aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/usb/serial/visor.c
blob: 1aa5d20a5d998d8d4511cae37d24620128f10474 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
/*
 * USB HandSpring Visor, Palm m50x, and Sony Clie driver
 * (supports all of the Palm OS USB devices)
 *
 *	Copyright (C) 1999 - 2004
 *	    Greg Kroah-Hartman (greg@kroah.com)
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License version
 *	2 as published by the Free Software Foundation.
 *
 * See Documentation/usb/usb-serial.txt for more information on using this
 * driver
 *
 */

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/spinlock.h>
#include <linux/uaccess.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "visor.h"

/*
 * Version Information
 */
#define DRIVER_AUTHOR "Greg Kroah-Hartman <greg@kroah.com>"
#define DRIVER_DESC "USB HandSpring Visor / Palm OS driver"

/* function prototypes for a handspring visor */
static int  visor_open(struct tty_struct *tty, struct usb_serial_port *port);
static void visor_close(struct usb_serial_port *port);
static int  visor_write(struct tty_struct *tty, struct usb_serial_port *port,
					const unsigned char *buf, int count);
static int  visor_write_room(struct tty_struct *tty);
static void visor_throttle(struct tty_struct *tty);
static void visor_unthrottle(struct tty_struct *tty);
static int  visor_probe(struct usb_serial *serial,
					const struct usb_device_id *id);
static int  visor_calc_num_ports(struct usb_serial *serial);
static void visor_release(struct usb_serial *serial);
static void visor_write_bulk_callback(struct urb *urb);
static void visor_read_bulk_callback(struct urb *urb);
static void visor_read_int_callback(struct urb *urb);
static int  clie_3_5_startup(struct usb_serial *serial);
static int  treo_attach(struct usb_serial *serial);
static int clie_5_attach(struct usb_serial *serial);
static int palm_os_3_probe(struct usb_serial *serial,
					const struct usb_device_id *id);
static int palm_os_4_probe(struct usb_serial *serial,
					const struct usb_device_id *id);

/* Parameters that may be passed into the module. */
static int debug;
static __u16 vendor;
static __u16 product;

static struct usb_device_id id_table [] = {
	{ USB_DEVICE(HANDSPRING_VENDOR_ID, HANDSPRING_VISOR_ID),
		.driver_info = (kernel_ulong_t)&palm_os_3_probe },
	{ USB_DEVICE(HANDSPRING_VENDOR_ID, HANDSPRING_TREO_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(HANDSPRING_VENDOR_ID, HANDSPRING_TREO600_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(GSPDA_VENDOR_ID, GSPDA_XPLORE_M68_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M500_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M505_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M515_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_I705_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M100_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M125_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M130_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_TUNGSTEN_T_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_TREO_650),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_TUNGSTEN_Z_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_ZIRE_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_4_0_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_S360_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_4_1_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_NX60_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_NZ90V_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_TJ25_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(ACER_VENDOR_ID, ACER_S10_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_SCH_I330_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_SPH_I500_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(TAPWAVE_VENDOR_ID, TAPWAVE_ZODIAC_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(GARMIN_VENDOR_ID, GARMIN_IQUE_3600_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(ACEECA_VENDOR_ID, ACEECA_MEZ1000_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(KYOCERA_VENDOR_ID, KYOCERA_7135_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ USB_DEVICE(FOSSIL_VENDOR_ID, FOSSIL_ABACUS_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ },					/* optional parameter entry */
	{ }					/* Terminating entry */
};

static struct usb_device_id clie_id_5_table [] = {
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_UX50_ID),
		.driver_info = (kernel_ulong_t)&palm_os_4_probe },
	{ },					/* optional parameter entry */
	{ }					/* Terminating entry */
};

static struct usb_device_id clie_id_3_5_table [] = {
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_3_5_ID) },
	{ }					/* Terminating entry */
};

