xref: /openbmc/linux/drivers/usb/serial/keyspan_pda.c (revision 64c70b1c)
1 /*
2  * USB Keyspan PDA / Xircom / Entregra Converter driver
3  *
4  * Copyright (C) 1999 - 2001 Greg Kroah-Hartman	<greg@kroah.com>
5  * Copyright (C) 1999, 2000 Brian Warner	<warner@lothar.com>
6  * Copyright (C) 2000 Al Borchers		<borchers@steinerpoint.com>
7  *
8  *	This program is free software; you can redistribute it and/or modify
9  *	it under the terms of the GNU General Public License as published by
10  *	the Free Software Foundation; either version 2 of the License, or
11  *	(at your option) any later version.
12  *
13  * See Documentation/usb/usb-serial.txt for more information on using this driver
14  *
15  * (09/07/2001) gkh
16  *	cleaned up the Xircom support.  Added ids for Entregra device which is
17  *	the same as the Xircom device.  Enabled the code to be compiled for
18  *	either Xircom or Keyspan devices.
19  *
20  * (08/11/2001) Cristian M. Craciunescu
21  *	support for Xircom PGSDB9
22  *
23  * (05/31/2001) gkh
24  *	switched from using spinlock to a semaphore, which fixes lots of problems.
25  *
26  * (04/08/2001) gb
27  *	Identify version on module load.
28  *
29  * (11/01/2000) Adam J. Richter
30  *	usb_device_id table support
31  *
32  * (10/05/2000) gkh
33  *	Fixed bug with urb->dev not being set properly, now that the usb
34  *	core needs it.
35  *
36  * (08/28/2000) gkh
37  *	Added locks for SMP safeness.
38  *	Fixed MOD_INC and MOD_DEC logic and the ability to open a port more
39  *	than once.
40  *
41  * (07/20/2000) borchers
42  *	- keyspan_pda_write no longer sleeps if it is called on interrupt time;
43  *	  PPP and the line discipline with stty echo on can call write on
44  *	  interrupt time and this would cause an oops if write slept
45  *	- if keyspan_pda_write is in an interrupt, it will not call
46  *	  usb_control_msg (which sleeps) to query the room in the device
47  *	  buffer, it simply uses the current room value it has
48  *	- if the urb is busy or if it is throttled keyspan_pda_write just
49  *	  returns 0, rather than sleeping to wait for this to change; the
50  *	  write_chan code in n_tty.c will sleep if needed before calling
51  *	  keyspan_pda_write again
52  *	- if the device needs to be unthrottled, write now queues up the
53  *	  call to usb_control_msg (which sleeps) to unthrottle the device
54  *	- the wakeups from keyspan_pda_write_bulk_callback are queued rather
55  *	  than done directly from the callback to avoid the race in write_chan
56  *	- keyspan_pda_chars_in_buffer also indicates its buffer is full if the
57  *	  urb status is -EINPROGRESS, meaning it cannot write at the moment
58  *
59  * (07/19/2000) gkh
60  *	Added module_init and module_exit functions to handle the fact that this
61  *	driver is a loadable module now.
62  *
63  * (03/26/2000) gkh
64  *	Split driver up into device specific pieces.
