drivers/usb/serial/ssu100.c - third_party/linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 /*
  * usb-serial driver for Quatech SSU-100
  *
  * based on ftdi_sio.c and the original serqt_usb.c from Quatech
  *
  */

 #include <linux/errno.h>
 #include <linux/slab.h>
 #include <linux/tty.h>
 #include <linux/tty_driver.h>
 #include <linux/tty_flip.h>
 #include <linux/module.h>
 #include <linux/serial.h>
 #include <linux/usb.h>
 #include <linux/usb/serial.h>
 #include <linux/serial_reg.h>
 #include <linux/uaccess.h>

 #define QT_OPEN_CLOSE_CHANNEL       0xca
 #define QT_SET_GET_DEVICE           0xc2
 #define QT_SET_GET_REGISTER         0xc0
 #define QT_GET_SET_PREBUF_TRIG_LVL  0xcc
 #define QT_SET_ATF                  0xcd
 #define QT_GET_SET_UART             0xc1
 #define QT_TRANSFER_IN              0xc0
 #define QT_HW_FLOW_CONTROL_MASK     0xc5
 #define QT_SW_FLOW_CONTROL_MASK     0xc6

 #define  SERIAL_MSR_MASK            0xf0

 #define  SERIAL_CRTSCTS ((UART_MCR_RTS << 8) | UART_MSR_CTS)

 #define  SERIAL_EVEN_PARITY         (UART_LCR_PARITY | UART_LCR_EPAR)

 #define  MAX_BAUD_RATE              460800

 #define ATC_DISABLED                0x00
 #define DUPMODE_BITS        0xc0
 #define RR_BITS             0x03
 #define LOOPMODE_BITS       0x41
 #define RS232_MODE          0x00
 #define RTSCTS_TO_CONNECTOR 0x40
 #define CLKS_X4             0x02
 #define FULLPWRBIT          0x00000080
 #define NEXT_BOARD_POWER_BIT        0x00000004

 #define DRIVER_DESC "Quatech SSU-100 USB to Serial Driver"

 #define	USB_VENDOR_ID_QUATECH	0x061d	/* Quatech VID */
 #define QUATECH_SSU100	0xC020	/* SSU100 */

 static const struct usb_device_id id_table[] = {
 	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU100)},
 	{}			/* Terminating entry */
 };
 MODULE_DEVICE_TABLE(usb, id_table);

 struct ssu100_port_private {
 	spinlock_t status_lock;
 	u8 shadowLSR;
 	u8 shadowMSR;
 };

 static inline int ssu100_control_msg(struct usb_device *dev,
 				     u8 request, u16 data, u16 index)
 {
 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 			       request, 0x40, data, index,
 			       NULL, 0, 300);
 }

 static inline int ssu100_setdevice(struct usb_device *dev, u8 *data)
 {
 	u16 x = ((u16)(data[1] << 8) | (u16)(data[0]));

 	return ssu100_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
 }


 static inline int ssu100_getdevice(struct usb_device *dev, u8 *data)
 {
 	int ret;

 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 			      QT_SET_GET_DEVICE, 0xc0, 0, 0,
 			      data, 3, 300);
 	if (ret < 3) {
 		if (ret >= 0)
 			ret = -EIO;
 	}

 	return ret;
 }

 static inline int ssu100_getregister(struct usb_device *dev,
 				     unsigned short uart,
 				     unsigned short reg,
 				     u8 *data)
 {
 	int ret;

 	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 			      QT_SET_GET_REGISTER, 0xc0, reg,
 			      uart, data, sizeof(*data), 300);
 	if (ret < sizeof(*data)) {
 		if (ret >= 0)
 			ret = -EIO;
 	}

 	return ret;
 }


 static inline int ssu100_setregister(struct usb_device *dev,
 				     unsigned short uart,
 				     unsigned short reg,
 				     u16 data)
 {
 	u16 value = (data << 8) | reg;

 	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
 			       QT_SET_GET_REGISTER, 0x40, value, uart,
 			       NULL, 0, 300);

 }

 #define set_mctrl(dev, set)		update_mctrl((dev), (set), 0)
 #define clear_mctrl(dev, clear)	update_mctrl((dev), 0, (clear))