static struct usb_device_id id_table_combined [] = {
	{ USB_DEVICE(HANDSPRING_VENDOR_ID, HANDSPRING_VISOR_ID) },
	{ USB_DEVICE(HANDSPRING_VENDOR_ID, HANDSPRING_TREO_ID) },
	{ USB_DEVICE(HANDSPRING_VENDOR_ID, HANDSPRING_TREO600_ID) },
	{ USB_DEVICE(GSPDA_VENDOR_ID, GSPDA_XPLORE_M68_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M500_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M505_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M515_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_I705_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M100_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M125_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_M130_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_TUNGSTEN_T_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_TREO_650) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_TUNGSTEN_Z_ID) },
	{ USB_DEVICE(PALM_VENDOR_ID, PALM_ZIRE_ID) },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_3_5_ID) },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_4_0_ID) },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_S360_ID) },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_4_1_ID) },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_NX60_ID) },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_NZ90V_ID) },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_UX50_ID) },
	{ USB_DEVICE(SONY_VENDOR_ID, SONY_CLIE_TJ25_ID) },
	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_SCH_I330_ID) },
	{ USB_DEVICE(SAMSUNG_VENDOR_ID, SAMSUNG_SPH_I500_ID) },
	{ USB_DEVICE(TAPWAVE_VENDOR_ID, TAPWAVE_ZODIAC_ID) },
	{ USB_DEVICE(GARMIN_VENDOR_ID, GARMIN_IQUE_3600_ID) },
	{ USB_DEVICE(ACEECA_VENDOR_ID, ACEECA_MEZ1000_ID) },
	{ USB_DEVICE(KYOCERA_VENDOR_ID, KYOCERA_7135_ID) },
	{ USB_DEVICE(FOSSIL_VENDOR_ID, FOSSIL_ABACUS_ID) },
	{ },					/* optional parameter entry */
	{ }					/* Terminating entry */
};

MODULE_DEVICE_TABLE(usb, id_table_combined);

static struct usb_driver visor_driver = {
	.name =		"visor",
	.probe =	usb_serial_probe,
	.disconnect =	usb_serial_disconnect,
	.id_table =	id_table_combined,
	.no_dynamic_id = 	1,
};

/* All of the device info needed for the Handspring Visor,
   and Palm 4.0 devices */
static struct usb_serial_driver handspring_device = {
	.driver = {
		.owner =	THIS_MODULE,
		.name =		"visor",
	},
	.description =		"Handspring Visor / Palm OS",
	.usb_driver =		&visor_driver,
	.id_table =		id_table,
	.num_ports =		2,
	.open =			visor_open,
	.close =		visor_close,
	.throttle =		visor_throttle,
	.unthrottle =		visor_unthrottle,
	.attach =		treo_attach,
	.probe =		visor_probe,
	.calc_num_ports =	visor_calc_num_ports,
	.release =		visor_release,
	.write =		visor_write,
	.write_room =		visor_write_room,
	.write_bulk_callback =	visor_write_bulk_callback,
	.read_bulk_callback =	visor_read_bulk_callback,
	.read_int_callback =	visor_read_int_callback,
};

/* All of the device info needed for the Clie UX50, TH55 Palm 5.0 devices */
static struct usb_serial_driver clie_5_device = {
	.driver = {
		.owner =	THIS_MODULE,
		.name =		"clie_5",
	},
	.description =		"Sony Clie 5.0",
	.usb_driver =		&visor_driver,
	.id_table =		clie_id_5_table,
	.num_ports =		2,
	.open =			visor_open,
	.close =		visor_close,
	.throttle =		visor_throttle,
	.unthrottle =		visor_unthrottle,
	.attach =		clie_5_attach,
	.probe =		visor_probe,
	.calc_num_ports =	visor_calc_num_ports,
	.release =		visor_release,
	.write =		visor_write,
	.write_room =		visor_write_room,
	.write_bulk_callback =	visor_write_bulk_callback,
	.read_bulk_callback =	visor_read_bulk_callback,
	.read_int_callback =	visor_read_int_callback,
};