65  *
66  */
67 
68 
69 #include <linux/kernel.h>
70 #include <linux/errno.h>
71 #include <linux/init.h>
72 #include <linux/slab.h>
73 #include <linux/tty.h>
74 #include <linux/tty_driver.h>
75 #include <linux/tty_flip.h>
76 #include <linux/module.h>
77 #include <linux/spinlock.h>
78 #include <linux/workqueue.h>
79 #include <asm/uaccess.h>
80 #include <linux/usb.h>
81 #include <linux/usb/serial.h>
82 
83 static int debug;
84 
85 struct ezusb_hex_record {
86 	__u16 address;
87 	__u8 data_size;
88 	__u8 data[16];
89 };
90 
91 /* make a simple define to handle if we are compiling keyspan_pda or xircom support */
92 #if defined(CONFIG_USB_SERIAL_KEYSPAN_PDA) || defined(CONFIG_USB_SERIAL_KEYSPAN_PDA_MODULE)
93 	#define KEYSPAN
94 #else
95 	#undef KEYSPAN
96 #endif
97 #if defined(CONFIG_USB_SERIAL_XIRCOM) || defined(CONFIG_USB_SERIAL_XIRCOM_MODULE)
98 	#define XIRCOM
99 #else
100 	#undef XIRCOM
101 #endif
102 
103 #ifdef KEYSPAN
104 #include "keyspan_pda_fw.h"
105 #endif
106 
107 #ifdef XIRCOM
108 #include "xircom_pgs_fw.h"
109 #endif
110 
111 /*
112  * Version Information
113  */
114 #define DRIVER_VERSION "v1.1"
115 #define DRIVER_AUTHOR "Brian Warner <warner@lothar.com>"
116 #define DRIVER_DESC "USB Keyspan PDA Converter driver"
117 
118 struct keyspan_pda_private {
119 	int			tx_room;
120 	int			tx_throttled;
121 	struct work_struct			wakeup_work;
122 	struct work_struct			unthrottle_work;
123 	struct usb_serial	*serial;
124 	struct usb_serial_port	*port;
125 };
126 
127 
128 #define KEYSPAN_VENDOR_ID		0x06cd
129 #define KEYSPAN_PDA_FAKE_ID		0x0103
130 #define KEYSPAN_PDA_ID			0x0104 /* no clue */
131 
132 /* For Xircom PGSDB9 and older Entregra version of the same device */
133 #define XIRCOM_VENDOR_ID		0x085a
134 #define XIRCOM_FAKE_ID			0x8027
135 #define ENTREGRA_VENDOR_ID		0x1645
136 #define ENTREGRA_FAKE_ID		0x8093
137 
138 static struct usb_device_id id_table_combined [] = {
139 #ifdef KEYSPAN
140 	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_FAKE_ID) },
141 #endif
142 #ifdef XIRCOM
143 	{ USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID) },
144 	{ USB_DEVICE(ENTREGRA_VENDOR_ID, ENTREGRA_FAKE_ID) },
145 #endif
146 	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_ID) },
147 	{ }						/* Terminating entry */
148 };
149 
150 MODULE_DEVICE_TABLE (usb, id_table_combined);
151 
152 static struct usb_driver keyspan_pda_driver = {
153 	.name =		"keyspan_pda",
154 	.probe =	usb_serial_probe,
155 	.disconnect =	usb_serial_disconnect,
156 	.id_table =	id_table_combined,
157 	.no_dynamic_id = 	1,
158 };
159 
160 static struct usb_device_id id_table_std [] = {
161 	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_ID) },
162 	{ }						/* Terminating entry */
163 };
164 
165 #ifdef KEYSPAN
166 static struct usb_device_id id_table_fake [] = {
167 	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_FAKE_ID) },
168 	{ }						/* Terminating entry */
169 };
170 #endif
171 
172 #ifdef XIRCOM
173 static struct usb_device_id id_table_fake_xircom [] = {
174         { USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID) },
175         { USB_DEVICE(ENTREGRA_VENDOR_ID, ENTREGRA_FAKE_ID) },
176         { }
177 };
178 #endif
179 
180 static void keyspan_pda_wakeup_write(struct work_struct *work)
181 {
182 	struct keyspan_pda_private *priv =
183 		container_of(work, struct keyspan_pda_private, wakeup_work);
184 	struct usb_serial_port *port = priv->port;
185 
186 	tty_wakeup(port->tty);
187 }
188 
189 static void keyspan_pda_request_unthrottle(struct work_struct *work)
190 {
191 	struct keyspan_pda_private *priv =
192 		container_of(work, struct keyspan_pda_private, unthrottle_work);
193 	struct usb_serial *serial = priv->serial;
194 	int result;
195 
196 	dbg(" request_unthrottle");
