xref: /openbmc/linux/drivers/usb/serial/kl5kusb105.c (revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2)
1 /*
2  * KLSI KL5KUSB105 chip RS232 converter driver
3  *
4  *   Copyright (C) 2001 Utz-Uwe Haus <haus@uuhaus.de>
5  *
6  *   This program is free software; you can redistribute it and/or modify
7  *   it under the terms of the GNU General Public License as published by
8  *   the Free Software Foundation; either version 2 of the License, or
9  *   (at your option) any later version.
10  *
11  * All information about the device was acquired using SniffUSB ans snoopUSB
12  * on Windows98.
13  * It was written out of frustration with the PalmConnect USB Serial adapter
14  * sold by Palm Inc.
15  * Neither Palm, nor their contractor (MCCI) or their supplier (KLSI) provided
16  * information that was not already available.
17  *
18  * It seems that KLSI bought some silicon-design information from ScanLogic,
19  * whose SL11R processor is at the core of the KL5KUSB chipset from KLSI.
20  * KLSI has firmware available for their devices; it is probable that the
21  * firmware differs from that used by KLSI in their products. If you have an
22  * original KLSI device and can provide some information on it, I would be
23  * most interested in adding support for it here. If you have any information
24  * on the protocol used (or find errors in my reverse-engineered stuff), please
25  * let me know.
26  *
27  * The code was only tested with a PalmConnect USB adapter; if you
28  * are adventurous, try it with any KLSI-based device and let me know how it
29  * breaks so that I can fix it!
30  */
31 
32 /* TODO:
33  *	check modem line signals
34  *	implement handshaking or decide that we do not support it
35  */
36 
37 /* History:
38  *   0.3a - implemented pools of write URBs
39  *   0.3  - alpha version for public testing
40  *   0.2  - TIOCMGET works, so autopilot(1) can be used!
41  *   0.1  - can be used to to pilot-xfer -p /dev/ttyUSB0 -l
42  *
43  *   The driver skeleton is mainly based on mct_u232.c and various other
44  *   pieces of code shamelessly copied from the drivers/usb/serial/ directory.
45  */
46 
47 
48 #include <linux/config.h>
49 #include <linux/kernel.h>
50 #include <linux/errno.h>
51 #include <linux/init.h>
52 #include <linux/slab.h>
53 #include <linux/tty.h>
54 #include <linux/tty_driver.h>
55 #include <linux/tty_flip.h>
56 #include <linux/module.h>
57 #include <asm/uaccess.h>
58 #include <linux/usb.h>
59 #include "usb-serial.h"
60 #include "kl5kusb105.h"
61 
62 static int debug;
63 
64 /*
65  * Version Information
66  */
67 #define DRIVER_VERSION "v0.3a"
68 #define DRIVER_AUTHOR "Utz-Uwe Haus <haus@uuhaus.de>"
69 #define DRIVER_DESC "KLSI KL5KUSB105 chipset USB->Serial Converter driver"
70 
71 
72 /*
73  * Function prototypes
74  */
75 static int  klsi_105_startup	         (struct usb_serial *serial);
76 static void klsi_105_shutdown	         (struct usb_serial *serial);
77 static int  klsi_105_open	         (struct usb_serial_port *port,
78 					  struct file *filp);
79 static void klsi_105_close	         (struct usb_serial_port *port,
80 					  struct file *filp);
81 static int  klsi_105_write	         (struct usb_serial_port *port,
82 					  const unsigned char *buf,
83 					  int count);
84 static void klsi_105_write_bulk_callback (struct urb *urb, struct pt_regs *regs);
85 static int  klsi_105_chars_in_buffer     (struct usb_serial_port *port);
86 static int  klsi_105_write_room          (struct usb_serial_port *port);
87 
88 static void klsi_105_read_bulk_callback  (struct urb *urb, struct pt_regs *regs);
89 static void klsi_105_set_termios         (struct usb_serial_port *port,
90 					  struct termios * old);
91 static int  klsi_105_ioctl	         (struct usb_serial_port *port,
92 					  struct file * file,
93 					  unsigned int cmd,
94 					  unsigned long arg);
95 static void klsi_105_throttle		 (struct usb_serial_port *port);
96 static void klsi_105_unthrottle		 (struct usb_serial_port *port);
97 /*
98 static void klsi_105_break_ctl	         (struct usb_serial_port *port,
99 					  int break_state );
100  */
101 static int  klsi_105_tiocmget	         (struct usb_serial_port *port,
102 					  struct file *file);
103 static int  klsi_105_tiocmset	         (struct usb_serial_port *port,
104 					  struct file *file, unsigned int set,
105 					  unsigned int clear);
106 
107 /*
108  * All of the device info needed for the KLSI converters.
