pl2303.c

linux-2.4.29操作系统的源码

	port->read_urb->dev = serial->dev;
	result = usb_submit_urb (port->read_urb);
	if (result) {
		err("%s - failed submitting read urb, error %d", __FUNCTION__, result);
		pl2303_close (port, NULL);
		return -EPROTO;
	}

	dbg("%s - submitting interrupt urb", __FUNCTION__);
	port->interrupt_in_urb->dev = serial->dev;
	result = usb_submit_urb (port->interrupt_in_urb);
	if (result) {
		err("%s - failed submitting interrupt urb, error %d", __FUNCTION__, result);
		pl2303_close (port, NULL);
		return -EPROTO;
	}
	return 0;
}


static void pl2303_close (struct usb_serial_port *port, struct file *filp)
{
	struct usb_serial *serial;
	struct pl2303_private *priv;
	unsigned long flags;
	unsigned int c_cflag;
	int result;

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

	if (serial->dev) {
		if (port->tty) {
			c_cflag = port->tty->termios->c_cflag;
			if (c_cflag & HUPCL) {
				/* drop DTR and RTS */
				priv = usb_get_serial_port_data(port);
				spin_lock_irqsave(&priv->lock, flags);
				priv->line_control = 0;
				spin_unlock_irqrestore (&priv->lock, flags);
				set_control_lines (port->serial->dev, 0);
			}
		}

		/* shutdown our urbs */
		dbg("%s - shutting down urbs", __FUNCTION__);
		result = usb_unlink_urb (port->write_urb);
		if (result)
			dbg("%s - usb_unlink_urb (write_urb)"
			    " failed with reason: %d", __FUNCTION__,
			     result);

		result = usb_unlink_urb (port->read_urb);
		if (result)
			dbg("%s - usb_unlink_urb (read_urb) "
			    "failed with reason: %d", __FUNCTION__,
			     result);

		result = usb_unlink_urb (port->interrupt_in_urb);
		if (result)
			dbg("%s - usb_unlink_urb (interrupt_in_urb)"
			    " failed with reason: %d", __FUNCTION__,
			     result);
	}
}

static int set_modem_info (struct usb_serial_port *port, unsigned int cmd, unsigned int *value)
{
	struct pl2303_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	unsigned int arg;
	u8 control;

	if (copy_from_user(&arg, value, sizeof(int)))
		return -EFAULT;

	spin_lock_irqsave (&priv->lock, flags);
	switch (cmd) {
		case TIOCMBIS:
			if (arg & TIOCM_RTS)
				priv->line_control |= CONTROL_RTS;
			if (arg & TIOCM_DTR)
				priv->line_control |= CONTROL_DTR;
			break;

		case TIOCMBIC:
			if (arg & TIOCM_RTS)
				priv->line_control &= ~CONTROL_RTS;
			if (arg & TIOCM_DTR)
				priv->line_control &= ~CONTROL_DTR;
			break;

		case TIOCMSET:
			/* turn off RTS and DTR and then only turn
			   on what was asked to */
			priv->line_control &= ~(CONTROL_RTS | CONTROL_DTR);
			priv->line_control |= ((arg & TIOCM_RTS) ? CONTROL_RTS : 0);
			priv->line_control |= ((arg & TIOCM_DTR) ? CONTROL_DTR : 0);
			break;
	}
	control = priv->line_control;
	spin_unlock_irqrestore (&priv->lock, flags);

	return set_control_lines (port->serial->dev, control);
}

static int get_modem_info (struct usb_serial_port *port, unsigned int *value)
{
	struct pl2303_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	unsigned int mcr;
	unsigned int status;
	unsigned int result;

	spin_lock_irqsave (&priv->lock, flags);
	mcr = priv->line_control;
	status = priv->line_status;
	spin_unlock_irqrestore (&priv->lock, flags);

	result = ((mcr & CONTROL_DTR)		? TIOCM_DTR : 0)
		  | ((mcr & CONTROL_RTS)	? TIOCM_RTS : 0)
		  | ((status & UART_CTS)	? TIOCM_CTS : 0)
		  | ((status & UART_DSR)	? TIOCM_DSR : 0)
		  | ((status & UART_RING)	? TIOCM_RI  : 0)
		  | ((status & UART_DCD)	? TIOCM_CD  : 0);

