_serial.flags & ~ASYNC_USR_MASK) !=
		     (priv->flags & ~ASYNC_USR_MASK)))
			return -EPERM;
		priv->flags = ((priv->flags & ~ASYNC_USR_MASK) |
			       (new_serial.flags & ASYNC_USR_MASK));
		priv->custom_divisor = new_serial.custom_divisor;
		goto check_and_exit;
	}

	if ((new_serial.baud_base != priv->baud_base) &&
	    (new_serial.baud_base < 9600))
		return -EINVAL;

	/* Make the changes - these are privileged changes! */

	priv->flags = ((priv->flags & ~ASYNC_FLAGS) |
	               (new_serial.flags & ASYNC_FLAGS));	
	priv->custom_divisor = new_serial.custom_divisor;

	port->tty->low_latency = (priv->flags & ASYNC_LOW_LATENCY) ? 1 : 0;

check_and_exit:
	if ((old_priv.flags & ASYNC_SPD_MASK) !=
	     (priv->flags & ASYNC_SPD_MASK)) {
		if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_HI)
			port->tty->alt_speed = 57600;
		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_VHI)
			port->tty->alt_speed = 115200;
		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_SHI)
			port->tty->alt_speed = 230400;
		else if ((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_WARP)
			port->tty->alt_speed = 460800;
		else
			port->tty->alt_speed = 0;
	}
	if (((old_priv.flags & ASYNC_SPD_MASK) !=
	     (priv->flags & ASYNC_SPD_MASK)) ||
	    (((priv->flags & ASYNC_SPD_MASK) == ASYNC_SPD_CUST) &&
	     (old_priv.custom_divisor != priv->custom_divisor))) {
		change_speed(port);
	}
	
	return (0);

} /* set_serial_info */


/* Determine type of FTDI chip based on USB config and descriptor. */
static void ftdi_determine_type(struct usb_serial_port *port)
{
	struct ftdi_private *priv = usb_get_serial_port_data(port);
	struct usb_serial *serial = port->serial;
	struct usb_device *udev = serial->dev;
	unsigned version;
	unsigned interfaces;

	/* Assume it is not the original SIO device for now. */
	priv->baud_base = 48000000 / 2;
	priv->write_offset = 0;

	version = le16_to_cpu(udev->descriptor.bcdDevice);
	interfaces = udev->actconfig->desc.bNumInterfaces;
	dbg("%s: bcdDevice = 0x%x, bNumInterfaces = %u", __FUNCTION__,
			version, interfaces);
	if (interfaces > 1) {
		int inter;

		/* Multiple interfaces.  Assume FT2232C. */
		priv->chip_type = FT2232C;
		/* Determine interface code. */
		inter = serial->interface->altsetting->desc.bInterfaceNumber;
		if (inter == 0) {
			priv->interface = PIT_SIOA;
		} else {
			priv->interface = PIT_SIOB;
		}
		/* BM-type devices have a bug where bcdDevice gets set
		 * to 0x200 when iSerialNumber is 0.  */
		if (version < 0x500) {
			dbg("%s: something fishy - bcdDevice too low for multi-interface device",
					__FUNCTION__);
		}
	} else if (version < 0x200) {
		/* Old device.  Assume its the original SIO. */
		priv->chip_type = SIO;
		priv->baud_base = 12000000 / 16;
		priv->write_offset = 1;
	} else if (version < 0x400) {
		/* Assume its an FT8U232AM (or FT8U245AM) */
		/* (It might be a BM because of the iSerialNumber bug,
		 * but it will still work as an AM device.) */
		priv->chip_type = FT8U232AM;
	} else {
		/* Assume its an FT232BM (or FT245BM) */
		priv->chip_type = FT232BM;
	}
	info("Detected %s", ftdi_chip_name[priv->chip_type]);
}


/*
 * ***************************************************************************
 * Sysfs Attribute
 * ***************************************************************************
 */

static ssize_t show_latency_timer(struct device *dev, struct device_attribute *attr, char *buf)
{
	struct usb_serial_port *port = to_usb_serial_port(dev);
	struct ftdi_private *priv = usb_get_serial_port_data(port);
	struct usb_device *udev;
	unsigned short latency = 0;
	int rv = 0;
	
	udev = to_usb_device(dev);
	
	dbg("%s",__FUNCTION__);
	
	rv = usb_control_msg(udev,
			     usb_rcvctrlpipe(udev, 0),
			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST,
			     FTDI_SIO_GET_LATENCY_TIMER_REQUEST_TYPE,
			     0, priv->interface, 
			     (char*) &latency, 1, WDR_TIMEOUT);
	
	if (rv < 0) {
		dev_err(dev, "Unable to read latency timer: %i", rv);
		return -EIO;
	}
	return sprintf(buf, "%i\n", latency);
}

