text: /*
   * KLSI KL5KUSB105 chip RS232 converter driver
   *
   *   Copyright (C) 2010 Johan Hovold <jhovold@gmail.com>
   *   Copyright (C) 2001 Utz-Uwe Haus <haus@uuhaus.de>
   *
   *   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.
   *
   * All information about the device was acquired using SniffUSB ans snoopUSB
   * on Windows98.
   * It was written out of frustration with the PalmConnect USB Serial adapter
   * sold by Palm Inc.
   * Neither Palm, nor their contractor (MCCI) or their supplier (KLSI) provided
   * information that was not already available.
   *
   * It seems that KLSI bought some silicon-design information from ScanLogic,
   * whose SL11R processor is at the core of the KL5KUSB chipset from KLSI.
   * KLSI has firmware available for their devices; it is probable that the
   * firmware differs from that used by KLSI in their products. If you have an
   * original KLSI device and can provide some information on it, I would be
   * most interested in adding support for it here. If you have any information
   * on the protocol used (or find errors in my reverse-engineered stuff), please
   * let me know.
   *
   * The code was only tested with a PalmConnect USB adapter; if you
   * are adventurous, try it with any KLSI-based device and let me know how it
   * breaks so that I can fix it!
   */
  
  /* TODO:
   *	check modem line signals
   *	implement handshaking or decide that we do not support it
   */
  
  #include <linux/kernel.h>
  #include <linux/errno.h>
  #include <linux/init.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/uaccess.h>
  #include <asm/unaligned.h>
  #include <linux/usb.h>
  #include <linux/usb/serial.h>
  #include "kl5kusb105.h"
  
  static int debug;
  
  /*
   * Version Information
   */
  #define DRIVER_VERSION "v0.4"
  #define DRIVER_AUTHOR "Utz-Uwe Haus <haus@uuhaus.de>, Johan Hovold <jhovold@gmail.com>"
  #define DRIVER_DESC "KLSI KL5KUSB105 chipset USB->Serial Converter driver"
  
  
  /*
   * Function prototypes
   */
  static int  klsi_105_startup(struct usb_serial *serial);
  static void klsi_105_release(struct usb_serial *serial);
  static int  klsi_105_open(struct tty_struct *tty, struct usb_serial_port *port);
  static void klsi_105_close(struct usb_serial_port *port);
  static void klsi_105_set_termios(struct tty_struct *tty,
  			struct usb_serial_port *port, struct ktermios *old);
  static int  klsi_105_tiocmget(struct tty_struct *tty, struct file *file);
  static int  klsi_105_tiocmset(struct tty_struct *tty, struct file *file,
  			unsigned int set, unsigned int clear);
  static void klsi_105_process_read_urb(struct urb *urb);
  static int klsi_105_prepare_write_buffer(struct usb_serial_port *port,
  						void *dest, size_t size);
  
  /*
   * All of the device info needed for the KLSI converters.
   */
  static const struct usb_device_id id_table[] = {
  	{ USB_DEVICE(PALMCONNECT_VID, PALMCONNECT_PID) },
  	{ USB_DEVICE(KLSI_VID, KLSI_KL5KUSB105D_PID) },
  	{ }		/* Terminating entry */
  };
  
  MODULE_DEVICE_TABLE(usb, id_table);
  
  static struct usb_driver kl5kusb105d_driver = {
  	.name =		"kl5kusb105d",
  	.probe =	usb_serial_probe,
  	.disconnect =	usb_serial_disconnect,
  	.id_table =	id_table,
  	.no_dynamic_id =	1,
  };
  
