drivers/usb/serial/cp2101.c - kernel/msm-5.4 - Gitiles

 /*
  * Silicon Laboratories CP2101/CP2102 USB to RS232 serial adaptor driver
  *
  * Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
  *
  *	This program is free software; you can redistribute it and/or
  *	modify it under the terms of the GNU General Public License version
  *	2 as published by the Free Software Foundation.
  *
  * Support to set flow control line levels using TIOCMGET and TIOCMSET
  * thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
  * control thanks to Munir Nassar nassarmu@real-time.com
  *
  * Outstanding Issues:
  *  Buffers are not flushed when the port is opened.
  *  Multiple calls to write() may fail with "Resource temporarily unavailable"
  *
  */

 #include <linux/kernel.h>
 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/usb.h>
 #include <asm/uaccess.h>
 #include <linux/usb/serial.h>

 /*
  * Version Information
  */
 #define DRIVER_VERSION "v0.07"
 #define DRIVER_DESC "Silicon Labs CP2101/CP2102 RS232 serial adaptor driver"

 /*
  * Function Prototypes
  */
 static int cp2101_open(struct usb_serial_port*, struct file*);
 static void cp2101_cleanup(struct usb_serial_port*);
 static void cp2101_close(struct usb_serial_port*, struct file*);
 static void cp2101_get_termios(struct usb_serial_port*);
 static void cp2101_set_termios(struct usb_serial_port*, struct ktermios*);
 static int cp2101_tiocmget (struct usb_serial_port *, struct file *);
 static int cp2101_tiocmset (struct usb_serial_port *, struct file *,
 		unsigned int, unsigned int);
 static void cp2101_break_ctl(struct usb_serial_port*, int);
 static int cp2101_startup (struct usb_serial *);
 static void cp2101_shutdown(struct usb_serial*);


 static int debug;

 static struct usb_device_id id_table [] = {
 	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
 	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
 	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
 	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
 	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
 	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
 	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
 	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
 	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
 	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
 	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
 	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
 	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
 	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
 	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
 	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
 	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
 	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
 	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
 	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
 	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
 	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
 	{ USB_DEVICE(0x10c4, 0x8293) }, /* Telegesys ETRX2USB */
 	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
 	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
 	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
 	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
 	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
 	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
 	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
 	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
 	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
 	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
 	{ } /* Terminating Entry */
 };

 MODULE_DEVICE_TABLE (usb, id_table);

 static struct usb_driver cp2101_driver = {
 	.name		= "cp2101",
 	.probe		= usb_serial_probe,
 	.disconnect	= usb_serial_disconnect,
 	.id_table	= id_table,
 	.no_dynamic_id	= 	1,
 };

 static struct usb_serial_driver cp2101_device = {
 	.driver = {
 		.owner =	THIS_MODULE,
 		.name = 	"cp2101",
 	},
 	.usb_driver		= &cp2101_driver,
 	.id_table		= id_table,
 	.num_interrupt_in	= 0,
 	.num_bulk_in		= NUM_DONT_CARE,
 	.num_bulk_out		= NUM_DONT_CARE,
 	.num_ports		= 1,
 	.open			= cp2101_open,
 	.close			= cp2101_close,
 	.break_ctl		= cp2101_break_ctl,
 	.set_termios		= cp2101_set_termios,
 	.tiocmget 		= cp2101_tiocmget,
 	.tiocmset		= cp2101_tiocmset,
 	.attach			= cp2101_startup,
 	.shutdown		= cp2101_shutdown,
 };

 /* Config request types */
 #define REQTYPE_HOST_TO_DEVICE	0x41
 #define REQTYPE_DEVICE_TO_HOST	0xc1

 /* Config SET requests. To GET, add 1 to the request number */
 #define CP2101_UART 		0x00	/* Enable / Disable */
 #define CP2101_BAUDRATE		0x01	/* (BAUD_RATE_GEN_FREQ / baudrate) */
 #define CP2101_BITS		0x03	/* 0x(0)(databits)(parity)(stopbits) */
 #define CP2101_BREAK		0x05	/* On / Off */
 #define CP2101_CONTROL		0x07	/* Flow control line states */
 #define CP2101_MODEMCTL		0x13	/* Modem controls */
 #define CP2101_CONFIG_6		0x19	/* 6 bytes of config data ??? */

 /* CP2101_UART */
 #define UART_ENABLE		0x0001
 #define UART_DISABLE		0x0000

 /* CP2101_BAUDRATE */
 #define BAUD_RATE_GEN_FREQ	0x384000

 /* CP2101_BITS */
 #define BITS_DATA_MASK		0X0f00
 #define BITS_DATA_5		0X0500
 #define BITS_DATA_6		0X0600
 #define BITS_DATA_7		0X0700
 #define BITS_DATA_8		0X0800
 #define BITS_DATA_9		0X0900

 #define BITS_PARITY_MASK	0x00f0
 #define BITS_PARITY_NONE	0x0000
 #define BITS_PARITY_ODD		0x0010
 #define BITS_PARITY_EVEN	0x0020
 #define BITS_PARITY_MARK	0x0030
 #define BITS_PARITY_SPACE	0x0040

 #define BITS_STOP_MASK		0x000f
 #define BITS_STOP_1		0x0000
 #define BITS_STOP_1_5		0x0001
 #define BITS_STOP_2		0x0002

 /* CP2101_BREAK */
 #define BREAK_ON		0x0000
 #define BREAK_OFF		0x0001

 /* CP2101_CONTROL */
 #define CONTROL_DTR		0x0001
 #define CONTROL_RTS		0x0002
 #define CONTROL_CTS		0x0010
 #define CONTROL_DSR		0x0020
 #define CONTROL_RING		0x0040
 #define CONTROL_DCD		0x0080
 #define CONTROL_WRITE_DTR	0x0100
 #define CONTROL_WRITE_RTS	0x0200

 /*
  * cp2101_get_config
  * Reads from the CP2101 configuration registers
  * 'size' is specified in bytes.
  * 'data' is a pointer to a pre-allocated array of integers large
  * enough to hold 'size' bytes (with 4 bytes to each integer)
  */
 static int cp2101_get_config(struct usb_serial_port* port, u8 request,
 		unsigned int *data, int size)
 {
 	struct usb_serial *serial = port->serial;
 	__le32 *buf;
 	int result, i, length;

 	/* Number of integers required to contain the array */
 	length = (((size - 1) | 3) + 1)/4;

