ftdi_sio.c

linux2.4.20下的针对三星公司的s3c2410的usb模块驱动代码

		for (i = data_offset ; i < urb->actual_length ; ++i) {
			/* have to make sure we don't overflow the buffer
			  with tty_insert_flip_char's */
			if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
				tty_flip_buffer_push(tty);
			}
			/* Note that the error flag is duplicated for 
			   every character received since we don't know
			   which character it applied to */
			tty_insert_flip_char(tty, data[i], error_flag);
		}
	  	tty_flip_buffer_push(tty);


	} 

#ifdef NOT_CORRECT_BUT_KEEPING_IT_FOR_NOW
	/* if a parity error is detected you get status packets forever
	   until a character is sent without a parity error.
	   This doesn't work well since the application receives a never
	   ending stream of bad data - even though new data hasn't been sent.
	   Therefore I (bill) have taken this out.
	   However - this might make sense for framing errors and so on 
	   so I am leaving the code in for now.
	*/
      else {
		if (error_flag != TTY_NORMAL){
			dbg("error_flag is not normal");
				/* In this case it is just status - if that is an error send a bad character */
				if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
					tty_flip_buffer_push(tty);
				}
				tty_insert_flip_char(tty, 0xff, error_flag);
				tty_flip_buffer_push(tty);
		}
	}
#endif

	/* Continue trying to always read  */
	FILL_BULK_URB(port->read_urb, serial->dev, 
		      usb_rcvbulkpipe(serial->dev, port->bulk_in_endpointAddress),
		      port->read_urb->transfer_buffer, port->read_urb->transfer_buffer_length,
		      ftdi_read_bulk_callback, port);

	result = usb_submit_urb(port->read_urb);
	if (result)
		err("%s - failed resubmitting read urb, error %d", __FUNCTION__, result);

	return;
} /* ftdi_read_bulk_callback */


static void ftdi_break_ctl( struct usb_serial_port *port, int break_state )
{
	struct usb_serial *serial = port->serial;
	struct ftdi_private *priv = (struct ftdi_private *)port->private;
	__u16 urb_value = 0; 
	char buf[1];
	
	/* break_state = -1 to turn on break, and 0 to turn off break */
	/* see drivers/char/tty_io.c to see it used */
	/* last_set_data_urb_value NEVER has the break bit set in it */

	if (break_state) {
		urb_value = priv->last_set_data_urb_value | FTDI_SIO_SET_BREAK;
	} else {
		urb_value = priv->last_set_data_urb_value; 
	}

	
	if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
			    FTDI_SIO_SET_DATA_REQUEST, 
			    FTDI_SIO_SET_DATA_REQUEST_TYPE,
			    urb_value , 0,
			    buf, 0, WDR_TIMEOUT) < 0) {
		err("%s FAILED to enable/disable break state (state was %d)", __FUNCTION__,break_state);
	}	   

	dbg("%s break state is %d - urb is %d", __FUNCTION__,break_state, urb_value);
	
}


/* old_termios contains the original termios settings and tty->termios contains
 * the new setting to be used
 * WARNING: set_termios calls this with old_termios in kernel space
 */

static void ftdi_set_termios (struct usb_serial_port *port, struct termios *old_termios)
{ /* ftdi_termios */
	struct usb_serial *serial = port->serial;
	unsigned int cflag = port->tty->termios->c_cflag;
	struct ftdi_private *priv = (struct ftdi_private *)port->private;	
	__u16 urb_value; /* will hold the new flags */
	char buf[1]; /* Perhaps I should dynamically alloc this? */
	
	
	dbg("%s", __FUNCTION__);


	/* FIXME -For this cut I don't care if the line is really changing or 
	   not  - so just do the change regardless  - should be able to 
	   compare old_termios and tty->termios */
	/* NOTE These routines can get interrupted by 
	   ftdi_sio_read_bulk_callback  - need to examine what this 
           means - don't see any problems yet */
	
	/* Set number of data bits, parity, stop bits */
	
	urb_value = 0;
	urb_value |= (cflag & CSTOPB ? FTDI_SIO_SET_DATA_STOP_BITS_2 :
		      FTDI_SIO_SET_DATA_STOP_BITS_1);
	urb_value |= (cflag & PARENB ? 
		      (cflag & PARODD ? FTDI_SIO_SET_DATA_PARITY_ODD : 
		       FTDI_SIO_SET_DATA_PARITY_EVEN) :
		      FTDI_SIO_SET_DATA_PARITY_NONE);
	if (cflag & CSIZE) {
		switch (cflag & CSIZE) {
		case CS5: urb_value |= 5; dbg("Setting CS5"); break;
		case CS6: urb_value |= 6; dbg("Setting CS6"); break;
		case CS7: urb_value |= 7; dbg("Setting CS7"); break;
		case CS8: urb_value |= 8; dbg("Setting CS8"); break;
		default:
			err("CSIZE was set but not CS5-CS8");
		}
	}