  static struct usb_serial_driver kl5kusb105d_device = {
  	.driver = {
  		.owner =	THIS_MODULE,
  		.name =		"kl5kusb105d",
  	},
  	.description =		"KL5KUSB105D / PalmConnect",
  	.usb_driver =		&kl5kusb105d_driver,
  	.id_table =		id_table,
  	.num_ports =		1,
  	.bulk_out_size =	64,
  	.open =			klsi_105_open,
  	.close =		klsi_105_close,
  	.set_termios =		klsi_105_set_termios,
  	/*.break_ctl =		klsi_105_break_ctl,*/
  	.tiocmget =		klsi_105_tiocmget,
  	.tiocmset =		klsi_105_tiocmset,
  	.attach =		klsi_105_startup,
  	.release =		klsi_105_release,
  	.throttle =		usb_serial_generic_throttle,
  	.unthrottle =		usb_serial_generic_unthrottle,
  	.process_read_urb =	klsi_105_process_read_urb,
  	.prepare_write_buffer =	klsi_105_prepare_write_buffer,
  };
  
  struct klsi_105_port_settings {
  	__u8	pktlen;		/* always 5, it seems */
  	__u8	baudrate;
  	__u8	databits;
  	__u8	unknown1;
  	__u8	unknown2;
  } __attribute__ ((packed));
  
  struct klsi_105_private {
  	struct klsi_105_port_settings	cfg;
  	struct ktermios			termios;
  	unsigned long			line_state; /* modem line settings */
  	spinlock_t			lock;
  };
  
  
  /*
   * Handle vendor specific USB requests
   */
  
  
  #define KLSI_TIMEOUT	 5000 /* default urb timeout */
  
  static int klsi_105_chg_port_settings(struct usb_serial_port *port,
  				      struct klsi_105_port_settings *settings)
  {
  	int rc;
  
  	rc = usb_control_msg(port->serial->dev,
  			usb_sndctrlpipe(port->serial->dev, 0),
  			KL5KUSB105A_SIO_SET_DATA,
  			USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_INTERFACE,
  			0, /* value */
  			0, /* index */
  			settings,
  			sizeof(struct klsi_105_port_settings),
  			KLSI_TIMEOUT);
  	if (rc < 0)
  		dev_err(&port->dev,
  			"Change port settings failed (error = %d)\n", rc);
  	dev_info(&port->serial->dev->dev,
  		 "%d byte block, baudrate %x, databits %d, u1 %d, u2 %d\n",
  		 settings->pktlen, settings->baudrate, settings->databits,
  		 settings->unknown1, settings->unknown2);
  	return rc;
  }
  
  /* translate a 16-bit status value from the device to linux's TIO bits */
  static unsigned long klsi_105_status2linestate(const __u16 status)
  {
  	unsigned long res = 0;
  
  	res =   ((status & KL5KUSB105A_DSR) ? TIOCM_DSR : 0)
  	      | ((status & KL5KUSB105A_CTS) ? TIOCM_CTS : 0)
  	      ;
  
  	return res;
  }
  
  /*
   * Read line control via vendor command and return result through
   * *line_state_p
   */
  /* It seems that the status buffer has always only 2 bytes length */
  #define KLSI_STATUSBUF_LEN	2
  static int klsi_105_get_line_state(struct usb_serial_port *port,
  				   unsigned long *line_state_p)
  {
  	int rc;
  	u8 *status_buf;
  	__u16 status;
  
  	dev_info(&port->serial->dev->dev, "sending SIO Poll request\n");
  
  	status_buf = kmalloc(KLSI_STATUSBUF_LEN, GFP_KERNEL);
  	if (!status_buf) {
  		dev_err(&port->dev, "%s - out of memory for status buffer.\n",
  				__func__);
  		return -ENOMEM;
  	}
  	status_buf[0] = 0xff;
  	status_buf[1] = 0xff;
  	rc = usb_control_msg(port->serial->dev,
  			     usb_rcvctrlpipe(port->serial->dev, 0),
  			     KL5KUSB105A_SIO_POLL,
  			     USB_TYPE_VENDOR | USB_DIR_IN,
  			     0, /* value */
  			     0, /* index */
  			     status_buf, KLSI_STATUSBUF_LEN,
  			     10000
  			     );
  	if (rc < 0)
  		dev_err(&port->dev, "Reading line status failed (error = %d)\n",
  			rc);
  	else {
  		status = get_unaligned_le16(status_buf);
  
  		dev_info(&port->serial->dev->dev, "read status %x %x",
  			 status_buf[0], status_buf[1]);
  