 	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
 	if (!buf) {
 		dev_err(&port->dev, "%s - out of memory.\n", __FUNCTION__);
 		return -ENOMEM;
 	}

 	/* For get requests, the request number must be incremented */
 	request++;

 	/* Issue the request, attempting to read 'size' bytes */
 	result = usb_control_msg (serial->dev,usb_rcvctrlpipe (serial->dev, 0),
 				request, REQTYPE_DEVICE_TO_HOST, 0x0000,
 				0, buf, size, 300);

 	/* Convert data into an array of integers */
 	for (i=0; i<length; i++)
 		data[i] = le32_to_cpu(buf[i]);

 	kfree(buf);

 	if (result != size) {
 		dev_err(&port->dev, "%s - Unable to send config request, "
 				"request=0x%x size=%d result=%d\n",
 				__FUNCTION__, request, size, result);
 		return -EPROTO;
 	}

 	return 0;
 }

 /*
  * cp2101_set_config
  * Writes to the CP2101 configuration registers
  * Values less than 16 bits wide are sent directly
  * 'size' is specified in bytes.
  */
 static int cp2101_set_config(struct usb_serial_port* port, u8 request,
 		unsigned int *data, int size)
 {
 	struct usb_serial *serial = port->serial;
 	__le32 *buf;
 	int result, i, length;

 	/* Number of integers required to contain the array */
 	length = (((size - 1) | 3) + 1)/4;

 	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
 	if (!buf) {
 		dev_err(&port->dev, "%s - out of memory.\n",
 				__FUNCTION__);
 		return -ENOMEM;
 	}

 	/* Array of integers into bytes */
 	for (i = 0; i < length; i++)
 		buf[i] = cpu_to_le32(data[i]);

 	if (size > 2) {
 		result = usb_control_msg (serial->dev,
 				usb_sndctrlpipe(serial->dev, 0),
 				request, REQTYPE_HOST_TO_DEVICE, 0x0000,
 				0, buf, size, 300);
 	} else {
 		result = usb_control_msg (serial->dev,
 				usb_sndctrlpipe(serial->dev, 0),
 				request, REQTYPE_HOST_TO_DEVICE, data[0],
 				0, NULL, 0, 300);
 	}

 	kfree(buf);

 	if ((size > 2 && result != size) || result < 0) {
 		dev_err(&port->dev, "%s - Unable to send request, "
 				"request=0x%x size=%d result=%d\n",
 				__FUNCTION__, request, size, result);
 		return -EPROTO;
 	}

 	/* Single data value */
 	result = usb_control_msg (serial->dev,
 			usb_sndctrlpipe(serial->dev, 0),
 			request, REQTYPE_HOST_TO_DEVICE, data[0],
 			0, NULL, 0, 300);
 	return 0;
 }

 /*
  * cp2101_set_config_single
  * Convenience function for calling cp2101_set_config on single data values
  * without requiring an integer pointer
  */
 static inline int cp2101_set_config_single(struct usb_serial_port* port,
 		u8 request, unsigned int data)
 {
 	return cp2101_set_config(port, request, &data, 2);
 }

 static int cp2101_open (struct usb_serial_port *port, struct file *filp)
 {
 	struct usb_serial *serial = port->serial;
 	int result;

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

 	if (cp2101_set_config_single(port, CP2101_UART, UART_ENABLE)) {
 		dev_err(&port->dev, "%s - Unable to enable UART\n",
 				__FUNCTION__);
 		return -EPROTO;
 	}

 	/* Start reading from the device */
 	usb_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,
 			serial->type->read_bulk_callback,
 			port);
 	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
 	if (result) {
 		dev_err(&port->dev, "%s - failed resubmitting read urb, "
 				"error %d\n", __FUNCTION__, result);
 		return result;
 	}

 	/* Configure the termios structure */
 	cp2101_get_termios(port);

 	/* Set the DTR and RTS pins low */
 	cp2101_tiocmset(port, NULL, TIOCM_DTR | TIOCM_RTS, 0);

 	return 0;
 }

 static void cp2101_cleanup (struct usb_serial_port *port)
 {
 	struct usb_serial *serial = port->serial;

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

 	if (serial->dev) {
 		/* shutdown any bulk reads that might be going on */
 		if (serial->num_bulk_out)
 			usb_kill_urb(port->write_urb);
 		if (serial->num_bulk_in)
 			usb_kill_urb(port->read_urb);
 	}
 }

 static void cp2101_close (struct usb_serial_port *port, struct file * filp)
 {
 	dbg("%s - port %d", __FUNCTION__, port->number);

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

 	mutex_lock(&port->serial->disc_mutex);
 	if (!port->serial->disconnected)
 		cp2101_set_config_single(port, CP2101_UART, UART_DISABLE);
 	mutex_unlock(&port->serial->disc_mutex);
 }

 /*
  * cp2101_get_termios
  * Reads the baud rate, data bits, parity, stop bits and flow control mode
  * from the device, corrects any unsupported values, and configures the
  * termios structure to reflect the state of the device
  */
 static void cp2101_get_termios (struct usb_serial_port *port)
 {
 	unsigned int cflag, modem_ctl[4];
 	int baud;
 	int bits;

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

 	if (!port->tty || !port->tty->termios) {
 		dbg("%s - no tty structures", __FUNCTION__);
 		return;
 	}

 	cp2101_get_config(port, CP2101_BAUDRATE, &baud, 2);
 	/* Convert to baudrate */
 	if (baud)
 		baud = BAUD_RATE_GEN_FREQ / baud;

 	dbg("%s - baud rate = %d", __FUNCTION__, baud);

 	tty_encode_baud_rate(port->tty, baud, baud);
 	cflag = port->tty->termios->c_cflag;

 	cp2101_get_config(port, CP2101_BITS, &bits, 2);
 	cflag &= ~CSIZE;
 	switch(bits & BITS_DATA_MASK) {
 		case BITS_DATA_5:
 			dbg("%s - data bits = 5", __FUNCTION__);
 			cflag |= CS5;
 			break;
 		case BITS_DATA_6:
 			dbg("%s - data bits = 6", __FUNCTION__);
 			cflag |= CS6;
 			break;
 		case BITS_DATA_7:
 			dbg("%s - data bits = 7", __FUNCTION__);
 			cflag |= CS7;
 			break;
 		case BITS_DATA_8:
 			dbg("%s - data bits = 8", __FUNCTION__);
 			cflag |= CS8;
 			break;
 		case BITS_DATA_9:
 			dbg("%s - data bits = 9 (not supported, "
 					"using 8 data bits)", __FUNCTION__);
 			cflag |= CS8;
 			bits &= ~BITS_DATA_MASK;
 			bits |= BITS_DATA_8;
 			cp2101_set_config(port, CP2101_BITS, &bits, 2);
 			break;
 		default:
 			dbg("%s - Unknown number of data bits, "
 					"using 8", __FUNCTION__);
 			cflag |= CS8;
 			bits &= ~BITS_DATA_MASK;
 			bits |= BITS_DATA_8;
 			cp2101_set_config(port, CP2101_BITS, &bits, 2);
 			break;
 	}

