xref: /openbmc/linux/drivers/usb/serial/keyspan_pda.c (revision 54525552)
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
14  * driver
15  *
16  * (09/07/2001) gkh
17  *	cleaned up the Xircom support.  Added ids for Entregra device which is
18  *	the same as the Xircom device.  Enabled the code to be compiled for
19  *	either Xircom or Keyspan devices.
20  *
21  * (08/11/2001) Cristian M. Craciunescu
22  *	support for Xircom PGSDB9
23  *
24  * (05/31/2001) gkh
25  *	switched from using spinlock to a semaphore, which fixes lots of
26  *	problems.
27  *
28  * (04/08/2001) gb
29  *	Identify version on module load.
30  *
31  * (11/01/2000) Adam J. Richter
32  *	usb_device_id table support
33  *
34  * (10/05/2000) gkh
35  *	Fixed bug with urb->dev not being set properly, now that the usb
36  *	core needs it.
37  *
38  * (08/28/2000) gkh
39  *	Added locks for SMP safeness.
40  *	Fixed MOD_INC and MOD_DEC logic and the ability to open a port more
41  *	than once.
42  *
43  * (07/20/2000) borchers
44  *	- keyspan_pda_write no longer sleeps if it is called on interrupt time;
45  *	  PPP and the line discipline with stty echo on can call write on
46  *	  interrupt time and this would cause an oops if write slept
47  *	- if keyspan_pda_write is in an interrupt, it will not call
48  *	  usb_control_msg (which sleeps) to query the room in the device
49  *	  buffer, it simply uses the current room value it has
50  *	- if the urb is busy or if it is throttled keyspan_pda_write just
51  *	  returns 0, rather than sleeping to wait for this to change; the
52  *	  write_chan code in n_tty.c will sleep if needed before calling
53  *	  keyspan_pda_write again
54  *	- if the device needs to be unthrottled, write now queues up the
55  *	  call to usb_control_msg (which sleeps) to unthrottle the device
56  *	- the wakeups from keyspan_pda_write_bulk_callback are queued rather
57  *	  than done directly from the callback to avoid the race in write_chan
58  *	- keyspan_pda_chars_in_buffer also indicates its buffer is full if the
59  *	  urb status is -EINPROGRESS, meaning it cannot write at the moment
60  *
61  * (07/19/2000) gkh
62  *	Added module_init and module_exit functions to handle the fact that this
63  *	driver is a loadable module now.
64  *
65  * (03/26/2000) gkh
66  *	Split driver up into device specific pieces.
67  *
68  */
69 
70 
71 #include <linux/kernel.h>
72 #include <linux/errno.h>
73 #include <linux/init.h>
74 #include <linux/slab.h>
75 #include <linux/tty.h>
76 #include <linux/tty_driver.h>
77 #include <linux/tty_flip.h>
78 #include <linux/module.h>
79 #include <linux/spinlock.h>
80 #include <linux/workqueue.h>
81 #include <linux/firmware.h>
82 #include <linux/ihex.h>
83 #include <linux/uaccess.h>
84 #include <linux/usb.h>
85 #include <linux/usb/serial.h>
86 
87 static int debug;
88 
89 /* make a simple define to handle if we are compiling keyspan_pda or xircom support */
90 #if defined(CONFIG_USB_SERIAL_KEYSPAN_PDA) || defined(CONFIG_USB_SERIAL_KEYSPAN_PDA_MODULE)
91 	#define KEYSPAN
92 #else
93 	#undef KEYSPAN
94 #endif
95 #if defined(CONFIG_USB_SERIAL_XIRCOM) || defined(CONFIG_USB_SERIAL_XIRCOM_MODULE)
96 	#define XIRCOM
97 #else
98 	#undef XIRCOM
99 #endif
100 
101 /*
102  * Version Information
103  */
104 #define DRIVER_VERSION "v1.1"
105 #define DRIVER_AUTHOR "Brian Warner <warner@lothar.com>"
106 #define DRIVER_DESC "USB Keyspan PDA Converter driver"
107 
108 struct keyspan_pda_private {
109 	int			tx_room;
110 	int			tx_throttled;
111 	struct work_struct			wakeup_work;
112 	struct work_struct			unthrottle_work;