197 	/* ask the device to tell us when the tx buffer becomes
198 	   sufficiently empty */
199 	result = usb_control_msg(serial->dev,
200 				 usb_sndctrlpipe(serial->dev, 0),
201 				 7, /* request_unthrottle */
202 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE
203 				 | USB_DIR_OUT,
204 				 16, /* value: threshold */
205 				 0, /* index */
206 				 NULL,
207 				 0,
208 				 2000);
209 	if (result < 0)
210 		dbg("%s - error %d from usb_control_msg",
211 		    __FUNCTION__, result);
212 }
213 
214 
215 static void keyspan_pda_rx_interrupt (struct urb *urb)
216 {
217 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
218        	struct tty_struct *tty = port->tty;
219 	unsigned char *data = urb->transfer_buffer;
220 	int i;
221 	int status;
222 	struct keyspan_pda_private *priv;
223 	priv = usb_get_serial_port_data(port);
224 
225 	switch (urb->status) {
226 	case 0:
227 		/* success */
228 		break;
229 	case -ECONNRESET:
230 	case -ENOENT:
231 	case -ESHUTDOWN:
232 		/* this urb is terminated, clean up */
233 		dbg("%s - urb shutting down with status: %d", __FUNCTION__, urb->status);
234 		return;
235 	default:
236 		dbg("%s - nonzero urb status received: %d", __FUNCTION__, urb->status);
237 		goto exit;
238 	}
239 
240  	/* see if the message is data or a status interrupt */
241 	switch (data[0]) {
242 	case 0:
243 		/* rest of message is rx data */
244 		if (urb->actual_length) {
245 			for (i = 1; i < urb->actual_length ; ++i) {
246 				tty_insert_flip_char(tty, data[i], 0);
247 			}
248 			tty_flip_buffer_push(tty);
249 		}
250 		break;
251 	case 1:
252 		/* status interrupt */
253 		dbg(" rx int, d1=%d, d2=%d", data[1], data[2]);
254 		switch (data[1]) {
255 		case 1: /* modemline change */
256 			break;
257 		case 2: /* tx unthrottle interrupt */
258 			priv->tx_throttled = 0;
259 			/* queue up a wakeup at scheduler time */
260 			schedule_work(&priv->wakeup_work);
261 			break;
262 		default:
263 			break;
264 		}
265 		break;
266 	default:
267 		break;
268 	}
269 
270 exit:
271 	status = usb_submit_urb (urb, GFP_ATOMIC);
272 	if (status)
273 		err ("%s - usb_submit_urb failed with result %d",
274 		     __FUNCTION__, status);
275 }
276 
277 
278 static void keyspan_pda_rx_throttle (struct usb_serial_port *port)
279 {
280 	/* stop receiving characters. We just turn off the URB request, and
281 	   let chars pile up in the device. If we're doing hardware
282 	   flowcontrol, the device will signal the other end when its buffer
283 	   fills up. If we're doing XON/XOFF, this would be a good time to
284 	   send an XOFF, although it might make sense to foist that off
285 	   upon the device too. */
286 
287 	dbg("keyspan_pda_rx_throttle port %d", port->number);
288 	usb_kill_urb(port->interrupt_in_urb);
289 }
290 
291 
292 static void keyspan_pda_rx_unthrottle (struct usb_serial_port *port)
293 {
294 	/* just restart the receive interrupt URB */
295 	dbg("keyspan_pda_rx_unthrottle port %d", port->number);
296 	port->interrupt_in_urb->dev = port->serial->dev;
297 	if (usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC))
298 		dbg(" usb_submit_urb(read urb) failed");
299 	return;
300 }
301 
302 
303 static int keyspan_pda_setbaud (struct usb_serial *serial, int baud)
304 {
305 	int rc;
306 	int bindex;
307 
308 	switch(baud) {
309 		case 110: bindex = 0; break;
310 		case 300: bindex = 1; break;
311 		case 1200: bindex = 2; break;
312 		case 2400: bindex = 3; break;
313 		case 4800: bindex = 4; break;
314 		case 9600: bindex = 5; break;
315 		case 19200: bindex = 6; break;
316 		case 38400: bindex = 7; break;
317 		case 57600: bindex = 8; break;
318 		case 115200: bindex = 9; break;
319 		default: return -EINVAL;
320 	}
321 
