patch-2.3.99-pre4 linux/drivers/usb/serial/ftdi_sio.c

• Lines: 729
• Date: Wed Apr 5 16:58:38 2000
• Orig file: v2.3.99-pre3/linux/drivers/usb/serial/ftdi_sio.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.3.99-pre3/linux/drivers/usb/serial/ftdi_sio.c linux/drivers/usb/serial/ftdi_sio.c
@@ -0,0 +1,728 @@
+/*
+ * USB FTDI SIO driver
+ *
+ * 	(C) Copyright (C) 1999, 2000
+ * 	    Greg Kroah-Hartman (greg@kroah.com)
+ *          Bill Ryder (bryder@sgi.com)
+ *
+ * 	This program is free software; you can redistribute it and/or modify
+ * 	it under the terms of the GNU General Public License as published by
+ * 	the Free Software Foundation; either version 2 of the License, or
+ * 	(at your option) any later version.
+ *
+ * See Documentation/usb/usb-serial.txt for more information on using this driver
+ *
+ * (04/04/2000) Bill Ryder 
+ *         Fixed bugs in TCGET/TCSET ioctls (by removing them - they are 
+ *             handled elsewhere in the serial driver chain).
+ *
+ * (03/30/2000) Bill Ryder 
+ *         Implemented lots of ioctls
+ * 	Fixed a race condition in write
+ * 	Changed some dbg's to errs
+ *
+ * (03/26/2000) gkh
+ * 	Split driver up into device specific pieces.
+ *
+ */
+
+/* Bill Ryder - bryder@sgi.com - wrote the FTDI_SIO implementation */
+/* Thanx to FTDI for so kindly providing details of the protocol required */
+/*   to talk to the device */
+
+
+#include <linux/config.h>
+
+#ifdef CONFIG_USB_SERIAL_FTDI_SIO
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/poll.h>
+#include <linux/init.h>
+#include <linux/malloc.h>
+#include <linux/fcntl.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/tty.h>
+#include <linux/module.h>
+#include <linux/spinlock.h>
+
+#ifdef CONFIG_USB_SERIAL_DEBUG
+	#define DEBUG
+#else
+	#undef DEBUG
+#endif
+#include <linux/usb.h>
+
+#include "usb-serial.h"
+
+#include "ftdi_sio.h"
+
+#define FTDI_VENDOR_ID			0x0403
+#define FTDI_SIO_SERIAL_CONVERTER_ID	0x8372
+
+/* function prototypes for a FTDI serial converter */
+static int  ftdi_sio_startup		(struct usb_serial *serial);
+static int  ftdi_sio_open		(struct usb_serial_port *port, struct file *filp);
+static void ftdi_sio_close		(struct usb_serial_port *port, struct file *filp);
+static int  ftdi_sio_write		(struct usb_serial_port *port, int from_user, const unsigned char *buf, int count);
+static void ftdi_sio_write_bulk_callback (struct urb *urb);
+static void ftdi_sio_read_bulk_callback	(struct urb *urb);
+static void ftdi_sio_set_termios	(struct usb_serial_port *port, struct termios * old);
+static int  ftdi_sio_ioctl		(struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
+
+/* All of the device info needed for the FTDI SIO serial converter */
+static __u16	ftdi_vendor_id		= FTDI_VENDOR_ID;
+static __u16	ftdi_sio_product_id	= FTDI_SIO_SERIAL_CONVERTER_ID;
+struct usb_serial_device_type ftdi_sio_device = {
+	name:			"FTDI SIO",
+	idVendor:		&ftdi_vendor_id,	/* the FTDI vendor ID */
+	idProduct:		&ftdi_sio_product_id,	/* the FTDI SIO product id */
+	needs_interrupt_in:	MUST_HAVE_NOT,		/* this device must not have an interrupt in endpoint */
+	needs_bulk_in:		MUST_HAVE,		/* this device must have a bulk in endpoint */
+	needs_bulk_out:		MUST_HAVE,		/* this device must have a bulk out endpoint */
+	num_interrupt_in:	0,
+	num_bulk_in:		1,
+	num_bulk_out:		1,
+	num_ports:		1,
+	open:			ftdi_sio_open,
+	close:			ftdi_sio_close,