109  */
110 static struct usb_device_id id_table [] = {
111 	{ USB_DEVICE(PALMCONNECT_VID, PALMCONNECT_PID) },
112 	{ USB_DEVICE(KLSI_VID, KLSI_KL5KUSB105D_PID) },
113 	{ }		/* Terminating entry */
114 };
115 
116 MODULE_DEVICE_TABLE (usb, id_table);
117 
118 static struct usb_driver kl5kusb105d_driver = {
119 	.owner =	THIS_MODULE,
120 	.name =		"kl5kusb105d",
121 	.probe =	usb_serial_probe,
122 	.disconnect =	usb_serial_disconnect,
123 	.id_table =	id_table,
124 };
125 
126 static struct usb_serial_device_type kl5kusb105d_device = {
127 	.owner =             THIS_MODULE,
128 	.name =		     "KL5KUSB105D / PalmConnect",
129 	.short_name =	     "kl5kusb105d",
130 	.id_table =	     id_table,
131 	.num_interrupt_in =  1,
132 	.num_bulk_in =	     1,
133 	.num_bulk_out =	     1,
134 	.num_ports =	     1,
135 	.open =		     klsi_105_open,
136 	.close =	     klsi_105_close,
137 	.write =	     klsi_105_write,
138 	.write_bulk_callback = klsi_105_write_bulk_callback,
139 	.chars_in_buffer =   klsi_105_chars_in_buffer,
140 	.write_room =        klsi_105_write_room,
141 	.read_bulk_callback =klsi_105_read_bulk_callback,
142 	.ioctl =	     klsi_105_ioctl,
143 	.set_termios =	     klsi_105_set_termios,
144 	/*.break_ctl =	     klsi_105_break_ctl,*/
145 	.tiocmget =          klsi_105_tiocmget,
146 	.tiocmset =          klsi_105_tiocmset,
147 	.attach =	     klsi_105_startup,
148 	.shutdown =	     klsi_105_shutdown,
149 	.throttle =	     klsi_105_throttle,
150 	.unthrottle =	     klsi_105_unthrottle,
151 };
152 
153 struct klsi_105_port_settings {
154 	__u8	pktlen;		/* always 5, it seems */
155 	__u8	baudrate;
156 	__u8	databits;
157 	__u8	unknown1;
158 	__u8	unknown2;
159 } __attribute__ ((packed));
160 
161 /* we implement a pool of NUM_URBS urbs per usb_serial */
162 #define NUM_URBS			1
163 #define URB_TRANSFER_BUFFER_SIZE	64
164 struct klsi_105_private {
165 	struct klsi_105_port_settings	cfg;
166 	struct termios			termios;
167 	unsigned long			line_state; /* modem line settings */
168 	/* write pool */
169 	struct urb *			write_urb_pool[NUM_URBS];
170 	spinlock_t			lock;
171 	unsigned long			bytes_in;
172 	unsigned long			bytes_out;
173 };
174 
175 
176 /*
177  * Handle vendor specific USB requests
178  */
179 
180 
181 #define KLSI_TIMEOUT	 5000 /* default urb timeout */
182 
183 static int klsi_105_chg_port_settings(struct usb_serial_port *port,
184 				      struct klsi_105_port_settings *settings)
185 {
186 	int rc;
187 
188         rc = usb_control_msg(port->serial->dev,
189 			     usb_sndctrlpipe(port->serial->dev, 0),
190 			     KL5KUSB105A_SIO_SET_DATA,
191                              USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_INTERFACE,
192 			     0, /* value */
193 			     0, /* index */
194 			     settings,
195 			     sizeof(struct klsi_105_port_settings),
196 			     KLSI_TIMEOUT);
197 	if (rc < 0)
198 		err("Change port settings failed (error = %d)", rc);
199 	info("%s - %d byte block, baudrate %x, databits %d, u1 %d, u2 %d",
200 	    __FUNCTION__,
201 	    settings->pktlen,
202 	    settings->baudrate, settings->databits,
203 	    settings->unknown1, settings->unknown2);
204         return rc;
205 } /* klsi_105_chg_port_settings */
206 
207 /* translate a 16-bit status value from the device to linux's TIO bits */
208 static unsigned long klsi_105_status2linestate(const __u16 status)
209 {
210 	unsigned long res = 0;
211 
212 	res =   ((status & KL5KUSB105A_DSR) ? TIOCM_DSR : 0)
213 	      | ((status & KL5KUSB105A_CTS) ? TIOCM_CTS : 0)
214 	      ;
215 
216 	return res;
217 }
218 /*
219  * Read line control via vendor command and return result through
220  * *line_state_p
221  */
222 /* It seems that the status buffer has always only 2 bytes length */
223 #define KLSI_STATUSBUF_LEN	2
224 static int klsi_105_get_line_state(struct usb_serial_port *port,
225 				   unsigned long *line_state_p)
226 {
227 	int rc;
228 	__u8 status_buf[KLSI_STATUSBUF_LEN] = { -1,-1};
229 	__u16 status;
230 
231 	info("%s - sending SIO Poll request", __FUNCTION__);
232         rc = usb_control_msg(port->serial->dev,
233 			     usb_rcvctrlpipe(port->serial->dev, 0),
234 			     KL5KUSB105A_SIO_POLL,