 /* these do not deal with device that have more than 1 port */
 static inline int update_mctrl(struct usb_device *dev, unsigned int set,
 			       unsigned int clear)
 {
 	unsigned urb_value;
 	int result;

 	if (((set | clear) & (TIOCM_DTR | TIOCM_RTS)) == 0) {
 		dev_dbg(&dev->dev, "%s - DTR|RTS not being set|cleared\n", __func__);
 		return 0;	/* no change */
 	}

 	clear &= ~set;	/* 'set' takes precedence over 'clear' */
 	urb_value = 0;
 	if (set & TIOCM_DTR)
 		urb_value |= UART_MCR_DTR;
 	if (set & TIOCM_RTS)
 		urb_value |= UART_MCR_RTS;

 	result = ssu100_setregister(dev, 0, UART_MCR, urb_value);
 	if (result < 0)
 		dev_dbg(&dev->dev, "%s Error from MODEM_CTRL urb\n", __func__);

 	return result;
 }

 static int ssu100_initdevice(struct usb_device *dev)
 {
 	u8 *data;
 	int result = 0;

 	data = kzalloc(3, GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;

 	result = ssu100_getdevice(dev, data);
 	if (result < 0) {
 		dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
 		goto out;
 	}

 	data[1] &= ~FULLPWRBIT;

 	result = ssu100_setdevice(dev, data);
 	if (result < 0) {
 		dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
 		goto out;
 	}

 	result = ssu100_control_msg(dev, QT_GET_SET_PREBUF_TRIG_LVL, 128, 0);
 	if (result < 0) {
 		dev_dbg(&dev->dev, "%s - set prebuffer level failed %i\n", __func__, result);
 		goto out;
 	}

 	result = ssu100_control_msg(dev, QT_SET_ATF, ATC_DISABLED, 0);
 	if (result < 0) {
 		dev_dbg(&dev->dev, "%s - set ATFprebuffer level failed %i\n", __func__, result);
 		goto out;
 	}

 	result = ssu100_getdevice(dev, data);
 	if (result < 0) {
 		dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
 		goto out;
 	}

 	data[0] &= ~(RR_BITS | DUPMODE_BITS);
 	data[0] |= CLKS_X4;
 	data[1] &= ~(LOOPMODE_BITS);
 	data[1] |= RS232_MODE;

 	result = ssu100_setdevice(dev, data);
 	if (result < 0) {
 		dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
 		goto out;
 	}

 out:	kfree(data);
 	return result;

 }


 static void ssu100_set_termios(struct tty_struct *tty,
 			       struct usb_serial_port *port,
 			       struct ktermios *old_termios)
 {
 	struct usb_device *dev = port->serial->dev;
 	struct ktermios *termios = &tty->termios;
 	u16 baud, divisor, remainder;
 	unsigned int cflag = termios->c_cflag;
 	u16 urb_value = 0; /* will hold the new flags */
 	int result;

 	if (cflag & PARENB) {
 		if (cflag & PARODD)
 			urb_value |= UART_LCR_PARITY;
 		else
 			urb_value |= SERIAL_EVEN_PARITY;
 	}

 	switch (cflag & CSIZE) {
 	case CS5:
 		urb_value |= UART_LCR_WLEN5;
 		break;
 	case CS6:
 		urb_value |= UART_LCR_WLEN6;
 		break;
 	case CS7:
 		urb_value |= UART_LCR_WLEN7;
 		break;
 	default:
 	case CS8:
 		urb_value |= UART_LCR_WLEN8;
 		break;
 	}

 	baud = tty_get_baud_rate(tty);
 	if (!baud)
 		baud = 9600;

 	dev_dbg(&port->dev, "%s - got baud = %d\n", __func__, baud);


 	divisor = MAX_BAUD_RATE / baud;
 	remainder = MAX_BAUD_RATE % baud;
 	if (((remainder * 2) >= baud) && (baud != 110))
 		divisor++;

 	urb_value = urb_value << 8;

 	result = ssu100_control_msg(dev, QT_GET_SET_UART, divisor, urb_value);
 	if (result < 0)
 		dev_dbg(&port->dev, "%s - set uart failed\n", __func__);

 	if (cflag & CRTSCTS)
 		result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
 					    SERIAL_CRTSCTS, 0);
 	else
 		result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
 					    0, 0);
 	if (result < 0)
 		dev_dbg(&port->dev, "%s - set HW flow control failed\n", __func__);

 	if (I_IXOFF(tty) || I_IXON(tty)) {
 		u16 x = ((u16)(START_CHAR(tty) << 8) | (u16)(STOP_CHAR(tty)));

 		result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
 					    x, 0);
 	} else
 		result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
 					    0, 0);

 	if (result < 0)
 		dev_dbg(&port->dev, "%s - set SW flow control failed\n", __func__);