+	write:			ftdi_sio_write,
+	read_bulk_callback:	ftdi_sio_read_bulk_callback,
+	write_bulk_callback:	ftdi_sio_write_bulk_callback,
+	ioctl:			ftdi_sio_ioctl,
+	set_termios:		ftdi_sio_set_termios,
+	startup:		ftdi_sio_startup,
+};
+
+
+/*
+ * ***************************************************************************
+ * FTDI SIO Serial Converter specific driver functions
+ * ***************************************************************************
+ *
+ * Bill Ryder bryder@sgi.com of Silicon Graphics, Inc. did the FTDI_SIO code
+ * Thanx to FTDI for so kindly providing details of the protocol required
+ *   to talk to the device - http://www.ftdi.co.uk
+ *
+ * Tested as at this version - other stuff might work
+ * 23 March 2000
+ *     Works:
+ *      Baudrates - 9600, 38400,19200, 57600, 115200  
+ *      TIOCMBIC - TIOCM_DTR / TIOCM_RTS 
+ *      TIOCMBIS - TIOCM_DTR / TIOCM_RTS 
+ *      TIOCMSET - DTR on/RTSon  / DTR off, RTS off 
+ *      no parity:CS8 even parity:CS7 odd parity:CS7 
+ *      CRTSCTS flow control 
+ *     
+ *      Pilot-xfer zillions of times
+ *  
+ *      cu works with dir option 
+ *
+ *   Not Tested (ie might not work): 
+ *      xon/xoff flow control 
+ *      ppp (modem handling in general) 
+ *
+ *   KNOWN BUGS:
+ *    Multiple Opens
+ *    ==============
+ *      Seems to have problem when opening an already open port, 
+ *      Get I/O error on first attempt, then it lets you in. 
+ *      Need to do proper usage counting - keep registered callbacks for first opener.
+ *     
+ *     Reproduce with: 
+ *       cu -l /dev/ttyUSB0 dir 
+ *       whilst cu is running do:
+ *        stty -a < /dev/ttyUSB0  
+ *
+ *     from stty get: 'bash: /dev/ttyUSB0: Invalid argument ' 
+ *     from cu get 
+ *        write: Invalid argument 
+ *    
+ *    Initialisation Problem
+ *    ======================
+ *    Pilot transfer required me to run the serial_loopback program before it would work.
+ *    Still working on this. See the webpage http://reality.sgi.com/bryder_wellington/ftdi_sio
+ *
+ */
+
+#define WDR_TIMEOUT (HZ * 5 ) /* default urb timeout */
+
+/* do some startup allocations not currently performed by usb_serial_probe() */
+static int ftdi_sio_startup (struct usb_serial *serial)
+{
+	init_waitqueue_head(&serial->write_wait);
+	
+	return (0);
+}
+
+static int  ftdi_sio_open (struct usb_serial_port *port, struct file *filp)
+{ /* ftdi_sio_open */
+	struct termios tmp_termios;
+	struct usb_serial *serial = port->serial;
+	char buf[1]; /* Needed for the usb_control_msg I think */
+
+	dbg("ftdi_sio_open port %d", port->number);
+
+        /* FIXME - multiple concurrent opens cause trouble */
+	if (port->active) {
+		err ("port already open");
+		return -EINVAL;
+	}
+	port->active = 1; /* FIXME - For multiple open this should increment */
+
+	/* See ftdi_sio.h for description of what is reset */
+	usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+			FTDI_SIO_RESET_REQUEST, FTDI_SIO_RESET_REQUEST_TYPE, 
+			FTDI_SIO_RESET_SIO, 
+			0, buf, 0, WDR_TIMEOUT);
+
+	/* Setup termios */
+	port->tty->termios->c_cflag =
+		B9600 | CS8 | CREAD | HUPCL | CLOCAL;
+
+	
+	ftdi_sio_set_termios(port, &tmp_termios);	
+
+	/* 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("error from flowcontrol urb");
+		return(-EINVAL);
+	}	    
+
+	/* Turn on RTS and DTR since we are not flow controlling*/