235                              USB_TYPE_VENDOR | USB_DIR_IN,
236 			     0, /* value */
237 			     0, /* index */
238 			     status_buf, KLSI_STATUSBUF_LEN,
239 			     10000
240 			     );
241 	if (rc < 0)
242 		err("Reading line status failed (error = %d)", rc);
243 	else {
244 		status = status_buf[0] + (status_buf[1]<<8);
245 
246 		info("%s - read status %x %x", __FUNCTION__,
247 		     status_buf[0], status_buf[1]);
248 
249 		*line_state_p = klsi_105_status2linestate(status);
250 	}
251 
252         return rc;
253 }
254 
255 
256 /*
257  * Driver's tty interface functions
258  */
259 
260 static int klsi_105_startup (struct usb_serial *serial)
261 {
262 	struct klsi_105_private *priv;
263 	int i;
264 
265 	/* check if we support the product id (see keyspan.c)
266 	 * FIXME
267 	 */
268 
269 	/* allocate the private data structure */
270 	for (i=0; i<serial->num_ports; i++) {
271 		int j;
272 		priv = kmalloc(sizeof(struct klsi_105_private),
273 						   GFP_KERNEL);
274 		if (!priv) {
275 			dbg("%skmalloc for klsi_105_private failed.", __FUNCTION__);
276 			return -ENOMEM;
277 		}
278 		/* set initial values for control structures */
279 		priv->cfg.pktlen    = 5;
280 		priv->cfg.baudrate  = kl5kusb105a_sio_b9600;
281 		priv->cfg.databits  = kl5kusb105a_dtb_8;
282 		priv->cfg.unknown1  = 0;
283 		priv->cfg.unknown2  = 1;
284 
285 		priv->line_state    = 0;
286 
287 		priv->bytes_in	    = 0;
288 		priv->bytes_out	    = 0;
289 		usb_set_serial_port_data(serial->port[i], priv);
290 
291 		spin_lock_init (&priv->lock);
292 		for (j=0; j<NUM_URBS; j++) {
293 			struct urb* urb = usb_alloc_urb(0, GFP_KERNEL);
294 
295 			priv->write_urb_pool[j] = urb;
296 			if (urb == NULL) {
297 				err("No more urbs???");
298 				continue;
299 			}
300 
301 			urb->transfer_buffer = NULL;
302 			urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE,
303 							GFP_KERNEL);
304 			if (!urb->transfer_buffer) {
305 				err("%s - out of memory for urb buffers.", __FUNCTION__);
306 				continue;
307 			}
308 		}
309 
310 		/* priv->termios is left uninitalized until port opening */
311 		init_waitqueue_head(&serial->port[i]->write_wait);
312 	}
313 
314 	return (0);
315 } /* klsi_105_startup */
316 
317 
318 static void klsi_105_shutdown (struct usb_serial *serial)
319 {
320 	int i;
321 
322 	dbg("%s", __FUNCTION__);
323 
324 	/* stop reads and writes on all ports */
325 	for (i=0; i < serial->num_ports; ++i) {
326 		struct klsi_105_private *priv = usb_get_serial_port_data(serial->port[i]);
327 		unsigned long flags;
328 
329 		if (priv) {
330 			/* kill our write urb pool */
331 			int j;
332 			struct urb **write_urbs = priv->write_urb_pool;
333 			spin_lock_irqsave(&priv->lock,flags);
334 
335 			for (j = 0; j < NUM_URBS; j++) {
336 				if (write_urbs[j]) {
337 					/* FIXME - uncomment the following
338 					 * usb_kill_urb call when the host
339 					 * controllers get fixed to set
340 					 * urb->dev = NULL after the urb is
341 					 * finished.  Otherwise this call
342 					 * oopses. */
343 					/* usb_kill_urb(write_urbs[j]); */
344 					if (write_urbs[j]->transfer_buffer)
345 						    kfree(write_urbs[j]->transfer_buffer);
346 					usb_free_urb (write_urbs[j]);
347 				}
348 			}
349 
350 			spin_unlock_irqrestore (&priv->lock, flags);
351 
352 			kfree(priv);
353 			usb_set_serial_port_data(serial->port[i], NULL);
354 		}
355 	}
356 } /* klsi_105_shutdown */
357 
358 static int  klsi_105_open (struct usb_serial_port *port, struct file *filp)
359 {
360 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
361 	int retval = 0;
362 	int rc;
363 	int i;
364 	unsigned long line_state;
365 	struct klsi_105_port_settings cfg;
366 	unsigned long flags;
367 
368 	dbg("%s port %d", __FUNCTION__, port->number);
369 
370 	/* force low_latency on so that our tty_push actually forces
371 	 * the data through
372 	 * port->tty->low_latency = 1; */
373 
374 	/* Do a defined restart:
375 	 * Set up sane default baud rate and send the 'READ_ON'
376 	 * vendor command.
377 	 * FIXME: set modem line control (how?)
378 	 * Then read the modem line control and store values in
379 	 * priv->line_state.
