1 /*    -*- linux-c -*-
2 
3 GTCO digitizer USB driver
4 
5 Use the err() and dbg() macros from usb.h for system logging
6 
7 TO CHECK:  Is pressure done right on report 5?
8 
9 Copyright (C) 2006  GTCO CalComp
10 
11 This program is free software; you can redistribute it and/or
12 modify it under the terms of the GNU General Public License
13 as published by the Free Software Foundation; version 2
14 of the License.
15 
16 This program is distributed in the hope that it will be useful,
17 but WITHOUT ANY WARRANTY; without even the implied warranty of
18 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19 GNU General Public License for more details.
20 
21 You should have received a copy of the GNU General Public License
22 along with this program; if not, write to the Free Software
23 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
24 
25 Permission to use, copy, modify, distribute, and sell this software and its
26 documentation for any purpose is hereby granted without fee, provided that
27 the above copyright notice appear in all copies and that both that
28 copyright notice and this permission notice appear in supporting
29 documentation, and that the name of GTCO-CalComp not be used in advertising
30 or publicity pertaining to distribution of the software without specific,
31 written prior permission. GTCO-CalComp makes no representations about the
32 suitability of this software for any purpose.  It is provided "as is"
33 without express or implied warranty.
34 
35 GTCO-CALCOMP DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
36 INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
37 EVENT SHALL GTCO-CALCOMP BE LIABLE FOR ANY SPECIAL, INDIRECT OR
38 CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
39 DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
40 TORTIOUS ACTIONS, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
41 PERFORMANCE OF THIS SOFTWARE.
42 
43 GTCO CalComp, Inc.
44 7125 Riverwood Drive
45 Columbia, MD 21046
46 
47 Jeremy Roberson jroberson@gtcocalcomp.com
48 Scott Hill shill@gtcocalcomp.com
49 */
50 
51 
52 
53 /*#define DEBUG*/
54 
55 #include <linux/kernel.h>
56 #include <linux/module.h>
57 #include <linux/errno.h>
58 #include <linux/init.h>
59 #include <linux/slab.h>
60 #include <linux/input.h>
61 #include <linux/usb.h>
62 #include <asm/uaccess.h>
63 #include <asm/unaligned.h>
64 #include <asm/byteorder.h>
65 
66 
67 #include <linux/usb/input.h>
68 
69 /* Version with a Major number of 2 is for kernel inclusion only. */
70 #define  GTCO_VERSION   "2.00.0006"
71 
72 
73 /*   MACROS  */
74 
75 #define VENDOR_ID_GTCO	      0x078C
76 #define PID_400               0x400
77 #define PID_401               0x401
78 #define PID_1000              0x1000
79 #define PID_1001              0x1001
80 #define PID_1002              0x1002
81 
82 /* Max size of a single report */
83 #define REPORT_MAX_SIZE       10
84 
85 
86 /* Bitmask whether pen is in range */
87 #define MASK_INRANGE 0x20
88 #define MASK_BUTTON  0x01F
89 
90 #define  PATHLENGTH     64
91 
92 /* DATA STRUCTURES */
93 
94 /* Device table */
95 static const struct usb_device_id gtco_usbid_table[] = {
96 	{ USB_DEVICE(VENDOR_ID_GTCO, PID_400) },
97 	{ USB_DEVICE(VENDOR_ID_GTCO, PID_401) },
98 	{ USB_DEVICE(VENDOR_ID_GTCO, PID_1000) },
99 	{ USB_DEVICE(VENDOR_ID_GTCO, PID_1001) },
100 	{ USB_DEVICE(VENDOR_ID_GTCO, PID_1002) },
101 	{ }
102 };
103 MODULE_DEVICE_TABLE (usb, gtco_usbid_table);
104 
105 
106 /* Structure to hold all of our device specific stuff */
107 struct gtco {
108 
109 	struct input_dev  *inputdevice; /* input device struct pointer  */
110 	struct usb_device *usbdev; /* the usb device for this device */
111 	struct urb        *urbinfo;	 /* urb for incoming reports      */
112 	dma_addr_t        buf_dma;  /* dma addr of the data buffer*/
113 	unsigned char *   buffer;   /* databuffer for reports */
114 
115 	char  usbpath[PATHLENGTH];
116 	int   openCount;
117 
118 	/* Information pulled from Report Descriptor */