+	if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+			    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+			    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+			    (unsigned)FTDI_SIO_SET_DTR_HIGH, 0, 
+			    buf, 0, WDR_TIMEOUT) < 0) {
+		err("Error from DTR HIGH urb");
+	}
+	if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+			    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+			    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+			    (unsigned)FTDI_SIO_SET_RTS_HIGH, 0, 
+			    buf, 0, WDR_TIMEOUT) < 0) {
+		err("Error from RTS HIGH urb");
+	}
+	
+	/*Start reading from the device*/
+	if (usb_submit_urb(port->read_urb))
+		err("usb_submit_urb(read bulk) failed");
+
+	return (0);
+} /* ftdi_sio_open */
+
+
+static void ftdi_sio_close (struct usb_serial_port *port, struct file *filp)
+{ /* ftdi_sio_close */
+	struct usb_serial *serial = port->serial;
+	unsigned int c_cflag = port->tty->termios->c_cflag;
+	char buf[1];
+
+	dbg("ftdi_sio_close port %d", port->number);
+	
+	if (c_cflag & HUPCL){
+		/* 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("error from flowcontrol urb");
+		}	    
+
+		/* drop DTR */
+ 		if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+				    (unsigned)FTDI_SIO_SET_DTR_LOW, 0, 
+				    buf, 0, WDR_TIMEOUT) < 0) {
+			err("Error from DTR LOW urb");
+		}
+		/* drop RTS */
+		if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+				    (unsigned)FTDI_SIO_SET_RTS_LOW, 0, 
+				    buf, 0, WDR_TIMEOUT) < 0) {
+			err("Error from RTS LOW urb");
+		}	
+	}
+
+	/* shutdown our bulk reads and writes */
+	usb_unlink_urb (port->write_urb);
+	usb_unlink_urb (port->read_urb);
+	port->active = 0;
+} /* ftdi_sio_close */
+
+
+  
+/* The ftdi_sio requires the first byte to have:
+ *  B0 1
+ *  B1 0
+ *  B2..7 length of message excluding byte 0
+ */
+static int ftdi_sio_write (struct usb_serial_port *port, int from_user, 
+			   const unsigned char *buf, int count)
+{ /* ftdi_sio_write */
+	struct usb_serial *serial = port->serial;
+	const int data_offset = 1;
+	int rc; 
+	DECLARE_WAITQUEUE(wait, current);
+	
+	dbg("ftdi_sio_serial_write port %d, %d bytes", port->number, count);
+
+	if (count == 0) {
+		err("write request of 0 bytes");
+		return 0;
+	}
+
+	/* only do something if we have a bulk out endpoint */
+	if (serial->num_bulk_out) {
+		unsigned char *first_byte = port->write_urb->transfer_buffer;
+
+		/* Was seeing a race here, got a read callback, then write callback before
+		   hitting interuptible_sleep_on  - so wrapping in add_wait_queue stuff */
+
+		add_wait_queue(&serial->write_wait, &wait);
+		set_current_state (TASK_INTERRUPTIBLE);
+		while (port->write_urb->status == -EINPROGRESS) {
+			dbg("ftdi_sio - write in progress - retrying");
+			if (0 /* file->f_flags & O_NONBLOCK */) {
+				rc = -EAGAIN;
+				goto err;
+			}
+			if (signal_pending(current)) {
+				current->state = TASK_RUNNING;
+				remove_wait_queue(&serial->write_wait, &wait);				
+				rc = -ERESTARTSYS;
+				goto err;
+			}
+			schedule();
+		}		
+		remove_wait_queue(&serial->write_wait, &wait);
+		set_current_state(TASK_RUNNING);
+
+		count += data_offset;
+		count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
+		if (count == 0) {
+			return 0;
+		}
+
+		/* Copy in the data to send */
+		if (from_user) {
+			copy_from_user(port->write_urb->transfer_buffer + data_offset , 
+				       buf, count - data_offset );