322 	/* rather than figure out how to sleep while waiting for this
323 	   to complete, I just use the "legacy" API. */
324 	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
325 			     0, /* set baud */
326 			     USB_TYPE_VENDOR
327 			     | USB_RECIP_INTERFACE
328 			     | USB_DIR_OUT, /* type */
329 			     bindex, /* value */
330 			     0, /* index */
331 			     NULL, /* &data */
332 			     0, /* size */
333 			     2000); /* timeout */
334 	return(rc);
335 }
336 
337 
338 static void keyspan_pda_break_ctl (struct usb_serial_port *port, int break_state)
339 {
340 	struct usb_serial *serial = port->serial;
341 	int value;
342 	int result;
343 
344 	if (break_state == -1)
345 		value = 1; /* start break */
346 	else
347 		value = 0; /* clear break */
348 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
349 				4, /* set break */
350 				USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
351 				value, 0, NULL, 0, 2000);
352 	if (result < 0)
353 		dbg("%s - error %d from usb_control_msg",
354 		    __FUNCTION__, result);
355 	/* there is something funky about this.. the TCSBRK that 'cu' performs
356 	   ought to translate into a break_ctl(-1),break_ctl(0) pair HZ/4
357 	   seconds apart, but it feels like the break sent isn't as long as it
358 	   is on /dev/ttyS0 */
359 }
360 
361 
362 static void keyspan_pda_set_termios (struct usb_serial_port *port,
363 				     struct ktermios *old_termios)
364 {
365 	struct usb_serial *serial = port->serial;
366 	unsigned int cflag = port->tty->termios->c_cflag;
367 
368 	/* cflag specifies lots of stuff: number of stop bits, parity, number
369 	   of data bits, baud. What can the device actually handle?:
370 	   CSTOPB (1 stop bit or 2)
371 	   PARENB (parity)
372 	   CSIZE (5bit .. 8bit)
373 	   There is minimal hw support for parity (a PSW bit seems to hold the
374 	   parity of whatever is in the accumulator). The UART either deals
375 	   with 10 bits (start, 8 data, stop) or 11 bits (start, 8 data,
376 	   1 special, stop). So, with firmware changes, we could do:
377 	   8N1: 10 bit
378 	   8N2: 11 bit, extra bit always (mark?)
379 	   8[EOMS]1: 11 bit, extra bit is parity
380 	   7[EOMS]1: 10 bit, b0/b7 is parity
381 	   7[EOMS]2: 11 bit, b0/b7 is parity, extra bit always (mark?)
382 
383 	   HW flow control is dictated by the tty->termios->c_cflags & CRTSCTS
384 	   bit.
385 
386 	   For now, just do baud. */
387 
388 	switch (cflag & CBAUD) {
389 		/* we could support more values here, just need to calculate
390 		   the necessary divisors in the firmware. <asm/termbits.h>
391 		   has the Bnnn constants. */
392 		case B110: keyspan_pda_setbaud(serial, 110); break;
393 		case B300: keyspan_pda_setbaud(serial, 300); break;
394 		case B1200: keyspan_pda_setbaud(serial, 1200); break;
395 		case B2400: keyspan_pda_setbaud(serial, 2400); break;
396 		case B4800: keyspan_pda_setbaud(serial, 4800); break;
397 		case B9600: keyspan_pda_setbaud(serial, 9600); break;
398 		case B19200: keyspan_pda_setbaud(serial, 19200); break;
399 		case B38400: keyspan_pda_setbaud(serial, 38400); break;
400 		case B57600: keyspan_pda_setbaud(serial, 57600); break;
401 		case B115200: keyspan_pda_setbaud(serial, 115200); break;
402 		default: dbg("can't handle requested baud rate"); break;
403 	}
404 }
405 
406 
407 /* modem control pins: DTR and RTS are outputs and can be controlled.
408    DCD, RI, DSR, CTS are inputs and can be read. All outputs can also be
409    read. The byte passed is: DTR(b7) DCD RI DSR CTS RTS(b2) unused unused */
410 
411 static int keyspan_pda_get_modem_info(struct usb_serial *serial,
412 				      unsigned char *value)
413 {
414 	int rc;
415 	unsigned char data;
416 	rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
