xref: /linux/drivers/hid/wacom_sys.c (revision afca12e35e711ae8f97e835a3704cc305592eac9)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  USB Wacom tablet support - system specific code
4  */
5 
6 #include "wacom_wac.h"
7 #include "wacom.h"
8 #include <linux/input/mt.h>
9 
10 #define WAC_MSG_RETRIES		5
11 #define WAC_CMD_RETRIES		10
12 
13 #define DEV_ATTR_RW_PERM (S_IRUGO | S_IWUSR | S_IWGRP)
14 #define DEV_ATTR_WO_PERM (S_IWUSR | S_IWGRP)
15 #define DEV_ATTR_RO_PERM (S_IRUSR | S_IRGRP)
16 
17 static int wacom_get_report(struct hid_device *hdev, u8 type, u8 *buf,
18 			    size_t size, unsigned int retries)
19 {
20 	int retval;
21 
22 	do {
23 		retval = hid_hw_raw_request(hdev, buf[0], buf, size, type,
24 				HID_REQ_GET_REPORT);
25 	} while ((retval == -ETIMEDOUT || retval == -EAGAIN) && --retries);
26 
27 	if (retval < 0)
28 		hid_err(hdev, "wacom_get_report: ran out of retries "
29 			"(last error = %d)\n", retval);
30 
31 	return retval;
32 }
33 
34 static int wacom_set_report(struct hid_device *hdev, u8 type, u8 *buf,
35 			    size_t size, unsigned int retries)
36 {
37 	int retval;
38 
39 	do {
40 		retval = hid_hw_raw_request(hdev, buf[0], buf, size, type,
41 				HID_REQ_SET_REPORT);
42 	} while ((retval == -ETIMEDOUT || retval == -EAGAIN) && --retries);
43 
44 	if (retval < 0)
45 		hid_err(hdev, "wacom_set_report: ran out of retries "
46 			"(last error = %d)\n", retval);
47 
48 	return retval;
49 }
50 
51 static void wacom_wac_queue_insert(struct hid_device *hdev,
52 				   struct kfifo_rec_ptr_2 *fifo,
53 				   u8 *raw_data, int size)
54 {
55 	bool warned = false;
56 
57 	while (kfifo_avail(fifo) < size) {
58 		if (!warned)
59 			hid_warn(hdev, "%s: kfifo has filled, starting to drop events\n", __func__);
60 		warned = true;
61 
62 		kfifo_skip(fifo);
63 	}
64 
65 	kfifo_in(fifo, raw_data, size);
66 }
67 
68 static void wacom_wac_queue_flush(struct hid_device *hdev,
69 				  struct kfifo_rec_ptr_2 *fifo)
70 {
71 	while (!kfifo_is_empty(fifo)) {
72 		u8 buf[WACOM_PKGLEN_MAX];
73 		int size;
74 		int err;
75 
76 		size = kfifo_out(fifo, buf, sizeof(buf));
77 		err = hid_report_raw_event(hdev, HID_INPUT_REPORT, buf, size, false);
78 		if (err) {
79 			hid_warn(hdev, "%s: unable to flush event due to error %d\n",
80 				 __func__, err);
81 		}
82 	}
83 }
84 
85 static int wacom_wac_pen_serial_enforce(struct hid_device *hdev,
86 		struct hid_report *report, u8 *raw_data, int report_size)
87 {
88 	struct wacom *wacom = hid_get_drvdata(hdev);
89 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
90 	struct wacom_features *features = &wacom_wac->features;
91 	bool flush = false;
92 	bool insert = false;
93 	int i, j;
94 
95 	if (wacom_wac->serial[0] || !(features->quirks & WACOM_QUIRK_TOOLSERIAL))
96 		return 0;
97 
98 	/* Queue events which have invalid tool type or serial number */
99 	for (i = 0; i < report->maxfield; i++) {
100 		for (j = 0; j < report->field[i]->maxusage; j++) {
101 			struct hid_field *field = report->field[i];
102 			struct hid_usage *usage = &field->usage[j];
103 			unsigned int equivalent_usage = wacom_equivalent_usage(usage->hid);
104 			unsigned int offset;
105 			unsigned int size;
106 			unsigned int value;
107 
108 			if (equivalent_usage != HID_DG_INRANGE &&
109 			    equivalent_usage != HID_DG_TOOLSERIALNUMBER &&
110 			    equivalent_usage != WACOM_HID_WD_SERIALHI &&
111 			    equivalent_usage != WACOM_HID_WD_TOOLTYPE)
112 				continue;
113 
114 			offset = field->report_offset;
115 			size = field->report_size;
116 			value = hid_field_extract(hdev, raw_data+1, offset + j * size, size);
117 
118 			/* If we go out of range, we need to flush the queue ASAP */
119 			if (equivalent_usage == HID_DG_INRANGE)
120 				value = !value;
121 
122 			if (value) {
123 				flush = true;
124 				switch (equivalent_usage) {
125 				case HID_DG_TOOLSERIALNUMBER:
126 					wacom_wac->serial[0] = value;
127 					break;
128 
129 				case WACOM_HID_WD_SERIALHI:
130 					wacom_wac->serial[0] |= ((__u64)value) << 32;
131 					break;
132 
133 				case WACOM_HID_WD_TOOLTYPE:
134 					wacom_wac->id[0] = value;
135 					break;
136 				}
137 			}
138 			else {
139 				insert = true;
140 			}
141 		}
142 	}
143 
144 	if (flush)
145 		wacom_wac_queue_flush(hdev, wacom_wac->pen_fifo);
146 	else if (insert)
147 		wacom_wac_queue_insert(hdev, wacom_wac->pen_fifo,
148 				       raw_data, report_size);
149 
150 	return insert && !flush;
151 }
152 
153 static int wacom_raw_event(struct hid_device *hdev, struct hid_report *report,
154 		u8 *raw_data, int size)
155 {
156 	struct wacom *wacom = hid_get_drvdata(hdev);
157 
158 	if (wacom->wacom_wac.features.type == BOOTLOADER)
159 		return 0;
160 
161 	if (size > WACOM_PKGLEN_MAX)
162 		return 1;
163 
164 	if (wacom_wac_pen_serial_enforce(hdev, report, raw_data, size))
165 		return -1;
166 
167 	memcpy(wacom->wacom_wac.data, raw_data, size);
168 
169 	wacom_wac_irq(&wacom->wacom_wac, size);
170 
171 	return 0;
172 }
173 
174 static int wacom_open(struct input_dev *dev)
175 {
176 	struct wacom *wacom = input_get_drvdata(dev);
177 
178 	return hid_hw_open(wacom->hdev);
179 }
180 
181 static void wacom_close(struct input_dev *dev)
182 {
183 	struct wacom *wacom = input_get_drvdata(dev);
184 
185 	/*
186 	 * wacom->hdev should never be null, but surprisingly, I had the case
187 	 * once while unplugging the Wacom Wireless Receiver.
188 	 */
189 	if (wacom->hdev)
190 		hid_hw_close(wacom->hdev);
191 }
192 
193 /*
194  * Calculate the resolution of the X or Y axis using hidinput_calc_abs_res.
195  */
196 static int wacom_calc_hid_res(int logical_extents, int physical_extents,
197 			       unsigned unit, int exponent)
198 {
199 	struct hid_field field = {
200 		.logical_maximum = logical_extents,
201 		.physical_maximum = physical_extents,
202 		.unit = unit,
203 		.unit_exponent = exponent,
204 	};
205 
206 	return hidinput_calc_abs_res(&field, ABS_X);
207 }
208 
209 static void wacom_hid_usage_quirk(struct hid_device *hdev,
210 		struct hid_field *field, struct hid_usage *usage)
211 {
212 	struct wacom *wacom = hid_get_drvdata(hdev);
213 	struct wacom_features *features = &wacom->wacom_wac.features;
214 	unsigned int equivalent_usage = wacom_equivalent_usage(usage->hid);
215 
216 	/*
217 	 * The Dell Canvas 27 needs to be switched to its vendor-defined
218 	 * report to provide the best resolution.