 }


 static int ssu100_open(struct tty_struct *tty, struct usb_serial_port *port)
 {
 	struct usb_device *dev = port->serial->dev;
 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
 	u8 *data;
 	int result;
 	unsigned long flags;

 	data = kzalloc(2, GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;

 	result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
 				 QT_OPEN_CLOSE_CHANNEL,
 				 QT_TRANSFER_IN, 0x01,
 				 0, data, 2, 300);
 	if (result < 2) {
 		dev_dbg(&port->dev, "%s - open failed %i\n", __func__, result);
 		if (result >= 0)
 			result = -EIO;
 		kfree(data);
 		return result;
 	}

 	spin_lock_irqsave(&priv->status_lock, flags);
 	priv->shadowLSR = data[0];
 	priv->shadowMSR = data[1];
 	spin_unlock_irqrestore(&priv->status_lock, flags);

 	kfree(data);

 /* set to 9600 */
 	result = ssu100_control_msg(dev, QT_GET_SET_UART, 0x30, 0x0300);
 	if (result < 0)
 		dev_dbg(&port->dev, "%s - set uart failed\n", __func__);

 	if (tty)
 		ssu100_set_termios(tty, port, &tty->termios);

 	return usb_serial_generic_open(tty, port);
 }

 static int get_serial_info(struct usb_serial_port *port,
 			   struct serial_struct __user *retinfo)
 {
 	struct serial_struct tmp;

 	memset(&tmp, 0, sizeof(tmp));
 	tmp.line		= port->minor;
 	tmp.port		= 0;
 	tmp.irq			= 0;
 	tmp.xmit_fifo_size	= port->bulk_out_size;
 	tmp.baud_base		= 9600;
 	tmp.close_delay		= 5*HZ;
 	tmp.closing_wait	= 30*HZ;

 	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
 		return -EFAULT;
 	return 0;
 }

 static int ssu100_ioctl(struct tty_struct *tty,
 		    unsigned int cmd, unsigned long arg)
 {
 	struct usb_serial_port *port = tty->driver_data;

 	switch (cmd) {
 	case TIOCGSERIAL:
 		return get_serial_info(port,
 				       (struct serial_struct __user *) arg);
 	default:
 		break;
 	}

 	return -ENOIOCTLCMD;
 }

 static int ssu100_attach(struct usb_serial *serial)
 {
 	return ssu100_initdevice(serial->dev);
 }

 static int ssu100_port_probe(struct usb_serial_port *port)
 {
 	struct ssu100_port_private *priv;

 	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;

 	spin_lock_init(&priv->status_lock);

 	usb_set_serial_port_data(port, priv);

 	return 0;
 }

 static int ssu100_port_remove(struct usb_serial_port *port)
 {
 	struct ssu100_port_private *priv;

 	priv = usb_get_serial_port_data(port);
 	kfree(priv);

 	return 0;
 }

 static int ssu100_tiocmget(struct tty_struct *tty)
 {
 	struct usb_serial_port *port = tty->driver_data;
 	struct usb_device *dev = port->serial->dev;
 	u8 *d;
 	int r;

 	d = kzalloc(2, GFP_KERNEL);
 	if (!d)
 		return -ENOMEM;

 	r = ssu100_getregister(dev, 0, UART_MCR, d);
 	if (r < 0)
 		goto mget_out;

 	r = ssu100_getregister(dev, 0, UART_MSR, d+1);
 	if (r < 0)
 		goto mget_out;

 	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) |
 		(d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) |
 		(d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) |
 		(d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) |
 		(d[1] & UART_MSR_RI ? TIOCM_RI : 0) |
 		(d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);

 mget_out:
 	kfree(d);
 	return r;
 }

 static int ssu100_tiocmset(struct tty_struct *tty,
 			   unsigned int set, unsigned int clear)
 {
 	struct usb_serial_port *port = tty->driver_data;
 	struct usb_device *dev = port->serial->dev;

 	return update_mctrl(dev, set, clear);
 }

 static void ssu100_dtr_rts(struct usb_serial_port *port, int on)
 {
 	struct usb_device *dev = port->serial->dev;