417 			     3, /* get pins */
418 			     USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_IN,
419 			     0, 0, &data, 1, 2000);
420 	if (rc > 0)
421 		*value = data;
422 	return rc;
423 }
424 
425 
426 static int keyspan_pda_set_modem_info(struct usb_serial *serial,
427 				      unsigned char value)
428 {
429 	int rc;
430 	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
431 			     3, /* set pins */
432 			     USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_OUT,
433 			     value, 0, NULL, 0, 2000);
434 	return rc;
435 }
436 
437 static int keyspan_pda_tiocmget(struct usb_serial_port *port, struct file *file)
438 {
439 	struct usb_serial *serial = port->serial;
440 	int rc;
441 	unsigned char status;
442 	int value;
443 
444 	rc = keyspan_pda_get_modem_info(serial, &status);
445 	if (rc < 0)
446 		return rc;
447 	value =
448 		((status & (1<<7)) ? TIOCM_DTR : 0) |
449 		((status & (1<<6)) ? TIOCM_CAR : 0) |
450 		((status & (1<<5)) ? TIOCM_RNG : 0) |
451 		((status & (1<<4)) ? TIOCM_DSR : 0) |
452 		((status & (1<<3)) ? TIOCM_CTS : 0) |
453 		((status & (1<<2)) ? TIOCM_RTS : 0);
454 	return value;
455 }
456 
457 static int keyspan_pda_tiocmset(struct usb_serial_port *port, struct file *file,
458 				unsigned int set, unsigned int clear)
459 {
460 	struct usb_serial *serial = port->serial;
461 	int rc;
462 	unsigned char status;
463 
464 	rc = keyspan_pda_get_modem_info(serial, &status);
465 	if (rc < 0)
466 		return rc;
467 
468 	if (set & TIOCM_RTS)
469 		status |= (1<<2);
470 	if (set & TIOCM_DTR)
471 		status |= (1<<7);
472 
473 	if (clear & TIOCM_RTS)
474 		status &= ~(1<<2);
475 	if (clear & TIOCM_DTR)
476 		status &= ~(1<<7);
477 	rc = keyspan_pda_set_modem_info(serial, status);
478 	return rc;
479 }
480 
481 static int keyspan_pda_ioctl(struct usb_serial_port *port, struct file *file,
482 			     unsigned int cmd, unsigned long arg)
483 {
484 	switch (cmd) {
485 	case TIOCMIWAIT:
486 		/* wait for any of the 4 modem inputs (DCD,RI,DSR,CTS)*/
487 		/* TODO */
488 	case TIOCGICOUNT:
489 		/* return count of modemline transitions */
490 		return 0; /* TODO */
491 	}
492 
493 	return -ENOIOCTLCMD;
494 }
495 
496 static int keyspan_pda_write(struct usb_serial_port *port,
497 			     const unsigned char *buf, int count)
498 {
499 	struct usb_serial *serial = port->serial;
500 	int request_unthrottle = 0;
501 	int rc = 0;
502 	struct keyspan_pda_private *priv;
503 
504 	priv = usb_get_serial_port_data(port);
505 	/* guess how much room is left in the device's ring buffer, and if we
506 	   want to send more than that, check first, updating our notion of
507 	   what is left. If our write will result in no room left, ask the
508 	   device to give us an interrupt when the room available rises above
509 	   a threshold, and hold off all writers (eventually, those using
510 	   select() or poll() too) until we receive that unthrottle interrupt.
511 	   Block if we can't write anything at all, otherwise write as much as
512 	   we can. */
513 	dbg("keyspan_pda_write(%d)",count);
514 	if (count == 0) {
515 		dbg(" write request of 0 bytes");
516 		return (0);
517 	}
518 
519 	/* we might block because of:
520 	   the TX urb is in-flight (wait until it completes)
521 	   the device is full (wait until it says there is room)
522 	*/
523 	spin_lock_bh(&port->lock);
524 	if (port->write_urb_busy || priv->tx_throttled) {
525 		spin_unlock_bh(&port->lock);
526 		return 0;
527 	}
528 	port->write_urb_busy = 1;
529 	spin_unlock_bh(&port->lock);
530 
531 	/* At this point the URB is in our control, nobody else can submit it
532 	   again (the only sudden transition was the one from EINPROGRESS to
533 	   finished).  Also, the tx process is not throttled. So we are