 	switch(bits & BITS_PARITY_MASK) {
 		case BITS_PARITY_NONE:
 			dbg("%s - parity = NONE", __FUNCTION__);
 			cflag &= ~PARENB;
 			break;
 		case BITS_PARITY_ODD:
 			dbg("%s - parity = ODD", __FUNCTION__);
 			cflag |= (PARENB|PARODD);
 			break;
 		case BITS_PARITY_EVEN:
 			dbg("%s - parity = EVEN", __FUNCTION__);
 			cflag &= ~PARODD;
 			cflag |= PARENB;
 			break;
 		case BITS_PARITY_MARK:
 			dbg("%s - parity = MARK (not supported, "
 					"disabling parity)", __FUNCTION__);
 			cflag &= ~PARENB;
 			bits &= ~BITS_PARITY_MASK;
 			cp2101_set_config(port, CP2101_BITS, &bits, 2);
 			break;
 		case BITS_PARITY_SPACE:
 			dbg("%s - parity = SPACE (not supported, "
 					"disabling parity)", __FUNCTION__);
 			cflag &= ~PARENB;
 			bits &= ~BITS_PARITY_MASK;
 			cp2101_set_config(port, CP2101_BITS, &bits, 2);
 			break;
 		default:
 			dbg("%s - Unknown parity mode, "
 					"disabling parity", __FUNCTION__);
 			cflag &= ~PARENB;
 			bits &= ~BITS_PARITY_MASK;
 			cp2101_set_config(port, CP2101_BITS, &bits, 2);
 			break;
 	}

 	cflag &= ~CSTOPB;
 	switch(bits & BITS_STOP_MASK) {
 		case BITS_STOP_1:
 			dbg("%s - stop bits = 1", __FUNCTION__);
 			break;
 		case BITS_STOP_1_5:
 			dbg("%s - stop bits = 1.5 (not supported, "
 					"using 1 stop bit)", __FUNCTION__);
 			bits &= ~BITS_STOP_MASK;
 			cp2101_set_config(port, CP2101_BITS, &bits, 2);
 			break;
 		case BITS_STOP_2:
 			dbg("%s - stop bits = 2", __FUNCTION__);
 			cflag |= CSTOPB;
 			break;
 		default:
 			dbg("%s - Unknown number of stop bits, "
 					"using 1 stop bit", __FUNCTION__);
 			bits &= ~BITS_STOP_MASK;
 			cp2101_set_config(port, CP2101_BITS, &bits, 2);
 			break;
 	}

 	cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
 	if (modem_ctl[0] & 0x0008) {
 		dbg("%s - flow control = CRTSCTS", __FUNCTION__);
 		cflag |= CRTSCTS;
 	} else {
 		dbg("%s - flow control = NONE", __FUNCTION__);
 		cflag &= ~CRTSCTS;
 	}

 	port->tty->termios->c_cflag = cflag;
 }

 static void cp2101_set_termios (struct usb_serial_port *port,
 		struct ktermios *old_termios)
 {
 	unsigned int cflag, old_cflag;
 	int baud=0, bits;
 	unsigned int modem_ctl[4];

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

 	if (!port->tty || !port->tty->termios) {
 		dbg("%s - no tty structures", __FUNCTION__);
 		return;
 	}
 	port->tty->termios->c_cflag &= ~CMSPAR;

 	cflag = port->tty->termios->c_cflag;
 	old_cflag = old_termios->c_cflag;
 	baud = tty_get_baud_rate(port->tty);

 	/* If the baud rate is to be updated*/
 	if (baud != tty_termios_baud_rate(old_termios)) {
 		switch (baud) {
 			case 0:
 			case 600:
 			case 1200:
 			case 1800:
 			case 2400:
 			case 4800:
 			case 7200:
 			case 9600:
 			case 14400:
 			case 19200:
 			case 28800:
 			case 38400:
 			case 55854:
 			case 57600:
 			case 115200:
 			case 127117:
 			case 230400:
 			case 460800:
 			case 921600:
 			case 3686400:
 				break;
 			default:
 				baud = 9600;
 				break;
 		}

 		if (baud) {
 			dbg("%s - Setting baud rate to %d baud", __FUNCTION__,
 					baud);
 			if (cp2101_set_config_single(port, CP2101_BAUDRATE,
 						(BAUD_RATE_GEN_FREQ / baud))) {
 				dev_err(&port->dev, "Baud rate requested not "
 						"supported by device\n");
 				baud = tty_termios_baud_rate(old_termios);
 			}
 		}
 	}
 	/* Report back the resulting baud rate */
 	tty_encode_baud_rate(port->tty, baud, baud);

 	/* If the number of data bits is to be updated */
 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
 		cp2101_get_config(port, CP2101_BITS, &bits, 2);
 		bits &= ~BITS_DATA_MASK;
 		switch (cflag & CSIZE) {
 			case CS5:
 				bits |= BITS_DATA_5;
 				dbg("%s - data bits = 5", __FUNCTION__);
 				break;
 			case CS6:
 				bits |= BITS_DATA_6;
 				dbg("%s - data bits = 6", __FUNCTION__);
 				break;
 			case CS7:
 				bits |= BITS_DATA_7;
 				dbg("%s - data bits = 7", __FUNCTION__);
 				break;
 			case CS8:
 				bits |= BITS_DATA_8;
 				dbg("%s - data bits = 8", __FUNCTION__);
 				break;
 			/*case CS9:
 			 	bits |= BITS_DATA_9;
 				dbg("%s - data bits = 9", __FUNCTION__);
 				break;*/
 			default:
 				dev_err(&port->dev, "cp2101 driver does not "
 					"support the number of bits requested,"
 					" using 8 bit mode\n");
 				bits |= BITS_DATA_8;
 				break;
 		}
 		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
 			dev_err(&port->dev, "Number of data bits requested "
 					"not supported by device\n");
 	}