 	/* Disable flow control */
 	if (!on) {
 		if (ssu100_setregister(dev, 0, UART_MCR, 0) < 0)
 			dev_err(&port->dev, "error from flowcontrol urb\n");
 	}
 	/* drop RTS and DTR */
 	if (on)
 		set_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
 	else
 		clear_mctrl(dev, TIOCM_DTR | TIOCM_RTS);
 }

 static void ssu100_update_msr(struct usb_serial_port *port, u8 msr)
 {
 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;

 	spin_lock_irqsave(&priv->status_lock, flags);
 	priv->shadowMSR = msr;
 	spin_unlock_irqrestore(&priv->status_lock, flags);

 	if (msr & UART_MSR_ANY_DELTA) {
 		/* update input line counters */
 		if (msr & UART_MSR_DCTS)
 			port->icount.cts++;
 		if (msr & UART_MSR_DDSR)
 			port->icount.dsr++;
 		if (msr & UART_MSR_DDCD)
 			port->icount.dcd++;
 		if (msr & UART_MSR_TERI)
 			port->icount.rng++;
 		wake_up_interruptible(&port->port.delta_msr_wait);
 	}
 }

 static void ssu100_update_lsr(struct usb_serial_port *port, u8 lsr,
 			      char *tty_flag)
 {
 	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
 	unsigned long flags;

 	spin_lock_irqsave(&priv->status_lock, flags);
 	priv->shadowLSR = lsr;
 	spin_unlock_irqrestore(&priv->status_lock, flags);

 	*tty_flag = TTY_NORMAL;
 	if (lsr & UART_LSR_BRK_ERROR_BITS) {
 		/* we always want to update icount, but we only want to
 		 * update tty_flag for one case */
 		if (lsr & UART_LSR_BI) {
 			port->icount.brk++;
 			*tty_flag = TTY_BREAK;
 			usb_serial_handle_break(port);
 		}
 		if (lsr & UART_LSR_PE) {
 			port->icount.parity++;
 			if (*tty_flag == TTY_NORMAL)
 				*tty_flag = TTY_PARITY;
 		}
 		if (lsr & UART_LSR_FE) {
 			port->icount.frame++;
 			if (*tty_flag == TTY_NORMAL)
 				*tty_flag = TTY_FRAME;
 		}
 		if (lsr & UART_LSR_OE) {
 			port->icount.overrun++;
 			tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
 		}
 	}

 }

 static void ssu100_process_read_urb(struct urb *urb)
 {
 	struct usb_serial_port *port = urb->context;
 	char *packet = (char *)urb->transfer_buffer;
 	char flag = TTY_NORMAL;
 	u32 len = urb->actual_length;
 	int i;
 	char *ch;

 	if ((len >= 4) &&
 	    (packet[0] == 0x1b) && (packet[1] == 0x1b) &&
 	    ((packet[2] == 0x00) || (packet[2] == 0x01))) {
 		if (packet[2] == 0x00)
 			ssu100_update_lsr(port, packet[3], &flag);
 		if (packet[2] == 0x01)
 			ssu100_update_msr(port, packet[3]);

 		len -= 4;
 		ch = packet + 4;
 	} else
 		ch = packet;

 	if (!len)
 		return;	/* status only */

 	if (port->port.console && port->sysrq) {
 		for (i = 0; i < len; i++, ch++) {
 			if (!usb_serial_handle_sysrq_char(port, *ch))
 				tty_insert_flip_char(&port->port, *ch, flag);
 		}
 	} else
 		tty_insert_flip_string_fixed_flag(&port->port, ch, flag, len);

 	tty_flip_buffer_push(&port->port);
 }

 static struct usb_serial_driver ssu100_device = {
 	.driver = {
 		.owner = THIS_MODULE,
 		.name = "ssu100",
 	},
 	.description	     = DRIVER_DESC,
 	.id_table	     = id_table,
 	.num_ports	     = 1,
 	.open		     = ssu100_open,
 	.attach              = ssu100_attach,
 	.port_probe          = ssu100_port_probe,
 	.port_remove         = ssu100_port_remove,
 	.dtr_rts             = ssu100_dtr_rts,
 	.process_read_urb    = ssu100_process_read_urb,
 	.tiocmget            = ssu100_tiocmget,
 	.tiocmset            = ssu100_tiocmset,
 	.tiocmiwait          = usb_serial_generic_tiocmiwait,
 	.get_icount	     = usb_serial_generic_get_icount,
 	.ioctl               = ssu100_ioctl,
 	.set_termios         = ssu100_set_termios,
 };

 static struct usb_serial_driver * const serial_drivers[] = {
 	&ssu100_device, NULL
 };

 module_usb_serial_driver(serial_drivers, id_table);

 MODULE_DESCRIPTION(DRIVER_DESC);
 MODULE_LICENSE("GPL v2");
	// SPDX-License-Identifier: GPL-2.0
	/*
	* usb-serial driver for Quatech SSU-100
	*
	* based on ftdi_sio.c and the original serqt_usb.c from Quatech
	*
	*/