534 	   ready to write. */
535 
536 	count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
537 
538 	/* Check if we might overrun the Tx buffer.   If so, ask the
539 	   device how much room it really has.  This is done only on
540 	   scheduler time, since usb_control_msg() sleeps. */
541 	if (count > priv->tx_room && !in_interrupt()) {
542 		unsigned char room;
543 		rc = usb_control_msg(serial->dev,
544 				     usb_rcvctrlpipe(serial->dev, 0),
545 				     6, /* write_room */
546 				     USB_TYPE_VENDOR | USB_RECIP_INTERFACE
547 				     | USB_DIR_IN,
548 				     0, /* value: 0 means "remaining room" */
549 				     0, /* index */
550 				     &room,
551 				     1,
552 				     2000);
553 		if (rc < 0) {
554 			dbg(" roomquery failed");
555 			goto exit;
556 		}
557 		if (rc == 0) {
558 			dbg(" roomquery returned 0 bytes");
559 			rc = -EIO; /* device didn't return any data */
560 			goto exit;
561 		}
562 		dbg(" roomquery says %d", room);
563 		priv->tx_room = room;
564 	}
565 	if (count > priv->tx_room) {
566 		/* we're about to completely fill the Tx buffer, so
567 		   we'll be throttled afterwards. */
568 		count = priv->tx_room;
569 		request_unthrottle = 1;
570 	}
571 
572 	if (count) {
573 		/* now transfer data */
574 		memcpy (port->write_urb->transfer_buffer, buf, count);
575 		/* send the data out the bulk port */
576 		port->write_urb->transfer_buffer_length = count;
577 
578 		priv->tx_room -= count;
579 
580 		port->write_urb->dev = port->serial->dev;
581 		rc = usb_submit_urb(port->write_urb, GFP_ATOMIC);
582 		if (rc) {
583 			dbg(" usb_submit_urb(write bulk) failed");
584 			goto exit;
585 		}
586 	}
587 	else {
588 		/* There wasn't any room left, so we are throttled until
589 		   the buffer empties a bit */
590 		request_unthrottle = 1;
591 	}
592 
593 	if (request_unthrottle) {
594 		priv->tx_throttled = 1; /* block writers */
595 		schedule_work(&priv->unthrottle_work);
596 	}
597 
598 	rc = count;
599 exit:
600 	if (rc < 0)
601 		port->write_urb_busy = 0;
602 	return rc;
603 }
604 
605 
606 static void keyspan_pda_write_bulk_callback (struct urb *urb)
607 {
608 	struct usb_serial_port *port = (struct usb_serial_port *)urb->context;
609 	struct keyspan_pda_private *priv;
610 
611 	port->write_urb_busy = 0;
612 	priv = usb_get_serial_port_data(port);
613 
614 	/* queue up a wakeup at scheduler time */
615 	schedule_work(&priv->wakeup_work);
616 }
617 
618 
619 static int keyspan_pda_write_room (struct usb_serial_port *port)
620 {
621 	struct keyspan_pda_private *priv;
622 
623 	priv = usb_get_serial_port_data(port);
624 
625 	/* used by n_tty.c for processing of tabs and such. Giving it our
626 	   conservative guess is probably good enough, but needs testing by
627 	   running a console through the device. */
628 
629 	return (priv->tx_room);
630 }
631 
632 
633 static int keyspan_pda_chars_in_buffer (struct usb_serial_port *port)
634 {
635 	struct keyspan_pda_private *priv;
636 
637 	priv = usb_get_serial_port_data(port);
638 
639 	/* when throttled, return at least WAKEUP_CHARS to tell select() (via
640 	   n_tty.c:normal_poll() ) that we're not writeable. */
641 	if (port->write_urb_busy || priv->tx_throttled)
642 		return 256;
643 	return 0;
644 }
645 
646 
647 static int keyspan_pda_open (struct usb_serial_port *port, struct file *filp)
648 {
649 	struct usb_serial *serial = port->serial;
650 	unsigned char room;
651 	int rc = 0;
652 	struct keyspan_pda_private *priv;
653 
654 	/* find out how much room is in the Tx ring */
655 	rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
656 			     6, /* write_room */
657 			     USB_TYPE_VENDOR | USB_RECIP_INTERFACE
658 			     | USB_DIR_IN,
659 			     0, /* value */
660 			     0, /* index */
661 			     &room,