 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))) {
 		cp2101_get_config(port, CP2101_BITS, &bits, 2);
 		bits &= ~BITS_PARITY_MASK;
 		if (cflag & PARENB) {
 			if (cflag & PARODD) {
 				bits |= BITS_PARITY_ODD;
 				dbg("%s - parity = ODD", __FUNCTION__);
 			} else {
 				bits |= BITS_PARITY_EVEN;
 				dbg("%s - parity = EVEN", __FUNCTION__);
 			}
 		}
 		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
 			dev_err(&port->dev, "Parity mode not supported "
 					"by device\n");
 	}

 	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
 		cp2101_get_config(port, CP2101_BITS, &bits, 2);
 		bits &= ~BITS_STOP_MASK;
 		if (cflag & CSTOPB) {
 			bits |= BITS_STOP_2;
 			dbg("%s - stop bits = 2", __FUNCTION__);
 		} else {
 			bits |= BITS_STOP_1;
 			dbg("%s - stop bits = 1", __FUNCTION__);
 		}
 		if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
 			dev_err(&port->dev, "Number of stop bits requested "
 					"not supported by device\n");
 	}

 	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
 		cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
 		dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
 				__FUNCTION__, modem_ctl[0], modem_ctl[1],
 				modem_ctl[2], modem_ctl[3]);

 		if (cflag & CRTSCTS) {
 			modem_ctl[0] &= ~0x7B;
 			modem_ctl[0] |= 0x09;
 			modem_ctl[1] = 0x80;
 			dbg("%s - flow control = CRTSCTS", __FUNCTION__);
 		} else {
 			modem_ctl[0] &= ~0x7B;
 			modem_ctl[0] |= 0x01;
 			modem_ctl[1] |= 0x40;
 			dbg("%s - flow control = NONE", __FUNCTION__);
 		}

 		dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
 				__FUNCTION__, modem_ctl[0], modem_ctl[1],
 				modem_ctl[2], modem_ctl[3]);
 		cp2101_set_config(port, CP2101_MODEMCTL, modem_ctl, 16);
 	}

 }

 static int cp2101_tiocmset (struct usb_serial_port *port, struct file *file,
 		unsigned int set, unsigned int clear)
 {
 	int control = 0;

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

 	if (set & TIOCM_RTS) {
 		control |= CONTROL_RTS;
 		control |= CONTROL_WRITE_RTS;
 	}
 	if (set & TIOCM_DTR) {
 		control |= CONTROL_DTR;
 		control |= CONTROL_WRITE_DTR;
 	}
 	if (clear & TIOCM_RTS) {
 		control &= ~CONTROL_RTS;
 		control |= CONTROL_WRITE_RTS;
 	}
 	if (clear & TIOCM_DTR) {
 		control &= ~CONTROL_DTR;
 		control |= CONTROL_WRITE_DTR;
 	}

 	dbg("%s - control = 0x%.4x", __FUNCTION__, control);

 	return cp2101_set_config(port, CP2101_CONTROL, &control, 2);

 }

 static int cp2101_tiocmget (struct usb_serial_port *port, struct file *file)
 {
 	int control, result;

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

 	cp2101_get_config(port, CP2101_CONTROL, &control, 1);

 	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
 		|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
 		|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
 		|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
 		|((control & CONTROL_RING)? TIOCM_RI  : 0)
 		|((control & CONTROL_DCD) ? TIOCM_CD  : 0);

 	dbg("%s - control = 0x%.2x", __FUNCTION__, control);

 	return result;
 }

 static void cp2101_break_ctl (struct usb_serial_port *port, int break_state)
 {
 	int state;

 	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");
 	cp2101_set_config(port, CP2101_BREAK, &state, 2);
 }

 static int cp2101_startup (struct usb_serial *serial)
 {
 	/* CP2101 buffers behave strangely unless device is reset */
 	usb_reset_device(serial->dev);
 	return 0;
 }

 static void cp2101_shutdown (struct usb_serial *serial)
 {
 	int i;

 	dbg("%s", __FUNCTION__);

 	/* Stop reads and writes on all ports */
 	for (i=0; i < serial->num_ports; ++i) {
 		cp2101_cleanup(serial->port[i]);
 	}
 }

 static int __init cp2101_init (void)
 {
 	int retval;

 	retval = usb_serial_register(&cp2101_device);
 	if (retval)
 		return retval; /* Failed to register */

 	retval = usb_register(&cp2101_driver);
 	if (retval) {
 		/* Failed to register */
 		usb_serial_deregister(&cp2101_device);
 		return retval;
 	}

 	/* Success */
 	info(DRIVER_DESC " " DRIVER_VERSION);
 	return 0;
 }

 static void __exit cp2101_exit (void)
 {
 	usb_deregister (&cp2101_driver);
 	usb_serial_deregister (&cp2101_device);
 }

 module_init(cp2101_init);
 module_exit(cp2101_exit);

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

 module_param(debug, bool, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(debug, "Enable verbose debugging messages");
	/*
	* Silicon Laboratories CP2101/CP2102 USB to RS232 serial adaptor driver
	*
	* Copyright (C) 2005 Craig Shelley (craig@microtron.org.uk)
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License version
	* 2 as published by the Free Software Foundation.
	*
	* Support to set flow control line levels using TIOCMGET and TIOCMSET
	* thanks to Karl Hiramoto karl@hiramoto.org. RTSCTS hardware flow
	* control thanks to Munir Nassar nassarmu@real-time.com
	*
	* Outstanding Issues:
	* Buffers are not flushed when the port is opened.
	* Multiple calls to write() may fail with "Resource temporarily unavailable"
	*
	*/

	#include <linux/kernel.h>
	#include <linux/errno.h>
	#include <linux/slab.h>
	#include <linux/tty.h>
	#include <linux/tty_flip.h>
	#include <linux/module.h>
	#include <linux/moduleparam.h>
	#include <linux/usb.h>
	#include <asm/uaccess.h>
	#include <linux/usb/serial.h>

	/*
	* Version Information
	*/
	#define DRIVER_VERSION "v0.07"
	#define DRIVER_DESC "Silicon Labs CP2101/CP2102 RS232 serial adaptor driver"