	#include <linux/errno.h>
	#include <linux/slab.h>
	#include <linux/tty.h>
	#include <linux/tty_driver.h>
	#include <linux/tty_flip.h>
	#include <linux/module.h>
	#include <linux/serial.h>
	#include <linux/usb.h>
	#include <linux/usb/serial.h>
	#include <linux/serial_reg.h>
	#include <linux/uaccess.h>

	#define QT_OPEN_CLOSE_CHANNEL 0xca
	#define QT_SET_GET_DEVICE 0xc2
	#define QT_SET_GET_REGISTER 0xc0
	#define QT_GET_SET_PREBUF_TRIG_LVL 0xcc
	#define QT_SET_ATF 0xcd
	#define QT_GET_SET_UART 0xc1
	#define QT_TRANSFER_IN 0xc0
	#define QT_HW_FLOW_CONTROL_MASK 0xc5
	#define QT_SW_FLOW_CONTROL_MASK 0xc6

	#define SERIAL_MSR_MASK 0xf0

	#define SERIAL_CRTSCTS ((UART_MCR_RTS << 8) \| UART_MSR_CTS)

	#define SERIAL_EVEN_PARITY (UART_LCR_PARITY \| UART_LCR_EPAR)

	#define MAX_BAUD_RATE 460800

	#define ATC_DISABLED 0x00
	#define DUPMODE_BITS 0xc0
	#define RR_BITS 0x03
	#define LOOPMODE_BITS 0x41
	#define RS232_MODE 0x00
	#define RTSCTS_TO_CONNECTOR 0x40
	#define CLKS_X4 0x02
	#define FULLPWRBIT 0x00000080
	#define NEXT_BOARD_POWER_BIT 0x00000004

	#define DRIVER_DESC "Quatech SSU-100 USB to Serial Driver"

	#define USB_VENDOR_ID_QUATECH 0x061d /* Quatech VID */
	#define QUATECH_SSU100 0xC020 /* SSU100 */

	static const struct usb_device_id id_table[] = {
	{USB_DEVICE(USB_VENDOR_ID_QUATECH, QUATECH_SSU100)},
	{} /* Terminating entry */
	};
	MODULE_DEVICE_TABLE(usb, id_table);

	struct ssu100_port_private {
	spinlock_t status_lock;
	u8 shadowLSR;
	u8 shadowMSR;
	};

	static inline int ssu100_control_msg(struct usb_device *dev,
	u8 request, u16 data, u16 index)
	{
	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
	request, 0x40, data, index,
	NULL, 0, 300);
	}

	static inline int ssu100_setdevice(struct usb_device dev, u8 data)
	{
	u16 x = ((u16)(data[1] << 8) \| (u16)(data[0]));

	return ssu100_control_msg(dev, QT_SET_GET_DEVICE, x, 0);
	}


	static inline int ssu100_getdevice(struct usb_device dev, u8 data)
	{
	int ret;

	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
	QT_SET_GET_DEVICE, 0xc0, 0, 0,
	data, 3, 300);
	if (ret < 3) {
	if (ret >= 0)
	ret = -EIO;
	}

	return ret;
	}

	static inline int ssu100_getregister(struct usb_device *dev,
	unsigned short uart,
	unsigned short reg,
	u8 *data)
	{
	int ret;

	ret = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
	QT_SET_GET_REGISTER, 0xc0, reg,
	uart, data, sizeof(*data), 300);
	if (ret < sizeof(*data)) {
	if (ret >= 0)
	ret = -EIO;
	}

	return ret;
	}


	static inline int ssu100_setregister(struct usb_device *dev,
	unsigned short uart,
	unsigned short reg,
	u16 data)
	{
	u16 value = (data << 8) \| reg;

	return usb_control_msg(dev, usb_sndctrlpipe(dev, 0),
	QT_SET_GET_REGISTER, 0x40, value, uart,
	NULL, 0, 300);

	}

	#define set_mctrl(dev, set) update_mctrl((dev), (set), 0)
	#define clear_mctrl(dev, clear) update_mctrl((dev), 0, (clear))