119 	u32  usage;
120 	u32  min_X;
121 	u32  max_X;
122 	u32  min_Y;
123 	u32  max_Y;
124 	s8   mintilt_X;
125 	s8   maxtilt_X;
126 	s8   mintilt_Y;
127 	s8   maxtilt_Y;
128 	u32  maxpressure;
129 	u32  minpressure;
130 };
131 
132 
133 
134 /*   Code for parsing the HID REPORT DESCRIPTOR          */
135 
136 /* From HID1.11 spec */
137 struct hid_descriptor
138 {
139 	struct usb_descriptor_header header;
140 	__le16   bcdHID;
141 	u8       bCountryCode;
142 	u8       bNumDescriptors;
143 	u8       bDescriptorType;
144 	__le16   wDescriptorLength;
145 } __attribute__ ((packed));
146 
147 
148 #define HID_DESCRIPTOR_SIZE   9
149 #define HID_DEVICE_TYPE       33
150 #define REPORT_DEVICE_TYPE    34
151 
152 
153 #define PREF_TAG(x)     ((x)>>4)
154 #define PREF_TYPE(x)    ((x>>2)&0x03)
155 #define PREF_SIZE(x)    ((x)&0x03)
156 
157 #define TYPE_MAIN       0
158 #define TYPE_GLOBAL     1
159 #define TYPE_LOCAL      2
160 #define TYPE_RESERVED   3
161 
162 #define TAG_MAIN_INPUT        0x8
163 #define TAG_MAIN_OUTPUT       0x9
164 #define TAG_MAIN_FEATURE      0xB
165 #define TAG_MAIN_COL_START    0xA
166 #define TAG_MAIN_COL_END      0xC
167 
168 #define TAG_GLOB_USAGE        0
169 #define TAG_GLOB_LOG_MIN      1
170 #define TAG_GLOB_LOG_MAX      2
171 #define TAG_GLOB_PHYS_MIN     3
172 #define TAG_GLOB_PHYS_MAX     4
173 #define TAG_GLOB_UNIT_EXP     5
174 #define TAG_GLOB_UNIT         6
175 #define TAG_GLOB_REPORT_SZ    7
176 #define TAG_GLOB_REPORT_ID    8
177 #define TAG_GLOB_REPORT_CNT   9
178 #define TAG_GLOB_PUSH         10
179 #define TAG_GLOB_POP          11
180 
181 #define TAG_GLOB_MAX          12
182 
183 #define DIGITIZER_USAGE_TIP_PRESSURE   0x30
184 #define DIGITIZER_USAGE_TILT_X         0x3D
185 #define DIGITIZER_USAGE_TILT_Y         0x3E
186 
187 
188 /*
189  *   This is an abbreviated parser for the HID Report Descriptor.  We
190  *   know what devices we are talking to, so this is by no means meant
191  *   to be generic.  We can make some safe assumptions:
192  *
193  *   - We know there are no LONG tags, all short
194  *   - We know that we have no MAIN Feature and MAIN Output items
195  *   - We know what the IRQ reports are supposed to look like.
196  *
197  *   The main purpose of this is to use the HID report desc to figure
198  *   out the mins and maxs of the fields in the IRQ reports.  The IRQ
199  *   reports for 400/401 change slightly if the max X is bigger than 64K.
200  *
201  */
parse_hid_report_descriptor(struct gtco * device,char * report,int length)202 static void parse_hid_report_descriptor(struct gtco *device, char * report,
203 					int length)
204 {
205 	int   x, i = 0;
206 
207 	/* Tag primitive vars */
208 	__u8   prefix;
209 	__u8   size;
210 	__u8   tag;
211 	__u8   type;
212 	__u8   data   = 0;
213 	__u16  data16 = 0;
214 	__u32  data32 = 0;
215 
216 	/* For parsing logic */
217 	int   inputnum = 0;
218 	__u32 usage = 0;
219 
220 	/* Global Values, indexed by TAG */
221 	__u32 globalval[TAG_GLOB_MAX];
222 	__u32 oldval[TAG_GLOB_MAX];
223 
224 	/* Debug stuff */
225 	char  maintype = 'x';
226 	char  globtype[12];
227 	int   indent = 0;
228 	char  indentstr[10] = "";
229 
230 
231 	dbg("======>>>>>>PARSE<<<<<<======");
232 
233 	/* Walk  this report and pull out the info we need */
234 	while (i < length) {
235 		prefix = report[i];
236 
237 		/* Skip over prefix */
238 		i++;
239 
240 		/* Determine data size and save the data in the proper variable */
241 		size = PREF_SIZE(prefix);
242 		switch (size) {
243 		case 1:
244 			data = report[i];
245 			break;
246 		case 2:
247 			data16 = get_unaligned_le16(&report[i]);
248 			break;
249 		case 3:
250 			size = 4;
251 			data32 = get_unaligned_le32(&report[i]);
252 			break;
253 		}
254 
255 		/* Skip size of data */
256 		i += size;
257 
258 		/* What we do depends on the tag type */
259 		tag  = PREF_TAG(prefix);
260 		type = PREF_TYPE(prefix);
261 		switch (type) {
262 		case TYPE_MAIN:
263 			strcpy(globtype, "");
264 			switch (tag) {
265 
266 			case TAG_MAIN_INPUT:
267 				/*
268 				 * The INPUT MAIN tag signifies this is
269 				 * information from a report.  We need to
270 				 * figure out what it is and store the
271 				 * min/max values
272 				 */
273 
274 				maintype = 'I';
275 				if (data == 2)
276 					strcpy(globtype, "Variable");
277 				else if (data == 3)
278 					strcpy(globtype, "Var|Const");
279 
280 				dbg("::::: Saving Report: %d input #%d Max: 0x%X(%d) Min:0x%X(%d) of %d bits",
281 				    globalval[TAG_GLOB_REPORT_ID], inputnum,
282 				    globalval[TAG_GLOB_LOG_MAX], globalval[TAG_GLOB_LOG_MAX],
283 				    globalval[TAG_GLOB_LOG_MIN], globalval[TAG_GLOB_LOG_MIN],
284 				    globalval[TAG_GLOB_REPORT_SZ] * globalval[TAG_GLOB_REPORT_CNT]);
285 
286 
287 				/*
288 				  We can assume that the first two input items
289 				  are always the X and Y coordinates.  After
290 				  that, we look for everything else by
291 				  local usage value
292 				 */
293 				switch (inputnum) {
294 				case 0:  /* X coord */
295 					dbg("GER: X Usage: 0x%x", usage);
296 					if (device->max_X == 0) {
297 						device->max_X = globalval[TAG_GLOB_LOG_MAX];
298 						device->min_X = globalval[TAG_GLOB_LOG_MIN];
299 					}
300 					break;
301 
302 				case 1:  /* Y coord */
303 					dbg("GER: Y Usage: 0x%x", usage);
304 					if (device->max_Y == 0) {
305 						device->max_Y = globalval[TAG_GLOB_LOG_MAX];
306 						device->min_Y = globalval[TAG_GLOB_LOG_MIN];
307 					}
308 					break;
309 
310 				default:
311 					/* Tilt X */
312 					if (usage == DIGITIZER_USAGE_TILT_X) {
313 						if (device->maxtilt_X == 0) {
314 							device->maxtilt_X = globalval[TAG_GLOB_LOG_MAX];
315 							device->mintilt_X = globalval[TAG_GLOB_LOG_MIN];
316 						}
317 					}
318 
319 					/* Tilt Y */
320 					if (usage == DIGITIZER_USAGE_TILT_Y) {
321 						if (device->maxtilt_Y == 0) {
322 							device->maxtilt_Y = globalval[TAG_GLOB_LOG_MAX];
323 							device->mintilt_Y = globalval[TAG_GLOB_LOG_MIN];
324 						}
325 					}
326 
327 					/* Pressure */
328 					if (usage == DIGITIZER_USAGE_TIP_PRESSURE) {
329 						if (device->maxpressure == 0) {
330 							device->maxpressure = globalval[TAG_GLOB_LOG_MAX];
331 							device->minpressure = globalval[TAG_GLOB_LOG_MIN];
332 						}
333 					}
334 
335 					break;
336 				}
337 
338 				inputnum++;
339 				break;
340 
341 			case TAG_MAIN_OUTPUT:
342 				maintype = 'O';
343 				break;
344 
345 			case TAG_MAIN_FEATURE:
346 				maintype = 'F';
347 				break;
348 
349 			case TAG_MAIN_COL_START:
350 				maintype = 'S';
351 
352 				if (data == 0) {
353 					dbg("======>>>>>> Physical");
354 					strcpy(globtype, "Physical");
355 				} else
356 					dbg("======>>>>>>");
357 
358 				/* Indent the debug output */
359 				indent++;
360 				for (x = 0; x < indent; x++)
361 					indentstr[x] = '-';
362 				indentstr[x] = 0;
363 
364 				/* Save global tags */
365 				for (x = 0; x < TAG_GLOB_MAX; x++)
366 					oldval[x] = globalval[x];
367 
368 				break;
369 
370 			case TAG_MAIN_COL_END:
371 				dbg("<<<<<<======");
372 				maintype = 'E';
373 				indent--;
374 				for (x = 0; x < indent; x++)
375 					indentstr[x] = '-';
376 				indentstr[x] = 0;
377 
378 				/* Copy global tags back */
379 				for (x = 0; x < TAG_GLOB_MAX; x++)
380 					globalval[x] = oldval[x];
381 
382 				break;
383 			}
384 
385 			switch (size) {
386 			case 1:
387 				dbg("%sMAINTAG:(%d) %c SIZE: %d Data: %s 0x%x",
388 				    indentstr, tag, maintype, size, globtype, data);
389 				break;
390 
391 			case 2:
392 				dbg("%sMAINTAG:(%d) %c SIZE: %d Data: %s 0x%x",
393 				    indentstr, tag, maintype, size, globtype, data16);
394 				break;
395 
396 			case 4:
397 				dbg("%sMAINTAG:(%d) %c SIZE: %d Data: %s 0x%x",
398 				    indentstr, tag, maintype, size, globtype, data32);
399 				break;
400 			}
401 			break;
402 
403 		case TYPE_GLOBAL:
404 			switch (tag) {
405 			case TAG_GLOB_USAGE:
406 				/*
407 				 * First time we hit the global usage tag,
408 				 * it should tell us the type of device
409 				 */
410 				if (device->usage == 0)
411 					device->usage = data;
412 
413 				strcpy(globtype, "USAGE");
414 				break;
415 
416 			case TAG_GLOB_LOG_MIN:
417 				strcpy(globtype, "LOG_MIN");
418 				break;
419 
420 			case TAG_GLOB_LOG_MAX:
421 				strcpy(globtype, "LOG_MAX");
422 				break;
423 
424 			case TAG_GLOB_PHYS_MIN:
425 				strcpy(globtype, "PHYS_MIN");
426 				break;
427 
428 			case TAG_GLOB_PHYS_MAX:
429 				strcpy(globtype, "PHYS_MAX");
430 				break;
431 
432 			case TAG_GLOB_UNIT_EXP:
433 				strcpy(globtype, "EXP");
434 				break;
435 
436 			case TAG_GLOB_UNIT:
437 				strcpy(globtype, "UNIT");
438 				break;
439 
440 			case TAG_GLOB_REPORT_SZ:
441 				strcpy(globtype, "REPORT_SZ");
442 				break;
443 
444 			case TAG_GLOB_REPORT_ID:
445 				strcpy(globtype, "REPORT_ID");
446 				/* New report, restart numbering */
447 				inputnum = 0;
448 				break;
449 
450 			case TAG_GLOB_REPORT_CNT:
451 				strcpy(globtype, "REPORT_CNT");
452 				break;
453 
454 			case TAG_GLOB_PUSH:
455 				strcpy(globtype, "PUSH");
456 				break;
457 
458 			case TAG_GLOB_POP:
459 				strcpy(globtype, "POP");
460 				break;
461 			}
462 
463 			/* Check to make sure we have a good tag number
464 			   so we don't overflow array */
465 			if (tag < TAG_GLOB_MAX) {
466 				switch (size) {
467 				case 1:
468 					dbg("%sGLOBALTAG:%s(%d) SIZE: %d Data: 0x%x",
469 					    indentstr, globtype, tag, size, data);
470 					globalval[tag] = data;
471 					break;
472 
473 				case 2:
474 					dbg("%sGLOBALTAG:%s(%d) SIZE: %d Data: 0x%x",
475 					    indentstr, globtype, tag, size, data16);
476 					globalval[tag] = data16;
477 					break;
478 
479 				case 4:
480 					dbg("%sGLOBALTAG:%s(%d) SIZE: %d Data: 0x%x",
481 					    indentstr, globtype, tag, size, data32);
482 					globalval[tag] = data32;
483 					break;
484 				}
485 			} else {
486 				dbg("%sGLOBALTAG: ILLEGAL TAG:%d SIZE: %d ",
487 				    indentstr, tag, size);
488 			}
489 			break;
490 
491 		case TYPE_LOCAL:
492 			switch (tag) {
493 			case TAG_GLOB_USAGE:
494 				strcpy(globtype, "USAGE");
495 				/* Always 1 byte */
496 				usage = data;
497 				break;
498 
499 			case TAG_GLOB_LOG_MIN:
500 				strcpy(globtype, "MIN");
501 				break;
502 
503 			case TAG_GLOB_LOG_MAX:
504 				strcpy(globtype, "MAX");
505 				break;
506 
507 			default:
508 				strcpy(globtype, "UNKNOWN");
509 				break;
510 			}
511 
512 			switch (size) {
513 			case 1:
514 				dbg("%sLOCALTAG:(%d) %s SIZE: %d Data: 0x%x",
515 				    indentstr, tag, globtype, size, data);
516 				break;
517 
518 			case 2:
519 				dbg("%sLOCALTAG:(%d) %s SIZE: %d Data: 0x%x",
520 				    indentstr, tag, globtype, size, data16);
521 				break;
522 
523 			case 4:
524 				dbg("%sLOCALTAG:(%d) %s SIZE: %d Data: 0x%x",
525 				    indentstr, tag, globtype, size, data32);
526 				break;
527 			}
528 
529 			break;
530 		}
531 	}
532 }
533 
534 /*   INPUT DRIVER Routines                               */
535 
536 /*
537  * Called when opening the input device.  This will submit the URB to
538  * the usb system so we start getting reports
539  */
gtco_input_open(struct input_dev * inputdev)540 static int gtco_input_open(struct input_dev *inputdev)
541 {
542 	struct gtco *device = input_get_drvdata(inputdev);
543 
544 	device->urbinfo->dev = device->usbdev;
545 	if (usb_submit_urb(device->urbinfo, GFP_KERNEL))
546 		return -EIO;
547 
548 	return 0;
549 }
550 
551 /*
552  * Called when closing the input device.  This will unlink the URB
553  */
gtco_input_close(struct input_dev * inputdev)554 static void gtco_input_close(struct input_dev *inputdev)
555 {
556 	struct gtco *device = input_get_drvdata(inputdev);
557 
558 	usb_kill_urb(device->urbinfo);
559 }
560 
561 
562 /*
563  *  Setup input device capabilities.  Tell the input system what this
564  *  device is capable of generating.
