pl2303.c

底层驱动开发

	
	i = usb_control_msg (serial->dev, usb_rcvctrlpipe (serial->dev, 0),
			     GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
			     0, 0, buf, 7, 100);
	dbg ("0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x", i,
	     buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);


	if (cflag & CSIZE) {
		switch (cflag & CSIZE) {
			case CS5:	buf[6] = 5;	break;
			case CS6:	buf[6] = 6;	break;
			case CS7:	buf[6] = 7;	break;
			default:
			case CS8:	buf[6] = 8;	break;
		}
		dbg("%s - data bits = %d", __FUNCTION__, buf[6]);
	}

	baud = 0;
	switch (cflag & CBAUD) {
		case B0:	baud = 0;	break;
		case B75:	baud = 75;	break;
		case B150:	baud = 150;	break;
		case B300:	baud = 300;	break;
		case B600:	baud = 600;	break;
		case B1200:	baud = 1200;	break;
		case B1800:	baud = 1800;	break;
		case B2400:	baud = 2400;	break;
		case B4800:	baud = 4800;	break;
		case B9600:	baud = 9600;	break;
		case B19200:	baud = 19200;	break;
		case B38400:	baud = 38400;	break;
		case B57600:	baud = 57600;	break;
		case B115200:	baud = 115200;	break;
		case B230400:	baud = 230400;	break;
		case B460800:	baud = 460800;	break;
		default:
			dev_err(&port->dev, "pl2303 driver does not support the baudrate requested (fix it)\n");
			break;
	}
	dbg("%s - baud = %d", __FUNCTION__, baud);
	if (baud) {
		buf[0] = baud & 0xff;
		buf[1] = (baud >> 8) & 0xff;
		buf[2] = (baud >> 16) & 0xff;
		buf[3] = (baud >> 24) & 0xff;
	}

	/* For reference buf[4]=0 is 1 stop bits */
	/* For reference buf[4]=1 is 1.5 stop bits */
	/* For reference buf[4]=2 is 2 stop bits */
	if (cflag & CSTOPB) {
		buf[4] = 2;
		dbg("%s - stop bits = 2", __FUNCTION__);
	} else {
		buf[4] = 0;
		dbg("%s - stop bits = 1", __FUNCTION__);
	}

	if (cflag & PARENB) {
		/* For reference buf[5]=0 is none parity */
		/* For reference buf[5]=1 is odd parity */
		/* For reference buf[5]=2 is even parity */
		/* For reference buf[5]=3 is mark parity */
		/* For reference buf[5]=4 is space parity */
		if (cflag & PARODD) {
			buf[5] = 1;
			dbg("%s - parity = odd", __FUNCTION__);
		} else {
			buf[5] = 2;
			dbg("%s - parity = even", __FUNCTION__);
		}
	} else {
		buf[5] = 0;
		dbg("%s - parity = none", __FUNCTION__);
	}

	i = usb_control_msg (serial->dev, usb_sndctrlpipe (serial->dev, 0),
			     SET_LINE_REQUEST, SET_LINE_REQUEST_TYPE, 
			     0, 0, buf, 7, 100);
	dbg ("0x21:0x20:0:0  %d", i);

	/* change control lines if we are switching to or from B0 */
	spin_lock_irqsave(&priv->lock, flags);
	control = priv->line_control;
	if ((cflag & CBAUD) == B0)
		priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
	else
		priv->line_control |= (CONTROL_DTR | CONTROL_RTS);
	if (control != priv->line_control) {
		control = priv->line_control;
		spin_unlock_irqrestore(&priv->lock, flags);
		set_control_lines(serial->dev, control);
	} else {
		spin_unlock_irqrestore(&priv->lock, flags);
	}
	
	buf[0] = buf[1] = buf[2] = buf[3] = buf[4] = buf[5] = buf[6] = 0;

	i = usb_control_msg (serial->dev, usb_rcvctrlpipe (serial->dev, 0),
			     GET_LINE_REQUEST, GET_LINE_REQUEST_TYPE,
			     0, 0, buf, 7, 100);
	dbg ("0xa1:0x21:0:0  %d - %x %x %x %x %x %x %x", i,
	     buf[0], buf[1], buf[2], buf[3], buf[4], buf[5], buf[6]);

	if (cflag & CRTSCTS) {
		__u16 index;
		if (priv->type == HX)
			index = 0x61;
		else
			index = 0x41;
		i = usb_control_msg(serial->dev, 
				    usb_sndctrlpipe(serial->dev, 0),
				    VENDOR_WRITE_REQUEST,
				    VENDOR_WRITE_REQUEST_TYPE,
				    0x0, index, NULL, 0, 100);
		dbg ("0x40:0x1:0x0:0x%x  %d", index, i);
	}

	kfree (buf);
}

static int pl2303_open (struct usb_serial_port *port, struct file *filp)
{
	struct termios tmp_termios;
	struct usb_serial *serial = port->serial;
	struct pl2303_private *priv = usb_get_serial_port_data(port);
	unsigned char *buf;
	int result;

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

	if (priv->type != HX) {
		usb_clear_halt(serial->dev, port->write_urb->pipe);
		usb_clear_halt(serial->dev, port->read_urb->pipe);
	}

	buf = kmalloc(10, GFP_KERNEL);
	if (buf==NULL)
		return -ENOMEM;