	/* these do not deal with device that have more than 1 port */
	static inline int update_mctrl(struct usb_device *dev, unsigned int set,
	unsigned int clear)
	{
	unsigned urb_value;
	int result;

	if (((set \| clear) & (TIOCM_DTR \| TIOCM_RTS)) == 0) {
	dev_dbg(&dev->dev, "%s - DTR\|RTS not being set\|cleared\n", __func__);
	return 0; /* no change */
	}

	clear &= ~set; /* 'set' takes precedence over 'clear' */
	urb_value = 0;
	if (set & TIOCM_DTR)
	urb_value \|= UART_MCR_DTR;
	if (set & TIOCM_RTS)
	urb_value \|= UART_MCR_RTS;

	result = ssu100_setregister(dev, 0, UART_MCR, urb_value);
	if (result < 0)
	dev_dbg(&dev->dev, "%s Error from MODEM_CTRL urb\n", __func__);

	return result;
	}

	static int ssu100_initdevice(struct usb_device *dev)
	{
	u8 *data;
	int result = 0;

	data = kzalloc(3, GFP_KERNEL);
	if (!data)
	return -ENOMEM;

	result = ssu100_getdevice(dev, data);
	if (result < 0) {
	dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
	goto out;
	}

	data[1] &= ~FULLPWRBIT;

	result = ssu100_setdevice(dev, data);
	if (result < 0) {
	dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
	goto out;
	}

	result = ssu100_control_msg(dev, QT_GET_SET_PREBUF_TRIG_LVL, 128, 0);
	if (result < 0) {
	dev_dbg(&dev->dev, "%s - set prebuffer level failed %i\n", __func__, result);
	goto out;
	}

	result = ssu100_control_msg(dev, QT_SET_ATF, ATC_DISABLED, 0);
	if (result < 0) {
	dev_dbg(&dev->dev, "%s - set ATFprebuffer level failed %i\n", __func__, result);
	goto out;
	}

	result = ssu100_getdevice(dev, data);
	if (result < 0) {
	dev_dbg(&dev->dev, "%s - get_device failed %i\n", __func__, result);
	goto out;
	}

	data[0] &= ~(RR_BITS \| DUPMODE_BITS);
	data[0] \|= CLKS_X4;
	data[1] &= ~(LOOPMODE_BITS);
	data[1] \|= RS232_MODE;

	result = ssu100_setdevice(dev, data);
	if (result < 0) {
	dev_dbg(&dev->dev, "%s - setdevice failed %i\n", __func__, result);
	goto out;
	}

	out: kfree(data);
	return result;

	}


	static void ssu100_set_termios(struct tty_struct *tty,
	struct usb_serial_port *port,
	struct ktermios *old_termios)
	{
	struct usb_device *dev = port->serial->dev;
	struct ktermios *termios = &tty->termios;
	u16 baud, divisor, remainder;
	unsigned int cflag = termios->c_cflag;
	u16 urb_value = 0; /* will hold the new flags */
	int result;

	if (cflag & PARENB) {
	if (cflag & PARODD)
	urb_value \|= UART_LCR_PARITY;
	else
	urb_value \|= SERIAL_EVEN_PARITY;
	}

	switch (cflag & CSIZE) {
	case CS5:
	urb_value \|= UART_LCR_WLEN5;
	break;
	case CS6:
	urb_value \|= UART_LCR_WLEN6;
	break;
	case CS7:
	urb_value \|= UART_LCR_WLEN7;
	break;
	default:
	case CS8:
	urb_value \|= UART_LCR_WLEN8;
	break;
	}

	baud = tty_get_baud_rate(tty);
	if (!baud)
	baud = 9600;

	dev_dbg(&port->dev, "%s - got baud = %d\n", __func__, baud);


	divisor = MAX_BAUD_RATE / baud;
	remainder = MAX_BAUD_RATE % baud;
	if (((remainder * 2) >= baud) && (baud != 110))
	divisor++;

	urb_value = urb_value << 8;

	result = ssu100_control_msg(dev, QT_GET_SET_UART, divisor, urb_value);
	if (result < 0)
	dev_dbg(&port->dev, "%s - set uart failed\n", __func__);

	if (cflag & CRTSCTS)
	result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
	SERIAL_CRTSCTS, 0);
	else
	result = ssu100_control_msg(dev, QT_HW_FLOW_CONTROL_MASK,
	0, 0);
	if (result < 0)
	dev_dbg(&port->dev, "%s - set HW flow control failed\n", __func__);

	if (I_IXOFF(tty) \|\| I_IXON(tty)) {
	u16 x = ((u16)(START_CHAR(tty) << 8) \| (u16)(STOP_CHAR(tty)));

	result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
	x, 0);
	} else
	result = ssu100_control_msg(dev, QT_SW_FLOW_CONTROL_MASK,
	0, 0);

	if (result < 0)
	dev_dbg(&port->dev, "%s - set SW flow control failed\n", __func__);