+		}
+		else {
+			memcpy(port->write_urb->transfer_buffer + data_offset,
+			       buf, count - data_offset );
+		}  
+
+		/* Write the control byte at the front of the packet*/
+		first_byte = port->write_urb->transfer_buffer;
+		*first_byte = 1 | ((count-data_offset) << 2) ; 
+
+#ifdef CONFIG_USB_SERIAL_DEBUG
+		dbg("Bytes: %d, Control Byte: 0o%03o",count, first_byte[0]);
+
+		if (count) {
+			int i;
+			printk (KERN_DEBUG __FILE__ ": data written - length = %d, data = ", count);
+			for (i = 0; i < count; ++i) {
+				printk ( "0x%02x ", first_byte[i]);
+				if (first_byte[i] > ' ' && first_byte[i] < '~') {
+					printk( "%c ", first_byte[i]);
+				} else {
+					printk( "  ");
+				}
+			}
+
+		     
+			printk ( "\n");
+		}
+
+#endif
+		/* send the data out the bulk port */
+		port->write_urb->transfer_buffer_length = count;
+
+		if (usb_submit_urb(port->write_urb))
+			err("usb_submit_urb(write bulk) failed");
+
+		dbg("write returning: %d", count - data_offset);
+		return (count - data_offset);
+	}
+	
+	/* no bulk out, so return 0 bytes written */
+	return 0;
+ err: /* error exit */
+	return(rc);
+} /* ftdi_sio_write */
+
+static void ftdi_sio_write_bulk_callback (struct urb *urb)
+{
+	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
+	struct usb_serial *serial;
+       	struct tty_struct *tty = port->tty;
+
+	dbg("ftdi_sio_write_bulk_callback");
+
+	if (port_paranoia_check (port, "ftdi_sio_write_bulk_callback")) {
+		return;
+	}
+
+	serial = port->serial;
+	if (serial_paranoia_check (serial, "ftdi_sio_write_bulk_callback")) {
+		return;
+	}
+	
+	if (urb->status) {
+		dbg("nonzero write bulk status received: %d", urb->status);
+		return;
+	}
+
+	wake_up_interruptible(&serial->write_wait);
+	if ((tty->flags & (1 << TTY_DO_WRITE_WAKEUP)) && tty->ldisc.write_wakeup)
+		(tty->ldisc.write_wakeup)(tty);
+
+	wake_up_interruptible(&tty->write_wait);
+	
+	return;
+} /* ftdi_sio_write_bulk_callback */
+
+static void ftdi_sio_read_bulk_callback (struct urb *urb)
+{ /* ftdi_sio_serial_buld_callback */
+	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
+	struct usb_serial *serial;
+       	struct tty_struct *tty = port->tty ;
+       	unsigned char *data = urb->transfer_buffer;
+
+	const int data_offset = 2;
+	int i;
+
+	dbg("ftdi_sio read callback");
+
+	if (port_paranoia_check (port, "ftdi_sio_read_bulk_callback")) {
+		return;
+	}
+
+	serial = port->serial;
+	if (serial_paranoia_check (serial, "ftdi_sio_read_bulk_callback")) {
+		return;
+	}
+	
+	/* TO DO -- check for hung up line and handle appropriately: */
+	/*   send hangup (need to find out how to do this) */
+ 
+
+	if (urb->status) {
+		/* This will happen at close every time so it is a dbg not an err */
+		dbg("nonzero read bulk status received: %d", urb->status);
+		return;
+	}
+
+#ifdef CONFIG_USB_SERIAL_DEBUG
+	if (urb->actual_length > 2) {
+		printk (KERN_DEBUG __FILE__ ": data read - length = %d, data = ", urb->actual_length);
+		for (i = 0; i < urb->actual_length; ++i) {
+			printk ( "0x%.2x ", data[i]);
+			if (data[i] > ' ' && data[i] < '~') {
+				printk( "%c ", data[i]);
+			} else {
+				printk( "  ");
+			}
+		}
+		printk ( "\n");
+	} else {
+                dbg("Just status");
+        }
+#endif
+	
+
+	if (urb->actual_length > data_offset) {
+		for (i = data_offset ; i < urb->actual_length ; ++i) {
+			tty_insert_flip_char(tty, data[i], 0);