219 	 */
220 	if (hdev->vendor == USB_VENDOR_ID_WACOM &&
221 	    hdev->product == 0x4200 &&
222 	    field->application == HID_UP_MSVENDOR) {
223 		wacom->wacom_wac.mode_report = field->report->id;
224 		wacom->wacom_wac.mode_value = 2;
225 	}
226 
227 	/*
228 	 * ISDv4 devices which predate HID's adoption of the
229 	 * HID_DG_BARELSWITCH2 usage use 0x000D0000 in its
230 	 * position instead. We can accurately detect if a
231 	 * usage with that value should be HID_DG_BARRELSWITCH2
232 	 * based on the surrounding usages, which have remained
233 	 * constant across generations.
234 	 */
235 	if (features->type == HID_GENERIC &&
236 	    usage->hid == 0x000D0000 &&
237 	    field->application == HID_DG_PEN &&
238 	    field->physical == HID_DG_STYLUS) {
239 		int i = usage->usage_index;
240 
241 		if (i-4 >= 0 && i+1 < field->maxusage &&
242 		    field->usage[i-4].hid == HID_DG_TIPSWITCH &&
243 		    field->usage[i-3].hid == HID_DG_BARRELSWITCH &&
244 		    field->usage[i-2].hid == HID_DG_ERASER &&
245 		    field->usage[i-1].hid == HID_DG_INVERT &&
246 		    field->usage[i+1].hid == HID_DG_INRANGE) {
247 			usage->hid = HID_DG_BARRELSWITCH2;
248 		}
249 	}
250 
251 	/*
252 	 * Wacom's AES devices use different vendor-defined usages to
253 	 * report serial number information compared to their branded
254 	 * hardware. The usages are also sometimes ill-defined and do
255 	 * not have the correct logical min/max values set. Lets patch
256 	 * the descriptor to use the branded usage convention and fix
257 	 * the errors.
258 	 */
259 	if (usage->hid == WACOM_HID_WT_SERIALNUMBER &&
260 	    field->report_size == 16 &&
261 	    field->index + 2 < field->report->maxfield) {
262 		struct hid_field *a = field->report->field[field->index + 1];
263 		struct hid_field *b = field->report->field[field->index + 2];
264 
265 		if (a->maxusage > 0 &&
266 		    a->usage[0].hid == HID_DG_TOOLSERIALNUMBER &&
267 		    a->report_size == 32 &&
268 		    b->maxusage > 0 &&
269 		    b->usage[0].hid == 0xFF000000 &&
270 		    b->report_size == 8) {
271 			features->quirks |= WACOM_QUIRK_AESPEN;
272 			usage->hid = WACOM_HID_WD_TOOLTYPE;
273 			field->logical_minimum = S16_MIN;
274 			field->logical_maximum = S16_MAX;
275 			a->logical_minimum = S32_MIN;
276 			a->logical_maximum = S32_MAX;
277 			b->usage[0].hid = WACOM_HID_WD_SERIALHI;
278 			b->logical_minimum = 0;
279 			b->logical_maximum = U8_MAX;
280 		}
281 	}
282 
283 	/* 2nd-generation Intuos Pro Large has incorrect Y maximum */
284 	if (hdev->vendor == USB_VENDOR_ID_WACOM &&
285 	    hdev->product == 0x0358 &&
286 	    WACOM_PEN_FIELD(field) &&
287 	    equivalent_usage == HID_GD_Y) {
288 		field->logical_maximum = 43200;
289 	}
290 }
291 
292 static void wacom_feature_mapping(struct hid_device *hdev,
293 		struct hid_field *field, struct hid_usage *usage)
294 {
295 	struct wacom *wacom = hid_get_drvdata(hdev);
296 	struct wacom_features *features = &wacom->wacom_wac.features;
297 	struct hid_data *hid_data = &wacom->wacom_wac.hid_data;
298 	unsigned int equivalent_usage = wacom_equivalent_usage(usage->hid);
299 	u8 *data;
300 	int ret;
301 	u32 n;
302 
303 	wacom_hid_usage_quirk(hdev, field, usage);
304 
305 	switch (equivalent_usage) {
306 	case WACOM_HID_WD_TOUCH_RING_SETTING:
307 		wacom->generic_has_leds = true;
308 		break;
309 	case HID_DG_CONTACTMAX:
310 		/* leave touch_max as is if predefined */
311 		if (!features->touch_max) {
312 			/* read manually */
313 			n = hid_report_len(field->report);
314 			data = hid_alloc_report_buf(field->report, GFP_KERNEL);
315 			if (!data)
316 				break;
317 			data[0] = field->report->id;
318 			ret = wacom_get_report(hdev, HID_FEATURE_REPORT,
319 					       data, n, WAC_CMD_RETRIES);
320 			if (ret == n && features->type == HID_GENERIC) {
321 				ret = hid_report_raw_event(hdev,
322 					HID_FEATURE_REPORT, data, n, 0);
323 			} else if (ret == 2 && features->type != HID_GENERIC) {
324 				features->touch_max = data[1];
325 			} else {
326 				features->touch_max = 16;
327 				hid_warn(hdev, "wacom_feature_mapping: "
328 					 "could not get HID_DG_CONTACTMAX, "
329 					 "defaulting to %d\n",
330 					  features->touch_max);
331 			}
332 			kfree(data);
333 		}
334 		break;
335 	case HID_DG_INPUTMODE:
336 		/* Ignore if value index is out of bounds. */
337 		if (usage->usage_index >= field->report_count) {
338 			dev_err(&hdev->dev, "HID_DG_INPUTMODE out of range\n");
339 			break;
340 		}
341 
342 		hid_data->inputmode = field->report->id;
343 		hid_data->inputmode_index = usage->usage_index;
344 		break;
345 
346 	case HID_UP_DIGITIZER:
347 		if (field->report->id == 0x0B &&
348 		    (field->application == WACOM_HID_G9_PEN ||
349 		     field->application == WACOM_HID_G11_PEN)) {
350 			wacom->wacom_wac.mode_report = field->report->id;
351 			wacom->wacom_wac.mode_value = 0;
352 		}
353 		break;
354 
355 	case WACOM_HID_WD_DATAMODE:
356 		wacom->wacom_wac.mode_report = field->report->id;
357 		wacom->wacom_wac.mode_value = 2;
358 		break;
359 
360 	case WACOM_HID_UP_G9:
361 	case WACOM_HID_UP_G11:
362 		if (field->report->id == 0x03 &&
363 		    (field->application == WACOM_HID_G9_TOUCHSCREEN ||
364 		     field->application == WACOM_HID_G11_TOUCHSCREEN)) {
365 			wacom->wacom_wac.mode_report = field->report->id;
366 			wacom->wacom_wac.mode_value = 0;
367 		}
368 		break;
369 	case WACOM_HID_WD_OFFSETLEFT:
370 	case WACOM_HID_WD_OFFSETTOP:
371 	case WACOM_HID_WD_OFFSETRIGHT:
372 	case WACOM_HID_WD_OFFSETBOTTOM:
373 		/* read manually */
374 		n = hid_report_len(field->report);
375 		data = hid_alloc_report_buf(field->report, GFP_KERNEL);
376 		if (!data)
377 			break;
378 		data[0] = field->report->id;
379 		ret = wacom_get_report(hdev, HID_FEATURE_REPORT,
380 					data, n, WAC_CMD_RETRIES);
381 		if (ret == n) {
382 			ret = hid_report_raw_event(hdev, HID_FEATURE_REPORT,
383 						   data, n, 0);
384 		} else {
385 			hid_warn(hdev, "%s: could not retrieve sensor offsets\n",
386 				 __func__);
387 		}
388 		kfree(data);
389 		break;
390 	}
391 }
392 
393 /*
394  * Interface Descriptor of wacom devices can be incomplete and
395  * inconsistent so wacom_features table is used to store stylus
396  * device's packet lengths, various maximum values, and tablet
397  * resolution based on product ID's.