565  *
566  *  This information is based on what is read from the HID report and
567  *  placed in the struct gtco structure
568  *
569  */
gtco_setup_caps(struct input_dev * inputdev)570 static void gtco_setup_caps(struct input_dev *inputdev)
571 {
572 	struct gtco *device = input_get_drvdata(inputdev);
573 
574 	/* Which events */
575 	inputdev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS) |
576 		BIT_MASK(EV_MSC);
577 
578 	/* Misc event menu block */
579 	inputdev->mscbit[0] = BIT_MASK(MSC_SCAN) | BIT_MASK(MSC_SERIAL) |
580 		BIT_MASK(MSC_RAW);
581 
582 	/* Absolute values based on HID report info */
583 	input_set_abs_params(inputdev, ABS_X, device->min_X, device->max_X,
584 			     0, 0);
585 	input_set_abs_params(inputdev, ABS_Y, device->min_Y, device->max_Y,
586 			     0, 0);
587 
588 	/* Proximity */
589 	input_set_abs_params(inputdev, ABS_DISTANCE, 0, 1, 0, 0);
590 
591 	/* Tilt & pressure */
592 	input_set_abs_params(inputdev, ABS_TILT_X, device->mintilt_X,
593 			     device->maxtilt_X, 0, 0);
594 	input_set_abs_params(inputdev, ABS_TILT_Y, device->mintilt_Y,
595 			     device->maxtilt_Y, 0, 0);
596 	input_set_abs_params(inputdev, ABS_PRESSURE, device->minpressure,
597 			     device->maxpressure, 0, 0);
598 
599 	/* Transducer */
600 	input_set_abs_params(inputdev, ABS_MISC, 0, 0xFF, 0, 0);
601 }
602 
603 /*   USB Routines  */
604 
605 /*
606  * URB callback routine.  Called when we get IRQ reports from the
607  *  digitizer.
608  *
609  *  This bridges the USB and input device worlds.  It generates events
610  *  on the input device based on the USB reports.
611  */
gtco_urb_callback(struct urb * urbinfo)612 static void gtco_urb_callback(struct urb *urbinfo)
613 {
614 	struct gtco *device = urbinfo->context;
615 	struct input_dev  *inputdev;
616 	int               rc;
617 	u32               val = 0;
618 	s8                valsigned = 0;
619 	char              le_buffer[2];
620 
621 	inputdev = device->inputdevice;
622 
623 	/* Was callback OK? */
624 	if (urbinfo->status == -ECONNRESET ||
625 	    urbinfo->status == -ENOENT ||
626 	    urbinfo->status == -ESHUTDOWN) {
627 
628 		/* Shutdown is occurring. Return and don't queue up any more */
629 		return;
630 	}
631 
632 	if (urbinfo->status != 0) {
633 		/*
634 		 * Some unknown error.  Hopefully temporary. Just go and
635 		 * requeue an URB
636 		 */
637 		goto resubmit;
638 	}
639 
640 	/*
641 	 * Good URB, now process
642 	 */
643 
644 	/* PID dependent when we interpret the report */
645 	if (inputdev->id.product == PID_1000 ||
646 	    inputdev->id.product == PID_1001 ||
647 	    inputdev->id.product == PID_1002) {
648 
649 		/*
650 		 * Switch on the report ID
651 		 * Conveniently, the reports have more information, the higher
652 		 * the report number.  We can just fall through the case
653 		 * statements if we start with the highest number report
654 		 */
655 		switch (device->buffer[0]) {
656 		case 5:
657 			/* Pressure is 9 bits */
658 			val = ((u16)(device->buffer[8]) << 1);
659 			val |= (u16)(device->buffer[7] >> 7);
660 			input_report_abs(inputdev, ABS_PRESSURE,
661 					 device->buffer[8]);
662 
663 			/* Mask out the Y tilt value used for pressure */
664 			device->buffer[7] = (u8)((device->buffer[7]) & 0x7F);
665 
666 			/* Fall thru */
667 		case 4:
668 			/* Tilt */
669 
670 			/* Sign extend these 7 bit numbers.  */
671 			if (device->buffer[6] & 0x40)
672 				device->buffer[6] |= 0x80;
673 
674 			if (device->buffer[7] & 0x40)
675 				device->buffer[7] |= 0x80;
676 
677 
678 			valsigned = (device->buffer[6]);
679 			input_report_abs(inputdev, ABS_TILT_X, (s32)valsigned);
680 
681 			valsigned = (device->buffer[7]);
682 			input_report_abs(inputdev, ABS_TILT_Y, (s32)valsigned);
