xref: /openbmc/linux/drivers/usb/serial/kl5kusb105.c (revision 545e4006)
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/kernel.h>
49 #include <linux/errno.h>
50 #include <linux/init.h>
51 #include <linux/slab.h>
52 #include <linux/tty.h>
53 #include <linux/tty_driver.h>
54 #include <linux/tty_flip.h>
55 #include <linux/module.h>
56 #include <linux/uaccess.h>
57 #include <asm/unaligned.h>
58 #include <linux/usb.h>
59 #include <linux/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 tty_struct *tty,
78 			struct usb_serial_port *port, struct file *filp);
79 static void klsi_105_close(struct tty_struct *tty,
80 			struct usb_serial_port *port, struct file *filp);
81 static int  klsi_105_write(struct tty_struct *tty,
82 	struct usb_serial_port *port, const unsigned char *buf, int count);
83 static void klsi_105_write_bulk_callback(struct urb *urb);
84 static int  klsi_105_chars_in_buffer(struct tty_struct *tty);
85 static int  klsi_105_write_room(struct tty_struct *tty);
86 static void klsi_105_read_bulk_callback(struct urb *urb);
87 static void klsi_105_set_termios(struct tty_struct *tty,
88 			struct usb_serial_port *port, struct ktermios *old);
89 static void klsi_105_throttle(struct tty_struct *tty);
90 static void klsi_105_unthrottle(struct tty_struct *tty);
91 static int  klsi_105_tiocmget(struct tty_struct *tty, struct file *file);
92 static int  klsi_105_tiocmset(struct tty_struct *tty, struct file *file,
93 			unsigned int set, unsigned int clear);
94 
95 /*
96  * All of the device info needed for the KLSI converters.
97  */
98 static struct usb_device_id id_table [] = {
99 	{ USB_DEVICE(PALMCONNECT_VID, PALMCONNECT_PID) },
100 	{ USB_DEVICE(KLSI_VID, KLSI_KL5KUSB105D_PID) },
101 	{ }		/* Terminating entry */
102 };
103 
104 MODULE_DEVICE_TABLE(usb, id_table);
105 
106 static struct usb_driver kl5kusb105d_driver = {
107 	.name =		"kl5kusb105d",
108 	.probe =	usb_serial_probe,
109 	.disconnect =	usb_serial_disconnect,
110 	.id_table =	id_table,
111 	.no_dynamic_id = 	1,
112 };
113 
114 static struct usb_serial_driver kl5kusb105d_device = {
115 	.driver = {
116 		.owner =	THIS_MODULE,
117 		.name =		"kl5kusb105d",
118 	},
119 	.description =	     "KL5KUSB105D / PalmConnect",
120 	.usb_driver =	     &kl5kusb105d_driver,
121 	.id_table =	     id_table,
122 	.num_ports =	     1,
123 	.open =		     klsi_105_open,
124 	.close =	     klsi_105_close,
125 	.write =	     klsi_105_write,
126 	.write_bulk_callback = klsi_105_write_bulk_callback,
127 	.chars_in_buffer =   klsi_105_chars_in_buffer,
128 	.write_room =        klsi_105_write_room,
129 	.read_bulk_callback = klsi_105_read_bulk_callback,
130 	.set_termios =	     klsi_105_set_termios,
131 	/*.break_ctl =	     klsi_105_break_ctl,*/
132 	.tiocmget =          klsi_105_tiocmget,
133 	.tiocmset =          klsi_105_tiocmset,
134 	.attach =	     klsi_105_startup,
135 	.shutdown =	     klsi_105_shutdown,
136 	.throttle =	     klsi_105_throttle,
137 	.unthrottle =	     klsi_105_unthrottle,
138 };
139 
140 struct klsi_105_port_settings {
141 	__u8	pktlen;		/* always 5, it seems */
142 	__u8	baudrate;
143 	__u8	databits;
144 	__u8	unknown1;
145 	__u8	unknown2;
146 } __attribute__ ((packed));
147 
148 /* we implement a pool of NUM_URBS urbs per usb_serial */