113 	struct usb_serial	*serial;
114 	struct usb_serial_port	*port;
115 };
116 
117 
118 #define KEYSPAN_VENDOR_ID		0x06cd
119 #define KEYSPAN_PDA_FAKE_ID		0x0103
120 #define KEYSPAN_PDA_ID			0x0104 /* no clue */
121 
122 /* For Xircom PGSDB9 and older Entregra version of the same device */
123 #define XIRCOM_VENDOR_ID		0x085a
124 #define XIRCOM_FAKE_ID			0x8027
125 #define ENTREGRA_VENDOR_ID		0x1645
126 #define ENTREGRA_FAKE_ID		0x8093
127 
128 static const struct usb_device_id id_table_combined[] = {
129 #ifdef KEYSPAN
130 	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_FAKE_ID) },
131 #endif
132 #ifdef XIRCOM
133 	{ USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID) },
134 	{ USB_DEVICE(ENTREGRA_VENDOR_ID, ENTREGRA_FAKE_ID) },
135 #endif
136 	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_ID) },
137 	{ }						/* Terminating entry */
138 };
139 
140 MODULE_DEVICE_TABLE(usb, id_table_combined);
141 
142 static struct usb_driver keyspan_pda_driver = {
143 	.name =		"keyspan_pda",
144 	.probe =	usb_serial_probe,
145 	.disconnect =	usb_serial_disconnect,
146 	.id_table =	id_table_combined,
147 	.no_dynamic_id = 	1,
148 };
149 
150 static const struct usb_device_id id_table_std[] = {
151 	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_ID) },
152 	{ }						/* Terminating entry */
153 };
154 
155 #ifdef KEYSPAN
156 static const struct usb_device_id id_table_fake[] = {
157 	{ USB_DEVICE(KEYSPAN_VENDOR_ID, KEYSPAN_PDA_FAKE_ID) },
158 	{ }						/* Terminating entry */
159 };
160 #endif
161 
162 #ifdef XIRCOM
163 static const struct usb_device_id id_table_fake_xircom[] = {
164 	{ USB_DEVICE(XIRCOM_VENDOR_ID, XIRCOM_FAKE_ID) },
165 	{ USB_DEVICE(ENTREGRA_VENDOR_ID, ENTREGRA_FAKE_ID) },
166 	{ }
167 };
168 #endif
169 
170 static void keyspan_pda_wakeup_write(struct work_struct *work)
171 {
172 	struct keyspan_pda_private *priv =
173 		container_of(work, struct keyspan_pda_private, wakeup_work);
174 	struct usb_serial_port *port = priv->port;
175 	struct tty_struct *tty = tty_port_tty_get(&port->port);
176 	if (tty)
177 		tty_wakeup(tty);
178 	tty_kref_put(tty);
179 }
180 
181 static void keyspan_pda_request_unthrottle(struct work_struct *work)
182 {
183 	struct keyspan_pda_private *priv =
184 		container_of(work, struct keyspan_pda_private, unthrottle_work);
185 	struct usb_serial *serial = priv->serial;
186 	int result;
187 
188 	dbg(" request_unthrottle");
189 	/* ask the device to tell us when the tx buffer becomes
190 	   sufficiently empty */
191 	result = usb_control_msg(serial->dev,
192 				 usb_sndctrlpipe(serial->dev, 0),
193 				 7, /* request_unthrottle */
194 				 USB_TYPE_VENDOR | USB_RECIP_INTERFACE
195 				 | USB_DIR_OUT,
196 				 16, /* value: threshold */
197 				 0, /* index */
198 				 NULL,
199 				 0,
200 				 2000);
201 	if (result < 0)
202 		dbg("%s - error %d from usb_control_msg",
203 		    __func__, result);
204 }
205 
206 
207 static void keyspan_pda_rx_interrupt(struct urb *urb)
208 {
209 	struct usb_serial_port *port = urb->context;
210 	struct tty_struct *tty;
211 	unsigned char *data = urb->transfer_buffer;
212 	int retval;
213 	int status = urb->status;
214 	struct keyspan_pda_private *priv;
215 	priv = usb_get_serial_port_data(port);
216 
217 	switch (status) {
218 	case 0:
219 		/* success */
220 		break;
221 	case -ECONNRESET:
222 	case -ENOENT:
223 	case -ESHUTDOWN:
224 		/* this urb is terminated, clean up */
225 		dbg("%s - urb shutting down with status: %d",
226 		    __func__, status);
227 		return;
228 	default:
229 		dbg("%s - nonzero urb status received: %d",
230 		    __func__, status);