380 	 */
381 	cfg.pktlen   = 5;
382 	cfg.baudrate = kl5kusb105a_sio_b9600;
383 	cfg.databits = kl5kusb105a_dtb_8;
384 	cfg.unknown1 = 0;
385 	cfg.unknown2 = 1;
386 	klsi_105_chg_port_settings(port, &cfg);
387 
388 	/* set up termios structure */
389 	spin_lock_irqsave (&priv->lock, flags);
390 	priv->termios.c_iflag = port->tty->termios->c_iflag;
391 	priv->termios.c_oflag = port->tty->termios->c_oflag;
392 	priv->termios.c_cflag = port->tty->termios->c_cflag;
393 	priv->termios.c_lflag = port->tty->termios->c_lflag;
394 	for (i=0; i<NCCS; i++)
395 		priv->termios.c_cc[i] = port->tty->termios->c_cc[i];
396 	priv->cfg.pktlen   = cfg.pktlen;
397 	priv->cfg.baudrate = cfg.baudrate;
398 	priv->cfg.databits = cfg.databits;
399 	priv->cfg.unknown1 = cfg.unknown1;
400 	priv->cfg.unknown2 = cfg.unknown2;
401 	spin_unlock_irqrestore (&priv->lock, flags);
402 
403 	/* READ_ON and urb submission */
404 	usb_fill_bulk_urb(port->read_urb, port->serial->dev,
405 		      usb_rcvbulkpipe(port->serial->dev,
406 				      port->bulk_in_endpointAddress),
407 		      port->read_urb->transfer_buffer,
408 		      port->read_urb->transfer_buffer_length,
409 		      klsi_105_read_bulk_callback,
410 		      port);
411 
412 	rc = usb_submit_urb(port->read_urb, GFP_KERNEL);
413 	if (rc) {
414 		err("%s - failed submitting read urb, error %d", __FUNCTION__, rc);
415 		retval = rc;
416 		goto exit;
417 	}
418 
419 	rc = usb_control_msg(port->serial->dev,
420 			     usb_sndctrlpipe(port->serial->dev,0),
421 			     KL5KUSB105A_SIO_CONFIGURE,
422 			     USB_TYPE_VENDOR|USB_DIR_OUT|USB_RECIP_INTERFACE,
423 			     KL5KUSB105A_SIO_CONFIGURE_READ_ON,
424 			     0, /* index */
425 			     NULL,
426 			     0,
427 			     KLSI_TIMEOUT);
428 	if (rc < 0) {
429 		err("Enabling read failed (error = %d)", rc);
430 		retval = rc;
431 	} else
432 		dbg("%s - enabled reading", __FUNCTION__);
433 
434 	rc = klsi_105_get_line_state(port, &line_state);
435 	if (rc >= 0) {
436 		spin_lock_irqsave (&priv->lock, flags);
437 		priv->line_state = line_state;
438 		spin_unlock_irqrestore (&priv->lock, flags);
439 		dbg("%s - read line state 0x%lx", __FUNCTION__, line_state);
440 		retval = 0;
441 	} else
442 		retval = rc;
443 
444 exit:
445 	return retval;
446 } /* klsi_105_open */
447 
448 
449 static void klsi_105_close (struct usb_serial_port *port, struct file *filp)
450 {
451 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
452 	int rc;
453 
454 	dbg("%s port %d", __FUNCTION__, port->number);
455 
456 	/* send READ_OFF */
457 	rc = usb_control_msg (port->serial->dev,
458 			      usb_sndctrlpipe(port->serial->dev, 0),
459 			      KL5KUSB105A_SIO_CONFIGURE,
460 			      USB_TYPE_VENDOR | USB_DIR_OUT,
461 			      KL5KUSB105A_SIO_CONFIGURE_READ_OFF,
462 			      0, /* index */
463 			      NULL, 0,
464 			      KLSI_TIMEOUT);
465 	if (rc < 0)
466 		    err("Disabling read failed (error = %d)", rc);
467 
468 	/* shutdown our bulk reads and writes */
469 	usb_kill_urb(port->write_urb);
470 	usb_kill_urb(port->read_urb);
471 	/* unlink our write pool */
472 	/* FIXME */
473 	/* wgg - do I need this? I think so. */
474 	usb_kill_urb(port->interrupt_in_urb);
475 	info("kl5kusb105 port stats: %ld bytes in, %ld bytes out", priv->bytes_in, priv->bytes_out);
476 } /* klsi_105_close */
477 
478 
479 /* We need to write a complete 64-byte data block and encode the
480  * number actually sent in the first double-byte, LSB-order. That
481  * leaves at most 62 bytes of payload.