/* device info for the Sony Clie OS version 3.5 */
static struct usb_serial_driver clie_3_5_device = {
	.driver = {
		.owner =	THIS_MODULE,
		.name =		"clie_3.5",
	},
	.description =		"Sony Clie 3.5",
	.usb_driver =		&visor_driver,
	.id_table =		clie_id_3_5_table,
	.num_ports =		1,
	.open =			visor_open,
	.close =		visor_close,
	.throttle =		visor_throttle,
	.unthrottle =		visor_unthrottle,
	.attach =		clie_3_5_startup,
	.write =		visor_write,
	.write_room =		visor_write_room,
	.write_bulk_callback =	visor_write_bulk_callback,
	.read_bulk_callback =	visor_read_bulk_callback,
};

struct visor_private {
	spinlock_t lock;
	int bytes_in;
	int bytes_out;
	int outstanding_urbs;
	unsigned char throttled;
	unsigned char actually_throttled;
};

/* number of outstanding urbs to prevent userspace DoS from happening */
#define URB_UPPER_LIMIT	42

static int stats;

/******************************************************************************
 * Handspring Visor specific driver functions
 ******************************************************************************/
static int visor_open(struct tty_struct *tty, struct usb_serial_port *port)
{
	struct usb_serial *serial = port->serial;
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	int result = 0;

	dbg("%s - port %d", __func__, port->number);

	if (!port->read_urb) {
		/* this is needed for some brain dead Sony devices */
		dev_err(&port->dev, "Device lied about number of ports, please use a lower one.\n");
		return -ENODEV;
	}

	spin_lock_irqsave(&priv->lock, flags);
	priv->bytes_in = 0;
	priv->bytes_out = 0;
	priv->throttled = 0;
	spin_unlock_irqrestore(&priv->lock, flags);

	/* Start reading from the device */
	usb_fill_bulk_urb(port->read_urb, serial->dev,
			   usb_rcvbulkpipe(serial->dev,
					    port->bulk_in_endpointAddress),
			   port->read_urb->transfer_buffer,
			   port->read_urb->transfer_buffer_length,
			   visor_read_bulk_callback, port);
	result = usb_submit_urb(port->read_urb, GFP_KERNEL);
	if (result) {
		dev_err(&port->dev,
			"%s - failed submitting read urb, error %d\n",
							__func__, result);
		goto exit;
	}

	if (port->interrupt_in_urb) {
		dbg("%s - adding interrupt input for treo", __func__);
		result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
		if (result)
			dev_err(&port->dev,
			    "%s - failed submitting interrupt urb, error %d\n",
							__func__, result);
	}
exit:
	return result;
}


static void visor_close(struct usb_serial_port *port)
{
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned char *transfer_buffer;

	dbg("%s - port %d", __func__, port->number);

	/* shutdown our urbs */
	usb_kill_urb(port->read_urb);
	usb_kill_urb(port->interrupt_in_urb);

	mutex_lock(&port->serial->disc_mutex);
	if (!port->serial->disconnected) {
		/* Try to send shutdown message, unless the device is gone */
		transfer_buffer =  kmalloc(0x12, GFP_KERNEL);
		if (transfer_buffer) {
			usb_control_msg(port->serial->dev,
					 usb_rcvctrlpipe(port->serial->dev, 0),
					 VISOR_CLOSE_NOTIFICATION, 0xc2,
					 0x0000, 0x0000,
					 transfer_buffer, 0x12, 300);
			kfree(transfer_buffer);
		}
	}
	mutex_unlock(&port->serial->disc_mutex);

	if (stats)
		dev_info(&port->dev, "Bytes In = %d  Bytes Out = %d\n",
			 priv->bytes_in, priv->bytes_out);
}


static int visor_write(struct tty_struct *tty, struct usb_serial_port *port,
					const unsigned char *buf, int count)
{
	struct visor_private *priv = usb_get_serial_port_data(port);
	struct usb_serial *serial = port->serial;
	struct urb *urb;
	unsigned char *buffer;
	unsigned long flags;
	int status;