398  *
399  * For devices that contain 2 interfaces, wacom_features table is
400  * inaccurate for the touch interface.  Since the Interface Descriptor
401  * for touch interfaces has pretty complete data, this function exists
402  * to query tablet for this missing information instead of hard coding in
403  * an additional table.
404  *
405  * A typical Interface Descriptor for a stylus will contain a
406  * boot mouse application collection that is not of interest and this
407  * function will ignore it.
408  *
409  * It also contains a digitizer application collection that also is not
410  * of interest since any information it contains would be duplicate
411  * of what is in wacom_features. Usually it defines a report of an array
412  * of bytes that could be used as max length of the stylus packet returned.
413  * If it happens to define a Digitizer-Stylus Physical Collection then
414  * the X and Y logical values contain valid data but it is ignored.
415  *
416  * A typical Interface Descriptor for a touch interface will contain a
417  * Digitizer-Finger Physical Collection which will define both logical
418  * X/Y maximum as well as the physical size of tablet. Since touch
419  * interfaces haven't supported pressure or distance, this is enough
420  * information to override invalid values in the wacom_features table.
421  *
422  * Intuos5 touch interface and 3rd gen Bamboo Touch do not contain useful
423  * data. We deal with them after returning from this function.
424  */
425 static void wacom_usage_mapping(struct hid_device *hdev,
426 		struct hid_field *field, struct hid_usage *usage)
427 {
428 	struct wacom *wacom = hid_get_drvdata(hdev);
429 	struct wacom_features *features = &wacom->wacom_wac.features;
430 	bool finger = WACOM_FINGER_FIELD(field);
431 	bool pen = WACOM_PEN_FIELD(field);
432 	unsigned equivalent_usage = wacom_equivalent_usage(usage->hid);
433 
434 	/*
435 	* Requiring Stylus Usage will ignore boot mouse
436 	* X/Y values and some cases of invalid Digitizer X/Y
437 	* values commonly reported.
438 	*/
439 	if (pen)
440 		features->device_type |= WACOM_DEVICETYPE_PEN;
441 	else if (finger)
442 		features->device_type |= WACOM_DEVICETYPE_TOUCH;
443 	else
444 		return;
445 
446 	wacom_hid_usage_quirk(hdev, field, usage);
447 
448 	switch (equivalent_usage) {
449 	case HID_GD_X:
450 		features->x_max = field->logical_maximum;
451 		if (finger) {
452 			features->x_phy = field->physical_maximum;
453 			if ((features->type != BAMBOO_PT) &&
454 			    (features->type != BAMBOO_TOUCH)) {
455 				features->unit = field->unit;
456 				features->unitExpo = field->unit_exponent;
457 			}
458 		}
459 		break;
460 	case HID_GD_Y:
461 		features->y_max = field->logical_maximum;
462 		if (finger) {
463 			features->y_phy = field->physical_maximum;
464 			if ((features->type != BAMBOO_PT) &&
465 			    (features->type != BAMBOO_TOUCH)) {
466 				features->unit = field->unit;
467 				features->unitExpo = field->unit_exponent;
468 			}
469 		}
470 		break;
471 	case HID_DG_TIPPRESSURE:
472 		if (pen)
473 			features->pressure_max = field->logical_maximum;
474 		break;
475 	}
476 
477 	if (features->type == HID_GENERIC)
478 		wacom_wac_usage_mapping(hdev, field, usage);
479 }
480 
481 static void wacom_post_parse_hid(struct hid_device *hdev,
482 				 struct wacom_features *features)
483 {
484 	struct wacom *wacom = hid_get_drvdata(hdev);
485 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
486 
487 	if (features->type == HID_GENERIC) {
488 		/* Any last-minute generic device setup */
489 		if (wacom_wac->has_mode_change) {
490 			if (wacom_wac->is_direct_mode)
491 				features->device_type |= WACOM_DEVICETYPE_DIRECT;
492 			else
493 				features->device_type &= ~WACOM_DEVICETYPE_DIRECT;
494 		}
495 
496 		if (features->touch_max > 1) {
497 			if (features->device_type & WACOM_DEVICETYPE_DIRECT)
498 				input_mt_init_slots(wacom_wac->touch_input,
499 						    wacom_wac->features.touch_max,
500 						    INPUT_MT_DIRECT);
501 			else
502 				input_mt_init_slots(wacom_wac->touch_input,
503 						    wacom_wac->features.touch_max,
504 						    INPUT_MT_POINTER);
505 		}
506 	}
507 }
508 
509 static void wacom_parse_hid(struct hid_device *hdev,
510 			   struct wacom_features *features)
511 {
512 	struct hid_report_enum *rep_enum;
513 	struct hid_report *hreport;
514 	int i, j;
515 
516 	/* check features first */
517 	rep_enum = &hdev->report_enum[HID_FEATURE_REPORT];
518 	list_for_each_entry(hreport, &rep_enum->report_list, list) {
519 		for (i = 0; i < hreport->maxfield; i++) {
520 			/* Ignore if report count is out of bounds. */
521 			if (hreport->field[i]->report_count < 1)
522 				continue;
523 
524 			for (j = 0; j < hreport->field[i]->maxusage; j++) {
525 				wacom_feature_mapping(hdev, hreport->field[i],
526 						hreport->field[i]->usage + j);
527 			}
528 		}
529 	}
530 
531 	/* now check the input usages */
532 	rep_enum = &hdev->report_enum[HID_INPUT_REPORT];
533 	list_for_each_entry(hreport, &rep_enum->report_list, list) {
534 
535 		if (!hreport->maxfield)
536 			continue;
537 
538 		for (i = 0; i < hreport->maxfield; i++)
539 			for (j = 0; j < hreport->field[i]->maxusage; j++)
540 				wacom_usage_mapping(hdev, hreport->field[i],
541 						hreport->field[i]->usage + j);
542 	}
543 
544 	wacom_post_parse_hid(hdev, features);
545 }
546 
547 static int wacom_hid_set_device_mode(struct hid_device *hdev)
548 {
549 	struct wacom *wacom = hid_get_drvdata(hdev);
550 	struct hid_data *hid_data = &wacom->wacom_wac.hid_data;
551 	struct hid_report *r;
552 	struct hid_report_enum *re;
553 
554 	if (hid_data->inputmode < 0)
555 		return 0;
556 
557 	re = &(hdev->report_enum[HID_FEATURE_REPORT]);
558 	r = re->report_id_hash[hid_data->inputmode];
559 	if (r) {
560 		r->field[0]->value[hid_data->inputmode_index] = 2;
561 		hid_hw_request(hdev, r, HID_REQ_SET_REPORT);
562 	}
563 	return 0;
564 }
565 
566 static int wacom_set_device_mode(struct hid_device *hdev,
567 				 struct wacom_wac *wacom_wac)
568 {
569 	u8 *rep_data;
570 	struct hid_report *r;
571 	struct hid_report_enum *re;
572 	u32 length;
573 	int error = -ENOMEM, limit = 0;
574 
575 	if (wacom_wac->mode_report < 0)
576 		return 0;
577 
578 	re = &(hdev->report_enum[HID_FEATURE_REPORT]);
579 	r = re->report_id_hash[wacom_wac->mode_report];
580 	if (!r)
581 		return -EINVAL;
582 
583 	rep_data = hid_alloc_report_buf(r, GFP_KERNEL);
584 	if (!rep_data)
585 		return -ENOMEM;
586 
587 	length = hid_report_len(r);