	dbg("%s - result = %x", __FUNCTION__, result);

	if (copy_to_user(value, &result, sizeof(int)))
		return -EFAULT;
	return 0;
}

static int wait_modem_info(struct usb_serial_port *port, unsigned int arg)
{
	struct pl2303_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	unsigned int prevstatus;
	unsigned int status;
	unsigned int changed;

	spin_lock_irqsave (&priv->lock, flags);
	prevstatus = priv->line_status;
	spin_unlock_irqrestore (&priv->lock, flags);

	while (1) {
		interruptible_sleep_on(&priv->delta_msr_wait);
		/* see if a signal did it */
		if (signal_pending(current))
			return -ERESTARTSYS;
		
		spin_lock_irqsave (&priv->lock, flags);
		status = priv->line_status;
		spin_unlock_irqrestore (&priv->lock, flags);
		
		changed=prevstatus^status;
		
		if (((arg & TIOCM_RNG) && (changed & UART_RING)) ||
		    ((arg & TIOCM_DSR) && (changed & UART_DSR)) ||
		    ((arg & TIOCM_CD)  && (changed & UART_DCD)) ||
		    ((arg & TIOCM_CTS) && (changed & UART_CTS)) ) {
			return 0;
		}
		prevstatus = status;
	}
	/* NOTREACHED */
	return 0;
}

static int pl2303_ioctl (struct usb_serial_port *port, struct file *file, unsigned int cmd, unsigned long arg)
{
	dbg("%s (%d) cmd = 0x%04x", __FUNCTION__, port->number, cmd);

	switch (cmd) {
		
		case TIOCMGET:
			dbg("%s (%d) TIOCMGET", __FUNCTION__, port->number);
			return get_modem_info (port, (unsigned int *)arg);

		case TIOCMBIS:
		case TIOCMBIC:
		case TIOCMSET:
			dbg("%s (%d) TIOCMSET/TIOCMBIC/TIOCMSET", __FUNCTION__,  port->number);
			return set_modem_info(port, cmd, (unsigned int *) arg);

		case TIOCMIWAIT:
			dbg("%s (%d) TIOCMIWAIT", __FUNCTION__,  port->number);
			return wait_modem_info(port, arg);
		
		default:
			dbg("%s not supported = 0x%04x", __FUNCTION__, cmd);
			break;
	}

	return -ENOIOCTLCMD;
}

static void pl2303_break_ctl (struct usb_serial_port *port, int break_state)
{
	struct usb_serial *serial = port->serial;
	u16 state;
	int result;

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

	if (break_state == 0)
		state = BREAK_OFF;
	else
		state = BREAK_ON;
	dbg("%s - turning break %s", __FUNCTION__, state==BREAK_OFF ? "off" : "on");

	result = usb_control_msg (serial->dev, usb_sndctrlpipe (serial->dev, 0),
				  BREAK_REQUEST, BREAK_REQUEST_TYPE, state, 
				  0, NULL, 0, 100);
	if (result)
		dbg("%s - error sending break = %d", __FUNCTION__, result);
}


static void pl2303_shutdown (struct usb_serial *serial)
{
	int i;

	dbg("%s", __FUNCTION__);

	for (i = 0; i < serial->num_ports; ++i) {
		kfree (usb_get_serial_port_data(&serial->port[i]));
		usb_set_serial_port_data(&serial->port[i], NULL);
	}		
}


static void pl2303_read_int_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 pl2303_private *priv = usb_get_serial_port_data(port);
	unsigned char *data = urb->transfer_buffer;
	unsigned long flags;
	u8 uart_state;

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

	/* ints auto restart... */

	switch (urb->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", __FUNCTION__, urb->status);
		return;
	default:
		dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
		return;
	}

	if (!serial) {
		return;
	}

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

	if (urb->actual_length < UART_STATE)
		return;