	dbg("%s - port %d", __func__, port->number);

	spin_lock_irqsave(&priv->lock, flags);
	if (priv->outstanding_urbs > URB_UPPER_LIMIT) {
		spin_unlock_irqrestore(&priv->lock, flags);
		dbg("%s - write limit hit\n", __func__);
		return 0;
	}
	priv->outstanding_urbs++;
	spin_unlock_irqrestore(&priv->lock, flags);

	buffer = kmalloc(count, GFP_ATOMIC);
	if (!buffer) {
		dev_err(&port->dev, "out of memory\n");
		count = -ENOMEM;
		goto error_no_buffer;
	}

	urb = usb_alloc_urb(0, GFP_ATOMIC);
	if (!urb) {
		dev_err(&port->dev, "no more free urbs\n");
		count = -ENOMEM;
		goto error_no_urb;
	}

	memcpy(buffer, buf, count);

	usb_serial_debug_data(debug, &port->dev, __func__, count, buffer);

	usb_fill_bulk_urb(urb, serial->dev,
			   usb_sndbulkpipe(serial->dev,
					    port->bulk_out_endpointAddress),
			   buffer, count,
			   visor_write_bulk_callback, port);

	/* send it down the pipe */
	status = usb_submit_urb(urb, GFP_ATOMIC);
	if (status) {
		dev_err(&port->dev,
		   "%s - usb_submit_urb(write bulk) failed with status = %d\n",
							__func__, status);
		count = status;
		goto error;
	} else {
		spin_lock_irqsave(&priv->lock, flags);
		priv->bytes_out += count;
		spin_unlock_irqrestore(&priv->lock, flags);
	}

	/* we are done with this urb, so let the host driver
	 * really free it when it is finished with it */
	usb_free_urb(urb);

	return count;
error:
	usb_free_urb(urb);
error_no_urb:
	kfree(buffer);
error_no_buffer:
	spin_lock_irqsave(&priv->lock, flags);
	--priv->outstanding_urbs;
	spin_unlock_irqrestore(&priv->lock, flags);
	return count;
}


static int visor_write_room(struct tty_struct *tty)
{
	struct usb_serial_port *port = tty->driver_data;
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;

	dbg("%s - port %d", __func__, port->number);

	/*
	 * We really can take anything the user throws at us
	 * but let's pick a nice big number to tell the tty
	 * layer that we have lots of free space, unless we don't.
	 */

	spin_lock_irqsave(&priv->lock, flags);
	if (priv->outstanding_urbs > URB_UPPER_LIMIT * 2 / 3) {
		spin_unlock_irqrestore(&priv->lock, flags);
		dbg("%s - write limit hit\n", __func__);
		return 0;
	}
	spin_unlock_irqrestore(&priv->lock, flags);

	return 2048;
}


static void visor_write_bulk_callback(struct urb *urb)
{
	struct usb_serial_port *port = urb->context;
	struct visor_private *priv = usb_get_serial_port_data(port);
	int status = urb->status;
	unsigned long flags;

	/* free up the transfer buffer, as usb_free_urb() does not do this */
	kfree(urb->transfer_buffer);

	dbg("%s - port %d", __func__, port->number);

	if (status)
		dbg("%s - nonzero write bulk status received: %d",
		    __func__, status);

	spin_lock_irqsave(&priv->lock, flags);
	--priv->outstanding_urbs;
	spin_unlock_irqrestore(&priv->lock, flags);

	usb_serial_port_softint(port);
}


static void visor_read_bulk_callback(struct urb *urb)
{
	struct usb_serial_port *port = urb->context;
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned char *data = urb->transfer_buffer;
	int status = urb->status;
	struct tty_struct *tty;
	int result;
	int available_room = 0;

	dbg("%s - port %d", __func__, port->number);

	if (status) {
		dbg("%s - nonzero read bulk status received: %d",
		    __func__, status);
		return;
	}

	usb_serial_debug_data(debug, &port->dev, __func__,
						urb->actual_length, data);

	if (urb->actual_length) {
		tty = tty_port_tty_get(&port->port);
		if (tty) {
			available_room = tty_buffer_request_room(tty,
							urb->actual_length);
			if (available_room) {
				tty_insert_flip_string(tty, data,
							available_room);
				tty_flip_buffer_push(tty);
			}
			tty_kref_put(tty);
		}
		spin_lock(&priv->lock);
		priv->bytes_in += available_room;