#define FISH(a,b,c,d)								\
	result=usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev,0),	\
			       b, a, c, d, buf, 1, 100);			\
	dbg("0x%x:0x%x:0x%x:0x%x  %d - %x",a,b,c,d,result,buf[0]);

#define SOUP(a,b,c,d)								\
	result=usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev,0),	\
			       b, a, c, d, NULL, 0, 100);			\
	dbg("0x%x:0x%x:0x%x:0x%x  %d",a,b,c,d,result);

	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0x0404, 0);
	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8383, 0);
	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0x0404, 1);
	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8484, 0);
	FISH (VENDOR_READ_REQUEST_TYPE, VENDOR_READ_REQUEST, 0x8383, 0);
	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 0, 1);
	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 1, 0);

	if (priv->type == HX) {
		/* HX chip */
		SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 2, 0x44);
		/* reset upstream data pipes */
          	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 8, 0);
        	SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 9, 0);
	} else {
		SOUP (VENDOR_WRITE_REQUEST_TYPE, VENDOR_WRITE_REQUEST, 2, 0x24);
	}

	kfree(buf);

	/* Setup termios */
	if (port->tty) {
		pl2303_set_termios (port, &tmp_termios);
	}

	//FIXME: need to assert RTS and DTR if CRTSCTS off

	dbg("%s - submitting read urb", __FUNCTION__);
	port->read_urb->dev = serial->dev;
	result = usb_submit_urb (port->read_urb, GFP_KERNEL);
	if (result) {
		dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __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, GFP_KERNEL);
	if (result) {
		dev_err(&port->dev, "%s - failed submitting interrupt urb, error %d\n", __FUNCTION__, result);
		pl2303_close (port, NULL);
		return -EPROTO;
	}
	return 0;
}


static void pl2303_close (struct usb_serial_port *port, struct file *filp)
{
	struct pl2303_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	unsigned int c_cflag;
	int bps;
	long timeout;
	wait_queue_t wait;						\

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

	/* wait for data to drain from the buffer */
	spin_lock_irqsave(&priv->lock, flags);
	timeout = PL2303_CLOSING_WAIT;
	init_waitqueue_entry(&wait, current);
	add_wait_queue(&port->tty->write_wait, &wait);
	for (;;) {
		set_current_state(TASK_INTERRUPTIBLE);
		if (pl2303_buf_data_avail(priv->buf) == 0
		|| timeout == 0 || signal_pending(current)
		|| !usb_get_intfdata(port->serial->interface))	/* disconnect */
			break;
		spin_unlock_irqrestore(&priv->lock, flags);
		timeout = schedule_timeout(timeout);
		spin_lock_irqsave(&priv->lock, flags);
	}
	set_current_state(TASK_RUNNING);
	remove_wait_queue(&port->tty->write_wait, &wait);
	/* clear out any remaining data in the buffer */
	pl2303_buf_clear(priv->buf);
	spin_unlock_irqrestore(&priv->lock, flags);

	/* wait for characters to drain from the device */
	/* (this is long enough for the entire 256 byte */
	/* pl2303 hardware buffer to drain with no flow */
	/* control for data rates of 1200 bps or more, */
	/* for lower rates we should really know how much */
	/* data is in the buffer to compute a delay */
	/* that is not unnecessarily long) */
	bps = tty_get_baud_rate(port->tty);
	if (bps > 1200)
		timeout = max((HZ*2560)/bps,HZ/10);
	else
		timeout = 2*HZ;
	schedule_timeout_interruptible(timeout);

	/* shutdown our urbs */
	dbg("%s - shutting down urbs", __FUNCTION__);
	usb_kill_urb(port->write_urb);
	usb_kill_urb(port->read_urb);
	usb_kill_urb(port->interrupt_in_urb);

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

static int pl2303_tiocmset (struct usb_serial_port *port, struct file *file,
			    unsigned int set, unsigned int clear)
{
	struct pl2303_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	u8 control;

	if (!usb_get_intfdata(port->serial->interface))
		return -ENODEV;

	spin_lock_irqsave (&priv->lock, flags);
	if (set & TIOCM_RTS)
		priv->line_control |= CONTROL_RTS;
	if (set & TIOCM_DTR)
		priv->line_control |= CONTROL_DTR;
	if (clear & TIOCM_RTS)
		priv->line_control &= ~CONTROL_RTS;
	if (clear & TIOCM_DTR)
		priv->line_control &= ~CONTROL_DTR;
	control = priv->line_control;
	spin_unlock_irqrestore (&priv->lock, flags);

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

static int pl2303_tiocmget (struct usb_serial_port *port, struct file *file)
{
	struct pl2303_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	unsigned int mcr;
	unsigned int status;
	unsigned int result;

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

	if (!usb_get_intfdata(port->serial->interface))
		return -ENODEV;

	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);

	return result;
}

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 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;
	struct pl2303_private *priv;

	dbg("%s", __FUNCTION__);

	for (i = 0; i < serial->num_ports; ++i) {
		priv = usb_get_serial_port_data(serial->port[i]);
		if (priv) {
			pl2303_buf_free(priv->buf);