482  */
483 #define KLSI_105_DATA_OFFSET	2   /* in the bulk urb data block */
484 
485 
486 static int klsi_105_write (struct usb_serial_port *port,
487 			   const unsigned char *buf, int count)
488 {
489 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
490 	int result, size;
491 	int bytes_sent=0;
492 
493 	dbg("%s - port %d", __FUNCTION__, port->number);
494 
495 	while (count > 0) {
496 		/* try to find a free urb (write 0 bytes if none) */
497 		struct urb *urb = NULL;
498 		unsigned long flags;
499 		int i;
500 		/* since the pool is per-port we might not need the spin lock !? */
501 		spin_lock_irqsave (&priv->lock, flags);
502 		for (i=0; i<NUM_URBS; i++) {
503 			if (priv->write_urb_pool[i]->status != -EINPROGRESS) {
504 				urb = priv->write_urb_pool[i];
505 				dbg("%s - using pool URB %d", __FUNCTION__, i);
506 				break;
507 			}
508 		}
509 		spin_unlock_irqrestore (&priv->lock, flags);
510 
511 		if (urb==NULL) {
512 			dbg("%s - no more free urbs", __FUNCTION__);
513 			goto exit;
514 		}
515 
516 		if (urb->transfer_buffer == NULL) {
517 			urb->transfer_buffer = kmalloc (URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
518 			if (urb->transfer_buffer == NULL) {
519 				err("%s - no more kernel memory...", __FUNCTION__);
520 				goto exit;
521 			}
522 		}
523 
524 		size = min (count, port->bulk_out_size - KLSI_105_DATA_OFFSET);
525 		size = min (size, URB_TRANSFER_BUFFER_SIZE - KLSI_105_DATA_OFFSET);
526 
527 		memcpy (urb->transfer_buffer + KLSI_105_DATA_OFFSET, buf, size);
528 
529 		/* write payload size into transfer buffer */
530 		((__u8 *)urb->transfer_buffer)[0] = (__u8) (size & 0xFF);
531 		((__u8 *)urb->transfer_buffer)[1] = (__u8) ((size & 0xFF00)>>8);
532 
533 		/* set up our urb */
534 		usb_fill_bulk_urb(urb, port->serial->dev,
535 			      usb_sndbulkpipe(port->serial->dev,
536 					      port->bulk_out_endpointAddress),
537 			      urb->transfer_buffer,
538 			      URB_TRANSFER_BUFFER_SIZE,
539 			      klsi_105_write_bulk_callback,
540 			      port);
541 
542 		/* send the data out the bulk port */
543 		result = usb_submit_urb(urb, GFP_ATOMIC);
544 		if (result) {
545 			err("%s - failed submitting write urb, error %d", __FUNCTION__, result);
546 			goto exit;
547 		}
548 		buf += size;
549 		bytes_sent += size;
550 		count -= size;
551 	}
552 exit:
553 	/* lockless, but it's for debug info only... */
554 	priv->bytes_out+=bytes_sent;
555 
556 	return bytes_sent;	/* that's how much we wrote */
557 } /* klsi_105_write */
558 
559 static void klsi_105_write_bulk_callback ( struct urb *urb, struct pt_regs *regs)
560 {
561 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
562 
563 	dbg("%s - port %d", __FUNCTION__, port->number);
564 
565 	if (urb->status) {
566 		dbg("%s - nonzero write bulk status received: %d", __FUNCTION__,
567 		    urb->status);
568 		return;
569 	}
570 
571 	/* from generic_write_bulk_callback */
572 	schedule_work(&port->work);
573 } /* klsi_105_write_bulk_completion_callback */
574 
575 
576 /* return number of characters currently in the writing process */
577 static int klsi_105_chars_in_buffer (struct usb_serial_port *port)
578 {
579 	int chars = 0;
580 	int i;
581 	unsigned long flags;
582 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
583 
584 	spin_lock_irqsave (&priv->lock, flags);
585 
586 	for (i = 0; i < NUM_URBS; ++i) {
587 		if (priv->write_urb_pool[i]->status == -EINPROGRESS) {
588 			chars += URB_TRANSFER_BUFFER_SIZE;
589 		}
590 	}
591 
592 	spin_unlock_irqrestore (&priv->lock, flags);
593 
594 	dbg("%s - returns %d", __FUNCTION__, chars);
595 	return (chars);
596 }
597 
598 static int klsi_105_write_room (struct usb_serial_port *port)
599 {
600 	unsigned long flags;
601 	int i;
602 	int room = 0;
603 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
604 
605 	spin_lock_irqsave (&priv->lock, flags);
606 	for (i = 0; i < NUM_URBS; ++i) {
607 		if (priv->write_urb_pool[i]->status != -EINPROGRESS) {
608 			room += URB_TRANSFER_BUFFER_SIZE;
609 		}
610 	}
611 
612 	spin_unlock_irqrestore (&priv->lock, flags);
613 
614 	dbg("%s - returns %d", __FUNCTION__, room);
615 	return (room);
616 }
617 
618 
619 
620 static void klsi_105_read_bulk_callback (struct urb *urb, struct pt_regs *regs)
621 {
622 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
623 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
624 	struct tty_struct *tty;
625 	unsigned char *data = urb->transfer_buffer;
626 	int rc;
627 
628         dbg("%s - port %d", __FUNCTION__, port->number);
629 
630 	/* The urb might have been killed. */
631         if (urb->status) {
632                 dbg("%s - nonzero read bulk status received: %d", __FUNCTION__,