	/*
	* Function Prototypes
	*/
	static int cp2101_open(struct usb_serial_port, struct file);
	static void cp2101_cleanup(struct usb_serial_port*);
	static void cp2101_close(struct usb_serial_port, struct file);
	static void cp2101_get_termios(struct usb_serial_port*);
	static void cp2101_set_termios(struct usb_serial_port, struct ktermios);
	static int cp2101_tiocmget (struct usb_serial_port , struct file );
	static int cp2101_tiocmset (struct usb_serial_port , struct file ,
	unsigned int, unsigned int);
	static void cp2101_break_ctl(struct usb_serial_port*, int);
	static int cp2101_startup (struct usb_serial *);
	static void cp2101_shutdown(struct usb_serial*);


	static int debug;

	static struct usb_device_id id_table [] = {
	{ USB_DEVICE(0x08e6, 0x5501) }, /* Gemalto Prox-PU/CU contactless smartcard reader */
	{ USB_DEVICE(0x0FCF, 0x1003) }, /* Dynastream ANT development board */
	{ USB_DEVICE(0x0FCF, 0x1004) }, /* Dynastream ANT2USB */
	{ USB_DEVICE(0x10A6, 0xAA26) }, /* Knock-off DCU-11 cable */
	{ USB_DEVICE(0x10AB, 0x10C5) }, /* Siemens MC60 Cable */
	{ USB_DEVICE(0x10B5, 0xAC70) }, /* Nokia CA-42 USB */
	{ USB_DEVICE(0x10C4, 0x800A) }, /* SPORTident BSM7-D-USB main station */
	{ USB_DEVICE(0x10C4, 0x803B) }, /* Pololu USB-serial converter */
	{ USB_DEVICE(0x10C4, 0x8053) }, /* Enfora EDG1228 */
	{ USB_DEVICE(0x10C4, 0x8066) }, /* Argussoft In-System Programmer */
	{ USB_DEVICE(0x10C4, 0x807A) }, /* Crumb128 board */
	{ USB_DEVICE(0x10C4, 0x80CA) }, /* Degree Controls Inc */
	{ USB_DEVICE(0x10C4, 0x80DD) }, /* Tracient RFID */
	{ USB_DEVICE(0x10C4, 0x80F6) }, /* Suunto sports instrument */
	{ USB_DEVICE(0x10C4, 0x813D) }, /* Burnside Telecom Deskmobile */
	{ USB_DEVICE(0x10C4, 0x814A) }, /* West Mountain Radio RIGblaster P&P */
	{ USB_DEVICE(0x10C4, 0x814B) }, /* West Mountain Radio RIGtalk */
	{ USB_DEVICE(0x10C4, 0x815E) }, /* Helicomm IP-Link 1220-DVM */
	{ USB_DEVICE(0x10C4, 0x81C8) }, /* Lipowsky Industrie Elektronik GmbH, Baby-JTAG */
	{ USB_DEVICE(0x10C4, 0x81E2) }, /* Lipowsky Industrie Elektronik GmbH, Baby-LIN */
	{ USB_DEVICE(0x10C4, 0x81E7) }, /* Aerocomm Radio */
	{ USB_DEVICE(0x10C4, 0x8218) }, /* Lipowsky Industrie Elektronik GmbH, HARP-1 */
	{ USB_DEVICE(0x10c4, 0x8293) }, /* Telegesys ETRX2USB */
	{ USB_DEVICE(0x10C4, 0xEA60) }, /* Silicon Labs factory default */
	{ USB_DEVICE(0x10C4, 0xEA61) }, /* Silicon Labs factory default */
	{ USB_DEVICE(0x10C4, 0xF001) }, /* Elan Digital Systems USBscope50 */
	{ USB_DEVICE(0x10C4, 0xF002) }, /* Elan Digital Systems USBwave12 */
	{ USB_DEVICE(0x10C4, 0xF003) }, /* Elan Digital Systems USBpulse100 */
	{ USB_DEVICE(0x10C4, 0xF004) }, /* Elan Digital Systems USBcount50 */
	{ USB_DEVICE(0x10C5, 0xEA61) }, /* Silicon Labs MobiData GPRS USB Modem */
	{ USB_DEVICE(0x13AD, 0x9999) }, /* Baltech card reader */
	{ USB_DEVICE(0x166A, 0x0303) }, /* Clipsal 5500PCU C-Bus USB interface */
	{ USB_DEVICE(0x16D6, 0x0001) }, /* Jablotron serial interface */
	{ } /* Terminating Entry */
	};

	MODULE_DEVICE_TABLE (usb, id_table);

	static struct usb_driver cp2101_driver = {
	.name = "cp2101",
	.probe = usb_serial_probe,
	.disconnect = usb_serial_disconnect,
	.id_table = id_table,
	.no_dynamic_id = 1,
	};

	static struct usb_serial_driver cp2101_device = {
	.driver = {
	.owner = THIS_MODULE,
	.name = "cp2101",
	},
	.usb_driver = &cp2101_driver,
	.id_table = id_table,
	.num_interrupt_in = 0,
	.num_bulk_in = NUM_DONT_CARE,
	.num_bulk_out = NUM_DONT_CARE,
	.num_ports = 1,
	.open = cp2101_open,
	.close = cp2101_close,
	.break_ctl = cp2101_break_ctl,
	.set_termios = cp2101_set_termios,
	.tiocmget = cp2101_tiocmget,
	.tiocmset = cp2101_tiocmset,
	.attach = cp2101_startup,
	.shutdown = cp2101_shutdown,
	};

	/* Config request types */
	#define REQTYPE_HOST_TO_DEVICE 0x41
	#define REQTYPE_DEVICE_TO_HOST 0xc1

	/* Config SET requests. To GET, add 1 to the request number */
	#define CP2101_UART 0x00 /* Enable / Disable */
	#define CP2101_BAUDRATE 0x01 /* (BAUD_RATE_GEN_FREQ / baudrate) */
	#define CP2101_BITS 0x03 /* 0x(0)(databits)(parity)(stopbits) */
	#define CP2101_BREAK 0x05 /* On / Off */
	#define CP2101_CONTROL 0x07 /* Flow control line states */
	#define CP2101_MODEMCTL 0x13 /* Modem controls */
	#define CP2101_CONFIG_6 0x19 /* 6 bytes of config data ??? */

	/* CP2101_UART */
	#define UART_ENABLE 0x0001
	#define UART_DISABLE 0x0000

	/* CP2101_BAUDRATE */
	#define BAUD_RATE_GEN_FREQ 0x384000

	/* CP2101_BITS */
	#define BITS_DATA_MASK 0X0f00
	#define BITS_DATA_5 0X0500
	#define BITS_DATA_6 0X0600
	#define BITS_DATA_7 0X0700
	#define BITS_DATA_8 0X0800
	#define BITS_DATA_9 0X0900