	} else {
		spin_lock(&priv->lock);
	}

	/* Continue trying to always read if we should */
	if (!priv->throttled) {
		usb_fill_bulk_urb(port->read_urb, port->serial->dev,
				   usb_rcvbulkpipe(port->serial->dev,
					   port->bulk_in_endpointAddress),
				   port->read_urb->transfer_buffer,
				   port->read_urb->transfer_buffer_length,
				   visor_read_bulk_callback, port);
		result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
		if (result)
			dev_err(&port->dev,
			    "%s - failed resubmitting read urb, error %d\n",
							__func__, result);
	} else
		priv->actually_throttled = 1;
	spin_unlock(&priv->lock);
}

static void visor_read_int_callback(struct urb *urb)
{
	struct usb_serial_port *port = urb->context;
	int status = urb->status;
	int result;

	switch (status) {
	case 0:
		/* success */
		break;
	case -ECONNRESET:
	case -ENOENT:
	case -ESHUTDOWN:
		/* this urb is terminated, clean up */
		dbg("%s - urb shutting down with status: %d",
		    __func__, status);
		return;
	default:
		dbg("%s - nonzero urb status received: %d",
		    __func__, status);
		goto exit;
	}

	/*
	 * This information is still unknown what it can be used for.
	 * If anyone has an idea, please let the author know...
	 *
	 * Rumor has it this endpoint is used to notify when data
	 * is ready to be read from the bulk ones.
	 */
	usb_serial_debug_data(debug, &port->dev, __func__,
			      urb->actual_length, urb->transfer_buffer);

exit:
	result = usb_submit_urb(urb, GFP_ATOMIC);
	if (result)
		dev_err(&urb->dev->dev,
				"%s - Error %d submitting interrupt urb\n",
							__func__, result);
}

static void visor_throttle(struct tty_struct *tty)
{
	struct usb_serial_port *port = tty->driver_data;
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;

	dbg("%s - port %d", __func__, port->number);
	spin_lock_irqsave(&priv->lock, flags);
	priv->throttled = 1;
	spin_unlock_irqrestore(&priv->lock, flags);
}


static void visor_unthrottle(struct tty_struct *tty)
{
	struct usb_serial_port *port = tty->driver_data;
	struct visor_private *priv = usb_get_serial_port_data(port);
	unsigned long flags;
	int result;

	dbg("%s - port %d", __func__, port->number);
	spin_lock_irqsave(&priv->lock, flags);
	priv->throttled = 0;
	priv->actually_throttled = 0;
	spin_unlock_irqrestore(&priv->lock, flags);

	port->read_urb->dev = port->serial->dev;
	result = usb_submit_urb(port->read_urb, GFP_ATOMIC);
	if (result)
		dev_err(&port->dev,
			"%s - failed submitting read urb, error %d\n",
							__func__, result);
}

static int palm_os_3_probe(struct usb_serial *serial,
						const struct usb_device_id *id)
{
	struct device *dev = &serial->dev->dev;
	struct visor_connection_info *connection_info;
	unsigned char *transfer_buffer;
	char *string;
	int retval = 0;
	int i;
	int num_ports = 0;

	dbg("%s", __func__);

	transfer_buffer = kmalloc(sizeof(*connection_info), GFP_KERNEL);
	if (!transfer_buffer) {
		dev_err(dev, "%s - kmalloc(%Zd) failed.\n", __func__,
			sizeof(*connection_info));
		return -ENOMEM;
	}