231 		goto exit;
232 	}
233 
234 	/* see if the message is data or a status interrupt */
235 	switch (data[0]) {
236 	case 0:
237 		tty = tty_port_tty_get(&port->port);
238 		 /* rest of message is rx data */
239 		if (tty && urb->actual_length) {
240 			tty_insert_flip_string(tty, data + 1,
241 						urb->actual_length - 1);
242 			tty_flip_buffer_push(tty);
243 		}
244 		tty_kref_put(tty);
245 		break;
246 	case 1:
247 		/* status interrupt */
248 		dbg(" rx int, d1=%d, d2=%d", data[1], data[2]);
249 		switch (data[1]) {
250 		case 1: /* modemline change */
251 			break;
252 		case 2: /* tx unthrottle interrupt */
253 			priv->tx_throttled = 0;
254 			/* queue up a wakeup at scheduler time */
255 			schedule_work(&priv->wakeup_work);
256 			break;
257 		default:
258 			break;
259 		}
260 		break;
261 	default:
262 		break;
263 	}
264 
265 exit:
266 	retval = usb_submit_urb(urb, GFP_ATOMIC);
267 	if (retval)
268 		dev_err(&port->dev,
269 			"%s - usb_submit_urb failed with result %d",
270 			__func__, retval);
271 }
272 
273 
274 static void keyspan_pda_rx_throttle(struct tty_struct *tty)
275 {
276 	/* stop receiving characters. We just turn off the URB request, and
277 	   let chars pile up in the device. If we're doing hardware
278 	   flowcontrol, the device will signal the other end when its buffer
279 	   fills up. If we're doing XON/XOFF, this would be a good time to
280 	   send an XOFF, although it might make sense to foist that off
281 	   upon the device too. */
282 	struct usb_serial_port *port = tty->driver_data;
283 	dbg("keyspan_pda_rx_throttle port %d", port->number);
284 	usb_kill_urb(port->interrupt_in_urb);
285 }
286 
287 
288 static void keyspan_pda_rx_unthrottle(struct tty_struct *tty)
289 {
290 	struct usb_serial_port *port = tty->driver_data;
291 	/* just restart the receive interrupt URB */
292 	dbg("keyspan_pda_rx_unthrottle port %d", port->number);
293 	port->interrupt_in_urb->dev = port->serial->dev;
294 	if (usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL))
295 		dbg(" usb_submit_urb(read urb) failed");
296 }
297 
298 
299 static speed_t keyspan_pda_setbaud(struct usb_serial *serial, speed_t baud)
300 {
301 	int rc;
302 	int bindex;
303 
304 	switch (baud) {
305 	case 110:
306 		bindex = 0;
307 		break;
308 	case 300:
309 		bindex = 1;
310 		break;
311 	case 1200:
312 		bindex = 2;
313 		break;
314 	case 2400:
315 		bindex = 3;
316 		break;
317 	case 4800:
318 		bindex = 4;
319 		break;
320 	case 9600:
321 		bindex = 5;
322 		break;
323 	case 19200:
324 		bindex = 6;
325 		break;
326 	case 38400:
327 		bindex = 7;
328 		break;
329 	case 57600:
330 		bindex = 8;
331 		break;
332 	case 115200:
333 		bindex = 9;
334 		break;
335 	default:
336 		bindex = 5;	/* Default to 9600 */
337 		baud = 9600;
338 	}
339 
340 	/* rather than figure out how to sleep while waiting for this
341 	   to complete, I just use the "legacy" API. */
342 	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
343 			     0, /* set baud */
344 			     USB_TYPE_VENDOR
345 			     | USB_RECIP_INTERFACE
346 			     | USB_DIR_OUT, /* type */
347 			     bindex, /* value */
348 			     0, /* index */
349 			     NULL, /* &data */
350 			     0, /* size */
351 			     2000); /* timeout */
352 	if (rc < 0)
353 		return 0;
354 	return baud;
355 }
356 
357 
358 static void keyspan_pda_break_ctl(struct tty_struct *tty, int break_state)
359 {
360 	struct usb_serial_port *port = tty->driver_data;
361 	struct usb_serial *serial = port->serial;
362 	int value;
363 	int result;
364 
365 	if (break_state == -1)