	#define BITS_PARITY_MASK 0x00f0
	#define BITS_PARITY_NONE 0x0000
	#define BITS_PARITY_ODD 0x0010
	#define BITS_PARITY_EVEN 0x0020
	#define BITS_PARITY_MARK 0x0030
	#define BITS_PARITY_SPACE 0x0040

	#define BITS_STOP_MASK 0x000f
	#define BITS_STOP_1 0x0000
	#define BITS_STOP_1_5 0x0001
	#define BITS_STOP_2 0x0002

	/* CP2101_BREAK */
	#define BREAK_ON 0x0000
	#define BREAK_OFF 0x0001

	/* CP2101_CONTROL */
	#define CONTROL_DTR 0x0001
	#define CONTROL_RTS 0x0002
	#define CONTROL_CTS 0x0010
	#define CONTROL_DSR 0x0020
	#define CONTROL_RING 0x0040
	#define CONTROL_DCD 0x0080
	#define CONTROL_WRITE_DTR 0x0100
	#define CONTROL_WRITE_RTS 0x0200

	/*
	* cp2101_get_config
	* Reads from the CP2101 configuration registers
	* 'size' is specified in bytes.
	* 'data' is a pointer to a pre-allocated array of integers large
	* enough to hold 'size' bytes (with 4 bytes to each integer)
	*/
	static int cp2101_get_config(struct usb_serial_port* port, u8 request,
	unsigned int *data, int size)
	{
	struct usb_serial *serial = port->serial;
	__le32 *buf;
	int result, i, length;

	/* Number of integers required to contain the array */
	length = (((size - 1) \| 3) + 1)/4;

	buf = kcalloc(length, sizeof(__le32), GFP_KERNEL);
	if (!buf) {
	dev_err(&port->dev, "%s - out of memory.\n", __FUNCTION__);
	return -ENOMEM;
	}

	/* For get requests, the request number must be incremented */
	request++;

	/* Issue the request, attempting to read 'size' bytes */
	result = usb_control_msg (serial->dev,usb_rcvctrlpipe (serial->dev, 0),
	request, REQTYPE_DEVICE_TO_HOST, 0x0000,
	0, buf, size, 300);

	/* Convert data into an array of integers */
	for (i=0; i<length; i++)
	data[i] = le32_to_cpu(buf[i]);

	kfree(buf);

	if (result != size) {
	dev_err(&port->dev, "%s - Unable to send config request, "
	"request=0x%x size=%d result=%d\n",
	__FUNCTION__, request, size, result);
	return -EPROTO;
	}

	return 0;
	}

	/*
	* cp2101_set_config
	* Writes to the CP2101 configuration registers
	* Values less than 16 bits wide are sent directly
	* 'size' is specified in bytes.
	*/
	static int cp2101_set_config(struct usb_serial_port* port, u8 request,
	unsigned int *data, int size)
	{
	struct usb_serial *serial = port->serial;
	__le32 *buf;
	int result, i, length;

	/* Number of integers required to contain the array */
	length = (((size - 1) \| 3) + 1)/4;

	buf = kmalloc(length * sizeof(__le32), GFP_KERNEL);
	if (!buf) {
	dev_err(&port->dev, "%s - out of memory.\n",
	__FUNCTION__);
	return -ENOMEM;
	}

	/* Array of integers into bytes */
	for (i = 0; i < length; i++)
	buf[i] = cpu_to_le32(data[i]);

	if (size > 2) {
	result = usb_control_msg (serial->dev,
	usb_sndctrlpipe(serial->dev, 0),
	request, REQTYPE_HOST_TO_DEVICE, 0x0000,
	0, buf, size, 300);
	} else {
	result = usb_control_msg (serial->dev,
	usb_sndctrlpipe(serial->dev, 0),
	request, REQTYPE_HOST_TO_DEVICE, data[0],
	0, NULL, 0, 300);
	}

	kfree(buf);

	if ((size > 2 && result != size) \|\| result < 0) {
	dev_err(&port->dev, "%s - Unable to send request, "
	"request=0x%x size=%d result=%d\n",
	__FUNCTION__, request, size, result);
	return -EPROTO;
	}

	/* Single data value */
	result = usb_control_msg (serial->dev,
	usb_sndctrlpipe(serial->dev, 0),
	request, REQTYPE_HOST_TO_DEVICE, data[0],
	0, NULL, 0, 300);
	return 0;
	}

	/*
	* cp2101_set_config_single
	* Convenience function for calling cp2101_set_config on single data values
	* without requiring an integer pointer
	*/
	static inline int cp2101_set_config_single(struct usb_serial_port* port,
	u8 request, unsigned int data)
	{
	return cp2101_set_config(port, request, &data, 2);
	}

	static int cp2101_open (struct usb_serial_port port, struct file filp)
	{
	struct usb_serial *serial = port->serial;
	int result;

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

	if (cp2101_set_config_single(port, CP2101_UART, UART_ENABLE)) {
	dev_err(&port->dev, "%s - Unable to enable UART\n",
	__FUNCTION__);
	return -EPROTO;
	}

	/* Start reading from the device */
	usb_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,
	serial->type->read_bulk_callback,
	port);
	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
	if (result) {
	dev_err(&port->dev, "%s - failed resubmitting read urb, "
	"error %d\n", __FUNCTION__, result);
	return result;
	}

	/* Configure the termios structure */
	cp2101_get_termios(port);

	/* Set the DTR and RTS pins low */
	cp2101_tiocmset(port, NULL, TIOCM_DTR \| TIOCM_RTS, 0);

	return 0;
	}

	static void cp2101_cleanup (struct usb_serial_port *port)
	{
	struct usb_serial *serial = port->serial;

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

	if (serial->dev) {
	/* shutdown any bulk reads that might be going on */
	if (serial->num_bulk_out)
	usb_kill_urb(port->write_urb);
	if (serial->num_bulk_in)
	usb_kill_urb(port->read_urb);
	}
	}

	static void cp2101_close (struct usb_serial_port port, struct file filp)
	{
	dbg("%s - port %d", __FUNCTION__, port->number);

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

	mutex_lock(&port->serial->disc_mutex);
	if (!port->serial->disconnected)
	cp2101_set_config_single(port, CP2101_UART, UART_DISABLE);
	mutex_unlock(&port->serial->disc_mutex);
	}

	/*
	* cp2101_get_termios
	* Reads the baud rate, data bits, parity, stop bits and flow control mode
	* from the device, corrects any unsupported values, and configures the
	* termios structure to reflect the state of the device
	*/
	static void cp2101_get_termios (struct usb_serial_port *port)
	{
	unsigned int cflag, modem_ctl[4];
	int baud;
	int bits;