683 
684 			/* Fall thru */
685 		case 2:
686 		case 3:
687 			/* Convert buttons, only 5 bits possible */
688 			val = (device->buffer[5]) & MASK_BUTTON;
689 
690 			/* We don't apply any meaning to the bitmask,
691 			   just report */
692 			input_event(inputdev, EV_MSC, MSC_SERIAL, val);
693 
694 			/*  Fall thru */
695 		case 1:
696 			/* All reports have X and Y coords in the same place */
697 			val = get_unaligned_le16(&device->buffer[1]);
698 			input_report_abs(inputdev, ABS_X, val);
699 
700 			val = get_unaligned_le16(&device->buffer[3]);
701 			input_report_abs(inputdev, ABS_Y, val);
702 
703 			/* Ditto for proximity bit */
704 			val = device->buffer[5] & MASK_INRANGE ? 1 : 0;
705 			input_report_abs(inputdev, ABS_DISTANCE, val);
706 
707 			/* Report 1 is an exception to how we handle buttons */
708 			/* Buttons are an index, not a bitmask */
709 			if (device->buffer[0] == 1) {
710 
711 				/*
712 				 * Convert buttons, 5 bit index
713 				 * Report value of index set as one,
714 				 * the rest as 0
715 				 */
716 				val = device->buffer[5] & MASK_BUTTON;
717 				dbg("======>>>>>>REPORT 1: val 0x%X(%d)",
718 				    val, val);
719 
720 				/*
721 				 * We don't apply any meaning to the button
722 				 * index, just report it
723 				 */
724 				input_event(inputdev, EV_MSC, MSC_SERIAL, val);
725 			}
726 			break;
727 
728 		case 7:
729 			/* Menu blocks */
730 			input_event(inputdev, EV_MSC, MSC_SCAN,
731 				    device->buffer[1]);
732 			break;
733 		}
734 	}
735 
736 	/* Other pid class */
737 	if (inputdev->id.product == PID_400 ||
738 	    inputdev->id.product == PID_401) {
739 
740 		/* Report 2 */
741 		if (device->buffer[0] == 2) {
742 			/* Menu blocks */
743 			input_event(inputdev, EV_MSC, MSC_SCAN, device->buffer[1]);
744 		}
745 
746 		/*  Report 1 */
747 		if (device->buffer[0] == 1) {
748 			char buttonbyte;
749 
750 			/*  IF X max > 64K, we still a bit from the y report */
751 			if (device->max_X > 0x10000) {
752 
753 				val = (u16)(((u16)(device->buffer[2] << 8)) | (u8)device->buffer[1]);
754 				val |= (u32)(((u8)device->buffer[3] & 0x1) << 16);
755 
756 				input_report_abs(inputdev, ABS_X, val);
757 
758 				le_buffer[0]  = (u8)((u8)(device->buffer[3]) >> 1);
759 				le_buffer[0] |= (u8)((device->buffer[3] & 0x1) << 7);
760 
761 				le_buffer[1]  = (u8)(device->buffer[4] >> 1);
762 				le_buffer[1] |= (u8)((device->buffer[5] & 0x1) << 7);
763 
764 				val = get_unaligned_le16(le_buffer);
765 				input_report_abs(inputdev, ABS_Y, val);
766 
767 				/*
768 				 * Shift the button byte right by one to
769 				 * make it look like the standard report
770 				 */
771 				buttonbyte = device->buffer[5] >> 1;
772 			} else {
773 
774 				val = get_unaligned_le16(&device->buffer[1]);
775 				input_report_abs(inputdev, ABS_X, val);
776 
777 				val = get_unaligned_le16(&device->buffer[3]);
778 				input_report_abs(inputdev, ABS_Y, val);
779 
780 				buttonbyte = device->buffer[5];
781 			}
782 
783 			/* BUTTONS and PROXIMITY */
784 			val = buttonbyte & MASK_INRANGE ? 1 : 0;
785 			input_report_abs(inputdev, ABS_DISTANCE, val);
786 
787 			/* Convert buttons, only 4 bits possible */
788 			val = buttonbyte & 0x0F;
789 #ifdef USE_BUTTONS
790 			for (i = 0; i < 5; i++)
791 				input_report_key(inputdev, BTN_DIGI + i, val & (1 << i));
792 #else
793 			/* We don't apply any meaning to the bitmask, just report */
794 			input_event(inputdev, EV_MSC, MSC_SERIAL, val);
795 #endif
796 
797 			/* TRANSDUCER */
798 			input_report_abs(inputdev, ABS_MISC, device->buffer[6]);
799 		}
800 	}
801 
802 	/* Everybody gets report ID's */
803 	input_event(inputdev, EV_MSC, MSC_RAW,  device->buffer[0]);
804 