	/* Save off the uart status for others to look at */
	uart_state = data[UART_STATE];
	spin_lock_irqsave(&priv->lock, flags);
	uart_state |= (priv->line_status & UART_STATE_TRANSIENT_MASK);
	priv->line_status = uart_state;
	spin_unlock_irqrestore(&priv->lock, flags);
	wake_up_interruptible (&priv->delta_msr_wait);

	return;
}


static void pl2303_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 pl2303_private *priv = usb_get_serial_port_data(port);
	struct tty_struct *tty;
	unsigned char *data = urb->transfer_buffer;
	unsigned long flags;
	int i;
	int result;
	u8 status;
	char tty_flag;

	if (port_paranoia_check (port, __FUNCTION__))
		return;

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

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

	if (urb->status) {
		dbg("%s - urb->status = %d", __FUNCTION__, urb->status);
		if (!port->open_count) {
			dbg("%s - port is closed, exiting.", __FUNCTION__);
			return;
		}
		if (urb->status == -EPROTO) {
			/* PL2303 mysteriously fails with -EPROTO reschedule the read */
			dbg("%s - caught -EPROTO, resubmitting the urb", __FUNCTION__);
			urb->status = 0;
			urb->dev = serial->dev;
			result = usb_submit_urb(urb);
			if (result)
				err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
			return;
		}
		dbg("%s - unable to handle the error, exiting.", __FUNCTION__);
		return;
	}

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

	/* get tty_flag from status */
	tty_flag = TTY_NORMAL;

	spin_lock_irqsave(&priv->lock, flags);
	status = priv->line_status;
	priv->line_status &= ~UART_STATE_TRANSIENT_MASK;
	spin_unlock_irqrestore(&priv->lock, flags);
	wake_up_interruptible (&priv->delta_msr_wait); //AF from 2.6

	/* break takes precedence over parity, */
	/* which takes precedence over framing errors */
	if (status & UART_BREAK_ERROR )
		tty_flag = TTY_BREAK;
	else if (status & UART_PARITY_ERROR)
		tty_flag = TTY_PARITY;
	else if (status & UART_FRAME_ERROR)
		tty_flag = TTY_FRAME;
	dbg("%s - tty_flag = %d", __FUNCTION__, tty_flag);

	tty = port->tty;
	if (tty && urb->actual_length) {
		/* overrun is special, not associated with a char */
		if (status & UART_OVERRUN_ERROR)
			tty_insert_flip_char(tty, 0, TTY_OVERRUN);

		for (i = 0; i < urb->actual_length; ++i) {
			if (tty->flip.count >= TTY_FLIPBUF_SIZE) {
				tty_flip_buffer_push(tty);
			}
			tty_insert_flip_char (tty, data[i], tty_flag);
		}
		tty_flip_buffer_push (tty);
	}

	/* Schedule the next read _if_ we are still open */
	if (port->open_count) {
		urb->dev = serial->dev;
		result = usb_submit_urb(urb);
		if (result)
			err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);
	}

	return;
}



static void pl2303_write_bulk_callback (struct urb *urb)
{
	struct usb_serial_port *port = (struct usb_serial_port *) urb->context;
	int result;

	if (port_paranoia_check (port, __FUNCTION__))
		return;
	
	dbg("%s - port %d", __FUNCTION__, port->number);
	
	if (urb->status) {
		/* error in the urb, so we have to resubmit it */
		if (serial_paranoia_check (port->serial, __FUNCTION__)) {
			return;
		}
		dbg("%s - Overflow in write", __FUNCTION__);
		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__, urb->status);
		port->write_urb->transfer_buffer_length = 1;
		port->write_urb->dev = port->serial->dev;
		result = usb_submit_urb (port->write_urb);
		if (result)
			err("%s - failed resubmitting write urb, error %d", __FUNCTION__, result);

		return;
	}

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

	return;
}


static int __init pl2303_init (void)
{
	int retval;
	retval = usb_serial_register(&pl2303_device);
	if (retval)
		goto failed_usb_serial_register;
	info(DRIVER_DESC " " DRIVER_VERSION);
	return 0;
failed_usb_serial_register:
	return retval;
}


static void __exit pl2303_exit (void)
{
	usb_serial_deregister (&pl2303_device);
}


module_init(pl2303_init);
module_exit(pl2303_exit);

MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

MODULE_PARM(debug, "i");
MODULE_PARM_DESC(debug, "Debug enabled or not");