633 		    urb->status);
634                 return;
635         }
636 
637 	/* The data received is again preceded by a length double-byte in LSB-
638 	 * first order (see klsi_105_write() )
639 	 */
640 	if (urb->actual_length == 0) {
641 		/* empty urbs seem to happen, we ignore them */
642 		/* dbg("%s - emtpy URB", __FUNCTION__); */
643 	       ;
644 	} else if (urb->actual_length <= 2) {
645 		dbg("%s - size %d URB not understood", __FUNCTION__,
646 		    urb->actual_length);
647 		usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
648 				      urb->actual_length, data);
649 	} else {
650 		int i;
651 		int bytes_sent = ((__u8 *) data)[0] +
652 				 ((unsigned int) ((__u8 *) data)[1] << 8);
653 		tty = port->tty;
654 		/* we should immediately resubmit the URB, before attempting
655 		 * to pass the data on to the tty layer. But that needs locking
656 		 * against re-entry an then mixed-up data because of
657 		 * intermixed tty_flip_buffer_push()s
658 		 * FIXME
659 		 */
660 		usb_serial_debug_data(debug, &port->dev, __FUNCTION__,
661 				      urb->actual_length, data);
662 
663 		if (bytes_sent + 2 > urb->actual_length) {
664 			dbg("%s - trying to read more data than available"
665 			    " (%d vs. %d)", __FUNCTION__,
666 			    bytes_sent+2, urb->actual_length);
667 			/* cap at implied limit */
668 			bytes_sent = urb->actual_length - 2;
669 		}
670 
671 		for (i = 2; i < 2+bytes_sent; i++) {
672 			/* if we insert more than TTY_FLIPBUF_SIZE characters,
673 			 * we drop them. */
674 			if(tty->flip.count >= TTY_FLIPBUF_SIZE) {
675 				tty_flip_buffer_push(tty);
676 			}
677 			/* this doesn't actually push the data through unless
678 			 * tty->low_latency is set */
679 			tty_insert_flip_char(tty, ((__u8*) data)[i], 0);
680 		}
681 		tty_flip_buffer_push(tty);
682 
683 		/* again lockless, but debug info only */
684 		priv->bytes_in += bytes_sent;
685 	}
686 	/* Continue trying to always read  */
687 	usb_fill_bulk_urb(port->read_urb, port->serial->dev,
688 		      usb_rcvbulkpipe(port->serial->dev,
689 				      port->bulk_in_endpointAddress),
690 		      port->read_urb->transfer_buffer,
691 		      port->read_urb->transfer_buffer_length,
692 		      klsi_105_read_bulk_callback,
693 		      port);
694 	rc = usb_submit_urb(port->read_urb, GFP_ATOMIC);
695 	if (rc)
696 		err("%s - failed resubmitting read urb, error %d", __FUNCTION__, rc);
697 } /* klsi_105_read_bulk_callback */
698 
699 
700 static void klsi_105_set_termios (struct usb_serial_port *port,
701 				  struct termios *old_termios)
702 {
703 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
704 	unsigned int iflag = port->tty->termios->c_iflag;
705 	unsigned int old_iflag = old_termios->c_iflag;
706 	unsigned int cflag = port->tty->termios->c_cflag;
707 	unsigned int old_cflag = old_termios->c_cflag;
708 	struct klsi_105_port_settings cfg;
709 	unsigned long flags;
710 
711 	/* lock while we are modifying the settings */
712 	spin_lock_irqsave (&priv->lock, flags);
713 
714 	/*
715 	 * Update baud rate
716 	 */
717 	if( (cflag & CBAUD) != (old_cflag & CBAUD) ) {
718 	        /* reassert DTR and (maybe) RTS on transition from B0 */
719 		if( (old_cflag & CBAUD) == B0 ) {
720 			dbg("%s: baud was B0", __FUNCTION__);
721 #if 0
722 			priv->control_state |= TIOCM_DTR;
723 			/* don't set RTS if using hardware flow control */
724 			if (!(old_cflag & CRTSCTS)) {
725 				priv->control_state |= TIOCM_RTS;
726 			}
727 			mct_u232_set_modem_ctrl(serial, priv->control_state);
728 #endif
729 		}
730 
731 		switch(cflag & CBAUD) {
732 		case B0: /* handled below */
733 			break;
734 		case B1200: priv->cfg.baudrate = kl5kusb105a_sio_b1200;
735 			break;
736 		case B2400: priv->cfg.baudrate = kl5kusb105a_sio_b2400;
737 			break;
738 		case B4800: priv->cfg.baudrate = kl5kusb105a_sio_b4800;
739 			break;
740 		case B9600: priv->cfg.baudrate = kl5kusb105a_sio_b9600;
741 			break;
742 		case B19200: priv->cfg.baudrate = kl5kusb105a_sio_b19200;
743 			break;
744 		case B38400: priv->cfg.baudrate = kl5kusb105a_sio_b38400;
745 			break;
746 		case B57600: priv->cfg.baudrate = kl5kusb105a_sio_b57600;
747 			break;
748 		case B115200: priv->cfg.baudrate = kl5kusb105a_sio_b115200;
749 			break;
750 		default:
751 			err("KLSI USB->Serial converter:"
752 			    " unsupported baudrate request, using default"
753 			    " of 9600");
754 			priv->cfg.baudrate = kl5kusb105a_sio_b9600;
755 			break;
756 		}
757 		if ((cflag & CBAUD) == B0 ) {
758 			dbg("%s: baud is B0", __FUNCTION__);
759 			/* Drop RTS and DTR */
760 			/* maybe this should be simulated by sending read
761 			 * disable and read enable messages?