366 		value = 1; /* start break */
367 	else
368 		value = 0; /* clear break */
369 	result = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
370 			4, /* set break */
371 			USB_TYPE_VENDOR | USB_RECIP_INTERFACE | USB_DIR_OUT,
372 			value, 0, NULL, 0, 2000);
373 	if (result < 0)
374 		dbg("%s - error %d from usb_control_msg",
375 		    __func__, result);
376 	/* there is something funky about this.. the TCSBRK that 'cu' performs
377 	   ought to translate into a break_ctl(-1),break_ctl(0) pair HZ/4
378 	   seconds apart, but it feels like the break sent isn't as long as it
379 	   is on /dev/ttyS0 */
380 }
381 
382 
383 static void keyspan_pda_set_termios(struct tty_struct *tty,
384 		struct usb_serial_port *port, struct ktermios *old_termios)
385 {
386 	struct usb_serial *serial = port->serial;
387 	speed_t speed;
388 
389 	/* cflag specifies lots of stuff: number of stop bits, parity, number
390 	   of data bits, baud. What can the device actually handle?:
391 	   CSTOPB (1 stop bit or 2)
392 	   PARENB (parity)
393 	   CSIZE (5bit .. 8bit)
394 	   There is minimal hw support for parity (a PSW bit seems to hold the
395 	   parity of whatever is in the accumulator). The UART either deals
396 	   with 10 bits (start, 8 data, stop) or 11 bits (start, 8 data,
397 	   1 special, stop). So, with firmware changes, we could do:
398 	   8N1: 10 bit
399 	   8N2: 11 bit, extra bit always (mark?)
400 	   8[EOMS]1: 11 bit, extra bit is parity
401 	   7[EOMS]1: 10 bit, b0/b7 is parity
402 	   7[EOMS]2: 11 bit, b0/b7 is parity, extra bit always (mark?)
403 
404 	   HW flow control is dictated by the tty->termios->c_cflags & CRTSCTS
405 	   bit.
406 
407 	   For now, just do baud. */
408 
409 	speed = tty_get_baud_rate(tty);
410 	speed = keyspan_pda_setbaud(serial, speed);
411 
412 	if (speed == 0) {
413 		dbg("can't handle requested baud rate");
414 		/* It hasn't changed so.. */
415 		speed = tty_termios_baud_rate(old_termios);
416 	}
417 	/* Only speed can change so copy the old h/w parameters
418 	   then encode the new speed */
419 	tty_termios_copy_hw(tty->termios, old_termios);
420 	tty_encode_baud_rate(tty, speed, speed);
421 }
422 
423 
424 /* modem control pins: DTR and RTS are outputs and can be controlled.
425    DCD, RI, DSR, CTS are inputs and can be read. All outputs can also be
426    read. The byte passed is: DTR(b7) DCD RI DSR CTS RTS(b2) unused unused */
427 
428 static int keyspan_pda_get_modem_info(struct usb_serial *serial,
429 				      unsigned char *value)
430 {
431 	int rc;
432 	u8 *data;
433 
434 	data = kmalloc(1, GFP_KERNEL);
435 	if (!data)
436 		return -ENOMEM;
437 
438 	rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
439 			     3, /* get pins */
440 			     USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_IN,
441 			     0, 0, data, 1, 2000);
442 	if (rc >= 0)
443 		*value = *data;
444 
445 	kfree(data);
446 	return rc;
447 }
448 
449 
450 static int keyspan_pda_set_modem_info(struct usb_serial *serial,
451 				      unsigned char value)
452 {
453 	int rc;
454 	rc = usb_control_msg(serial->dev, usb_sndctrlpipe(serial->dev, 0),
455 			     3, /* set pins */
456 			     USB_TYPE_VENDOR|USB_RECIP_INTERFACE|USB_DIR_OUT,
457 			     value, 0, NULL, 0, 2000);
458 	return rc;
459 }
460 
461 static int keyspan_pda_tiocmget(struct tty_struct *tty)
462 {
463 	struct usb_serial_port *port = tty->driver_data;
464 	struct usb_serial *serial = port->serial;
465 	int rc;
466 	unsigned char status;
467 	int value;
468 
469 	rc = keyspan_pda_get_modem_info(serial, &status);
470 	if (rc < 0)
471 		return rc;