	/* send a get connection info request */
	retval = usb_control_msg(serial->dev,
				  usb_rcvctrlpipe(serial->dev, 0),
				  VISOR_GET_CONNECTION_INFORMATION,
				  0xc2, 0x0000, 0x0000, transfer_buffer,
				  sizeof(*connection_info), 300);
	if (retval < 0) {
		dev_err(dev, "%s - error %d getting connection information\n",
			__func__, retval);
		goto exit;
	}

	if (retval == sizeof(*connection_info)) {
			connection_info = (struct visor_connection_info *)
							transfer_buffer;

		num_ports = le16_to_cpu(connection_info->num_ports);
		for (i = 0; i < num_ports; ++i) {
			switch (
			   connection_info->connections[i].port_function_id) {
			case VISOR_FUNCTION_GENERIC:
				string = "Generic";
				break;
			case VISOR_FUNCTION_DEBUGGER:
				string = "Debugger";
				break;
			case VISOR_FUNCTION_HOTSYNC:
				string = "HotSync";
				break;
			case VISOR_FUNCTION_CONSOLE:
				string = "Console";
				break;
			case VISOR_FUNCTION_REMOTE_FILE_SYS:
				string = "Remote File System";
				break;
			default:
				string = "unknown";
				break;
			}
			dev_info(dev, "%s: port %d, is for %s use\n",
				serial->type->description,
				connection_info->connections[i].port, string);
		}
	}
	/*
	* Handle devices that report invalid stuff here.
	*/
	if (num_ports == 0 || num_ports > 2) {
		dev_warn(dev, "%s: No valid connect info available\n",
			serial->type->description);
		num_ports = 2;
	}

	dev_info(dev, "%s: Number of ports: %d\n", serial->type->description,
		num_ports);

	/*
	 * save off our num_ports info so that we can use it in the
	 * calc_num_ports callback
	 */
	usb_set_serial_data(serial, (void *)(long)num_ports);

	/* ask for the number of bytes available, but ignore the
	   response as it is broken */
	retval = usb_control_msg(serial->dev,
				  usb_rcvctrlpipe(serial->dev, 0),
				  VISOR_REQUEST_BYTES_AVAILABLE,
				  0xc2, 0x0000, 0x0005, transfer_buffer,
				  0x02, 300);
	if (retval < 0)
		dev_err(dev, "%s - error %d getting bytes available request\n",
			__func__, retval);
	retval = 0;

exit:
	kfree(transfer_buffer);

	return retval;
}

static int palm_os_4_probe(struct usb_serial *serial,
						const struct usb_device_id *id)
{
	struct device *dev = &serial->dev->dev;
	struct palm_ext_connection_info *connection_info;
	unsigned char *transfer_buffer;
	int retval;

	dbg("%s", __func__);

	transfer_buffer =  kmalloc(sizeof(*connection_info), GFP_KERNEL);
	if (!transfer_buffer) {
		dev_err(dev, "%s - kmalloc(%Zd) failed.\n", __func__,
			sizeof(*connection_info));
		return -ENOMEM;
	}

	retval = usb_control_msg(serial->dev,
				  usb_rcvctrlpipe(serial->dev, 0),
				  PALM_GET_EXT_CONNECTION_INFORMATION,
				  0xc2, 0x0000, 0x0000, transfer_buffer,
				  sizeof(*connection_info), 300);
	if (retval < 0)
		dev_err(dev, "%s - error %d getting connection info\n",
			__func__, retval);
	else
		usb_serial_debug_data(debug, &serial->dev->dev, __func__,
				      retval, transfer_buffer);

	kfree(transfer_buffer);
	return 0;
}


static int visor_probe(struct usb_serial *serial,
					const struct usb_device_id *id)
{
	int retval = 0;
	int (*startup)(struct usb_serial *serial,
					const struct usb_device_id *id);

	dbg("%s", __func__);