	/* This is needed by the break command since it uses the same command - but is
	 *  or'ed with this value  */
	priv->last_set_data_urb_value = urb_value;
	
	if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
			    FTDI_SIO_SET_DATA_REQUEST, 
			    FTDI_SIO_SET_DATA_REQUEST_TYPE,
			    urb_value , 0,
			    buf, 0, 100) < 0) {
		err("%s FAILED to set databits/stopbits/parity", __FUNCTION__);
	}	   

	/* Now do the baudrate */
	if ((cflag & CBAUD) == B0 ) {
		/* Disable flow control */
		if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
				    FTDI_SIO_SET_FLOW_CTRL_REQUEST, 
				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
				    0, 0, 
				    buf, 0, WDR_TIMEOUT) < 0) {
			err("%s error from disable flowcontrol urb", __FUNCTION__);
		}	    
		/* Drop RTS and DTR */
		if (set_dtr(serial->dev, usb_sndctrlpipe(serial->dev, 0),LOW) < 0){
			err("%s Error from DTR LOW urb", __FUNCTION__);
		}
		if (set_rts(serial->dev, usb_sndctrlpipe(serial->dev, 0),LOW) < 0){
			err("%s Error from RTS LOW urb", __FUNCTION__);
		}	
		
	} else {
		/* set the baudrate determined before */
		if (change_speed(port)) {
			err("%s urb failed to set baurdrate", __FUNCTION__);
		}
	}

	/* Set flow control */
	/* Note device also supports DTR/CD (ugh) and Xon/Xoff in hardware */
	if (cflag & CRTSCTS) {
		dbg("%s Setting to CRTSCTS flow control", __FUNCTION__);
		if (usb_control_msg(serial->dev, 
				    usb_sndctrlpipe(serial->dev, 0),
				    FTDI_SIO_SET_FLOW_CTRL_REQUEST, 
				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
				    0 , FTDI_SIO_RTS_CTS_HS,
				    buf, 0, WDR_TIMEOUT) < 0) {
			err("urb failed to set to rts/cts flow control");
		}		
		
	} else { 
		/* CHECKME Assuming XON/XOFF handled by tty stack - not by device */
		dbg("%s Turning off hardware flow control", __FUNCTION__);
		if (usb_control_msg(serial->dev, 
				    usb_sndctrlpipe(serial->dev, 0),
				    FTDI_SIO_SET_FLOW_CTRL_REQUEST, 
				    FTDI_SIO_SET_FLOW_CTRL_REQUEST_TYPE,
				    0, 0, 
				    buf, 0, WDR_TIMEOUT) < 0) {
			err("urb failed to clear flow control");
		}				
		
	}
	return;
} /* ftdi_termios */


static int ftdi_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
{
	struct usb_serial *serial = port->serial;
	struct ftdi_private *priv = (struct ftdi_private *)port->private;

	__u16 urb_value=0; /* Will hold the new flags */
	char buf[2];
	int  ret, mask;
	
	dbg("%s cmd 0x%04x", __FUNCTION__, cmd);

	/* Based on code from acm.c and others */
	switch (cmd) {

	case TIOCMGET:
		dbg("%s TIOCMGET", __FUNCTION__);
		switch (priv->chip_type) {
		case SIO:
			/* Request the status from the device */
			if ((ret = usb_control_msg(serial->dev, 
						   usb_rcvctrlpipe(serial->dev, 0),
						   FTDI_SIO_GET_MODEM_STATUS_REQUEST, 
						   FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
						   0, 0, 
						   buf, 1, WDR_TIMEOUT)) < 0 ) {
				err("%s Could not get modem status of device - err: %d", __FUNCTION__,
				    ret);
				return(ret);
			}
			break;
		case FT8U232AM:
			/* the 8U232AM returns a two byte value (the sio is a 1 byte value) - in the same
			   format as the data returned from the in point */
			if ((ret = usb_control_msg(serial->dev, 
						   usb_rcvctrlpipe(serial->dev, 0),
						   FTDI_SIO_GET_MODEM_STATUS_REQUEST, 
						   FTDI_SIO_GET_MODEM_STATUS_REQUEST_TYPE,
						   0, 0, 
						   buf, 2, WDR_TIMEOUT)) < 0 ) {
				err("%s Could not get modem status of device - err: %d", __FUNCTION__,
				    ret);
				return(ret);
			}
			break;
		default:
			return -EFAULT;
			break;
		}

		return put_user((buf[0] & FTDI_SIO_DSR_MASK ? TIOCM_DSR : 0) |
				(buf[0] & FTDI_SIO_CTS_MASK ? TIOCM_CTS : 0) |
				(buf[0]  & FTDI_SIO_RI_MASK  ? TIOCM_RI  : 0) |
				(buf[0]  & FTDI_SIO_RLSD_MASK ? TIOCM_CD  : 0),
				(unsigned long *) arg);
		break;