588 
589 	do {
590 		rep_data[0] = wacom_wac->mode_report;
591 		rep_data[1] = wacom_wac->mode_value;
592 
593 		error = wacom_set_report(hdev, HID_FEATURE_REPORT, rep_data,
594 					 length, 1);
595 		if (error >= 0)
596 			error = wacom_get_report(hdev, HID_FEATURE_REPORT,
597 			                         rep_data, length, 1);
598 	} while (error >= 0 &&
599 		 rep_data[1] != wacom_wac->mode_report &&
600 		 limit++ < WAC_MSG_RETRIES);
601 
602 	kfree(rep_data);
603 
604 	return error < 0 ? error : 0;
605 }
606 
607 static int wacom_bt_query_tablet_data(struct hid_device *hdev, u8 speed,
608 		struct wacom_features *features)
609 {
610 	struct wacom *wacom = hid_get_drvdata(hdev);
611 	int ret;
612 	u8 rep_data[2];
613 
614 	switch (features->type) {
615 	case GRAPHIRE_BT:
616 		rep_data[0] = 0x03;
617 		rep_data[1] = 0x00;
618 		ret = wacom_set_report(hdev, HID_FEATURE_REPORT, rep_data, 2,
619 					3);
620 
621 		if (ret >= 0) {
622 			rep_data[0] = speed == 0 ? 0x05 : 0x06;
623 			rep_data[1] = 0x00;
624 
625 			ret = wacom_set_report(hdev, HID_FEATURE_REPORT,
626 						rep_data, 2, 3);
627 
628 			if (ret >= 0) {
629 				wacom->wacom_wac.bt_high_speed = speed;
630 				return 0;
631 			}
632 		}
633 
634 		/*
635 		 * Note that if the raw queries fail, it's not a hard failure
636 		 * and it is safe to continue
637 		 */
638 		hid_warn(hdev, "failed to poke device, command %d, err %d\n",
639 			 rep_data[0], ret);
640 		break;
641 	case INTUOS4WL:
642 		if (speed == 1)
643 			wacom->wacom_wac.bt_features &= ~0x20;
644 		else
645 			wacom->wacom_wac.bt_features |= 0x20;
646 
647 		rep_data[0] = 0x03;
648 		rep_data[1] = wacom->wacom_wac.bt_features;
649 
650 		ret = wacom_set_report(hdev, HID_FEATURE_REPORT, rep_data, 2,
651 					1);
652 		if (ret >= 0)
653 			wacom->wacom_wac.bt_high_speed = speed;
654 		break;
655 	}
656 
657 	return 0;
658 }
659 
660 /*
661  * Switch the tablet into its most-capable mode. Wacom tablets are
662  * typically configured to power-up in a mode which sends mouse-like
663  * reports to the OS. To get absolute position, pressure data, etc.
664  * from the tablet, it is necessary to switch the tablet out of this
665  * mode and into one which sends the full range of tablet data.
666  */
667 static int _wacom_query_tablet_data(struct wacom *wacom)
668 {
669 	struct hid_device *hdev = wacom->hdev;
670 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
671 	struct wacom_features *features = &wacom_wac->features;
672 
673 	if (hdev->bus == BUS_BLUETOOTH)
674 		return wacom_bt_query_tablet_data(hdev, 1, features);
675 
676 	if (features->type != HID_GENERIC) {
677 		if (features->device_type & WACOM_DEVICETYPE_TOUCH) {
678 			if (features->type > TABLETPC) {
679 				/* MT Tablet PC touch */
680 				wacom_wac->mode_report = 3;
681 				wacom_wac->mode_value = 4;
682 			} else if (features->type == WACOM_24HDT) {
683 				wacom_wac->mode_report = 18;
684 				wacom_wac->mode_value = 2;
685 			} else if (features->type == WACOM_27QHDT) {
686 				wacom_wac->mode_report = 131;
687 				wacom_wac->mode_value = 2;
688 			} else if (features->type == BAMBOO_PAD) {
689 				wacom_wac->mode_report = 2;
690 				wacom_wac->mode_value = 2;
691 			}
692 		} else if (features->device_type & WACOM_DEVICETYPE_PEN) {
693 			if (features->type <= BAMBOO_PT) {
694 				wacom_wac->mode_report = 2;
695 				wacom_wac->mode_value = 2;
696 			}
697 		}
698 	}
699 
700 	wacom_set_device_mode(hdev, wacom_wac);
701 
702 	if (features->type == HID_GENERIC)
703 		return wacom_hid_set_device_mode(hdev);
704 
705 	return 0;
706 }
707 
708 static void wacom_retrieve_hid_descriptor(struct hid_device *hdev,
709 					 struct wacom_features *features)
710 {
711 	struct wacom *wacom = hid_get_drvdata(hdev);
712 	struct usb_interface *intf = wacom->intf;
713 
714 	/* default features */
715 	features->x_fuzz = 4;
716 	features->y_fuzz = 4;
717 	features->pressure_fuzz = 0;
718 	features->distance_fuzz = 1;
719 	features->tilt_fuzz = 1;
720 
721 	/*
722 	 * The wireless device HID is basic and layout conflicts with
723 	 * other tablets (monitor and touch interface can look like pen).
724 	 * Skip the query for this type and modify defaults based on
725 	 * interface number.
726 	 */
727 	if (features->type == WIRELESS && intf) {
728 		if (intf->cur_altsetting->desc.bInterfaceNumber == 0)
729 			features->device_type = WACOM_DEVICETYPE_WL_MONITOR;
730 		else
731 			features->device_type = WACOM_DEVICETYPE_NONE;
732 		return;
733 	}
734 
735 	wacom_parse_hid(hdev, features);
736 }
737 
738 struct wacom_hdev_data {
739 	struct list_head list;
740 	struct kref kref;
741 	struct hid_device *dev;
742 	struct wacom_shared shared;
743 };
744 
745 static LIST_HEAD(wacom_udev_list);
746 static DEFINE_MUTEX(wacom_udev_list_lock);
747 
748 static bool wacom_are_sibling(struct hid_device *hdev,
749 		struct hid_device *sibling)
750 {
751 	struct wacom *wacom = hid_get_drvdata(hdev);
752 	struct wacom_features *features = &wacom->wacom_wac.features;
753 	struct wacom *sibling_wacom = hid_get_drvdata(sibling);
754 	struct wacom_features *sibling_features = &sibling_wacom->wacom_wac.features;
755 	__u32 oVid = features->oVid ? features->oVid : hdev->vendor;
756 	__u32 oPid = features->oPid ? features->oPid : hdev->product;
757 
758 	/* The defined oVid/oPid must match that of the sibling */
759 	if (features->oVid != HID_ANY_ID && sibling->vendor != oVid)
760 		return false;
761 	if (features->oPid != HID_ANY_ID && sibling->product != oPid)
762 		return false;
763 
764 	/*
765 	 * Devices with the same VID/PID must share the same physical
766 	 * device path, while those with different VID/PID must share
767 	 * the same physical parent device path.
768 	 */
769 	if (hdev->vendor == sibling->vendor && hdev->product == sibling->product) {
770 		if (!hid_compare_device_paths(hdev, sibling, '/'))
771 			return false;
772 	} else {
773 		if (!hid_compare_device_paths(hdev, sibling, '.'))
774 			return false;
775 	}
776 
777 	/* Skip the remaining heuristics unless you are a HID_GENERIC device */
778 	if (features->type != HID_GENERIC)
779 		return true;
780 
781 	/*
782 	 * Direct-input devices may not be siblings of indirect-input
783 	 * devices.
784 	 */
785 	if ((features->device_type & WACOM_DEVICETYPE_DIRECT) &&
786 	    !(sibling_features->device_type & WACOM_DEVICETYPE_DIRECT))
787 		return false;
788 
789 	/*
790 	 * Indirect-input devices may not be siblings of direct-input
791 	 * devices.