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

	if (!port->tty \|\| !port->tty->termios) {
	dbg("%s - no tty structures", __FUNCTION__);
	return;
	}

	cp2101_get_config(port, CP2101_BAUDRATE, &baud, 2);
	/* Convert to baudrate */
	if (baud)
	baud = BAUD_RATE_GEN_FREQ / baud;

	dbg("%s - baud rate = %d", __FUNCTION__, baud);

	tty_encode_baud_rate(port->tty, baud, baud);
	cflag = port->tty->termios->c_cflag;

	cp2101_get_config(port, CP2101_BITS, &bits, 2);
	cflag &= ~CSIZE;
	switch(bits & BITS_DATA_MASK) {
	case BITS_DATA_5:
	dbg("%s - data bits = 5", __FUNCTION__);
	cflag \|= CS5;
	break;
	case BITS_DATA_6:
	dbg("%s - data bits = 6", __FUNCTION__);
	cflag \|= CS6;
	break;
	case BITS_DATA_7:
	dbg("%s - data bits = 7", __FUNCTION__);
	cflag \|= CS7;
	break;
	case BITS_DATA_8:
	dbg("%s - data bits = 8", __FUNCTION__);
	cflag \|= CS8;
	break;
	case BITS_DATA_9:
	dbg("%s - data bits = 9 (not supported, "
	"using 8 data bits)", __FUNCTION__);
	cflag \|= CS8;
	bits &= ~BITS_DATA_MASK;
	bits \|= BITS_DATA_8;
	cp2101_set_config(port, CP2101_BITS, &bits, 2);
	break;
	default:
	dbg("%s - Unknown number of data bits, "
	"using 8", __FUNCTION__);
	cflag \|= CS8;
	bits &= ~BITS_DATA_MASK;
	bits \|= BITS_DATA_8;
	cp2101_set_config(port, CP2101_BITS, &bits, 2);
	break;
	}

	switch(bits & BITS_PARITY_MASK) {
	case BITS_PARITY_NONE:
	dbg("%s - parity = NONE", __FUNCTION__);
	cflag &= ~PARENB;
	break;
	case BITS_PARITY_ODD:
	dbg("%s - parity = ODD", __FUNCTION__);
	cflag \|= (PARENB\|PARODD);
	break;
	case BITS_PARITY_EVEN:
	dbg("%s - parity = EVEN", __FUNCTION__);
	cflag &= ~PARODD;
	cflag \|= PARENB;
	break;
	case BITS_PARITY_MARK:
	dbg("%s - parity = MARK (not supported, "
	"disabling parity)", __FUNCTION__);
	cflag &= ~PARENB;
	bits &= ~BITS_PARITY_MASK;
	cp2101_set_config(port, CP2101_BITS, &bits, 2);
	break;
	case BITS_PARITY_SPACE:
	dbg("%s - parity = SPACE (not supported, "
	"disabling parity)", __FUNCTION__);
	cflag &= ~PARENB;
	bits &= ~BITS_PARITY_MASK;
	cp2101_set_config(port, CP2101_BITS, &bits, 2);
	break;
	default:
	dbg("%s - Unknown parity mode, "
	"disabling parity", __FUNCTION__);
	cflag &= ~PARENB;
	bits &= ~BITS_PARITY_MASK;
	cp2101_set_config(port, CP2101_BITS, &bits, 2);
	break;
	}

	cflag &= ~CSTOPB;
	switch(bits & BITS_STOP_MASK) {
	case BITS_STOP_1:
	dbg("%s - stop bits = 1", __FUNCTION__);
	break;
	case BITS_STOP_1_5:
	dbg("%s - stop bits = 1.5 (not supported, "
	"using 1 stop bit)", __FUNCTION__);
	bits &= ~BITS_STOP_MASK;
	cp2101_set_config(port, CP2101_BITS, &bits, 2);
	break;
	case BITS_STOP_2:
	dbg("%s - stop bits = 2", __FUNCTION__);
	cflag \|= CSTOPB;
	break;
	default:
	dbg("%s - Unknown number of stop bits, "
	"using 1 stop bit", __FUNCTION__);
	bits &= ~BITS_STOP_MASK;
	cp2101_set_config(port, CP2101_BITS, &bits, 2);
	break;
	}

	cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
	if (modem_ctl[0] & 0x0008) {
	dbg("%s - flow control = CRTSCTS", __FUNCTION__);
	cflag \|= CRTSCTS;
	} else {
	dbg("%s - flow control = NONE", __FUNCTION__);
	cflag &= ~CRTSCTS;
	}

	port->tty->termios->c_cflag = cflag;
	}

	static void cp2101_set_termios (struct usb_serial_port *port,
	struct ktermios *old_termios)
	{
	unsigned int cflag, old_cflag;
	int baud=0, bits;
	unsigned int modem_ctl[4];

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

	if (!port->tty \|\| !port->tty->termios) {
	dbg("%s - no tty structures", __FUNCTION__);
	return;
	}
	port->tty->termios->c_cflag &= ~CMSPAR;

	cflag = port->tty->termios->c_cflag;
	old_cflag = old_termios->c_cflag;
	baud = tty_get_baud_rate(port->tty);

	/* If the baud rate is to be updated*/
	if (baud != tty_termios_baud_rate(old_termios)) {
	switch (baud) {
	case 0:
	case 600:
	case 1200:
	case 1800:
	case 2400:
	case 4800:
	case 7200:
	case 9600:
	case 14400:
	case 19200:
	case 28800:
	case 38400:
	case 55854:
	case 57600:
	case 115200:
	case 127117:
	case 230400:
	case 460800:
	case 921600:
	case 3686400:
	break;
	default:
	baud = 9600;
	break;
	}

	if (baud) {
	dbg("%s - Setting baud rate to %d baud", __FUNCTION__,
	baud);
	if (cp2101_set_config_single(port, CP2101_BAUDRATE,
	(BAUD_RATE_GEN_FREQ / baud))) {
	dev_err(&port->dev, "Baud rate requested not "
	"supported by device\n");
	baud = tty_termios_baud_rate(old_termios);
	}
	}
	}
	/* Report back the resulting baud rate */
	tty_encode_baud_rate(port->tty, baud, baud);