472 	value =
473 		((status & (1<<7)) ? TIOCM_DTR : 0) |
474 		((status & (1<<6)) ? TIOCM_CAR : 0) |
475 		((status & (1<<5)) ? TIOCM_RNG : 0) |
476 		((status & (1<<4)) ? TIOCM_DSR : 0) |
477 		((status & (1<<3)) ? TIOCM_CTS : 0) |
478 		((status & (1<<2)) ? TIOCM_RTS : 0);
479 	return value;
480 }
481 
482 static int keyspan_pda_tiocmset(struct tty_struct *tty,
483 				unsigned int set, unsigned int clear)
484 {
485 	struct usb_serial_port *port = tty->driver_data;
486 	struct usb_serial *serial = port->serial;
487 	int rc;
488 	unsigned char status;
489 
490 	rc = keyspan_pda_get_modem_info(serial, &status);
491 	if (rc < 0)
492 		return rc;
493 
494 	if (set & TIOCM_RTS)
495 		status |= (1<<2);
496 	if (set & TIOCM_DTR)
497 		status |= (1<<7);
498 
499 	if (clear & TIOCM_RTS)
500 		status &= ~(1<<2);
501 	if (clear & TIOCM_DTR)
502 		status &= ~(1<<7);
503 	rc = keyspan_pda_set_modem_info(serial, status);
504 	return rc;
505 }
506 
507 static int keyspan_pda_write(struct tty_struct *tty,
508 	struct usb_serial_port *port, const unsigned char *buf, int count)
509 {
510 	struct usb_serial *serial = port->serial;
511 	int request_unthrottle = 0;
512 	int rc = 0;
513 	struct keyspan_pda_private *priv;
514 
515 	priv = usb_get_serial_port_data(port);
516 	/* guess how much room is left in the device's ring buffer, and if we
517 	   want to send more than that, check first, updating our notion of
518 	   what is left. If our write will result in no room left, ask the
519 	   device to give us an interrupt when the room available rises above
520 	   a threshold, and hold off all writers (eventually, those using
521 	   select() or poll() too) until we receive that unthrottle interrupt.
522 	   Block if we can't write anything at all, otherwise write as much as
523 	   we can. */
524 	dbg("keyspan_pda_write(%d)", count);
525 	if (count == 0) {
526 		dbg(" write request of 0 bytes");
527 		return 0;
528 	}
529 
530 	/* we might block because of:
531 	   the TX urb is in-flight (wait until it completes)
532 	   the device is full (wait until it says there is room)
533 	*/
534 	spin_lock_bh(&port->lock);
535 	if (port->write_urb_busy || priv->tx_throttled) {
536 		spin_unlock_bh(&port->lock);
537 		return 0;
538 	}
539 	port->write_urb_busy = 1;
540 	spin_unlock_bh(&port->lock);
541 
542 	/* At this point the URB is in our control, nobody else can submit it
543 	   again (the only sudden transition was the one from EINPROGRESS to
544 	   finished).  Also, the tx process is not throttled. So we are
545 	   ready to write. */
546 
547 	count = (count > port->bulk_out_size) ? port->bulk_out_size : count;
548 
549 	/* Check if we might overrun the Tx buffer.   If so, ask the
550 	   device how much room it really has.  This is done only on
551 	   scheduler time, since usb_control_msg() sleeps. */
552 	if (count > priv->tx_room && !in_interrupt()) {
553 		u8 *room;
554 
555 		room = kmalloc(1, GFP_KERNEL);
556 		if (!room) {
557 			rc = -ENOMEM;
558 			goto exit;
559 		}
560 
561 		rc = usb_control_msg(serial->dev,
562 				     usb_rcvctrlpipe(serial->dev, 0),
563 				     6, /* write_room */
564 				     USB_TYPE_VENDOR | USB_RECIP_INTERFACE
565 				     | USB_DIR_IN,
566 				     0, /* value: 0 means "remaining room" */
567 				     0, /* index */
568 				     room,
569 				     1,
570 				     2000);
571 		if (rc > 0) {
572 			dbg(" roomquery says %d", *room);
573 			priv->tx_room = *room;
574 		}
575 		kfree(room);
576 		if (rc < 0) {
577 			dbg(" roomquery failed");
578 			goto exit;
579 		}
580 		if (rc == 0) {
581 			dbg(" roomquery returned 0 bytes");