149 #define NUM_URBS			1
150 #define URB_TRANSFER_BUFFER_SIZE	64
151 struct klsi_105_private {
152 	struct klsi_105_port_settings	cfg;
153 	struct ktermios			termios;
154 	unsigned long			line_state; /* modem line settings */
155 	/* write pool */
156 	struct urb			*write_urb_pool[NUM_URBS];
157 	spinlock_t			lock;
158 	unsigned long			bytes_in;
159 	unsigned long			bytes_out;
160 };
161 
162 
163 /*
164  * Handle vendor specific USB requests
165  */
166 
167 
168 #define KLSI_TIMEOUT	 5000 /* default urb timeout */
169 
170 static int klsi_105_chg_port_settings(struct usb_serial_port *port,
171 				      struct klsi_105_port_settings *settings)
172 {
173 	int rc;
174 
175 	rc = usb_control_msg(port->serial->dev,
176 			usb_sndctrlpipe(port->serial->dev, 0),
177 			KL5KUSB105A_SIO_SET_DATA,
178 			USB_TYPE_VENDOR | USB_DIR_OUT | USB_RECIP_INTERFACE,
179 			0, /* value */
180 			0, /* index */
181 			settings,
182 			sizeof(struct klsi_105_port_settings),
183 			KLSI_TIMEOUT);
184 	if (rc < 0)
185 		err("Change port settings failed (error = %d)", rc);
186 	info("%s - %d byte block, baudrate %x, databits %d, u1 %d, u2 %d",
187 	    __func__,
188 	    settings->pktlen,
189 	    settings->baudrate, settings->databits,
190 	    settings->unknown1, settings->unknown2);
191 	return rc;
192 } /* klsi_105_chg_port_settings */
193 
194 /* translate a 16-bit status value from the device to linux's TIO bits */
195 static unsigned long klsi_105_status2linestate(const __u16 status)
196 {
197 	unsigned long res = 0;
198 
199 	res =   ((status & KL5KUSB105A_DSR) ? TIOCM_DSR : 0)
200 	      | ((status & KL5KUSB105A_CTS) ? TIOCM_CTS : 0)
201 	      ;
202 
203 	return res;
204 }
205 /*
206  * Read line control via vendor command and return result through
207  * *line_state_p
208  */
209 /* It seems that the status buffer has always only 2 bytes length */
210 #define KLSI_STATUSBUF_LEN	2
211 static int klsi_105_get_line_state(struct usb_serial_port *port,
212 				   unsigned long *line_state_p)
213 {
214 	int rc;
215 	__u8 status_buf[KLSI_STATUSBUF_LEN] = { -1, -1};
216 	__u16 status;
217 
218 	info("%s - sending SIO Poll request", __func__);
219 	rc = usb_control_msg(port->serial->dev,
220 			     usb_rcvctrlpipe(port->serial->dev, 0),
221 			     KL5KUSB105A_SIO_POLL,
222 			     USB_TYPE_VENDOR | USB_DIR_IN,
223 			     0, /* value */
224 			     0, /* index */
225 			     status_buf, KLSI_STATUSBUF_LEN,
226 			     10000
227 			     );
228 	if (rc < 0)
229 		err("Reading line status failed (error = %d)", rc);
230 	else {
231 		status = get_unaligned_le16(status_buf);
232 
233 		info("%s - read status %x %x", __func__,
234 		     status_buf[0], status_buf[1]);
235 
236 		*line_state_p = klsi_105_status2linestate(status);
237 	}
238 	return rc;
239 }
240 
241 
242 /*
243  * Driver's tty interface functions
244  */
245 
246 static int klsi_105_startup(struct usb_serial *serial)
247 {
248 	struct klsi_105_private *priv;
249 	int i, j;
250 
251 	/* check if we support the product id (see keyspan.c)
252 	 * FIXME
253 	 */
254 
255 	/* allocate the private data structure */
256 	for (i = 0; i < serial->num_ports; i++) {
257 		priv = kmalloc(sizeof(struct klsi_105_private),
258 						   GFP_KERNEL);
259 		if (!priv) {