762 			 */
763 			;
764 #if 0
765 			priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
766         		mct_u232_set_modem_ctrl(serial, priv->control_state);
767 #endif
768 		}
769 	}
770 
771 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
772 		/* set the number of data bits */
773 		switch (cflag & CSIZE) {
774 		case CS5:
775 			dbg("%s - 5 bits/byte not supported", __FUNCTION__);
776 			spin_unlock_irqrestore (&priv->lock, flags);
777 			return ;
778 		case CS6:
779 			dbg("%s - 6 bits/byte not supported", __FUNCTION__);
780 			spin_unlock_irqrestore (&priv->lock, flags);
781 			return ;
782 		case CS7:
783 			priv->cfg.databits = kl5kusb105a_dtb_7;
784 			break;
785 		case CS8:
786 			priv->cfg.databits = kl5kusb105a_dtb_8;
787 			break;
788 		default:
789 			err("CSIZE was not CS5-CS8, using default of 8");
790 			priv->cfg.databits = kl5kusb105a_dtb_8;
791 			break;
792 		}
793 	}
794 
795 	/*
796 	 * Update line control register (LCR)
797 	 */
798 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))
799 	    || (cflag & CSTOPB) != (old_cflag & CSTOPB) ) {
800 
801 #if 0
802 		priv->last_lcr = 0;
803 
804 		/* set the parity */
805 		if (cflag & PARENB)
806 			priv->last_lcr |= (cflag & PARODD) ?
807 				MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
808 		else
809 			priv->last_lcr |= MCT_U232_PARITY_NONE;
810 
811 		/* set the number of stop bits */
812 		priv->last_lcr |= (cflag & CSTOPB) ?
813 			MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
814 
815 		mct_u232_set_line_ctrl(serial, priv->last_lcr);
816 #endif
817 		;
818 	}
819 
820 	/*
821 	 * Set flow control: well, I do not really now how to handle DTR/RTS.
822 	 * Just do what we have seen with SniffUSB on Win98.
823 	 */
824 	if( (iflag & IXOFF) != (old_iflag & IXOFF)
825 	    || (iflag & IXON) != (old_iflag & IXON)
826 	    ||  (cflag & CRTSCTS) != (old_cflag & CRTSCTS) ) {
827 
828 		/* Drop DTR/RTS if no flow control otherwise assert */
829 #if 0
830 		if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS) )
831 			priv->control_state |= TIOCM_DTR | TIOCM_RTS;
832 		else
833 			priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
834 		mct_u232_set_modem_ctrl(serial, priv->control_state);
835 #endif
836 		;
837 	}
838 	memcpy (&cfg, &priv->cfg, sizeof(cfg));
839 	spin_unlock_irqrestore (&priv->lock, flags);
840 
841 	/* now commit changes to device */
842 	klsi_105_chg_port_settings(port, &cfg);
843 } /* klsi_105_set_termios */
844 
845 
846 #if 0
847 static void mct_u232_break_ctl( struct usb_serial_port *port, int break_state )
848 {
849 	struct usb_serial *serial = port->serial;
850 	struct mct_u232_private *priv = (struct mct_u232_private *)port->private;
851 	unsigned char lcr = priv->last_lcr;
852 
853 	dbg("%sstate=%d", __FUNCTION__, break_state);
854 
855 	if (break_state)
856 		lcr |= MCT_U232_SET_BREAK;
857 
858 	mct_u232_set_line_ctrl(serial, lcr);
859 } /* mct_u232_break_ctl */
860 #endif
861 
862 static int klsi_105_tiocmget (struct usb_serial_port *port, struct file *file)
863 {
864 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
865 	unsigned long flags;
866 	int rc;
867 	unsigned long line_state;
868 	dbg("%s - request, just guessing", __FUNCTION__);
869 
870 	rc = klsi_105_get_line_state(port, &line_state);
871 	if (rc < 0) {
872 		err("Reading line control failed (error = %d)", rc);
873 		/* better return value? EAGAIN? */
874 		return rc;
875 	}
876 
877 	spin_lock_irqsave (&priv->lock, flags);
878 	priv->line_state = line_state;
879 	spin_unlock_irqrestore (&priv->lock, flags);
880 	dbg("%s - read line state 0x%lx", __FUNCTION__, line_state);
881 	return (int)line_state;
882 }
883 
884 static int klsi_105_tiocmset (struct usb_serial_port *port, struct file *file,
885 			      unsigned int set, unsigned int clear)
886 {
887 	int retval = -EINVAL;
888 
889 	dbg("%s", __FUNCTION__);
890 
891 /* if this ever gets implemented, it should be done something like this:
892 	struct usb_serial *serial = port->serial;
893 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
894 	unsigned long flags;
895 	int control;
896 
897 	spin_lock_irqsave (&priv->lock, flags);