582 			rc = -EIO; /* device didn't return any data */
583 			goto exit;
584 		}
585 	}
586 	if (count > priv->tx_room) {
587 		/* we're about to completely fill the Tx buffer, so
588 		   we'll be throttled afterwards. */
589 		count = priv->tx_room;
590 		request_unthrottle = 1;
591 	}
592 
593 	if (count) {
594 		/* now transfer data */
595 		memcpy(port->write_urb->transfer_buffer, buf, count);
596 		/* send the data out the bulk port */
597 		port->write_urb->transfer_buffer_length = count;
598 
599 		priv->tx_room -= count;
600 
601 		port->write_urb->dev = port->serial->dev;
602 		rc = usb_submit_urb(port->write_urb, GFP_ATOMIC);
603 		if (rc) {
604 			dbg(" usb_submit_urb(write bulk) failed");
605 			goto exit;
606 		}
607 	} else {
608 		/* There wasn't any room left, so we are throttled until
609 		   the buffer empties a bit */
610 		request_unthrottle = 1;
611 	}
612 
613 	if (request_unthrottle) {
614 		priv->tx_throttled = 1; /* block writers */
615 		schedule_work(&priv->unthrottle_work);
616 	}
617 
618 	rc = count;
619 exit:
620 	if (rc < 0)
621 		port->write_urb_busy = 0;
622 	return rc;
623 }
624 
625 
626 static void keyspan_pda_write_bulk_callback(struct urb *urb)
627 {
628 	struct usb_serial_port *port = urb->context;
629 	struct keyspan_pda_private *priv;
630 
631 	port->write_urb_busy = 0;
632 	priv = usb_get_serial_port_data(port);
633 
634 	/* queue up a wakeup at scheduler time */
635 	schedule_work(&priv->wakeup_work);
636 }
637 
638 
639 static int keyspan_pda_write_room(struct tty_struct *tty)
640 {
641 	struct usb_serial_port *port = tty->driver_data;
642 	struct keyspan_pda_private *priv;
643 	priv = usb_get_serial_port_data(port);
644 	/* used by n_tty.c for processing of tabs and such. Giving it our
645 	   conservative guess is probably good enough, but needs testing by
646 	   running a console through the device. */
647 	return priv->tx_room;
648 }
649 
650 
651 static int keyspan_pda_chars_in_buffer(struct tty_struct *tty)
652 {
653 	struct usb_serial_port *port = tty->driver_data;
654 	struct keyspan_pda_private *priv;
655 	unsigned long flags;
656 	int ret = 0;
657 
658 	priv = usb_get_serial_port_data(port);
659 
660 	/* when throttled, return at least WAKEUP_CHARS to tell select() (via
661 	   n_tty.c:normal_poll() ) that we're not writeable. */
662 
663 	spin_lock_irqsave(&port->lock, flags);
664 	if (port->write_urb_busy || priv->tx_throttled)
665 		ret = 256;
666 	spin_unlock_irqrestore(&port->lock, flags);
667 	return ret;
668 }
669 
670 
671 static void keyspan_pda_dtr_rts(struct usb_serial_port *port, int on)
672 {
673 	struct usb_serial *serial = port->serial;
674 
675 	if (serial->dev) {
676 		if (on)
677 			keyspan_pda_set_modem_info(serial, (1<<7) | (1<< 2));
678 		else
679 			keyspan_pda_set_modem_info(serial, 0);
680 	}
681 }
682 
683 
684 static int keyspan_pda_open(struct tty_struct *tty,
685 					struct usb_serial_port *port)
686 {
687 	struct usb_serial *serial = port->serial;
688 	u8 *room;
689 	int rc = 0;
690 	struct keyspan_pda_private *priv;
691 
692 	/* find out how much room is in the Tx ring */
693 	room = kmalloc(1, GFP_KERNEL);
694 	if (!room)
695 		return -ENOMEM;
696 
697 	rc = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
698 			     6, /* write_room */
699 			     USB_TYPE_VENDOR | USB_RECIP_INTERFACE
700 			     | USB_DIR_IN,
701 			     0, /* value */
702 			     0, /* index */
703 			     room,
704 			     1,
705 			     2000);
706 	if (rc < 0) {
707 		dbg("%s - roomquery failed", __func__);
708 		goto error;
709 	}
710 	if (rc == 0) {