260 			dbg("%skmalloc for klsi_105_private failed.", __func__);
261 			i--;
262 			goto err_cleanup;
263 		}
264 		/* set initial values for control structures */
265 		priv->cfg.pktlen    = 5;
266 		priv->cfg.baudrate  = kl5kusb105a_sio_b9600;
267 		priv->cfg.databits  = kl5kusb105a_dtb_8;
268 		priv->cfg.unknown1  = 0;
269 		priv->cfg.unknown2  = 1;
270 
271 		priv->line_state    = 0;
272 
273 		priv->bytes_in	    = 0;
274 		priv->bytes_out	    = 0;
275 		usb_set_serial_port_data(serial->port[i], priv);
276 
277 		spin_lock_init(&priv->lock);
278 		for (j = 0; j < NUM_URBS; j++) {
279 			struct urb *urb = usb_alloc_urb(0, GFP_KERNEL);
280 
281 			priv->write_urb_pool[j] = urb;
282 			if (urb == NULL) {
283 				err("No more urbs???");
284 				goto err_cleanup;
285 			}
286 
287 			urb->transfer_buffer =
288 				kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_KERNEL);
289 			if (!urb->transfer_buffer) {
290 				err("%s - out of memory for urb buffers.",
291 								__func__);
292 				goto err_cleanup;
293 			}
294 		}
295 
296 		/* priv->termios is left uninitalized until port opening */
297 		init_waitqueue_head(&serial->port[i]->write_wait);
298 	}
299 
300 	return 0;
301 
302 err_cleanup:
303 	for (; i >= 0; i--) {
304 		priv = usb_get_serial_port_data(serial->port[i]);
305 		for (j = 0; j < NUM_URBS; j++) {
306 			if (priv->write_urb_pool[j]) {
307 				kfree(priv->write_urb_pool[j]->transfer_buffer);
308 				usb_free_urb(priv->write_urb_pool[j]);
309 			}
310 		}
311 		usb_set_serial_port_data(serial->port[i], NULL);
312 	}
313 	return -ENOMEM;
314 } /* klsi_105_startup */
315 
316 
317 static void klsi_105_shutdown(struct usb_serial *serial)
318 {
319 	int i;
320 
321 	dbg("%s", __func__);
322 
323 	/* stop reads and writes on all ports */
324 	for (i = 0; i < serial->num_ports; ++i) {
325 		struct klsi_105_private *priv =
326 				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 					kfree(write_urbs[j]->transfer_buffer);
345 					usb_free_urb(write_urbs[j]);
346 				}
347 			}
348 			spin_unlock_irqrestore(&priv->lock, flags);
349 			kfree(priv);
350 			usb_set_serial_port_data(serial->port[i], NULL);
351 		}
352 	}
353 } /* klsi_105_shutdown */
354 
355 static int  klsi_105_open(struct tty_struct *tty,
356 			struct usb_serial_port *port, struct file *filp)
357 {
358 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
359 	int retval = 0;
360 	int rc;
361 	int i;
362 	unsigned long line_state;
363 	struct klsi_105_port_settings cfg;
364 	unsigned long flags;
365 
366 	dbg("%s port %d", __func__, port->number);
367 
368 	/* force low_latency on so that our tty_push actually forces
369 	 * the data through
370 	 * tty->low_latency = 1; */
371 
372 	/* Do a defined restart:
373 	 * Set up sane default baud rate and send the 'READ_ON'
374 	 * vendor command.
375 	 * FIXME: set modem line control (how?)
376 	 * Then read the modem line control and store values in
377 	 * priv->line_state.
378 	 */
379 	cfg.pktlen   = 5;
380 	cfg.baudrate = kl5kusb105a_sio_b9600;
381 	cfg.databits = kl5kusb105a_dtb_8;
382 	cfg.unknown1 = 0;
383 	cfg.unknown2 = 1;
384 	klsi_105_chg_port_settings(port, &cfg);
385 
386 	/* set up termios structure */
387 	spin_lock_irqsave(&priv->lock, flags);
388 	priv->termios.c_iflag = tty->termios->c_iflag;