+	  	}
+	  	tty_flip_buffer_push(tty);
+	}
+
+	/* Continue trying to always read  */
+	if (usb_submit_urb(urb))
+		err("failed resubmitting read urb");
+
+	return;
+} /* ftdi_sio_serial_read_bulk_callback */
+
+/* As I understand this - 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_sio_set_termios (struct usb_serial_port *port, struct termios *old_termios)
+{ /* ftdi_sio_set_termios */
+	struct usb_serial *serial = port->serial;
+	unsigned int cflag = port->tty->termios->c_cflag;
+	__u16 urb_value; /* Will hold the new flags */
+	char buf[1]; /* Perhaps I should dynamically alloc this? */
+	
+	dbg("ftdi_sio_set_termios port %d", port->number);
+
+
+	/* 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");
+		}
+	}
+	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("FAILED to set databits/stopbits/parity");
+	}	   
+
+	/* Now do the baudrate */
+
+	switch(cflag & CBAUD){
+	case B0: break; /* Handled below */
+	case B300: urb_value = ftdi_sio_b300; dbg("Set to 300"); break;
+	case B600: urb_value = ftdi_sio_b600; dbg("Set to 600") ; break;
+	case B1200: urb_value = ftdi_sio_b1200; dbg("Set to 1200") ; break;
+	case B2400: urb_value = ftdi_sio_b2400; dbg("Set to 2400") ; break;
+	case B4800: urb_value = ftdi_sio_b4800; dbg("Set to 4800") ; break;
+	case B9600: urb_value = ftdi_sio_b9600; dbg("Set to 9600") ; break;
+	case B19200: urb_value = ftdi_sio_b19200; dbg("Set to 19200") ; break;
+	case B38400: urb_value = ftdi_sio_b38400; dbg("Set to 38400") ; break;
+	case B57600: urb_value = ftdi_sio_b57600; dbg("Set to 57600") ; break;
+	case B115200: urb_value = ftdi_sio_b115200; dbg("Set to 115200") ; break;
+	default: dbg("FTDI_SIO does not support the baudrate requested"); 
+		/* FIXME - how to return an error for this? */ break;
+	}
+	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("error from disable flowcontrol urb");
+		}	    
+		/* Drop RTS and DTR */
+		if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+				    (unsigned)FTDI_SIO_SET_DTR_LOW, 0, 
+				    buf, 0, WDR_TIMEOUT) < 0) {
+			err("Error from DTR LOW urb");
+		}
+		if (usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+				    (unsigned)FTDI_SIO_SET_RTS_LOW, 0, 
+				    buf, 0, WDR_TIMEOUT) < 0) {
+			err("Error from RTS LOW urb");
+		}	
+		
+	} else {
+		if (usb_control_msg(serial->dev, 
+				    usb_sndctrlpipe(serial->dev, 0),
+				    FTDI_SIO_SET_BAUDRATE_REQUEST, 
+				    FTDI_SIO_SET_BAUDRATE_REQUEST_TYPE,
+				    urb_value, 0, 
+				    buf, 0, 100) < 0) {
+			err("urb failed to set baurdrate");
+		}
+	}
+	/* Set flow control */
+	/* Note device also supports DTR/CD (ugh) and Xon/Xoff in hardware */
+	if (cflag & CRTSCTS) {
+		dbg("Setting to CRTSCTS 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 , FTDI_SIO_RTS_CTS_HS,
+				    buf, 0, WDR_TIMEOUT) < 0) {
+			err("urb failed to set to rts/cts flow control");
+		}		
+		
+	} else { 
+		/* CHECK Assuming XON/XOFF handled by stack - not by device */
+		/* Disable flow control */
+		dbg("Turning off hardware 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("urb failed to clear flow control");
+		}				
+		
+	}
+	return;
+} /* ftdi_sio_set_termios */
+
+static int ftdi_sio_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
+{
+	struct usb_serial *serial = port->serial;
+	__u16 urb_value=0; /* Will hold the new flags */
+	char buf[1];
+	int  ret, mask;
+	
+	dbg("ftdi_sio_ioctl - cmd 0x%04x", cmd);