792 	 */
793 	if (!(features->device_type & WACOM_DEVICETYPE_DIRECT) &&
794 	    (sibling_features->device_type & WACOM_DEVICETYPE_DIRECT))
795 		return false;
796 
797 	/* Pen devices may only be siblings of touch devices */
798 	if ((features->device_type & WACOM_DEVICETYPE_PEN) &&
799 	    !(sibling_features->device_type & WACOM_DEVICETYPE_TOUCH))
800 		return false;
801 
802 	/* Touch devices may only be siblings of pen devices */
803 	if ((features->device_type & WACOM_DEVICETYPE_TOUCH) &&
804 	    !(sibling_features->device_type & WACOM_DEVICETYPE_PEN))
805 		return false;
806 
807 	/*
808 	 * No reason could be found for these two devices to NOT be
809 	 * siblings, so there's a good chance they ARE siblings
810 	 */
811 	return true;
812 }
813 
814 static struct wacom_hdev_data *wacom_get_hdev_data(struct hid_device *hdev)
815 {
816 	struct wacom_hdev_data *data;
817 
818 	/* Try to find an already-probed interface from the same device */
819 	list_for_each_entry(data, &wacom_udev_list, list) {
820 		if (hid_compare_device_paths(hdev, data->dev, '/')) {
821 			kref_get(&data->kref);
822 			return data;
823 		}
824 	}
825 
826 	/* Fallback to finding devices that appear to be "siblings" */
827 	list_for_each_entry(data, &wacom_udev_list, list) {
828 		if (wacom_are_sibling(hdev, data->dev)) {
829 			kref_get(&data->kref);
830 			return data;
831 		}
832 	}
833 
834 	return NULL;
835 }
836 
837 static void wacom_release_shared_data(struct kref *kref)
838 {
839 	struct wacom_hdev_data *data =
840 		container_of(kref, struct wacom_hdev_data, kref);
841 
842 	mutex_lock(&wacom_udev_list_lock);
843 	list_del(&data->list);
844 	mutex_unlock(&wacom_udev_list_lock);
845 
846 	kfree(data);
847 }
848 
849 static void wacom_remove_shared_data(void *res)
850 {
851 	struct wacom *wacom = res;
852 	struct wacom_hdev_data *data;
853 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
854 
855 	if (wacom_wac->shared) {
856 		data = container_of(wacom_wac->shared, struct wacom_hdev_data,
857 				    shared);
858 
859 		if (wacom_wac->shared->touch == wacom->hdev)
860 			wacom_wac->shared->touch = NULL;
861 		else if (wacom_wac->shared->pen == wacom->hdev)
862 			wacom_wac->shared->pen = NULL;
863 
864 		kref_put(&data->kref, wacom_release_shared_data);
865 		wacom_wac->shared = NULL;
866 	}
867 }
868 
869 static int wacom_add_shared_data(struct hid_device *hdev)
870 {
871 	struct wacom *wacom = hid_get_drvdata(hdev);
872 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
873 	struct wacom_hdev_data *data;
874 	int retval = 0;
875 
876 	mutex_lock(&wacom_udev_list_lock);
877 
878 	data = wacom_get_hdev_data(hdev);
879 	if (!data) {
880 		data = kzalloc(sizeof(struct wacom_hdev_data), GFP_KERNEL);
881 		if (!data) {
882 			mutex_unlock(&wacom_udev_list_lock);
883 			return -ENOMEM;
884 		}
885 
886 		kref_init(&data->kref);
887 		data->dev = hdev;
888 		list_add_tail(&data->list, &wacom_udev_list);
889 	}
890 
891 	mutex_unlock(&wacom_udev_list_lock);
892 
893 	wacom_wac->shared = &data->shared;
894 
895 	retval = devm_add_action_or_reset(&hdev->dev, wacom_remove_shared_data, wacom);
896 	if (retval)
897 		return retval;
898 
899 	if (wacom_wac->features.device_type & WACOM_DEVICETYPE_TOUCH)
900 		wacom_wac->shared->touch = hdev;
901 	else if (wacom_wac->features.device_type & WACOM_DEVICETYPE_PEN)
902 		wacom_wac->shared->pen = hdev;
903 
904 	return retval;
905 }
906 
907 static int wacom_led_control(struct wacom *wacom)
908 {
909 	unsigned char *buf;
910 	int retval;
911 	unsigned char report_id = WAC_CMD_LED_CONTROL;
912 	int buf_size = 9;
913 
914 	if (!wacom->led.groups)
915 		return -ENOTSUPP;
916 
917 	if (wacom->wacom_wac.features.type == REMOTE)
918 		return -ENOTSUPP;
919 
920 	if (wacom->wacom_wac.pid) { /* wireless connected */
921 		report_id = WAC_CMD_WL_LED_CONTROL;
922 		buf_size = 13;
923 	}
924 	else if (wacom->wacom_wac.features.type == INTUOSP2_BT) {
925 		report_id = WAC_CMD_WL_INTUOSP2;
926 		buf_size = 51;
927 	}
928 	buf = kzalloc(buf_size, GFP_KERNEL);
929 	if (!buf)
930 		return -ENOMEM;
931 
932 	if (wacom->wacom_wac.features.type == HID_GENERIC) {
933 		buf[0] = WAC_CMD_LED_CONTROL_GENERIC;
934 		buf[1] = wacom->led.llv;
935 		buf[2] = wacom->led.groups[0].select & 0x03;
936 
937 	} else if ((wacom->wacom_wac.features.type >= INTUOS5S &&
938 	    wacom->wacom_wac.features.type <= INTUOSPL)) {
939 		/*
940 		 * Touch Ring and crop mark LED luminance may take on
941 		 * one of four values:
942 		 *    0 = Low; 1 = Medium; 2 = High; 3 = Off
943 		 */
944 		int ring_led = wacom->led.groups[0].select & 0x03;
945 		int ring_lum = (((wacom->led.llv & 0x60) >> 5) - 1) & 0x03;
946 		int crop_lum = 0;
947 		unsigned char led_bits = (crop_lum << 4) | (ring_lum << 2) | (ring_led);
948 
949 		buf[0] = report_id;
950 		if (wacom->wacom_wac.pid) {
951 			wacom_get_report(wacom->hdev, HID_FEATURE_REPORT,
952 					 buf, buf_size, WAC_CMD_RETRIES);
953 			buf[0] = report_id;
954 			buf[4] = led_bits;
955 		} else
956 			buf[1] = led_bits;
957 	}
958 	else if (wacom->wacom_wac.features.type == INTUOSP2_BT) {
959 		buf[0] = report_id;
960 		buf[4] = 100; // Power Connection LED (ORANGE)
961 		buf[5] = 100; // BT Connection LED (BLUE)
962 		buf[6] = 100; // Paper Mode (RED?)
963 		buf[7] = 100; // Paper Mode (GREEN?)
964 		buf[8] = 100; // Paper Mode (BLUE?)