  		*line_state_p = klsi_105_status2linestate(status);
  	}
  
  	kfree(status_buf);
  	return rc;
  }
  
  
  /*
   * Driver's tty interface functions
   */
  
  static int klsi_105_startup(struct usb_serial *serial)
  {
  	struct klsi_105_private *priv;
  	int i;
  
  
  	/* allocate the private data structure */
  	for (i = 0; i < serial->num_ports; i++) {
  		priv = kmalloc(sizeof(struct klsi_105_private),
  						   GFP_KERNEL);
  		if (!priv) {
  			dbg("%skmalloc for klsi_105_private failed.", __func__);
  			i--;
  			goto err_cleanup;
  		}
  		/* set initial values for control structures */
  		priv->cfg.pktlen    = 5;
  		priv->cfg.baudrate  = kl5kusb105a_sio_b9600;
  		priv->cfg.databits  = kl5kusb105a_dtb_8;
  		priv->cfg.unknown1  = 0;
  		priv->cfg.unknown2  = 1;
  
  		priv->line_state    = 0;
  
  		usb_set_serial_port_data(serial->port[i], priv);
  
  		spin_lock_init(&priv->lock);
  
  		/* priv->termios is left uninitialized until port opening */
  		init_waitqueue_head(&serial->port[i]->write_wait);
  	}
  
  	return 0;
  
  err_cleanup:
  	for (; i >= 0; i--) {
  		priv = usb_get_serial_port_data(serial->port[i]);
  		kfree(priv);
  		usb_set_serial_port_data(serial->port[i], NULL);
  	}
  	return -ENOMEM;
  }
  
  static void klsi_105_release(struct usb_serial *serial)
  {
  	int i;
  
  	dbg("%s", __func__);
  
  	for (i = 0; i < serial->num_ports; ++i)
  		kfree(usb_get_serial_port_data(serial->port[i]));
  }
  
  static int  klsi_105_open(struct tty_struct *tty, struct usb_serial_port *port)
  {
  	struct klsi_105_private *priv = usb_get_serial_port_data(port);
  	int retval = 0;
  	int rc;
  	int i;
  	unsigned long line_state;
  	struct klsi_105_port_settings *cfg;
  	unsigned long flags;
  
  	dbg("%s port %d", __func__, port->number);
  
  	cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
  	if (!cfg) {
  		dev_err(&port->dev, "%s - out of memory for config buffer.\n",
  				__func__);
  		return -ENOMEM;
  	}
  	cfg->pktlen   = 5;
  	cfg->baudrate = kl5kusb105a_sio_b9600;
  	cfg->databits = kl5kusb105a_dtb_8;
  	cfg->unknown1 = 0;
  	cfg->unknown2 = 1;
  	klsi_105_chg_port_settings(port, cfg);
  
  	/* set up termios structure */
  	spin_lock_irqsave(&priv->lock, flags);
  	priv->termios.c_iflag = tty->termios->c_iflag;
  	priv->termios.c_oflag = tty->termios->c_oflag;
  	priv->termios.c_cflag = tty->termios->c_cflag;
  	priv->termios.c_lflag = tty->termios->c_lflag;
  	for (i = 0; i < NCCS; i++)
  		priv->termios.c_cc[i] = tty->termios->c_cc[i];
  	priv->cfg.pktlen   = cfg->pktlen;
  	priv->cfg.baudrate = cfg->baudrate;
  	priv->cfg.databits = cfg->databits;
  	priv->cfg.unknown1 = cfg->unknown1;
  	priv->cfg.unknown2 = cfg->unknown2;
  	spin_unlock_irqrestore(&priv->lock, flags);
  