389 	priv->termios.c_oflag = tty->termios->c_oflag;
390 	priv->termios.c_cflag = tty->termios->c_cflag;
391 	priv->termios.c_lflag = tty->termios->c_lflag;
392 	for (i = 0; i < NCCS; i++)
393 		priv->termios.c_cc[i] = tty->termios->c_cc[i];
394 	priv->cfg.pktlen   = cfg.pktlen;
395 	priv->cfg.baudrate = cfg.baudrate;
396 	priv->cfg.databits = cfg.databits;
397 	priv->cfg.unknown1 = cfg.unknown1;
398 	priv->cfg.unknown2 = cfg.unknown2;
399 	spin_unlock_irqrestore(&priv->lock, flags);
400 
401 	/* READ_ON and urb submission */
402 	usb_fill_bulk_urb(port->read_urb, port->serial->dev,
403 		      usb_rcvbulkpipe(port->serial->dev,
404 				      port->bulk_in_endpointAddress),
405 		      port->read_urb->transfer_buffer,
406 		      port->read_urb->transfer_buffer_length,
407 		      klsi_105_read_bulk_callback,
408 		      port);
409 
410 	rc = usb_submit_urb(port->read_urb, GFP_KERNEL);
411 	if (rc) {
412 		err("%s - failed submitting read urb, error %d", __func__, rc);
413 		retval = rc;
414 		goto exit;
415 	}
416 
417 	rc = usb_control_msg(port->serial->dev,
418 			     usb_sndctrlpipe(port->serial->dev, 0),
419 			     KL5KUSB105A_SIO_CONFIGURE,
420 			     USB_TYPE_VENDOR|USB_DIR_OUT|USB_RECIP_INTERFACE,
421 			     KL5KUSB105A_SIO_CONFIGURE_READ_ON,
422 			     0, /* index */
423 			     NULL,
424 			     0,
425 			     KLSI_TIMEOUT);
426 	if (rc < 0) {
427 		err("Enabling read failed (error = %d)", rc);
428 		retval = rc;
429 	} else
430 		dbg("%s - enabled reading", __func__);
431 
432 	rc = klsi_105_get_line_state(port, &line_state);
433 	if (rc >= 0) {
434 		spin_lock_irqsave(&priv->lock, flags);
435 		priv->line_state = line_state;
436 		spin_unlock_irqrestore(&priv->lock, flags);
437 		dbg("%s - read line state 0x%lx", __func__, line_state);
438 		retval = 0;
439 	} else
440 		retval = rc;
441 
442 exit:
443 	return retval;
444 } /* klsi_105_open */
445 
446 
447 static void klsi_105_close(struct tty_struct *tty,
448 			struct usb_serial_port *port, struct file *filp)
449 {
450 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
451 	int rc;
452 
453 	dbg("%s port %d", __func__, port->number);
454 
455 	mutex_lock(&port->serial->disc_mutex);
456 	if (!port->serial->disconnected) {
457 		/* send READ_OFF */
458 		rc = usb_control_msg(port->serial->dev,
459 				     usb_sndctrlpipe(port->serial->dev, 0),
460 				     KL5KUSB105A_SIO_CONFIGURE,
461 				     USB_TYPE_VENDOR | USB_DIR_OUT,
462 				     KL5KUSB105A_SIO_CONFIGURE_READ_OFF,
463 				     0, /* index */
464 				     NULL, 0,
465 				     KLSI_TIMEOUT);
466 		if (rc < 0)
467 			err("Disabling read failed (error = %d)", rc);
468 	}
469 	mutex_unlock(&port->serial->disc_mutex);
470 
471 	/* shutdown our bulk reads and writes */
472 	usb_kill_urb(port->write_urb);
473 	usb_kill_urb(port->read_urb);
474 	/* unlink our write pool */
475 	/* FIXME */
476 	/* wgg - do I need this? I think so. */
477 	usb_kill_urb(port->interrupt_in_urb);
478 	info("kl5kusb105 port stats: %ld bytes in, %ld bytes out",
479 					priv->bytes_in, priv->bytes_out);
480 } /* klsi_105_close */
481 
482 
483 /* We need to write a complete 64-byte data block and encode the
484  * number actually sent in the first double-byte, LSB-order. That
485  * leaves at most 62 bytes of payload.