	}


	static int ssu100_open(struct tty_struct tty, struct usb_serial_port port)
	{
	struct usb_device *dev = port->serial->dev;
	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
	u8 *data;
	int result;
	unsigned long flags;

	data = kzalloc(2, GFP_KERNEL);
	if (!data)
	return -ENOMEM;

	result = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
	QT_OPEN_CLOSE_CHANNEL,
	QT_TRANSFER_IN, 0x01,
	0, data, 2, 300);
	if (result < 2) {
	dev_dbg(&port->dev, "%s - open failed %i\n", __func__, result);
	if (result >= 0)
	result = -EIO;
	kfree(data);
	return result;
	}

	spin_lock_irqsave(&priv->status_lock, flags);
	priv->shadowLSR = data[0];
	priv->shadowMSR = data[1];
	spin_unlock_irqrestore(&priv->status_lock, flags);

	kfree(data);

	/* set to 9600 */
	result = ssu100_control_msg(dev, QT_GET_SET_UART, 0x30, 0x0300);
	if (result < 0)
	dev_dbg(&port->dev, "%s - set uart failed\n", __func__);

	if (tty)
	ssu100_set_termios(tty, port, &tty->termios);

	return usb_serial_generic_open(tty, port);
	}

	static int get_serial_info(struct usb_serial_port *port,
	struct serial_struct __user *retinfo)
	{
	struct serial_struct tmp;

	memset(&tmp, 0, sizeof(tmp));
	tmp.line = port->minor;
	tmp.port = 0;
	tmp.irq = 0;
	tmp.xmit_fifo_size = port->bulk_out_size;
	tmp.baud_base = 9600;
	tmp.close_delay = 5*HZ;
	tmp.closing_wait = 30*HZ;

	if (copy_to_user(retinfo, &tmp, sizeof(*retinfo)))
	return -EFAULT;
	return 0;
	}

	static int ssu100_ioctl(struct tty_struct *tty,
	unsigned int cmd, unsigned long arg)
	{
	struct usb_serial_port *port = tty->driver_data;

	switch (cmd) {
	case TIOCGSERIAL:
	return get_serial_info(port,
	(struct serial_struct __user *) arg);
	default:
	break;
	}

	return -ENOIOCTLCMD;
	}

	static int ssu100_attach(struct usb_serial *serial)
	{
	return ssu100_initdevice(serial->dev);
	}

	static int ssu100_port_probe(struct usb_serial_port *port)
	{
	struct ssu100_port_private *priv;

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv)
	return -ENOMEM;

	spin_lock_init(&priv->status_lock);

	usb_set_serial_port_data(port, priv);

	return 0;
	}

	static int ssu100_port_remove(struct usb_serial_port *port)
	{
	struct ssu100_port_private *priv;

	priv = usb_get_serial_port_data(port);
	kfree(priv);

	return 0;
	}

	static int ssu100_tiocmget(struct tty_struct *tty)
	{
	struct usb_serial_port *port = tty->driver_data;
	struct usb_device *dev = port->serial->dev;
	u8 *d;
	int r;

	d = kzalloc(2, GFP_KERNEL);
	if (!d)
	return -ENOMEM;

	r = ssu100_getregister(dev, 0, UART_MCR, d);
	if (r < 0)
	goto mget_out;

	r = ssu100_getregister(dev, 0, UART_MSR, d+1);
	if (r < 0)
	goto mget_out;

	r = (d[0] & UART_MCR_DTR ? TIOCM_DTR : 0) \|
	(d[0] & UART_MCR_RTS ? TIOCM_RTS : 0) \|
	(d[1] & UART_MSR_CTS ? TIOCM_CTS : 0) \|
	(d[1] & UART_MSR_DCD ? TIOCM_CAR : 0) \|
	(d[1] & UART_MSR_RI ? TIOCM_RI : 0) \|
	(d[1] & UART_MSR_DSR ? TIOCM_DSR : 0);

	mget_out:
	kfree(d);
	return r;
	}

	static int ssu100_tiocmset(struct tty_struct *tty,
	unsigned int set, unsigned int clear)
	{
	struct usb_serial_port *port = tty->driver_data;
	struct usb_device *dev = port->serial->dev;

	return update_mctrl(dev, set, clear);
	}

	static void ssu100_dtr_rts(struct usb_serial_port *port, int on)
	{
	struct usb_device *dev = port->serial->dev;