  	/* READ_ON and urb submission */
  	rc = usb_serial_generic_open(tty, port);
  	if (rc) {
  		retval = rc;
  		goto exit;
  	}
  
  	rc = usb_control_msg(port->serial->dev,
  			     usb_sndctrlpipe(port->serial->dev, 0),
  			     KL5KUSB105A_SIO_CONFIGURE,
  			     USB_TYPE_VENDOR|USB_DIR_OUT|USB_RECIP_INTERFACE,
  			     KL5KUSB105A_SIO_CONFIGURE_READ_ON,
  			     0, /* index */
  			     NULL,
  			     0,
  			     KLSI_TIMEOUT);
  	if (rc < 0) {
  		dev_err(&port->dev, "Enabling read failed (error = %d)\n", rc);
  		retval = rc;
  	} else
  		dbg("%s - enabled reading", __func__);
  
  	rc = klsi_105_get_line_state(port, &line_state);
  	if (rc >= 0) {
  		spin_lock_irqsave(&priv->lock, flags);
  		priv->line_state = line_state;
  		spin_unlock_irqrestore(&priv->lock, flags);
  		dbg("%s - read line state 0x%lx", __func__, line_state);
  		retval = 0;
  	} else
  		retval = rc;
  
  exit:
  	kfree(cfg);
  	return retval;
  }
  
  static void klsi_105_close(struct usb_serial_port *port)
  {
  	int rc;
  
  	dbg("%s port %d", __func__, port->number);
  
  	mutex_lock(&port->serial->disc_mutex);
  	if (!port->serial->disconnected) {
  		/* send READ_OFF */
  		rc = usb_control_msg(port->serial->dev,
  				     usb_sndctrlpipe(port->serial->dev, 0),
  				     KL5KUSB105A_SIO_CONFIGURE,
  				     USB_TYPE_VENDOR | USB_DIR_OUT,
  				     KL5KUSB105A_SIO_CONFIGURE_READ_OFF,
  				     0, /* index */
  				     NULL, 0,
  				     KLSI_TIMEOUT);
  		if (rc < 0)
  			dev_err(&port->dev,
  				"Disabling read failed (error = %d)\n", rc);
  	}
  	mutex_unlock(&port->serial->disc_mutex);
  
  	/* shutdown our bulk reads and writes */
  	usb_serial_generic_close(port);
  
  	/* wgg - do I need this? I think so. */
  	usb_kill_urb(port->interrupt_in_urb);
  }
  
  /* We need to write a complete 64-byte data block and encode the
   * number actually sent in the first double-byte, LSB-order. That
   * leaves at most 62 bytes of payload.
   */
  #define KLSI_HDR_LEN		2
  static int klsi_105_prepare_write_buffer(struct usb_serial_port *port,
  						void *dest, size_t size)
  {
  	unsigned char *buf = dest;
  	int count;
  
  	count = kfifo_out_locked(&port->write_fifo, buf + KLSI_HDR_LEN, size,
  								&port->lock);
  	put_unaligned_le16(count, buf);
  
  	return count + KLSI_HDR_LEN;
  }
  
  /* The data received is preceded by a length double-byte in LSB-first order.
   */
  static void klsi_105_process_read_urb(struct urb *urb)
  {
  	struct usb_serial_port *port = urb->context;
  	unsigned char *data = urb->transfer_buffer;
  	struct tty_struct *tty;
  	unsigned len;
  
  	/* empty urbs seem to happen, we ignore them */
  	if (!urb->actual_length)
  		return;
  
  	if (urb->actual_length <= KLSI_HDR_LEN) {
  		dbg("%s - malformed packet", __func__);
  		return;
  	}
  
  	tty = tty_port_tty_get(&port->port);
  	if (!tty)
  		return;
  
  	len = get_unaligned_le16(data);
  	if (len > urb->actual_length - KLSI_HDR_LEN) {
  		dbg("%s - packet length mismatch", __func__);
  		len = urb->actual_length - KLSI_HDR_LEN;
  	}
  