965 		buf[9] = wacom->led.llv;
966 		buf[10] = wacom->led.groups[0].select & 0x03;
967 	}
968 	else {
969 		int led = wacom->led.groups[0].select | 0x4;
970 
971 		if (wacom->wacom_wac.features.type == WACOM_21UX2 ||
972 		    wacom->wacom_wac.features.type == WACOM_24HD)
973 			led |= (wacom->led.groups[1].select << 4) | 0x40;
974 
975 		buf[0] = report_id;
976 		buf[1] = led;
977 		buf[2] = wacom->led.llv;
978 		buf[3] = wacom->led.hlv;
979 		buf[4] = wacom->led.img_lum;
980 	}
981 
982 	retval = wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, buf_size,
983 				  WAC_CMD_RETRIES);
984 	kfree(buf);
985 
986 	return retval;
987 }
988 
989 static int wacom_led_putimage(struct wacom *wacom, int button_id, u8 xfer_id,
990 		const unsigned len, const void *img)
991 {
992 	unsigned char *buf;
993 	int i, retval;
994 	const unsigned chunk_len = len / 4; /* 4 chunks are needed to be sent */
995 
996 	buf = kzalloc(chunk_len + 3 , GFP_KERNEL);
997 	if (!buf)
998 		return -ENOMEM;
999 
1000 	/* Send 'start' command */
1001 	buf[0] = WAC_CMD_ICON_START;
1002 	buf[1] = 1;
1003 	retval = wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, 2,
1004 				  WAC_CMD_RETRIES);
1005 	if (retval < 0)
1006 		goto out;
1007 
1008 	buf[0] = xfer_id;
1009 	buf[1] = button_id & 0x07;
1010 	for (i = 0; i < 4; i++) {
1011 		buf[2] = i;
1012 		memcpy(buf + 3, img + i * chunk_len, chunk_len);
1013 
1014 		retval = wacom_set_report(wacom->hdev, HID_FEATURE_REPORT,
1015 					  buf, chunk_len + 3, WAC_CMD_RETRIES);
1016 		if (retval < 0)
1017 			break;
1018 	}
1019 
1020 	/* Send 'stop' */
1021 	buf[0] = WAC_CMD_ICON_START;
1022 	buf[1] = 0;
1023 	wacom_set_report(wacom->hdev, HID_FEATURE_REPORT, buf, 2,
1024 			 WAC_CMD_RETRIES);
1025 
1026 out:
1027 	kfree(buf);
1028 	return retval;
1029 }
1030 
1031 static ssize_t wacom_led_select_store(struct device *dev, int set_id,
1032 				      const char *buf, size_t count)
1033 {
1034 	struct hid_device *hdev = to_hid_device(dev);
1035 	struct wacom *wacom = hid_get_drvdata(hdev);
1036 	unsigned int id;
1037 	int err;
1038 
1039 	err = kstrtouint(buf, 10, &id);
1040 	if (err)
1041 		return err;
1042 
1043 	mutex_lock(&wacom->lock);
1044 
1045 	wacom->led.groups[set_id].select = id & 0x3;
1046 	err = wacom_led_control(wacom);
1047 
1048 	mutex_unlock(&wacom->lock);
1049 
1050 	return err < 0 ? err : count;
1051 }
1052 
1053 #define DEVICE_LED_SELECT_ATTR(SET_ID)					\
1054 static ssize_t wacom_led##SET_ID##_select_store(struct device *dev,	\
1055 	struct device_attribute *attr, const char *buf, size_t count)	\
1056 {									\
1057 	return wacom_led_select_store(dev, SET_ID, buf, count);		\
1058 }									\
1059 static ssize_t wacom_led##SET_ID##_select_show(struct device *dev,	\
1060 	struct device_attribute *attr, char *buf)			\
1061 {									\
1062 	struct hid_device *hdev = to_hid_device(dev);\
1063 	struct wacom *wacom = hid_get_drvdata(hdev);			\
1064 	return scnprintf(buf, PAGE_SIZE, "%d\n",			\
1065 			 wacom->led.groups[SET_ID].select);		\
1066 }									\
1067 static DEVICE_ATTR(status_led##SET_ID##_select, DEV_ATTR_RW_PERM,	\
1068 		    wacom_led##SET_ID##_select_show,			\
1069 		    wacom_led##SET_ID##_select_store)
1070 
1071 DEVICE_LED_SELECT_ATTR(0);
1072 DEVICE_LED_SELECT_ATTR(1);
1073 
1074 static ssize_t wacom_luminance_store(struct wacom *wacom, u8 *dest,
1075 				     const char *buf, size_t count)
1076 {
1077 	unsigned int value;
1078 	int err;
1079 
1080 	err = kstrtouint(buf, 10, &value);
1081 	if (err)
1082 		return err;
1083 
1084 	mutex_lock(&wacom->lock);
1085 
1086 	*dest = value & 0x7f;
1087 	err = wacom_led_control(wacom);
1088 
1089 	mutex_unlock(&wacom->lock);
1090 
1091 	return err < 0 ? err : count;
1092 }
1093 
1094 #define DEVICE_LUMINANCE_ATTR(name, field)				\
1095 static ssize_t wacom_##name##_luminance_store(struct device *dev,	\
1096 	struct device_attribute *attr, const char *buf, size_t count)	\
1097 {									\
1098 	struct hid_device *hdev = to_hid_device(dev);\
1099 	struct wacom *wacom = hid_get_drvdata(hdev);			\
1100 									\
1101 	return wacom_luminance_store(wacom, &wacom->led.field,		\
1102 				     buf, count);			\
1103 }									\
1104 static ssize_t wacom_##name##_luminance_show(struct device *dev,	\
1105 	struct device_attribute *attr, char *buf)			\
1106 {									\
1107 	struct wacom *wacom = dev_get_drvdata(dev);			\
1108 	return scnprintf(buf, PAGE_SIZE, "%d\n", wacom->led.field);	\
1109 }									\
1110 static DEVICE_ATTR(name##_luminance, DEV_ATTR_RW_PERM,			\
1111 		   wacom_##name##_luminance_show,			\
1112 		   wacom_##name##_luminance_store)
1113 
1114 DEVICE_LUMINANCE_ATTR(status0, llv);
1115 DEVICE_LUMINANCE_ATTR(status1, hlv);
1116 DEVICE_LUMINANCE_ATTR(buttons, img_lum);
1117 
1118 static ssize_t wacom_button_image_store(struct device *dev, int button_id,
1119 					const char *buf, size_t count)
1120 {
1121 	struct hid_device *hdev = to_hid_device(dev);
1122 	struct wacom *wacom = hid_get_drvdata(hdev);
1123 	int err;
1124 	unsigned len;
1125 	u8 xfer_id;
1126 
1127 	if (hdev->bus == BUS_BLUETOOTH) {
1128 		len = 256;
1129 		xfer_id = WAC_CMD_ICON_BT_XFER;
1130 	} else {
1131 		len = 1024;
1132 		xfer_id = WAC_CMD_ICON_XFER;
1133 	}
1134 
1135 	if (count != len)
1136 		return -EINVAL;
1137 
1138 	mutex_lock(&wacom->lock);
1139 
1140 	err = wacom_led_putimage(wacom, button_id, xfer_id, len, buf);
1141 
1142 	mutex_unlock(&wacom->lock);
1143 
1144 	return err < 0 ? err : count;
1145 }
1146 
1147 #define DEVICE_BTNIMG_ATTR(BUTTON_ID)					\
1148 static ssize_t wacom_btnimg##BUTTON_ID##_store(struct device *dev,	\
1149 	struct device_attribute *attr, const char *buf, size_t count)	\
1150 {									\
1151 	return wacom_button_image_store(dev, BUTTON_ID, buf, count);	\
1152 }									\
1153 static DEVICE_ATTR(button##BUTTON_ID##_rawimg, DEV_ATTR_WO_PERM,	\
1154 		   NULL, wacom_btnimg##BUTTON_ID##_store)
1155 
1156 DEVICE_BTNIMG_ATTR(0);
1157 DEVICE_BTNIMG_ATTR(1);
1158 DEVICE_BTNIMG_ATTR(2);
1159 DEVICE_BTNIMG_ATTR(3);
1160 DEVICE_BTNIMG_ATTR(4);
1161 DEVICE_BTNIMG_ATTR(5);
1162 DEVICE_BTNIMG_ATTR(6);
1163 DEVICE_BTNIMG_ATTR(7);
1164 
1165 static struct attribute *cintiq_led_attrs[] = {
1166 	&dev_attr_status_led0_select.attr,
1167 	&dev_attr_status_led1_select.attr,
1168 	NULL
1169 };
1170 
1171 static const struct attribute_group cintiq_led_attr_group = {
1172 	.name = "wacom_led",
1173 	.attrs = cintiq_led_attrs,
1174 };
1175 
1176 static struct attribute *intuos4_led_attrs[] = {
1177 	&dev_attr_status0_luminance.attr,
1178 	&dev_attr_status1_luminance.attr,
1179 	&dev_attr_status_led0_select.attr,
1180 	&dev_attr_buttons_luminance.attr,
1181 	&dev_attr_button0_rawimg.attr,
1182 	&dev_attr_button1_rawimg.attr,
1183 	&dev_attr_button2_rawimg.attr,
1184 	&dev_attr_button3_rawimg.attr,
1185 	&dev_attr_button4_rawimg.attr,
1186 	&dev_attr_button5_rawimg.attr,
1187 	&dev_attr_button6_rawimg.attr,
1188 	&dev_attr_button7_rawimg.attr,
1189 	NULL
1190 };
1191 
1192 static const struct attribute_group intuos4_led_attr_group = {
1193 	.name = "wacom_led",
1194 	.attrs = intuos4_led_attrs,
1195 };
1196 
1197 static struct attribute *intuos5_led_attrs[] = {
1198 	&dev_attr_status0_luminance.attr,
1199 	&dev_attr_status_led0_select.attr,
1200 	NULL
1201 };
1202 
1203 static const struct attribute_group intuos5_led_attr_group = {