805 	/* Sync it up */
806 	input_sync(inputdev);
807 
808  resubmit:
809 	rc = usb_submit_urb(urbinfo, GFP_ATOMIC);
810 	if (rc != 0)
811 		err("usb_submit_urb failed rc=0x%x", rc);
812 }
813 
814 /*
815  *  The probe routine.  This is called when the kernel find the matching USB
816  *   vendor/product.  We do the following:
817  *
818  *    - Allocate mem for a local structure to manage the device
819  *    - Request a HID Report Descriptor from the device and parse it to
820  *      find out the device parameters
821  *    - Create an input device and assign it attributes
822  *   - Allocate an URB so the device can talk to us when the input
823  *      queue is open
824  */
gtco_probe(struct usb_interface * usbinterface,const struct usb_device_id * id)825 static int gtco_probe(struct usb_interface *usbinterface,
826 		      const struct usb_device_id *id)
827 {
828 
829 	struct gtco             *gtco;
830 	struct input_dev        *input_dev;
831 	struct hid_descriptor   *hid_desc;
832 	char                    *report;
833 	int                     result = 0, retry;
834 	int			error;
835 	struct usb_endpoint_descriptor *endpoint;
836 
837 	/* Allocate memory for device structure */
838 	gtco = kzalloc(sizeof(struct gtco), GFP_KERNEL);
839 	input_dev = input_allocate_device();
840 	if (!gtco || !input_dev) {
841 		err("No more memory");
842 		error = -ENOMEM;
843 		goto err_free_devs;
844 	}
845 
846 	/* Set pointer to the input device */
847 	gtco->inputdevice = input_dev;
848 
849 	/* Save interface information */
850 	gtco->usbdev = usb_get_dev(interface_to_usbdev(usbinterface));
851 
852 	/* Allocate some data for incoming reports */
853 	gtco->buffer = usb_alloc_coherent(gtco->usbdev, REPORT_MAX_SIZE,
854 					  GFP_KERNEL, &gtco->buf_dma);
855 	if (!gtco->buffer) {
856 		err("No more memory for us buffers");
857 		error = -ENOMEM;
858 		goto err_free_devs;
859 	}
860 
861 	/* Allocate URB for reports */
862 	gtco->urbinfo = usb_alloc_urb(0, GFP_KERNEL);
863 	if (!gtco->urbinfo) {
864 		err("Failed to allocate URB");
865 		error = -ENOMEM;
866 		goto err_free_buf;
867 	}
868 
869 	/*
870 	 * The endpoint is always altsetting 0, we know this since we know
871 	 * this device only has one interrupt endpoint
872 	 */
873 	endpoint = &usbinterface->altsetting[0].endpoint[0].desc;
874 
875 	/* Some debug */
876 	dbg("gtco # interfaces: %d", usbinterface->num_altsetting);
877 	dbg("num endpoints:     %d", usbinterface->cur_altsetting->desc.bNumEndpoints);
878 	dbg("interface class:   %d", usbinterface->cur_altsetting->desc.bInterfaceClass);
879 	dbg("endpoint: attribute:0x%x type:0x%x", endpoint->bmAttributes, endpoint->bDescriptorType);
880 	if (usb_endpoint_xfer_int(endpoint))
881 		dbg("endpoint: we have interrupt endpoint\n");
882 
883 	dbg("endpoint extra len:%d ", usbinterface->altsetting[0].extralen);
884 
885 	/*
886 	 * Find the HID descriptor so we can find out the size of the
887 	 * HID report descriptor
888 	 */
889 	if (usb_get_extra_descriptor(usbinterface->cur_altsetting,
890 				     HID_DEVICE_TYPE, &hid_desc) != 0){
891 		err("Can't retrieve exta USB descriptor to get hid report descriptor length");
892 		error = -EIO;
893 		goto err_free_urb;
894 	}
895 
896 	dbg("Extra descriptor success: type:%d  len:%d",
897 	    hid_desc->bDescriptorType,  hid_desc->wDescriptorLength);
898 
899 	report = kzalloc(le16_to_cpu(hid_desc->wDescriptorLength), GFP_KERNEL);
900 	if (!report) {
901 		err("No more memory for report");
902 		error = -ENOMEM;
903 		goto err_free_urb;
904 	}
905 
906 	/* Couple of tries to get reply */
907 	for (retry = 0; retry < 3; retry++) {
908 		result = usb_control_msg(gtco->usbdev,
909 					 usb_rcvctrlpipe(gtco->usbdev, 0),