	if (serial->dev->actconfig->desc.bConfigurationValue != 1) {
		dev_err(&serial->dev->dev, "active config #%d != 1 ??\n",
			serial->dev->actconfig->desc.bConfigurationValue);
		return -ENODEV;
	}

	if (id->driver_info) {
		startup = (void *)id->driver_info;
		retval = startup(serial, id);
	}

	return retval;
}

static int visor_calc_num_ports(struct usb_serial *serial)
{
	int num_ports = (int)(long)(usb_get_serial_data(serial));

	if (num_ports)
		usb_set_serial_data(serial, NULL);

	return num_ports;
}

static int generic_startup(struct usb_serial *serial)
{
	struct usb_serial_port **ports = serial->port;
	struct visor_private *priv;
	int i;

	for (i = 0; i < serial->num_ports; ++i) {
		priv = kzalloc(sizeof(*priv), GFP_KERNEL);
		if (!priv) {
			while (i-- != 0) {
				priv = usb_get_serial_port_data(ports[i]);
				usb_set_serial_port_data(ports[i], NULL);
				kfree(priv);
			}
			return -ENOMEM;
		}
		spin_lock_init(&priv->lock);
		usb_set_serial_port_data(ports[i], priv);
	}
	return 0;
}

static int clie_3_5_startup(struct usb_serial *serial)
{
	struct device *dev = &serial->dev->dev;
	int result;
	u8 data;

	dbg("%s", __func__);

	/*
	 * Note that PEG-300 series devices expect the following two calls.
	 */

	/* get the config number */
	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
				  USB_REQ_GET_CONFIGURATION, USB_DIR_IN,
				  0, 0, &data, 1, 3000);
	if (result < 0) {
		dev_err(dev, "%s: get config number failed: %d\n",
							__func__, result);
		return result;
	}
	if (result != 1) {
		dev_err(dev, "%s: get config number bad return length: %d\n",
							__func__, result);
		return -EIO;
	}

	/* get the interface number */
	result = usb_control_msg(serial->dev, usb_rcvctrlpipe(serial->dev, 0),
				  USB_REQ_GET_INTERFACE,
				  USB_DIR_IN | USB_RECIP_INTERFACE,
				  0, 0, &data, 1, 3000);
	if (result < 0) {
		dev_err(dev, "%s: get interface number failed: %d\n",
							__func__, result);
		return result;
	}
	if (result != 1) {
		dev_err(dev,
			"%s: get interface number bad return length: %d\n",
							__func__, result);
		return -EIO;
	}

	return generic_startup(serial);
}

static int treo_attach(struct usb_serial *serial)
{
	struct usb_serial_port *swap_port;

	/* Only do this endpoint hack for the Handspring devices with
	 * interrupt in endpoints, which for now are the Treo devices. */
	if (!((le16_to_cpu(serial->dev->descriptor.idVendor)
						== HANDSPRING_VENDOR_ID) ||
		(le16_to_cpu(serial->dev->descriptor.idVendor)
						== KYOCERA_VENDOR_ID)) ||
		(serial->num_interrupt_in == 0))
		goto generic_startup;

	dbg("%s", __func__);

	/*
	* It appears that Treos and Kyoceras want to use the
	* 1st bulk in endpoint to communicate with the 2nd bulk out endpoint,
	* so let's swap the 1st and 2nd bulk in and interrupt endpoints.
	* Note that swapping the bulk out endpoints would break lots of
	* apps that want to communicate on the second port.
	*/
#define COPY_PORT(dest, src)						\
	do { \
		dest->read_urb = src->read_urb;				\
		dest->bulk_in_endpointAddress = src->bulk_in_endpointAddress;\
		dest->bulk_in_buffer = src->bulk_in_buffer;		\
		dest->interrupt_in_urb = src->interrupt_in_urb;		\
		dest->interrupt_in_endpointAddress = \
					src->interrupt_in_endpointAddress;\
		dest->interrupt_in_buffer = src->interrupt_in_buffer;	\
	} while (0);

	swap_port = kmalloc(sizeof(*swap_port), GFP_KERNEL);
	if (!swap_port)
		return -ENOMEM;
	COPY_PORT(swap_port, serial->port[0]);
	COPY_PORT(serial->port[0], serial->port[1]);
	COPY_PORT(serial->port[1], swap_port);
	kfree(swap_port);

generic_startup:
	return generic_startup(serial);
}

static int clie_5_attach(struct usb_serial *serial)
{
	dbg("%s", __func__);