  	tty_insert_flip_string(tty, data + KLSI_HDR_LEN, len);
  	tty_flip_buffer_push(tty);
  	tty_kref_put(tty);
  }
  
  static void klsi_105_set_termios(struct tty_struct *tty,
  				 struct usb_serial_port *port,
  				 struct ktermios *old_termios)
  {
  	struct klsi_105_private *priv = usb_get_serial_port_data(port);
  	unsigned int iflag = tty->termios->c_iflag;
  	unsigned int old_iflag = old_termios->c_iflag;
  	unsigned int cflag = tty->termios->c_cflag;
  	unsigned int old_cflag = old_termios->c_cflag;
  	struct klsi_105_port_settings *cfg;
  	unsigned long flags;
  	speed_t baud;
  
  	cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
  	if (!cfg) {
  		dev_err(&port->dev, "%s - out of memory for config buffer.\n",
  				__func__);
  		return;
  	}
  
  	/* lock while we are modifying the settings */
  	spin_lock_irqsave(&priv->lock, flags);
  
  	/*
  	 * Update baud rate
  	 */
  	baud = tty_get_baud_rate(tty);
  
  	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
  		/* reassert DTR and (maybe) RTS on transition from B0 */
  		if ((old_cflag & CBAUD) == B0) {
  			dbg("%s: baud was B0", __func__);
  		}
  	}
  	switch (baud) {
  	case 0: /* handled below */
  		break;
  	case 1200:
  		priv->cfg.baudrate = kl5kusb105a_sio_b1200;
  		break;
  	case 2400:
  		priv->cfg.baudrate = kl5kusb105a_sio_b2400;
  		break;
  	case 4800:
  		priv->cfg.baudrate = kl5kusb105a_sio_b4800;
  		break;
  	case 9600:
  		priv->cfg.baudrate = kl5kusb105a_sio_b9600;
  		break;
  	case 19200:
  		priv->cfg.baudrate = kl5kusb105a_sio_b19200;
  		break;
  	case 38400:
  		priv->cfg.baudrate = kl5kusb105a_sio_b38400;
  		break;
  	case 57600:
  		priv->cfg.baudrate = kl5kusb105a_sio_b57600;
  		break;
  	case 115200:
  		priv->cfg.baudrate = kl5kusb105a_sio_b115200;
  		break;
  	default:
  		dbg("KLSI USB->Serial converter:"
  		    " unsupported baudrate request, using default of 9600");
  			priv->cfg.baudrate = kl5kusb105a_sio_b9600;
  		baud = 9600;
  		break;
  	}
  	if ((cflag & CBAUD) == B0) {
  		dbg("%s: baud is B0", __func__);
  		/* Drop RTS and DTR */
  		/* maybe this should be simulated by sending read
  		 * disable and read enable messages?
  		 */
  		;
  	}
  	tty_encode_baud_rate(tty, baud, baud);
  
  	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
  		/* set the number of data bits */
  		switch (cflag & CSIZE) {
  		case CS5:
  			dbg("%s - 5 bits/byte not supported", __func__);
  			spin_unlock_irqrestore(&priv->lock, flags);
  			goto err;
  		case CS6:
  			dbg("%s - 6 bits/byte not supported", __func__);
  			spin_unlock_irqrestore(&priv->lock, flags);
  			goto err;
  		case CS7:
  			priv->cfg.databits = kl5kusb105a_dtb_7;
  			break;
  		case CS8:
  			priv->cfg.databits = kl5kusb105a_dtb_8;
  			break;
  		default:
  			dev_err(&port->dev,
  				"CSIZE was not CS5-CS8, using default of 8\n");
  			priv->cfg.databits = kl5kusb105a_dtb_8;
  			break;
  		}
  	}
  