898 	if (set & TIOCM_RTS)
899 		priv->control_state |= TIOCM_RTS;
900 	if (set & TIOCM_DTR)
901 		priv->control_state |= TIOCM_DTR;
902 	if (clear & TIOCM_RTS)
903 		priv->control_state &= ~TIOCM_RTS;
904 	if (clear & TIOCM_DTR)
905 		priv->control_state &= ~TIOCM_DTR;
906 	control = priv->control_state;
907 	spin_unlock_irqrestore (&priv->lock, flags);
908 	retval = mct_u232_set_modem_ctrl(serial, control);
909 */
910 	return retval;
911 }
912 
913 static int klsi_105_ioctl (struct usb_serial_port *port, struct file * file,
914 			   unsigned int cmd, unsigned long arg)
915 {
916 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
917 	void __user *user_arg = (void __user *)arg;
918 
919 	dbg("%scmd=0x%x", __FUNCTION__, cmd);
920 
921 	/* Based on code from acm.c and others */
922 	switch (cmd) {
923 	case TIOCMIWAIT:
924 		/* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
925 		/* TODO */
926 		dbg("%s - TIOCMIWAIT not handled", __FUNCTION__);
927 		return -ENOIOCTLCMD;
928 	case TIOCGICOUNT:
929 		/* return count of modemline transitions */
930 		/* TODO */
931 		dbg("%s - TIOCGICOUNT not handled", __FUNCTION__);
932 		return -ENOIOCTLCMD;
933 	case TCGETS:
934 		/* return current info to caller */
935 		dbg("%s - TCGETS data faked/incomplete", __FUNCTION__);
936 
937 		if (!access_ok(VERIFY_WRITE, user_arg, sizeof(struct termios)))
938 			return -EFAULT;
939 
940 		if (kernel_termios_to_user_termios((struct termios __user *)arg,
941 						   &priv->termios))
942 			return -EFAULT;
943 		return 0;
944 	case TCSETS:
945 		/* set port termios to the one given by the user */
946 		dbg("%s - TCSETS not handled", __FUNCTION__);
947 
948 		if (!access_ok(VERIFY_READ, user_arg, sizeof(struct termios)))
949 			return -EFAULT;
950 
951 		if (user_termios_to_kernel_termios(&priv->termios,
952 						   (struct termios __user *)arg))
953 			return -EFAULT;
954 		klsi_105_set_termios(port, &priv->termios);
955 		return 0;
956 	case TCSETSW: {
957 		/* set port termios and try to wait for completion of last
958 		 * write operation */
959 		/* We guess here. If there are not too many write urbs
960 		 * outstanding, we lie. */
961 		/* what is the right way to wait here? schedule() ? */
962 	        /*
963 		while (klsi_105_chars_in_buffer(port) > (NUM_URBS / 4 ) * URB_TRANSFER_BUFFER_SIZE)
964 			    schedule();
965 		 */
966 		return -ENOIOCTLCMD;
967 		      }
968 	default:
969 		dbg("%s: arg not supported - 0x%04x", __FUNCTION__,cmd);
970 		return(-ENOIOCTLCMD);
971 		break;
972 	}
973 	return 0;
974 } /* klsi_105_ioctl */
975 
976 static void klsi_105_throttle (struct usb_serial_port *port)
977 {
978 	dbg("%s - port %d", __FUNCTION__, port->number);
979 	usb_kill_urb(port->read_urb);
980 }
981 
982 static void klsi_105_unthrottle (struct usb_serial_port *port)
983 {
984 	int result;
985 
986 	dbg("%s - port %d", __FUNCTION__, port->number);
987 
988 	port->read_urb->dev = port->serial->dev;
989 	result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
990 	if (result)
991 		err("%s - failed submitting read urb, error %d", __FUNCTION__,
992 		    result);
993 }
994 
995 
996 
997 static int __init klsi_105_init (void)
998 {
999 	int retval;
1000 	retval = usb_serial_register(&kl5kusb105d_device);
1001 	if (retval)
1002 		goto failed_usb_serial_register;
1003 	retval = usb_register(&kl5kusb105d_driver);
1004 	if (retval)
1005 		goto failed_usb_register;
1006 
1007 	info(DRIVER_DESC " " DRIVER_VERSION);
1008 	return 0;
1009 failed_usb_register:
1010 	usb_serial_deregister(&kl5kusb105d_device);
1011 failed_usb_serial_register:
1012 	return retval;
1013 }
1014 
1015 
1016 static void __exit klsi_105_exit (void)
1017 {
1018 	usb_deregister (&kl5kusb105d_driver);
1019 	usb_serial_deregister (&kl5kusb105d_device);
1020 }
1021 
1022 
1023 module_init (klsi_105_init);
1024 module_exit (klsi_105_exit);
1025 
1026 MODULE_AUTHOR( DRIVER_AUTHOR );
1027 MODULE_DESCRIPTION( DRIVER_DESC );
1028 MODULE_LICENSE("GPL");
1029 
1030 
1031 module_param(debug, bool, S_IRUGO | S_IWUSR);
1032 MODULE_PARM_DESC(debug, "enable extensive debugging messages");
1033 
1034 /* vim: set sts=8 ts=8 sw=8: */
1035