1204 	.name = "wacom_led",
1205 	.attrs = intuos5_led_attrs,
1206 };
1207 
1208 static struct attribute *generic_led_attrs[] = {
1209 	&dev_attr_status0_luminance.attr,
1210 	&dev_attr_status_led0_select.attr,
1211 	NULL
1212 };
1213 
1214 static const struct attribute_group generic_led_attr_group = {
1215 	.name = "wacom_led",
1216 	.attrs = generic_led_attrs,
1217 };
1218 
1219 struct wacom_sysfs_group_devres {
1220 	const struct attribute_group *group;
1221 	struct kobject *root;
1222 };
1223 
1224 static void wacom_devm_sysfs_group_release(struct device *dev, void *res)
1225 {
1226 	struct wacom_sysfs_group_devres *devres = res;
1227 	struct kobject *kobj = devres->root;
1228 
1229 	dev_dbg(dev, "%s: dropping reference to %s\n",
1230 		__func__, devres->group->name);
1231 	sysfs_remove_group(kobj, devres->group);
1232 }
1233 
1234 static int __wacom_devm_sysfs_create_group(struct wacom *wacom,
1235 					   struct kobject *root,
1236 					   const struct attribute_group *group)
1237 {
1238 	struct wacom_sysfs_group_devres *devres;
1239 	int error;
1240 
1241 	devres = devres_alloc(wacom_devm_sysfs_group_release,
1242 			      sizeof(struct wacom_sysfs_group_devres),
1243 			      GFP_KERNEL);
1244 	if (!devres)
1245 		return -ENOMEM;
1246 
1247 	devres->group = group;
1248 	devres->root = root;
1249 
1250 	error = sysfs_create_group(devres->root, group);
1251 	if (error) {
1252 		devres_free(devres);
1253 		return error;
1254 	}
1255 
1256 	devres_add(&wacom->hdev->dev, devres);
1257 
1258 	return 0;
1259 }
1260 
1261 static int wacom_devm_sysfs_create_group(struct wacom *wacom,
1262 					 const struct attribute_group *group)
1263 {
1264 	return __wacom_devm_sysfs_create_group(wacom, &wacom->hdev->dev.kobj,
1265 					       group);
1266 }
1267 
1268 static void wacom_devm_kfifo_release(struct device *dev, void *res)
1269 {
1270 	struct kfifo_rec_ptr_2 *devres = res;
1271 
1272 	kfifo_free(devres);
1273 }
1274 
1275 static int wacom_devm_kfifo_alloc(struct wacom *wacom)
1276 {
1277 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
1278 	struct kfifo_rec_ptr_2 *pen_fifo;
1279 	int error;
1280 
1281 	pen_fifo = devres_alloc(wacom_devm_kfifo_release,
1282 			      sizeof(struct kfifo_rec_ptr_2),
1283 			      GFP_KERNEL);
1284 
1285 	if (!pen_fifo)
1286 		return -ENOMEM;
1287 
1288 	error = kfifo_alloc(pen_fifo, WACOM_PKGLEN_MAX, GFP_KERNEL);
1289 	if (error) {
1290 		devres_free(pen_fifo);
1291 		return error;
1292 	}
1293 
1294 	devres_add(&wacom->hdev->dev, pen_fifo);
1295 	wacom_wac->pen_fifo = pen_fifo;
1296 
1297 	return 0;
1298 }
1299 
1300 enum led_brightness wacom_leds_brightness_get(struct wacom_led *led)
1301 {
1302 	struct wacom *wacom = led->wacom;
1303 
1304 	if (wacom->led.max_hlv)
1305 		return led->hlv * LED_FULL / wacom->led.max_hlv;
1306 
1307 	if (wacom->led.max_llv)
1308 		return led->llv * LED_FULL / wacom->led.max_llv;
1309 
1310 	/* device doesn't support brightness tuning */
1311 	return LED_FULL;
1312 }
1313 
1314 static enum led_brightness __wacom_led_brightness_get(struct led_classdev *cdev)
1315 {
1316 	struct wacom_led *led = container_of(cdev, struct wacom_led, cdev);
1317 	struct wacom *wacom = led->wacom;
1318 
1319 	if (wacom->led.groups[led->group].select != led->id)
1320 		return LED_OFF;
1321 
1322 	return wacom_leds_brightness_get(led);
1323 }
1324 
1325 static int wacom_led_brightness_set(struct led_classdev *cdev,
1326 				    enum led_brightness brightness)
1327 {
1328 	struct wacom_led *led = container_of(cdev, struct wacom_led, cdev);
1329 	struct wacom *wacom = led->wacom;
1330 	int error;
1331 
1332 	mutex_lock(&wacom->lock);
1333 
1334 	if (!wacom->led.groups || (brightness == LED_OFF &&
1335 	    wacom->led.groups[led->group].select != led->id)) {
1336 		error = 0;
1337 		goto out;
1338 	}
1339 
1340 	led->llv = wacom->led.llv = wacom->led.max_llv * brightness / LED_FULL;
1341 	led->hlv = wacom->led.hlv = wacom->led.max_hlv * brightness / LED_FULL;
1342 
1343 	wacom->led.groups[led->group].select = led->id;
1344 
1345 	error = wacom_led_control(wacom);
1346 
1347 out:
1348 	mutex_unlock(&wacom->lock);
1349 
1350 	return error;
1351 }
1352 
1353 static void wacom_led_readonly_brightness_set(struct led_classdev *cdev,
1354 					       enum led_brightness brightness)
1355 {
1356 }
1357 
1358 static int wacom_led_register_one(struct device *dev, struct wacom *wacom,
1359 				  struct wacom_led *led, unsigned int group,
1360 				  unsigned int id, bool read_only)
1361 {
1362 	int error;
1363 	char *name;
1364 
1365 	name = devm_kasprintf(dev, GFP_KERNEL,
1366 			      "%s::wacom-%d.%d",
1367 			      dev_name(dev),
1368 			      group,
1369 			      id);
1370 	if (!name)
1371 		return -ENOMEM;
1372 
1373 	if (!read_only) {
1374 		led->trigger.name = name;
1375 		error = devm_led_trigger_register(dev, &led->trigger);
1376 		if (error) {
1377 			hid_err(wacom->hdev,
1378 				"failed to register LED trigger %s: %d\n",
1379 				led->cdev.name, error);
1380 			return error;
1381 		}
1382 	}
1383 
1384 	led->group = group;
1385 	led->id = id;
1386 	led->wacom = wacom;
1387 	led->llv = wacom->led.llv;
1388 	led->hlv = wacom->led.hlv;
1389 	led->cdev.name = name;
1390 	led->cdev.max_brightness = LED_FULL;
1391 	led->cdev.flags = LED_HW_PLUGGABLE;
1392 	led->cdev.brightness_get = __wacom_led_brightness_get;
1393 	if (!read_only) {
1394 		led->cdev.brightness_set_blocking = wacom_led_brightness_set;
1395 		led->cdev.default_trigger = led->cdev.name;
1396 	} else {
1397 		led->cdev.brightness_set = wacom_led_readonly_brightness_set;
1398 	}
1399 
1400 	error = devm_led_classdev_register(dev, &led->cdev);
1401 	if (error) {
1402 		hid_err(wacom->hdev,
1403 			"failed to register LED %s: %d\n",
1404 			led->cdev.name, error);
1405 		led->cdev.name = NULL;
1406 		return error;
1407 	}
1408 
1409 	return 0;
1410 }
1411 
1412 static void wacom_led_groups_release_one(void *data)
1413 {
1414 	struct wacom_group_leds *group = data;
1415 
1416 	devres_release_group(group->dev, group);
1417 }
1418 
1419 static int wacom_led_groups_alloc_and_register_one(struct device *dev,
1420 						   struct wacom *wacom,
1421 						   int group_id, int count,
1422 						   bool read_only)
1423 {
1424 	struct wacom_led *leds;
1425 	int i, error;
1426 
1427 	if (group_id >= wacom->led.count || count <= 0)
1428 		return -EINVAL;
1429 
1430 	if (!devres_open_group(dev, &wacom->led.groups[group_id], GFP_KERNEL))
1431 		return -ENOMEM;
1432 
1433 	leds = devm_kcalloc(dev, count, sizeof(struct wacom_led), GFP_KERNEL);
1434 	if (!leds) {
1435 		error = -ENOMEM;
1436 		goto err;
1437 	}
1438 
1439 	wacom->led.groups[group_id].leds = leds;
1440 	wacom->led.groups[group_id].count = count;
1441 
1442 	for (i = 0; i < count; i++) {
1443 		error = wacom_led_register_one(dev, wacom, &leds[i],
1444 					       group_id, i, read_only);
1445 		if (error)
1446 			goto err;
1447 	}
1448 
1449 	wacom->led.groups[group_id].dev = dev;
1450 
1451 	devres_close_group(dev, &wacom->led.groups[group_id]);
1452 
1453 	/*
1454 	 * There is a bug (?) in devm_led_classdev_register() in which its
1455 	 * increments the refcount of the parent. If the parent is an input
1456 	 * device, that means the ref count never reaches 0 when
1457 	 * devm_input_device_release() gets called.