662 			     1,
663 			     2000);
664 	if (rc < 0) {
665 		dbg("%s - roomquery failed", __FUNCTION__);
666 		goto error;
667 	}
668 	if (rc == 0) {
669 		dbg("%s - roomquery returned 0 bytes", __FUNCTION__);
670 		rc = -EIO;
671 		goto error;
672 	}
673 	priv = usb_get_serial_port_data(port);
674 	priv->tx_room = room;
675 	priv->tx_throttled = room ? 0 : 1;
676 
677 	/* the normal serial device seems to always turn on DTR and RTS here,
678 	   so do the same */
679 	if (port->tty->termios->c_cflag & CBAUD)
680 		keyspan_pda_set_modem_info(serial, (1<<7) | (1<<2) );
681 	else
682 		keyspan_pda_set_modem_info(serial, 0);
683 
684 	/*Start reading from the device*/
685 	port->interrupt_in_urb->dev = serial->dev;
686 	rc = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
687 	if (rc) {
688 		dbg("%s - usb_submit_urb(read int) failed", __FUNCTION__);
689 		goto error;
690 	}
691 
692 error:
693 	return rc;
694 }
695 
696 
697 static void keyspan_pda_close(struct usb_serial_port *port, struct file *filp)
698 {
699 	struct usb_serial *serial = port->serial;
700 
701 	if (serial->dev) {
702 		/* the normal serial device seems to always shut off DTR and RTS now */
703 		if (port->tty->termios->c_cflag & HUPCL)
704 			keyspan_pda_set_modem_info(serial, 0);
705 
706 		/* shutdown our bulk reads and writes */
707 		usb_kill_urb(port->write_urb);
708 		usb_kill_urb(port->interrupt_in_urb);
709 	}
710 }
711 
712 
713 /* download the firmware to a "fake" device (pre-renumeration) */
714 static int keyspan_pda_fake_startup (struct usb_serial *serial)
715 {
716 	int response;
717 	const struct ezusb_hex_record *record = NULL;
718 
719 	/* download the firmware here ... */
720 	response = ezusb_set_reset(serial, 1);
721 
722 #ifdef KEYSPAN
723 	if (le16_to_cpu(serial->dev->descriptor.idVendor) == KEYSPAN_VENDOR_ID)
724 		record = &keyspan_pda_firmware[0];
725 #endif
726 #ifdef XIRCOM
727 	if ((le16_to_cpu(serial->dev->descriptor.idVendor) == XIRCOM_VENDOR_ID) ||
728 	    (le16_to_cpu(serial->dev->descriptor.idVendor) == ENTREGRA_VENDOR_ID))
729 		record = &xircom_pgs_firmware[0];
730 #endif
731 	if (record == NULL) {
732 		err("%s: unknown vendor, aborting.", __FUNCTION__);
733 		return -ENODEV;
734 	}
735 
736 	while(record->address != 0xffff) {
737 		response = ezusb_writememory(serial, record->address,
738 					     (unsigned char *)record->data,
739 					     record->data_size, 0xa0);
740 		if (response < 0) {
741 			err("ezusb_writememory failed for Keyspan PDA "
742 			    "firmware (%d %04X %p %d)",
743 			    response,
744 			    record->address, record->data, record->data_size);
745 			break;
746 		}
747 		record++;
748 	}
749 	/* bring device out of reset. Renumeration will occur in a moment
750 	   and the new device will bind to the real driver */
751 	response = ezusb_set_reset(serial, 0);
752 
753 	/* we want this device to fail to have a driver assigned to it. */
754 	return (1);
755 }
756 
757 static int keyspan_pda_startup (struct usb_serial *serial)
758 {
759 
760 	struct keyspan_pda_private *priv;
761 
762 	/* allocate the private data structures for all ports. Well, for all
763 	   one ports. */
764 
765 	priv = kmalloc(sizeof(struct keyspan_pda_private), GFP_KERNEL);
766 	if (!priv)
767 		return (1); /* error */
768 	usb_set_serial_port_data(serial->port[0], priv);
769 	init_waitqueue_head(&serial->port[0]->write_wait);
770 	INIT_WORK(&priv->wakeup_work, keyspan_pda_wakeup_write);
771 	INIT_WORK(&priv->unthrottle_work, keyspan_pda_request_unthrottle);
772 	priv->serial = serial;
773 	priv->port = serial->port[0];
774 	return (0);
775 }
776 
777 static void keyspan_pda_shutdown (struct usb_serial *serial)
778 {
779 	dbg("%s", __FUNCTION__);
780 