	case TIOCMSET: /* Turns on and off the lines as specified by the mask */
		dbg("%s TIOCMSET", __FUNCTION__);
		if (get_user(mask, (unsigned long *) arg))
			return -EFAULT;
		urb_value = ((mask & TIOCM_DTR) ? HIGH : LOW);
		if (set_dtr(serial->dev, usb_sndctrlpipe(serial->dev, 0),urb_value) < 0){
			err("Error from DTR set urb (TIOCMSET)");
		}
		urb_value = ((mask & TIOCM_RTS) ? HIGH : LOW);
		if (set_rts(serial->dev, usb_sndctrlpipe(serial->dev, 0),urb_value) < 0){
			err("Error from RTS set urb (TIOCMSET)");
		}	
		break;
					
	case TIOCMBIS: /* turns on (Sets) the lines as specified by the mask */
		dbg("%s TIOCMBIS", __FUNCTION__);
 	        if (get_user(mask, (unsigned long *) arg))
			return -EFAULT;
  	        if (mask & TIOCM_DTR){
			if ((ret = set_dtr(serial->dev, 
					   usb_sndctrlpipe(serial->dev, 0),
					   HIGH)) < 0) {
				err("Urb to set DTR failed");
				return(ret);
			}
		}
		if (mask & TIOCM_RTS) {
			if ((ret = set_rts(serial->dev, 
					   usb_sndctrlpipe(serial->dev, 0),
					   HIGH)) < 0){
				err("Urb to set RTS failed");
				return(ret);
			}
		}
					break;

	case TIOCMBIC: /* turns off (Clears) the lines as specified by the mask */
		dbg("%s TIOCMBIC", __FUNCTION__);
 	        if (get_user(mask, (unsigned long *) arg))
			return -EFAULT;
  	        if (mask & TIOCM_DTR){
			if ((ret = set_dtr(serial->dev, 
					   usb_sndctrlpipe(serial->dev, 0),
					   LOW)) < 0){
				err("Urb to unset DTR failed");
				return(ret);
			}
		}	
		if (mask & TIOCM_RTS) {
			if ((ret = set_rts(serial->dev, 
					   usb_sndctrlpipe(serial->dev, 0),
					   LOW)) < 0){
				err("Urb to unset RTS failed");
				return(ret);
			}
		}
		break;

		/*
		 * I had originally implemented TCSET{A,S}{,F,W} and
		 * TCGET{A,S} here separately, however when testing I
		 * found that the higher layers actually do the termios
		 * conversions themselves and pass the call onto
		 * ftdi_sio_set_termios. 
		 *
		 */

	case TIOCGSERIAL: /* gets serial port data */
		return get_serial_info(port, (struct serial_struct *) arg);

	case TIOCSSERIAL: /* sets serial port data */
		return set_serial_info(port, (struct serial_struct *) arg);

	/*
	 * Wait for any of the 4 modem inputs (DCD,RI,DSR,CTS) to change
	 * - mask passed in arg for lines of interest
	 *   (use |'ed TIOCM_RNG/DSR/CD/CTS for masking)
	 * Caller should use TIOCGICOUNT to see which one it was.
	 *
	 * This code is borrowed from linux/drivers/char/serial.c
	 */
	case TIOCMIWAIT:
		while (priv != NULL) {
			interruptible_sleep_on(&priv->delta_msr_wait);
			/* see if a signal did it */
			if (signal_pending(current))
				return -ERESTARTSYS;
			else {
				char diff = priv->diff_status;

				if (diff == 0) {
					return -EIO; /* no change => error */
				}

				/* Consume all events */
				priv->diff_status = 0;

				/* Return 0 if caller wanted to know about these bits */
				if ( ((arg & TIOCM_RNG) && (diff & FTDI_RS0_RI)) ||
				     ((arg & TIOCM_DSR) && (diff & FTDI_RS0_DSR)) ||
				     ((arg & TIOCM_CD)  && (diff & FTDI_RS0_RLSD)) ||
				     ((arg & TIOCM_CTS) && (diff & FTDI_RS0_CTS)) ) {
					return 0;
				}
				/*
				 * Otherwise caller can't care less about what happened,
				 * and so we continue to wait for more events.
				 */
			}
		}
		/* NOTREACHED */

	default:
	  /* This is not an error - turns out the higher layers will do 
	   *  some ioctls itself (see comment above)
 	   */
		dbg("%s arg not supported - it was 0x%04x", __FUNCTION__,cmd);
		return(-ENOIOCTLCMD);
		break;
	}
	return 0;
} /* ftdi_ioctl */


static int __init ftdi_init (void)
{
	dbg("%s", __FUNCTION__);
	usb_serial_register (&ftdi_SIO_device);
	usb_serial_register (&ftdi_8U232AM_device);
	info(DRIVER_VERSION ":" DRIVER_DESC);
	return 0;
}


static void __exit ftdi_exit (void)
{
	dbg("%s", __FUNCTION__);
	usb_serial_deregister (&ftdi_SIO_device);
	usb_serial_deregister (&ftdi_8U232AM_device);
}


module_init(ftdi_init);
module_exit(ftdi_exit);

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

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