711 		dbg("%s - roomquery returned 0 bytes", __func__);
712 		rc = -EIO;
713 		goto error;
714 	}
715 	priv = usb_get_serial_port_data(port);
716 	priv->tx_room = *room;
717 	priv->tx_throttled = *room ? 0 : 1;
718 
719 	/*Start reading from the device*/
720 	port->interrupt_in_urb->dev = serial->dev;
721 	rc = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
722 	if (rc) {
723 		dbg("%s - usb_submit_urb(read int) failed", __func__);
724 		goto error;
725 	}
726 error:
727 	kfree(room);
728 	return rc;
729 }
730 static void keyspan_pda_close(struct usb_serial_port *port)
731 {
732 	struct usb_serial *serial = port->serial;
733 
734 	if (serial->dev) {
735 		/* shutdown our bulk reads and writes */
736 		usb_kill_urb(port->write_urb);
737 		usb_kill_urb(port->interrupt_in_urb);
738 	}
739 }
740 
741 
742 /* download the firmware to a "fake" device (pre-renumeration) */
743 static int keyspan_pda_fake_startup(struct usb_serial *serial)
744 {
745 	int response;
746 	const char *fw_name;
747 	const struct ihex_binrec *record;
748 	const struct firmware *fw;
749 
750 	/* download the firmware here ... */
751 	response = ezusb_set_reset(serial, 1);
752 
753 	if (0) { ; }
754 #ifdef KEYSPAN
755 	else if (le16_to_cpu(serial->dev->descriptor.idVendor) == KEYSPAN_VENDOR_ID)
756 		fw_name = "keyspan_pda/keyspan_pda.fw";
757 #endif
758 #ifdef XIRCOM
759 	else if ((le16_to_cpu(serial->dev->descriptor.idVendor) == XIRCOM_VENDOR_ID) ||
760 		 (le16_to_cpu(serial->dev->descriptor.idVendor) == ENTREGRA_VENDOR_ID))
761 		fw_name = "keyspan_pda/xircom_pgs.fw";
762 #endif
763 	else {
764 		dev_err(&serial->dev->dev, "%s: unknown vendor, aborting.\n",
765 			__func__);
766 		return -ENODEV;
767 	}
768 	if (request_ihex_firmware(&fw, fw_name, &serial->dev->dev)) {
769 		dev_err(&serial->dev->dev, "failed to load firmware \"%s\"\n",
770 			fw_name);
771 		return -ENOENT;
772 	}
773 	record = (const struct ihex_binrec *)fw->data;
774 
775 	while (record) {
776 		response = ezusb_writememory(serial, be32_to_cpu(record->addr),
777 					     (unsigned char *)record->data,
778 					     be16_to_cpu(record->len), 0xa0);
779 		if (response < 0) {
780 			dev_err(&serial->dev->dev, "ezusb_writememory failed "
781 				"for Keyspan PDA firmware (%d %04X %p %d)\n",
782 				response, be32_to_cpu(record->addr),
783 				record->data, be16_to_cpu(record->len));
784 			break;
785 		}
786 		record = ihex_next_binrec(record);
787 	}
788 	release_firmware(fw);
789 	/* bring device out of reset. Renumeration will occur in a moment
790 	   and the new device will bind to the real driver */
791 	response = ezusb_set_reset(serial, 0);
792 
793 	/* we want this device to fail to have a driver assigned to it. */
794 	return 1;
795 }
796 
797 #ifdef KEYSPAN
798 MODULE_FIRMWARE("keyspan_pda/keyspan_pda.fw");
799 #endif
800 #ifdef XIRCOM
801 MODULE_FIRMWARE("keyspan_pda/xircom_pgs.fw");
802 #endif
803 
804 static int keyspan_pda_startup(struct usb_serial *serial)
805 {
806 
807 	struct keyspan_pda_private *priv;
808 
809 	/* allocate the private data structures for all ports. Well, for all
810 	   one ports. */
811 
812 	priv = kmalloc(sizeof(struct keyspan_pda_private), GFP_KERNEL);
813 	if (!priv)
814 		return 1; /* error */
815 	usb_set_serial_port_data(serial->port[0], priv);
816 	init_waitqueue_head(&serial->port[0]->write_wait);
817 	INIT_WORK(&priv->wakeup_work, keyspan_pda_wakeup_write);
818 	INIT_WORK(&priv->unthrottle_work, keyspan_pda_request_unthrottle);
819 	priv->serial = serial;
820 	priv->port = serial->port[0];
821 	return 0;
822 }
823 