  	/*
  	 * Update line control register (LCR)
  	 */
  	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))
  	    || (cflag & CSTOPB) != (old_cflag & CSTOPB)) {
  		/* Not currently supported */
  		tty->termios->c_cflag &= ~(PARENB|PARODD|CSTOPB);
  		;
  	}
  	/*
  	 * Set flow control: well, I do not really now how to handle DTR/RTS.
  	 * Just do what we have seen with SniffUSB on Win98.
  	 */
  	if ((iflag & IXOFF) != (old_iflag & IXOFF)
  	    || (iflag & IXON) != (old_iflag & IXON)
  	    ||  (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
  		/* Not currently supported */
  		tty->termios->c_cflag &= ~CRTSCTS;
  		/* Drop DTR/RTS if no flow control otherwise assert */
  		;
  	}
  	memcpy(cfg, &priv->cfg, sizeof(*cfg));
  	spin_unlock_irqrestore(&priv->lock, flags);
  
  	/* now commit changes to device */
  	klsi_105_chg_port_settings(port, cfg);
  err:
  	kfree(cfg);
  }
  
  
  static int klsi_105_tiocmget(struct tty_struct *tty, struct file *file)
  {
  	struct usb_serial_port *port = tty->driver_data;
  	struct klsi_105_private *priv = usb_get_serial_port_data(port);
  	unsigned long flags;
  	int rc;
  	unsigned long line_state;
  	dbg("%s - request, just guessing", __func__);
  
  	rc = klsi_105_get_line_state(port, &line_state);
  	if (rc < 0) {
  		dev_err(&port->dev,
  			"Reading line control failed (error = %d)\n", rc);
  		/* better return value? EAGAIN? */
  		return rc;
  	}
  
  	spin_lock_irqsave(&priv->lock, flags);
  	priv->line_state = line_state;
  	spin_unlock_irqrestore(&priv->lock, flags);
  	dbg("%s - read line state 0x%lx", __func__, line_state);
  	return (int)line_state;
  }
  
  static int klsi_105_tiocmset(struct tty_struct *tty, struct file *file,
  			     unsigned int set, unsigned int clear)
  {
  	int retval = -EINVAL;
  
  	dbg("%s", __func__);
  
  /* if this ever gets implemented, it should be done something like this:
  	struct usb_serial *serial = port->serial;
  	struct klsi_105_private *priv = usb_get_serial_port_data(port);
  	unsigned long flags;
  	int control;
  
  	spin_lock_irqsave (&priv->lock, flags);
  	if (set & TIOCM_RTS)
  		priv->control_state |= TIOCM_RTS;
  	if (set & TIOCM_DTR)
  		priv->control_state |= TIOCM_DTR;
  	if (clear & TIOCM_RTS)
  		priv->control_state &= ~TIOCM_RTS;
  	if (clear & TIOCM_DTR)
  		priv->control_state &= ~TIOCM_DTR;
  	control = priv->control_state;
  	spin_unlock_irqrestore (&priv->lock, flags);
  	retval = mct_u232_set_modem_ctrl(serial, control);
  */
  	return retval;
  }
  
  
  static int __init klsi_105_init(void)
  {
  	int retval;
  	retval = usb_serial_register(&kl5kusb105d_device);
  	if (retval)
  		goto failed_usb_serial_register;
  	retval = usb_register(&kl5kusb105d_driver);
  	if (retval)
  		goto failed_usb_register;
  
  	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
  	       DRIVER_DESC "\n");
  	return 0;
  failed_usb_register:
  	usb_serial_deregister(&kl5kusb105d_device);
  failed_usb_serial_register:
  	return retval;
  }
  
  static void __exit klsi_105_exit(void)
  {
  	usb_deregister(&kl5kusb105d_driver);
  	usb_serial_deregister(&kl5kusb105d_device);
  }
  
  
  module_init(klsi_105_init);
  module_exit(klsi_105_exit);
  
  MODULE_AUTHOR(DRIVER_AUTHOR);
  MODULE_DESCRIPTION(DRIVER_DESC);
  MODULE_LICENSE("GPL");
  
  
  module_param(debug, bool, S_IRUGO | S_IWUSR);
  MODULE_PARM_DESC(debug, "enable extensive debugging messages");
  