	/* TH55 registers 2 ports.
	   Communication in from the UX50/TH55 uses bulk_in_endpointAddress
	   from port 0. Communication out to the UX50/TH55 uses
	   bulk_out_endpointAddress from port 1

	   Lets do a quick and dirty mapping
	 */

	/* some sanity check */
	if (serial->num_ports < 2)
		return -1;

	/* port 0 now uses the modified endpoint Address */
	serial->port[0]->bulk_out_endpointAddress =
				serial->port[1]->bulk_out_endpointAddress;

	return generic_startup(serial);
}

static void visor_release(struct usb_serial *serial)
{
	struct visor_private *priv;
	int i;

	dbg("%s", __func__);

	for (i = 0; i < serial->num_ports; i++) {
		priv = usb_get_serial_port_data(serial->port[i]);
		kfree(priv);
	}
}

static int __init visor_init(void)
{
	int i, retval;
	/* Only if parameters were passed to us */
	if (vendor > 0 && product > 0) {
		struct usb_device_id usb_dev_temp[] = {
			{
				USB_DEVICE(vendor, product),
				.driver_info =
					(kernel_ulong_t) &palm_os_4_probe
			}
		};

		/* Find the last entry in id_table */
		for (i = 0;; i++) {
			if (id_table[i].idVendor == 0) {
				id_table[i] = usb_dev_temp[0];
				break;
			}
		}
		/* Find the last entry in id_table_combined */
		for (i = 0;; i++) {
			if (id_table_combined[i].idVendor == 0) {
				id_table_combined[i] = usb_dev_temp[0];
				break;
			}
		}
		printk(KERN_INFO KBUILD_MODNAME
		       ": Untested USB device specified at time of module insertion\n");
		printk(KERN_INFO KBUILD_MODNAME
		       ": Warning: This is not guaranteed to work\n");
		printk(KERN_INFO KBUILD_MODNAME
		       ": Using a newer kernel is preferred to this method\n");
		printk(KERN_INFO KBUILD_MODNAME
		       ": Adding Palm OS protocol 4.x support for unknown device: 0x%x/0x%x\n",
			vendor, product);
	}
	retval = usb_serial_register(&handspring_device);
	if (retval)
		goto failed_handspring_register;
	retval = usb_serial_register(&clie_3_5_device);
	if (retval)
		goto failed_clie_3_5_register;
	retval = usb_serial_register(&clie_5_device);
	if (retval)
		goto failed_clie_5_register;
	retval = usb_register(&visor_driver);
	if (retval)
		goto failed_usb_register;
	printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_DESC "\n");

	return 0;
failed_usb_register:
	usb_serial_deregister(&clie_5_device);
failed_clie_5_register:
	usb_serial_deregister(&clie_3_5_device);
failed_clie_3_5_register:
	usb_serial_deregister(&handspring_device);
failed_handspring_register:
	return retval;
}


static void __exit visor_exit (void)
{
	usb_deregister(&visor_driver);
	usb_serial_deregister(&handspring_device);
	usb_serial_deregister(&clie_3_5_device);
	usb_serial_deregister(&clie_5_device);
}


module_init(visor_init);
module_exit(visor_exit);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");

module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");
module_param(stats, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(stats, "Enables statistics or not");

module_param(vendor, ushort, 0);
MODULE_PARM_DESC(vendor, "User specified vendor ID");
module_param(product, ushort, 0);
MODULE_PARM_DESC(product, "User specified product ID");