486  */
487 #define KLSI_105_DATA_OFFSET	2   /* in the bulk urb data block */
488 
489 
490 static int klsi_105_write(struct tty_struct *tty,
491 	struct usb_serial_port *port, const unsigned char *buf, int count)
492 {
493 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
494 	int result, size;
495 	int bytes_sent = 0;
496 
497 	dbg("%s - port %d", __func__, port->number);
498 
499 	while (count > 0) {
500 		/* try to find a free urb (write 0 bytes if none) */
501 		struct urb *urb = NULL;
502 		unsigned long flags;
503 		int i;
504 		/* since the pool is per-port we might not need
505 		   the spin lock !? */
506 		spin_lock_irqsave(&priv->lock, flags);
507 		for (i = 0; i < NUM_URBS; i++) {
508 			if (priv->write_urb_pool[i]->status != -EINPROGRESS) {
509 				urb = priv->write_urb_pool[i];
510 				dbg("%s - using pool URB %d", __func__, i);
511 				break;
512 			}
513 		}
514 		spin_unlock_irqrestore(&priv->lock, flags);
515 
516 		if (urb == NULL) {
517 			dbg("%s - no more free urbs", __func__);
518 			goto exit;
519 		}
520 
521 		if (urb->transfer_buffer == NULL) {
522 			urb->transfer_buffer =
523 				kmalloc(URB_TRANSFER_BUFFER_SIZE, GFP_ATOMIC);
524 			if (urb->transfer_buffer == NULL) {
525 				err("%s - no more kernel memory...", __func__);
526 				goto exit;
527 			}
528 		}
529 
530 		size = min(count, port->bulk_out_size - KLSI_105_DATA_OFFSET);
531 		size = min(size, URB_TRANSFER_BUFFER_SIZE -
532 							KLSI_105_DATA_OFFSET);
533 
534 		memcpy(urb->transfer_buffer + KLSI_105_DATA_OFFSET, buf, size);
535 
536 		/* write payload size into transfer buffer */
537 		((__u8 *)urb->transfer_buffer)[0] = (__u8) (size & 0xFF);
538 		((__u8 *)urb->transfer_buffer)[1] = (__u8) ((size & 0xFF00)>>8);
539 
540 		/* set up our urb */
541 		usb_fill_bulk_urb(urb, port->serial->dev,
542 			      usb_sndbulkpipe(port->serial->dev,
543 					      port->bulk_out_endpointAddress),
544 			      urb->transfer_buffer,
545 			      URB_TRANSFER_BUFFER_SIZE,
546 			      klsi_105_write_bulk_callback,
547 			      port);
548 
549 		/* send the data out the bulk port */
550 		result = usb_submit_urb(urb, GFP_ATOMIC);
551 		if (result) {
552 			err("%s - failed submitting write urb, error %d",
553 							__func__, result);
554 			goto exit;
555 		}
556 		buf += size;
557 		bytes_sent += size;
558 		count -= size;
559 	}
560 exit:
561 	/* lockless, but it's for debug info only... */
562 	priv->bytes_out += bytes_sent;
563 
564 	return bytes_sent;	/* that's how much we wrote */
565 } /* klsi_105_write */
566 
567 static void klsi_105_write_bulk_callback(struct urb *urb)
568 {
569 	struct usb_serial_port *port = urb->context;
570 	int status = urb->status;
571 
572 	dbg("%s - port %d", __func__, port->number);
573 
574 	if (status) {
575 		dbg("%s - nonzero write bulk status received: %d", __func__,
576 		    status);
577 		return;
578 	}
579 
580 	usb_serial_port_softint(port);
581 } /* klsi_105_write_bulk_completion_callback */
582 
583 
584 /* return number of characters currently in the writing process */
585 static int klsi_105_chars_in_buffer(struct tty_struct *tty)
586 {
587 	struct usb_serial_port *port = tty->driver_data;
588 	int chars = 0;
589 	int i;
590 	unsigned long flags;
591 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
592 
593 	spin_lock_irqsave(&priv->lock, flags);
594 
595 	for (i = 0; i < NUM_URBS; ++i) {
596 		if (priv->write_urb_pool[i]->status == -EINPROGRESS)
597 			chars += URB_TRANSFER_BUFFER_SIZE;
598 	}
599 
600 	spin_unlock_irqrestore(&priv->lock, flags);
601 
602 	dbg("%s - returns %d", __func__, chars);
603 	return chars;
604 }
605 
606 static int klsi_105_write_room(struct tty_struct *tty)
607 {
608 	struct usb_serial_port *port = tty->driver_data;
609 	unsigned long flags;
610 	int i;
611 	int room = 0;
612 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
613 
614 	spin_lock_irqsave(&priv->lock, flags);
615 	for (i = 0; i < NUM_URBS; ++i) {
616 		if (priv->write_urb_pool[i]->status != -EINPROGRESS)
617 			room += URB_TRANSFER_BUFFER_SIZE;
618 	}
619 
620 	spin_unlock_irqrestore(&priv->lock, flags);
621 
622 	dbg("%s - returns %d", __func__, room);
623 	return room;
624 }
625 
626 
627 
628 static void klsi_105_read_bulk_callback(struct urb *urb)