+
+	/* Based on code from acm.c and others */
+	switch (cmd) {
+
+	case TIOCMGET:
+		dbg("TIOCMGET");
+		/* 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, HZ * 5)) < 0 ) {
+			dbg("Get not get modem status of device");
+			return(ret);
+		}
+
+		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("TIOCMSET");
+		if ((ret = get_user(mask, (unsigned long *) arg))) return ret;
+		urb_value = ((mask & TIOCM_DTR) ? FTDI_SIO_SET_DTR_HIGH : FTDI_SIO_SET_DTR_LOW);
+		if ((ret = usb_control_msg(serial->dev, 
+				    usb_sndctrlpipe(serial->dev, 0),
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+				    urb_value , 0,
+				    buf, 0, WDR_TIMEOUT)) < 0){
+			err("Urb to set DTR failed");
+			return(ret);
+		}
+		urb_value = ((mask & TIOCM_RTS) ? FTDI_SIO_SET_RTS_HIGH : FTDI_SIO_SET_RTS_LOW);
+		if ((ret = usb_control_msg(serial->dev, 
+				    usb_sndctrlpipe(serial->dev, 0),
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+				    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+				    urb_value , 0,
+				    buf, 0, WDR_TIMEOUT)) < 0){
+			err("Urb to set RTS failed");
+			return(ret);
+		}
+		break;
+					
+	case TIOCMBIS: /* turns on (Sets) the lines as specified by the mask */
+		dbg("TIOCMBIS");
+ 	        if ((ret = get_user(mask, (unsigned long *) arg))) return ret;
+  	        if (mask & TIOCM_DTR){
+			if ((ret = usb_control_msg(serial->dev, 
+					    usb_sndctrlpipe(serial->dev, 0),
+					    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+					    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+					    FTDI_SIO_SET_DTR_HIGH , 0,
+					    buf, 0, WDR_TIMEOUT)) < 0){
+				err("Urb to set DTR failed");
+				return(ret);
+				}
+			}
+			if (mask & TIOCM_RTS) {
+			if ((ret = usb_control_msg(serial->dev, 
+					    usb_sndctrlpipe(serial->dev, 0),
+					    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+					    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+					    FTDI_SIO_SET_RTS_HIGH , 0,
+					    buf, 0, WDR_TIMEOUT)) < 0){
+				err("Urb to set RTS failed");
+				return(ret);
+			}
+		}
+					break;
+
+	case TIOCMBIC: /* turns off (Clears) the lines as specified by the mask */
+		dbg("TIOCMBIC");
+ 	        if ((ret = get_user(mask, (unsigned long *) arg))) return ret;
+  	        if (mask & TIOCM_DTR){
+			if ((ret = usb_control_msg(serial->dev, 
+					    usb_sndctrlpipe(serial->dev, 0),
+					    FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+					    FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+					    FTDI_SIO_SET_DTR_LOW , 0,
+					    buf, 0, WDR_TIMEOUT)) < 0){
+				err("Urb to unset DTR failed");
+				return(ret);
+			}
+		}	
+		if (mask & TIOCM_RTS) {
+			if ((ret = usb_control_msg(serial->dev, 
+					       usb_sndctrlpipe(serial->dev, 0),
+					       FTDI_SIO_SET_MODEM_CTRL_REQUEST, 
+					       FTDI_SIO_SET_MODEM_CTRL_REQUEST_TYPE,
+					    FTDI_SIO_SET_RTS_LOW , 0,
+					    buf, 0, WDR_TIMEOUT)) < 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. 
+		 *
+		 */
+
+	default:
+	  /* This is not an error - turns out the higher layers will do 
+	   *  some ioctls itself (see comment above)
+ 	   */
+		dbg("ftdi_sio ioctl arg not supported - it was 0x%04x",cmd);
+		return(-ENOIOCTLCMD);
+		break;
+	}
+	dbg("ftdi_sio_ioctl returning 0");
+	return 0;
+} /* ftdi_sio_ioctl */
+
+#endif 	/* CONFIG_USB_SERIAL_FTDI_SIO */
+
+