/* Write a new value of the latency timer, in units of milliseconds. */
static ssize_t store_latency_timer(struct device *dev, struct device_attribute *attr, const char *valbuf,
				   size_t count)
{
	struct usb_serial_port *port = to_usb_serial_port(dev);
	struct ftdi_private *priv = usb_get_serial_port_data(port);
	struct usb_device *udev;
	char buf[1];
	int v = simple_strtoul(valbuf, NULL, 10);
	int rv = 0;
	
	udev = to_usb_device(dev);
	
	dbg("%s: setting latency timer = %i", __FUNCTION__, v);
	
	rv = usb_control_msg(udev,
			     usb_sndctrlpipe(udev, 0),
			     FTDI_SIO_SET_LATENCY_TIMER_REQUEST,
			     FTDI_SIO_SET_LATENCY_TIMER_REQUEST_TYPE,
			     v, priv->interface, 
			     buf, 0, WDR_TIMEOUT);
	
	if (rv < 0) {
		dev_err(dev, "Unable to write latency timer: %i", rv);
		return -EIO;
	}
	
	return count;
}

/* Write an event character directly to the FTDI register.  The ASCII
   value is in the low 8 bits, with the enable bit in the 9th bit. */
static ssize_t store_event_char(struct device *dev, struct device_attribute *attr, const char *valbuf,
				size_t count)
{
	struct usb_serial_port *port = to_usb_serial_port(dev);
	struct ftdi_private *priv = usb_get_serial_port_data(port);
	struct usb_device *udev;
	char buf[1];
	int v = simple_strtoul(valbuf, NULL, 10);
	int rv = 0;
	
	udev = to_usb_device(dev);
	
	dbg("%s: setting event char = %i", __FUNCTION__, v);
	
	rv = usb_control_msg(udev,
			     usb_sndctrlpipe(udev, 0),
			     FTDI_SIO_SET_EVENT_CHAR_REQUEST,
			     FTDI_SIO_SET_EVENT_CHAR_REQUEST_TYPE,
			     v, priv->interface, 
			     buf, 0, WDR_TIMEOUT);
	
	if (rv < 0) {
		dbg("Unable to write event character: %i", rv);
		return -EIO;
	}
	
	return count;
}

static DEVICE_ATTR(latency_timer, S_IWUSR | S_IRUGO, show_latency_timer, store_latency_timer);
static DEVICE_ATTR(event_char, S_IWUSR, NULL, store_event_char);

static void create_sysfs_attrs(struct usb_serial *serial)
{	
	struct ftdi_private *priv;
	struct usb_device *udev;

	dbg("%s",__FUNCTION__);
	
	priv = usb_get_serial_port_data(serial->port[0]);
	udev = serial->dev;
	
	/* XXX I've no idea if the original SIO supports the event_char
	 * sysfs parameter, so I'm playing it safe.  */
	if (priv->chip_type != SIO) {
		dbg("sysfs attributes for %s", ftdi_chip_name[priv->chip_type]);
		device_create_file(&udev->dev, &dev_attr_event_char);
		if (priv->chip_type == FT232BM || priv->chip_type == FT2232C) {
			device_create_file(&udev->dev, &dev_attr_latency_timer);
		}
	}
}

static void remove_sysfs_attrs(struct usb_serial *serial)
{
	struct ftdi_private *priv;
	struct usb_device *udev;

	dbg("%s",__FUNCTION__);	

	priv = usb_get_serial_port_data(serial->port[0]);
	udev = serial->dev;
	
	/* XXX see create_sysfs_attrs */
	if (priv->chip_type != SIO) {
		device_remove_file(&udev->dev, &dev_attr_event_char);
		if (priv->chip_type == FT232BM || priv->chip_type == FT2232C) {
			device_remove_file(&udev->dev, &dev_attr_latency_timer);
		}
	}
	
}

/*
 * ***************************************************************************
 * FTDI driver specific functions
 * ***************************************************************************
 */

/* Probe function to check for special devices */
static int ftdi_sio_probe (struct usb_serial *serial, const struct usb_device_id *id)
{
	usb_set_serial_data(serial, (void *)id->driver_info);

	return (0);
}

/* attach subroutine */
static int ftdi_sio_attach (struct usb_serial *serial)
{
	struct usb_serial_port *port = serial->port[0];
	struct ftdi_private *priv;
	struct ftdi_sio_quirk *quirk;
	
	dbg("%s",__FUNCTION__);

	priv = kmalloc(sizeof(struct ftdi_private), GFP_KERNEL);
	if (!priv){
		err("%s- kmalloc(%Zd) failed.", __FUNCTION__, sizeof(struct ftdi_private));
		return -ENOMEM;
	}
	memset(priv, 0, sizeof(*priv));

	spin_lock_init(&priv->rx_lock);
        init_waitqueue_head(&priv->delta_msr_wait);
	/* This will push the characters through immediately rather
	   than queue a task to deliver them */
	priv->flags = ASYNC_LOW_LATENCY;

	/* Increase the size of read buffers */
	kfree(port->bulk_in_buffer);
	port->bulk_in_buffer = kmalloc (BUFSZ, GFP_KERNEL);
	if (!port->bulk_in_buffer) {
		kfree (priv);
		return -ENOMEM;
	}
	if (port->read_urb) {
		port->read_urb->transfer_buffer = port->bulk_in_buffer;
		port->read_urb->transfer_buffer_length = BUFSZ;
	}

	INIT_WORK(&priv->rx_work, ftdi_process_read, port);

	/* Free port's existing write urb and transfer buffer. */
	if (port->write_urb) {
		usb_free_urb (port->write_urb);
		port->write_urb = NULL;
	}
	kfree(port->bulk_out_buffer);
	port->bulk_out_buffer = NULL;

	usb_set_serial_port_data(serial->port[0], priv);