629 {
630 	struct usb_serial_port *port = urb->context;
631 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
632 	struct tty_struct *tty;
633 	unsigned char *data = urb->transfer_buffer;
634 	int rc;
635 	int status = urb->status;
636 
637 	dbg("%s - port %d", __func__, port->number);
638 
639 	/* The urb might have been killed. */
640 	if (status) {
641 		dbg("%s - nonzero read bulk status received: %d", __func__,
642 		    status);
643 		return;
644 	}
645 
646 	/* The data received is again preceded by a length double-byte in LSB-
647 	 * first order (see klsi_105_write() )
648 	 */
649 	if (urb->actual_length == 0) {
650 		/* empty urbs seem to happen, we ignore them */
651 		/* dbg("%s - emtpy URB", __func__); */
652 	       ;
653 	} else if (urb->actual_length <= 2) {
654 		dbg("%s - size %d URB not understood", __func__,
655 		    urb->actual_length);
656 		usb_serial_debug_data(debug, &port->dev, __func__,
657 				      urb->actual_length, data);
658 	} else {
659 		int bytes_sent = ((__u8 *) data)[0] +
660 				 ((unsigned int) ((__u8 *) data)[1] << 8);
661 		tty = port->port.tty;
662 		/* we should immediately resubmit the URB, before attempting
663 		 * to pass the data on to the tty layer. But that needs locking
664 		 * against re-entry an then mixed-up data because of
665 		 * intermixed tty_flip_buffer_push()s
666 		 * FIXME
667 		 */
668 		usb_serial_debug_data(debug, &port->dev, __func__,
669 				      urb->actual_length, data);
670 
671 		if (bytes_sent + 2 > urb->actual_length) {
672 			dbg("%s - trying to read more data than available"
673 			    " (%d vs. %d)", __func__,
674 			    bytes_sent+2, urb->actual_length);
675 			/* cap at implied limit */
676 			bytes_sent = urb->actual_length - 2;
677 		}
678 
679 		tty_buffer_request_room(tty, bytes_sent);
680 		tty_insert_flip_string(tty, data + 2, bytes_sent);
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",
697 							__func__, rc);
698 } /* klsi_105_read_bulk_callback */
699 
700 
701 static void klsi_105_set_termios(struct tty_struct *tty,
702 				 struct usb_serial_port *port,
703 				 struct ktermios *old_termios)
704 {
705 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
706 	unsigned int iflag = tty->termios->c_iflag;
707 	unsigned int old_iflag = old_termios->c_iflag;
708 	unsigned int cflag = tty->termios->c_cflag;
709 	unsigned int old_cflag = old_termios->c_cflag;
710 	struct klsi_105_port_settings cfg;
711 	unsigned long flags;
712 	speed_t baud;
713 
714 	/* lock while we are modifying the settings */
715 	spin_lock_irqsave(&priv->lock, flags);
716 
717 	/*
718 	 * Update baud rate
719 	 */
720 	baud = tty_get_baud_rate(tty);
721 
722 	if ((cflag & CBAUD) != (old_cflag & CBAUD)) {
723 		/* reassert DTR and (maybe) RTS on transition from B0 */
724 		if ((old_cflag & CBAUD) == B0) {
725 			dbg("%s: baud was B0", __func__);
726 #if 0
727 			priv->control_state |= TIOCM_DTR;
728 			/* don't set RTS if using hardware flow control */
729 			if (!(old_cflag & CRTSCTS))
730 				priv->control_state |= TIOCM_RTS;
731 			mct_u232_set_modem_ctrl(serial, priv->control_state);
732 #endif
733 		}
734 	}
735 	switch (baud) {
736 	case 0: /* handled below */
737 		break;
738 	case 1200:
739 		priv->cfg.baudrate = kl5kusb105a_sio_b1200;
740 		break;
741 	case 2400:
742 		priv->cfg.baudrate = kl5kusb105a_sio_b2400;
743 		break;
744 	case 4800:
745 		priv->cfg.baudrate = kl5kusb105a_sio_b4800;
746 		break;
747 	case 9600:
748 		priv->cfg.baudrate = kl5kusb105a_sio_b9600;
749 		break;
750 	case 19200:
751 		priv->cfg.baudrate = kl5kusb105a_sio_b19200;
752 		break;
753 	case 38400:
754 		priv->cfg.baudrate = kl5kusb105a_sio_b38400;
755 		break;
756 	case 57600:
757 		priv->cfg.baudrate = kl5kusb105a_sio_b57600;
758 		break;
759 	case 115200:
760 		priv->cfg.baudrate = kl5kusb105a_sio_b115200;
761 		break;
762 	default:
763 		dbg("KLSI USB->Serial converter:"
764 		    " unsupported baudrate request, using default of 9600");
765 			priv->cfg.baudrate = kl5kusb105a_sio_b9600;
766 		baud = 9600;
767 		break;
768 	}
769 	if ((cflag & CBAUD) == B0) {
770 		dbg("%s: baud is B0", __func__);
771 		/* Drop RTS and DTR */
772 		/* maybe this should be simulated by sending read
773 		 * disable and read enable messages?