910 					 USB_REQ_GET_DESCRIPTOR,
911 					 USB_RECIP_INTERFACE | USB_DIR_IN,
912 					 REPORT_DEVICE_TYPE << 8,
913 					 0, /* interface */
914 					 report,
915 					 le16_to_cpu(hid_desc->wDescriptorLength),
916 					 5000); /* 5 secs */
917 
918 		dbg("usb_control_msg result: %d", result);
919 		if (result == le16_to_cpu(hid_desc->wDescriptorLength)) {
920 			parse_hid_report_descriptor(gtco, report, result);
921 			break;
922 		}
923 	}
924 
925 	kfree(report);
926 
927 	/* If we didn't get the report, fail */
928 	if (result != le16_to_cpu(hid_desc->wDescriptorLength)) {
929 		err("Failed to get HID Report Descriptor of size: %d",
930 		    hid_desc->wDescriptorLength);
931 		error = -EIO;
932 		goto err_free_urb;
933 	}
934 
935 	/* Create a device file node */
936 	usb_make_path(gtco->usbdev, gtco->usbpath, sizeof(gtco->usbpath));
937 	strlcat(gtco->usbpath, "/input0", sizeof(gtco->usbpath));
938 
939 	/* Set Input device functions */
940 	input_dev->open = gtco_input_open;
941 	input_dev->close = gtco_input_close;
942 
943 	/* Set input device information */
944 	input_dev->name = "GTCO_CalComp";
945 	input_dev->phys = gtco->usbpath;
946 
947 	input_set_drvdata(input_dev, gtco);
948 
949 	/* Now set up all the input device capabilities */
950 	gtco_setup_caps(input_dev);
951 
952 	/* Set input device required ID information */
953 	usb_to_input_id(gtco->usbdev, &input_dev->id);
954 	input_dev->dev.parent = &usbinterface->dev;
955 
956 	/* Setup the URB, it will be posted later on open of input device */
957 	endpoint = &usbinterface->altsetting[0].endpoint[0].desc;
958 
959 	usb_fill_int_urb(gtco->urbinfo,
960 			 gtco->usbdev,
961 			 usb_rcvintpipe(gtco->usbdev,
962 					endpoint->bEndpointAddress),
963 			 gtco->buffer,
964 			 REPORT_MAX_SIZE,
965 			 gtco_urb_callback,
966 			 gtco,
967 			 endpoint->bInterval);
968 
969 	gtco->urbinfo->transfer_dma = gtco->buf_dma;
970 	gtco->urbinfo->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
971 
972 	/* Save gtco pointer in USB interface gtco */
973 	usb_set_intfdata(usbinterface, gtco);
974 
975 	/* All done, now register the input device */
976 	error = input_register_device(input_dev);
977 	if (error)
978 		goto err_free_urb;
979 
980 	return 0;
981 
982  err_free_urb:
983 	usb_free_urb(gtco->urbinfo);
984  err_free_buf:
985 	usb_free_coherent(gtco->usbdev, REPORT_MAX_SIZE,
986 			  gtco->buffer, gtco->buf_dma);
987  err_free_devs:
988 	input_free_device(input_dev);
989 	kfree(gtco);
990 	return error;
991 }
992 
993 /*
994  *  This function is a standard USB function called when the USB device
995  *  is disconnected.  We will get rid of the URV, de-register the input
996  *  device, and free up allocated memory
997  */
gtco_disconnect(struct usb_interface * interface)998 static void gtco_disconnect(struct usb_interface *interface)
999 {
1000 	/* Grab private device ptr */
1001 	struct gtco *gtco = usb_get_intfdata(interface);
1002 
1003 	/* Now reverse all the registration stuff */
1004 	if (gtco) {
1005 		input_unregister_device(gtco->inputdevice);
1006 		usb_kill_urb(gtco->urbinfo);
1007 		usb_free_urb(gtco->urbinfo);
1008 		usb_free_coherent(gtco->usbdev, REPORT_MAX_SIZE,
1009 				  gtco->buffer, gtco->buf_dma);
1010 		kfree(gtco);
1011 	}
1012 
1013 	dev_info(&interface->dev, "gtco driver disconnected\n");
1014 }
1015 
1016 /*   STANDARD MODULE LOAD ROUTINES  */
1017 
1018 static struct usb_driver gtco_driverinfo_table = {
1019 	.name		= "gtco",
1020 	.id_table	= gtco_usbid_table,
1021 	.probe		= gtco_probe,
1022 	.disconnect	= gtco_disconnect,
1023 };
1024 
1025 module_usb_driver(gtco_driverinfo_table);
1026 
1027 MODULE_DESCRIPTION("GTCO digitizer USB driver");
1028 MODULE_LICENSE("GPL");
1029