824 static void keyspan_pda_release(struct usb_serial *serial)
825 {
826 	dbg("%s", __func__);
827 
828 	kfree(usb_get_serial_port_data(serial->port[0]));
829 }
830 
831 #ifdef KEYSPAN
832 static struct usb_serial_driver keyspan_pda_fake_device = {
833 	.driver = {
834 		.owner =	THIS_MODULE,
835 		.name =		"keyspan_pda_pre",
836 	},
837 	.description =		"Keyspan PDA - (prerenumeration)",
838 	.usb_driver = 		&keyspan_pda_driver,
839 	.id_table =		id_table_fake,
840 	.num_ports =		1,
841 	.attach =		keyspan_pda_fake_startup,
842 };
843 #endif
844 
845 #ifdef XIRCOM
846 static struct usb_serial_driver xircom_pgs_fake_device = {
847 	.driver = {
848 		.owner =	THIS_MODULE,
849 		.name =		"xircom_no_firm",
850 	},
851 	.description =		"Xircom / Entregra PGS - (prerenumeration)",
852 	.usb_driver = 		&keyspan_pda_driver,
853 	.id_table =		id_table_fake_xircom,
854 	.num_ports =		1,
855 	.attach =		keyspan_pda_fake_startup,
856 };
857 #endif
858 
859 static struct usb_serial_driver keyspan_pda_device = {
860 	.driver = {
861 		.owner =	THIS_MODULE,
862 		.name =		"keyspan_pda",
863 	},
864 	.description =		"Keyspan PDA",
865 	.usb_driver = 		&keyspan_pda_driver,
866 	.id_table =		id_table_std,
867 	.num_ports =		1,
868 	.dtr_rts =		keyspan_pda_dtr_rts,
869 	.open =			keyspan_pda_open,
870 	.close =		keyspan_pda_close,
871 	.write =		keyspan_pda_write,
872 	.write_room =		keyspan_pda_write_room,
873 	.write_bulk_callback = 	keyspan_pda_write_bulk_callback,
874 	.read_int_callback =	keyspan_pda_rx_interrupt,
875 	.chars_in_buffer =	keyspan_pda_chars_in_buffer,
876 	.throttle =		keyspan_pda_rx_throttle,
877 	.unthrottle =		keyspan_pda_rx_unthrottle,
878 	.set_termios =		keyspan_pda_set_termios,
879 	.break_ctl =		keyspan_pda_break_ctl,
880 	.tiocmget =		keyspan_pda_tiocmget,
881 	.tiocmset =		keyspan_pda_tiocmset,
882 	.attach =		keyspan_pda_startup,
883 	.release =		keyspan_pda_release,
884 };
885 
886 
887 static int __init keyspan_pda_init(void)
888 {
889 	int retval;
890 	retval = usb_serial_register(&keyspan_pda_device);
891 	if (retval)
892 		goto failed_pda_register;
893 #ifdef KEYSPAN
894 	retval = usb_serial_register(&keyspan_pda_fake_device);
895 	if (retval)
896 		goto failed_pda_fake_register;
897 #endif
898 #ifdef XIRCOM
899 	retval = usb_serial_register(&xircom_pgs_fake_device);
900 	if (retval)
901 		goto failed_xircom_register;
902 #endif
903 	retval = usb_register(&keyspan_pda_driver);
904 	if (retval)
905 		goto failed_usb_register;
906 	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
907 	       DRIVER_DESC "\n");
908 	return 0;
909 failed_usb_register:
910 #ifdef XIRCOM
911 	usb_serial_deregister(&xircom_pgs_fake_device);
912 failed_xircom_register:
913 #endif /* XIRCOM */
914 #ifdef KEYSPAN
915 	usb_serial_deregister(&keyspan_pda_fake_device);
916 #endif
917 #ifdef KEYSPAN
918 failed_pda_fake_register:
919 #endif
920 	usb_serial_deregister(&keyspan_pda_device);
921 failed_pda_register:
922 	return retval;
923 }
924 
925 
926 static void __exit keyspan_pda_exit(void)
927 {
928 	usb_deregister(&keyspan_pda_driver);
929 	usb_serial_deregister(&keyspan_pda_device);
930 #ifdef KEYSPAN
931 	usb_serial_deregister(&keyspan_pda_fake_device);
932 #endif
933 #ifdef XIRCOM
934 	usb_serial_deregister(&xircom_pgs_fake_device);
935 #endif
936 }
937 
938 
939 module_init(keyspan_pda_init);
940 module_exit(keyspan_pda_exit);
941 
942 MODULE_AUTHOR(DRIVER_AUTHOR);
943 MODULE_DESCRIPTION(DRIVER_DESC);
944 MODULE_LICENSE("GPL");
945 
946 module_param(debug, bool, S_IRUGO | S_IWUSR);
947 MODULE_PARM_DESC(debug, "Debug enabled or not");
948 
949