	/* Disable flow control */
	if (!on) {
	if (ssu100_setregister(dev, 0, UART_MCR, 0) < 0)
	dev_err(&port->dev, "error from flowcontrol urb\n");
	}
	/* drop RTS and DTR */
	if (on)
	set_mctrl(dev, TIOCM_DTR \| TIOCM_RTS);
	else
	clear_mctrl(dev, TIOCM_DTR \| TIOCM_RTS);
	}

	static void ssu100_update_msr(struct usb_serial_port *port, u8 msr)
	{
	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;

	spin_lock_irqsave(&priv->status_lock, flags);
	priv->shadowMSR = msr;
	spin_unlock_irqrestore(&priv->status_lock, flags);

	if (msr & UART_MSR_ANY_DELTA) {
	/* update input line counters */
	if (msr & UART_MSR_DCTS)
	port->icount.cts++;
	if (msr & UART_MSR_DDSR)
	port->icount.dsr++;
	if (msr & UART_MSR_DDCD)
	port->icount.dcd++;
	if (msr & UART_MSR_TERI)
	port->icount.rng++;
	wake_up_interruptible(&port->port.delta_msr_wait);
	}
	}

	static void ssu100_update_lsr(struct usb_serial_port *port, u8 lsr,
	char *tty_flag)
	{
	struct ssu100_port_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;

	spin_lock_irqsave(&priv->status_lock, flags);
	priv->shadowLSR = lsr;
	spin_unlock_irqrestore(&priv->status_lock, flags);

	*tty_flag = TTY_NORMAL;
	if (lsr & UART_LSR_BRK_ERROR_BITS) {
	/* we always want to update icount, but we only want to
	* update tty_flag for one case */
	if (lsr & UART_LSR_BI) {
	port->icount.brk++;
	*tty_flag = TTY_BREAK;
	usb_serial_handle_break(port);
	}
	if (lsr & UART_LSR_PE) {
	port->icount.parity++;
	if (*tty_flag == TTY_NORMAL)
	*tty_flag = TTY_PARITY;
	}
	if (lsr & UART_LSR_FE) {
	port->icount.frame++;
	if (*tty_flag == TTY_NORMAL)
	*tty_flag = TTY_FRAME;
	}
	if (lsr & UART_LSR_OE) {
	port->icount.overrun++;
	tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
	}
	}

	}

	static void ssu100_process_read_urb(struct urb *urb)
	{
	struct usb_serial_port *port = urb->context;
	char packet = (char )urb->transfer_buffer;
	char flag = TTY_NORMAL;
	u32 len = urb->actual_length;
	int i;
	char *ch;

	if ((len >= 4) &&
	(packet[0] == 0x1b) && (packet[1] == 0x1b) &&
	((packet[2] == 0x00) \|\| (packet[2] == 0x01))) {
	if (packet[2] == 0x00)
	ssu100_update_lsr(port, packet[3], &flag);
	if (packet[2] == 0x01)
	ssu100_update_msr(port, packet[3]);

	len -= 4;
	ch = packet + 4;
	} else
	ch = packet;

	if (!len)
	return; /* status only */

	if (port->port.console && port->sysrq) {
	for (i = 0; i < len; i++, ch++) {
	if (!usb_serial_handle_sysrq_char(port, *ch))
	tty_insert_flip_char(&port->port, *ch, flag);
	}
	} else
	tty_insert_flip_string_fixed_flag(&port->port, ch, flag, len);

	tty_flip_buffer_push(&port->port);
	}

	static struct usb_serial_driver ssu100_device = {
	.driver = {
	.owner = THIS_MODULE,
	.name = "ssu100",
	},
	.description = DRIVER_DESC,
	.id_table = id_table,
	.num_ports = 1,
	.open = ssu100_open,
	.attach = ssu100_attach,
	.port_probe = ssu100_port_probe,
	.port_remove = ssu100_port_remove,
	.dtr_rts = ssu100_dtr_rts,
	.process_read_urb = ssu100_process_read_urb,
	.tiocmget = ssu100_tiocmget,
	.tiocmset = ssu100_tiocmset,
	.tiocmiwait = usb_serial_generic_tiocmiwait,
	.get_icount = usb_serial_generic_get_icount,
	.ioctl = ssu100_ioctl,
	.set_termios = ssu100_set_termios,
	};

	static struct usb_serial_driver * const serial_drivers[] = {
	&ssu100_device, NULL
	};

	module_usb_serial_driver(serial_drivers, id_table);

	MODULE_DESCRIPTION(DRIVER_DESC);
	MODULE_LICENSE("GPL v2");