774 		 */
775 		;
776 #if 0
777 		priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
778 		mct_u232_set_modem_ctrl(serial, priv->control_state);
779 #endif
780 	}
781 	tty_encode_baud_rate(tty, baud, baud);
782 
783 	if ((cflag & CSIZE) != (old_cflag & CSIZE)) {
784 		/* set the number of data bits */
785 		switch (cflag & CSIZE) {
786 		case CS5:
787 			dbg("%s - 5 bits/byte not supported", __func__);
788 			spin_unlock_irqrestore(&priv->lock, flags);
789 			return ;
790 		case CS6:
791 			dbg("%s - 6 bits/byte not supported", __func__);
792 			spin_unlock_irqrestore(&priv->lock, flags);
793 			return ;
794 		case CS7:
795 			priv->cfg.databits = kl5kusb105a_dtb_7;
796 			break;
797 		case CS8:
798 			priv->cfg.databits = kl5kusb105a_dtb_8;
799 			break;
800 		default:
801 			err("CSIZE was not CS5-CS8, using default of 8");
802 			priv->cfg.databits = kl5kusb105a_dtb_8;
803 			break;
804 		}
805 	}
806 
807 	/*
808 	 * Update line control register (LCR)
809 	 */
810 	if ((cflag & (PARENB|PARODD)) != (old_cflag & (PARENB|PARODD))
811 	    || (cflag & CSTOPB) != (old_cflag & CSTOPB)) {
812 		/* Not currently supported */
813 		tty->termios->c_cflag &= ~(PARENB|PARODD|CSTOPB);
814 #if 0
815 		priv->last_lcr = 0;
816 
817 		/* set the parity */
818 		if (cflag & PARENB)
819 			priv->last_lcr |= (cflag & PARODD) ?
820 				MCT_U232_PARITY_ODD : MCT_U232_PARITY_EVEN;
821 		else
822 			priv->last_lcr |= MCT_U232_PARITY_NONE;
823 
824 		/* set the number of stop bits */
825 		priv->last_lcr |= (cflag & CSTOPB) ?
826 			MCT_U232_STOP_BITS_2 : MCT_U232_STOP_BITS_1;
827 
828 		mct_u232_set_line_ctrl(serial, priv->last_lcr);
829 #endif
830 		;
831 	}
832 	/*
833 	 * Set flow control: well, I do not really now how to handle DTR/RTS.
834 	 * Just do what we have seen with SniffUSB on Win98.
835 	 */
836 	if ((iflag & IXOFF) != (old_iflag & IXOFF)
837 	    || (iflag & IXON) != (old_iflag & IXON)
838 	    ||  (cflag & CRTSCTS) != (old_cflag & CRTSCTS)) {
839 		/* Not currently supported */
840 		tty->termios->c_cflag &= ~CRTSCTS;
841 		/* Drop DTR/RTS if no flow control otherwise assert */
842 #if 0
843 		if ((iflag & IXOFF) || (iflag & IXON) || (cflag & CRTSCTS))
844 			priv->control_state |= TIOCM_DTR | TIOCM_RTS;
845 		else
846 			priv->control_state &= ~(TIOCM_DTR | TIOCM_RTS);
847 		mct_u232_set_modem_ctrl(serial, priv->control_state);
848 #endif
849 		;
850 	}
851 	memcpy(&cfg, &priv->cfg, sizeof(cfg));
852 	spin_unlock_irqrestore(&priv->lock, flags);
853 
854 	/* now commit changes to device */
855 	klsi_105_chg_port_settings(port, &cfg);
856 } /* klsi_105_set_termios */
857 
858 
859 #if 0
860 static void mct_u232_break_ctl(struct tty_struct *tty, int break_state)
861 {
862 	struct usb_serial_port *port = tty->driver_data;
863 	struct usb_serial *serial = port->serial;
864 	struct mct_u232_private *priv =
865 				(struct mct_u232_private *)port->private;
866 	unsigned char lcr = priv->last_lcr;
867 
868 	dbg("%sstate=%d", __func__, break_state);
869 
870 	if (break_state)
871 		lcr |= MCT_U232_SET_BREAK;
872 
873 	mct_u232_set_line_ctrl(serial, lcr);
874 } /* mct_u232_break_ctl */
875 #endif
876 
877 static int klsi_105_tiocmget(struct tty_struct *tty, struct file *file)