781 	kfree(usb_get_serial_port_data(serial->port[0]));
782 }
783 
784 #ifdef KEYSPAN
785 static struct usb_serial_driver keyspan_pda_fake_device = {
786 	.driver = {
787 		.owner =	THIS_MODULE,
788 		.name =		"keyspan_pda_pre",
789 	},
790 	.description =		"Keyspan PDA - (prerenumeration)",
791 	.usb_driver = 		&keyspan_pda_driver,
792 	.id_table =		id_table_fake,
793 	.num_interrupt_in =	NUM_DONT_CARE,
794 	.num_bulk_in =		NUM_DONT_CARE,
795 	.num_bulk_out =		NUM_DONT_CARE,
796 	.num_ports =		1,
797 	.attach =		keyspan_pda_fake_startup,
798 };
799 #endif
800 
801 #ifdef XIRCOM
802 static struct usb_serial_driver xircom_pgs_fake_device = {
803 	.driver = {
804 		.owner =	THIS_MODULE,
805 		.name =		"xircom_no_firm",
806 	},
807 	.description =		"Xircom / Entregra PGS - (prerenumeration)",
808 	.usb_driver = 		&keyspan_pda_driver,
809 	.id_table =		id_table_fake_xircom,
810 	.num_interrupt_in =	NUM_DONT_CARE,
811 	.num_bulk_in =		NUM_DONT_CARE,
812 	.num_bulk_out =		NUM_DONT_CARE,
813 	.num_ports =		1,
814 	.attach =		keyspan_pda_fake_startup,
815 };
816 #endif
817 
818 static struct usb_serial_driver keyspan_pda_device = {
819 	.driver = {
820 		.owner =	THIS_MODULE,
821 		.name =		"keyspan_pda",
822 	},
823 	.description =		"Keyspan PDA",
824 	.usb_driver = 		&keyspan_pda_driver,
825 	.id_table =		id_table_std,
826 	.num_interrupt_in =	1,
827 	.num_bulk_in =		0,
828 	.num_bulk_out =		1,
829 	.num_ports =		1,
830 	.open =			keyspan_pda_open,
831 	.close =		keyspan_pda_close,
832 	.write =		keyspan_pda_write,
833 	.write_room =		keyspan_pda_write_room,
834 	.write_bulk_callback = 	keyspan_pda_write_bulk_callback,
835 	.read_int_callback =	keyspan_pda_rx_interrupt,
836 	.chars_in_buffer =	keyspan_pda_chars_in_buffer,
837 	.throttle =		keyspan_pda_rx_throttle,
838 	.unthrottle =		keyspan_pda_rx_unthrottle,
839 	.ioctl =		keyspan_pda_ioctl,
840 	.set_termios =		keyspan_pda_set_termios,
841 	.break_ctl =		keyspan_pda_break_ctl,
842 	.tiocmget =		keyspan_pda_tiocmget,
843 	.tiocmset =		keyspan_pda_tiocmset,
844 	.attach =		keyspan_pda_startup,
845 	.shutdown =		keyspan_pda_shutdown,
846 };
847 
848 
849 static int __init keyspan_pda_init (void)
850 {
851 	int retval;
852 	retval = usb_serial_register(&keyspan_pda_device);
853 	if (retval)
854 		goto failed_pda_register;
855 #ifdef KEYSPAN
856 	retval = usb_serial_register(&keyspan_pda_fake_device);
857 	if (retval)
858 		goto failed_pda_fake_register;
859 #endif
860 #ifdef XIRCOM
861 	retval = usb_serial_register(&xircom_pgs_fake_device);
862 	if (retval)
863 		goto failed_xircom_register;
864 #endif
865 	retval = usb_register(&keyspan_pda_driver);
866 	if (retval)
867 		goto failed_usb_register;
868 	info(DRIVER_DESC " " DRIVER_VERSION);
869 	return 0;
870 failed_usb_register:
871 #ifdef XIRCOM
872 	usb_serial_deregister(&xircom_pgs_fake_device);
873 failed_xircom_register:
874 #endif /* XIRCOM */
875 #ifdef KEYSPAN
876 	usb_serial_deregister(&keyspan_pda_fake_device);
877 #endif
878 #ifdef KEYSPAN
879 failed_pda_fake_register:
880 #endif
881 	usb_serial_deregister(&keyspan_pda_device);
882 failed_pda_register:
883 	return retval;
884 }
885 
886 
887 static void __exit keyspan_pda_exit (void)
888 {
889 	usb_deregister (&keyspan_pda_driver);
890 	usb_serial_deregister (&keyspan_pda_device);
891 #ifdef KEYSPAN
892 	usb_serial_deregister (&keyspan_pda_fake_device);
893 #endif
894 #ifdef XIRCOM
895 	usb_serial_deregister (&xircom_pgs_fake_device);
896 #endif
897 }
898 
899 
900 module_init(keyspan_pda_init);
901 module_exit(keyspan_pda_exit);
902 
903 MODULE_AUTHOR( DRIVER_AUTHOR );
904 MODULE_DESCRIPTION( DRIVER_DESC );
905 MODULE_LICENSE("GPL");
906 
907 module_param(debug, bool, S_IRUGO | S_IWUSR);
908 MODULE_PARM_DESC(debug, "Debug enabled or not");
909 
910