	/* If the number of data bits is to be updated */
	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
	cp2101_get_config(port, CP2101_BITS, &bits, 2);
	bits &= ~BITS_DATA_MASK;
	switch (cflag & CSIZE) {
	case CS5:
	bits \|= BITS_DATA_5;
	dbg("%s - data bits = 5", __FUNCTION__);
	break;
	case CS6:
	bits \|= BITS_DATA_6;
	dbg("%s - data bits = 6", __FUNCTION__);
	break;
	case CS7:
	bits \|= BITS_DATA_7;
	dbg("%s - data bits = 7", __FUNCTION__);
	break;
	case CS8:
	bits \|= BITS_DATA_8;
	dbg("%s - data bits = 8", __FUNCTION__);
	break;
	/*case CS9:
	bits \|= BITS_DATA_9;
	dbg("%s - data bits = 9", __FUNCTION__);
	break;*/
	default:
	dev_err(&port->dev, "cp2101 driver does not "
	"support the number of bits requested,"
	" using 8 bit mode\n");
	bits \|= BITS_DATA_8;
	break;
	}
	if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
	dev_err(&port->dev, "Number of data bits requested "
	"not supported by device\n");
	}

	if ((cflag & (PARENB\|PARODD)) != (old_cflag & (PARENB\|PARODD))) {
	cp2101_get_config(port, CP2101_BITS, &bits, 2);
	bits &= ~BITS_PARITY_MASK;
	if (cflag & PARENB) {
	if (cflag & PARODD) {
	bits \|= BITS_PARITY_ODD;
	dbg("%s - parity = ODD", __FUNCTION__);
	} else {
	bits \|= BITS_PARITY_EVEN;
	dbg("%s - parity = EVEN", __FUNCTION__);
	}
	}
	if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
	dev_err(&port->dev, "Parity mode not supported "
	"by device\n");
	}

	if ((cflag & CSTOPB) != (old_cflag & CSTOPB)) {
	cp2101_get_config(port, CP2101_BITS, &bits, 2);
	bits &= ~BITS_STOP_MASK;
	if (cflag & CSTOPB) {
	bits \|= BITS_STOP_2;
	dbg("%s - stop bits = 2", __FUNCTION__);
	} else {
	bits \|= BITS_STOP_1;
	dbg("%s - stop bits = 1", __FUNCTION__);
	}
	if (cp2101_set_config(port, CP2101_BITS, &bits, 2))
	dev_err(&port->dev, "Number of stop bits requested "
	"not supported by device\n");
	}

	if ((cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
	cp2101_get_config(port, CP2101_MODEMCTL, modem_ctl, 16);
	dbg("%s - read modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
	__FUNCTION__, modem_ctl[0], modem_ctl[1],
	modem_ctl[2], modem_ctl[3]);

	if (cflag & CRTSCTS) {
	modem_ctl[0] &= ~0x7B;
	modem_ctl[0] \|= 0x09;
	modem_ctl[1] = 0x80;
	dbg("%s - flow control = CRTSCTS", __FUNCTION__);
	} else {
	modem_ctl[0] &= ~0x7B;
	modem_ctl[0] \|= 0x01;
	modem_ctl[1] \|= 0x40;
	dbg("%s - flow control = NONE", __FUNCTION__);
	}

	dbg("%s - write modem controls = 0x%.4x 0x%.4x 0x%.4x 0x%.4x",
	__FUNCTION__, modem_ctl[0], modem_ctl[1],
	modem_ctl[2], modem_ctl[3]);
	cp2101_set_config(port, CP2101_MODEMCTL, modem_ctl, 16);
	}

	}

	static int cp2101_tiocmset (struct usb_serial_port port, struct file file,
	unsigned int set, unsigned int clear)
	{
	int control = 0;

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

	if (set & TIOCM_RTS) {
	control \|= CONTROL_RTS;
	control \|= CONTROL_WRITE_RTS;
	}
	if (set & TIOCM_DTR) {
	control \|= CONTROL_DTR;
	control \|= CONTROL_WRITE_DTR;
	}
	if (clear & TIOCM_RTS) {
	control &= ~CONTROL_RTS;
	control \|= CONTROL_WRITE_RTS;
	}
	if (clear & TIOCM_DTR) {
	control &= ~CONTROL_DTR;
	control \|= CONTROL_WRITE_DTR;
	}

	dbg("%s - control = 0x%.4x", __FUNCTION__, control);

	return cp2101_set_config(port, CP2101_CONTROL, &control, 2);

	}

	static int cp2101_tiocmget (struct usb_serial_port port, struct file file)
	{
	int control, result;

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

	cp2101_get_config(port, CP2101_CONTROL, &control, 1);

	result = ((control & CONTROL_DTR) ? TIOCM_DTR : 0)
	\|((control & CONTROL_RTS) ? TIOCM_RTS : 0)
	\|((control & CONTROL_CTS) ? TIOCM_CTS : 0)
	\|((control & CONTROL_DSR) ? TIOCM_DSR : 0)
	\|((control & CONTROL_RING)? TIOCM_RI : 0)
	\|((control & CONTROL_DCD) ? TIOCM_CD : 0);

	dbg("%s - control = 0x%.2x", __FUNCTION__, control);

	return result;
	}

	static void cp2101_break_ctl (struct usb_serial_port *port, int break_state)
	{
	int state;

	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");
	cp2101_set_config(port, CP2101_BREAK, &state, 2);
	}

	static int cp2101_startup (struct usb_serial *serial)
	{
	/* CP2101 buffers behave strangely unless device is reset */
	usb_reset_device(serial->dev);
	return 0;
	}

	static void cp2101_shutdown (struct usb_serial *serial)
	{
	int i;

	dbg("%s", __FUNCTION__);

	/* Stop reads and writes on all ports */
	for (i=0; i < serial->num_ports; ++i) {
	cp2101_cleanup(serial->port[i]);
	}
	}

	static int __init cp2101_init (void)
	{
	int retval;

	retval = usb_serial_register(&cp2101_device);
	if (retval)
	return retval; /* Failed to register */

	retval = usb_register(&cp2101_driver);
	if (retval) {
	/* Failed to register */
	usb_serial_deregister(&cp2101_device);
	return retval;
	}

	/* Success */
	info(DRIVER_DESC " " DRIVER_VERSION);
	return 0;
	}

	static void __exit cp2101_exit (void)
	{
	usb_deregister (&cp2101_driver);
	usb_serial_deregister (&cp2101_device);
	}

	module_init(cp2101_init);
	module_exit(cp2101_exit);

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

	module_param(debug, bool, S_IRUGO \| S_IWUSR);
	MODULE_PARM_DESC(debug, "Enable verbose debugging messages");