878 {
879 	struct usb_serial_port *port = tty->driver_data;
880 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
881 	unsigned long flags;
882 	int rc;
883 	unsigned long line_state;
884 	dbg("%s - request, just guessing", __func__);
885 
886 	rc = klsi_105_get_line_state(port, &line_state);
887 	if (rc < 0) {
888 		err("Reading line control failed (error = %d)", rc);
889 		/* better return value? EAGAIN? */
890 		return rc;
891 	}
892 
893 	spin_lock_irqsave(&priv->lock, flags);
894 	priv->line_state = line_state;
895 	spin_unlock_irqrestore(&priv->lock, flags);
896 	dbg("%s - read line state 0x%lx", __func__, line_state);
897 	return (int)line_state;
898 }
899 
900 static int klsi_105_tiocmset(struct tty_struct *tty, struct file *file,
901 			     unsigned int set, unsigned int clear)
902 {
903 	int retval = -EINVAL;
904 
905 	dbg("%s", __func__);
906 
907 /* if this ever gets implemented, it should be done something like this:
908 	struct usb_serial *serial = port->serial;
909 	struct klsi_105_private *priv = usb_get_serial_port_data(port);
910 	unsigned long flags;
911 	int control;
912 
913 	spin_lock_irqsave (&priv->lock, flags);
914 	if (set & TIOCM_RTS)
915 		priv->control_state |= TIOCM_RTS;
916 	if (set & TIOCM_DTR)
917 		priv->control_state |= TIOCM_DTR;
918 	if (clear & TIOCM_RTS)
919 		priv->control_state &= ~TIOCM_RTS;
920 	if (clear & TIOCM_DTR)
921 		priv->control_state &= ~TIOCM_DTR;
922 	control = priv->control_state;
923 	spin_unlock_irqrestore (&priv->lock, flags);
924 	retval = mct_u232_set_modem_ctrl(serial, control);
925 */
926 	return retval;
927 }
928 
929 static void klsi_105_throttle(struct tty_struct *tty)
930 {
931 	struct usb_serial_port *port = tty->driver_data;
932 	dbg("%s - port %d", __func__, port->number);
933 	usb_kill_urb(port->read_urb);
934 }
935 
936 static void klsi_105_unthrottle(struct tty_struct *tty)
937 {
938 	struct usb_serial_port *port = tty->driver_data;
939 	int result;
940 
941 	dbg("%s - port %d", __func__, port->number);
942 
943 	port->read_urb->dev = port->serial->dev;
944 	result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
945 	if (result)
946 		err("%s - failed submitting read urb, error %d", __func__,
947 		    result);
948 }
949 
950 
951 
952 static int __init klsi_105_init(void)
953 {
954 	int retval;
955 	retval = usb_serial_register(&kl5kusb105d_device);
956 	if (retval)
957 		goto failed_usb_serial_register;
958 	retval = usb_register(&kl5kusb105d_driver);
959 	if (retval)
960 		goto failed_usb_register;
961 
962 	info(DRIVER_DESC " " DRIVER_VERSION);
963 	return 0;
964 failed_usb_register:
965 	usb_serial_deregister(&kl5kusb105d_device);
966 failed_usb_serial_register:
967 	return retval;
968 }
969 
970 
971 static void __exit klsi_105_exit(void)
972 {
973 	usb_deregister(&kl5kusb105d_driver);
974 	usb_serial_deregister(&kl5kusb105d_device);
975 }
976 
977 
978 module_init(klsi_105_init);
979 module_exit(klsi_105_exit);
980 
981 MODULE_AUTHOR(DRIVER_AUTHOR);
982 MODULE_DESCRIPTION(DRIVER_DESC);
983 MODULE_LICENSE("GPL");
984 
985 
986 module_param(debug, bool, S_IRUGO | S_IWUSR);
987 MODULE_PARM_DESC(debug, "enable extensive debugging messages");
988 
989 /* vim: set sts=8 ts=8 sw=8: */
990