1458 	 * This means that the LEDs are still there after disconnect.
1459 	 * Manually force the release of the group so that the leds are released
1460 	 * once we are done using them.
1461 	 */
1462 	error = devm_add_action_or_reset(&wacom->hdev->dev,
1463 					 wacom_led_groups_release_one,
1464 					 &wacom->led.groups[group_id]);
1465 	if (error)
1466 		return error;
1467 
1468 	return 0;
1469 
1470 err:
1471 	devres_release_group(dev, &wacom->led.groups[group_id]);
1472 	return error;
1473 }
1474 
1475 struct wacom_led *wacom_led_find(struct wacom *wacom, unsigned int group_id,
1476 				 unsigned int id)
1477 {
1478 	struct wacom_group_leds *group;
1479 
1480 	if (group_id >= wacom->led.count)
1481 		return NULL;
1482 
1483 	group = &wacom->led.groups[group_id];
1484 
1485 	if (!group->leds)
1486 		return NULL;
1487 
1488 	id %= group->count;
1489 
1490 	return &group->leds[id];
1491 }
1492 
1493 /*
1494  * wacom_led_next: gives the next available led with a wacom trigger.
1495  *
1496  * returns the next available struct wacom_led which has its default trigger
1497  * or the current one if none is available.
1498  */
1499 struct wacom_led *wacom_led_next(struct wacom *wacom, struct wacom_led *cur)
1500 {
1501 	struct wacom_led *next_led;
1502 	int group, next;
1503 
1504 	if (!wacom || !cur)
1505 		return NULL;
1506 
1507 	group = cur->group;
1508 	next = cur->id;
1509 
1510 	do {
1511 		next_led = wacom_led_find(wacom, group, ++next);
1512 		if (!next_led || next_led == cur)
1513 			return next_led;
1514 	} while (next_led->cdev.trigger != &next_led->trigger);
1515 
1516 	return next_led;
1517 }
1518 
1519 static void wacom_led_groups_release(void *data)
1520 {
1521 	struct wacom *wacom = data;
1522 
1523 	wacom->led.groups = NULL;
1524 	wacom->led.count = 0;
1525 }
1526 
1527 static int wacom_led_groups_allocate(struct wacom *wacom, int count)
1528 {
1529 	struct device *dev = &wacom->hdev->dev;
1530 	struct wacom_group_leds *groups;
1531 	int error;
1532 
1533 	groups = devm_kcalloc(dev, count, sizeof(struct wacom_group_leds),
1534 			      GFP_KERNEL);
1535 	if (!groups)
1536 		return -ENOMEM;
1537 
1538 	error = devm_add_action_or_reset(dev, wacom_led_groups_release, wacom);
1539 	if (error)
1540 		return error;
1541 
1542 	wacom->led.groups = groups;
1543 	wacom->led.count = count;
1544 
1545 	return 0;
1546 }
1547 
1548 static int wacom_leds_alloc_and_register(struct wacom *wacom, int group_count,
1549 					 int led_per_group, bool read_only)
1550 {
1551 	struct device *dev;
1552 	int i, error;
1553 
1554 	if (!wacom->wacom_wac.pad_input)
1555 		return -EINVAL;
1556 
1557 	dev = &wacom->wacom_wac.pad_input->dev;
1558 
1559 	error = wacom_led_groups_allocate(wacom, group_count);
1560 	if (error)
1561 		return error;
1562 
1563 	for (i = 0; i < group_count; i++) {
1564 		error = wacom_led_groups_alloc_and_register_one(dev, wacom, i,
1565 								led_per_group,
1566 								read_only);
1567 		if (error)
1568 			return error;
1569 	}
1570 
1571 	return 0;
1572 }
1573 
1574 int wacom_initialize_leds(struct wacom *wacom)
1575 {
1576 	int error;
1577 
1578 	if (!(wacom->wacom_wac.features.device_type & WACOM_DEVICETYPE_PAD))
1579 		return 0;
1580 
1581 	/* Initialize default values */
1582 	switch (wacom->wacom_wac.features.type) {
1583 	case HID_GENERIC:
1584 		if (!wacom->generic_has_leds)
1585 			return 0;
1586 		wacom->led.llv = 100;
1587 		wacom->led.max_llv = 100;
1588 
1589 		error = wacom_leds_alloc_and_register(wacom, 1, 4, false);
1590 		if (error) {
1591 			hid_err(wacom->hdev,
1592 				"cannot create leds err: %d\n", error);
1593 			return error;
1594 		}
1595 
1596 		error = wacom_devm_sysfs_create_group(wacom,
1597 						      &generic_led_attr_group);
1598 		break;
1599 
1600 	case INTUOS4S:
1601 	case INTUOS4:
1602 	case INTUOS4WL:
1603 	case INTUOS4L:
1604 		wacom->led.llv = 10;
1605 		wacom->led.hlv = 20;
1606 		wacom->led.max_llv = 127;
1607 		wacom->led.max_hlv = 127;
1608 		wacom->led.img_lum = 10;
1609 
1610 		error = wacom_leds_alloc_and_register(wacom, 1, 4, false);
1611 		if (error) {
1612 			hid_err(wacom->hdev,
1613 				"cannot create leds err: %d\n", error);
1614 			return error;
1615 		}
1616 
1617 		error = wacom_devm_sysfs_create_group(wacom,
1618 						      &intuos4_led_attr_group);
1619 		break;
1620 
1621 	case WACOM_24HD:
1622 	case WACOM_21UX2:
1623 		wacom->led.llv = 0;
1624 		wacom->led.hlv = 0;
1625 		wacom->led.img_lum = 0;
1626 
1627 		error = wacom_leds_alloc_and_register(wacom, 2, 4, false);
1628 		if (error) {
1629 			hid_err(wacom->hdev,
1630 				"cannot create leds err: %d\n", error);
1631 			return error;
1632 		}
1633 
1634 		error = wacom_devm_sysfs_create_group(wacom,
1635 						      &cintiq_led_attr_group);
1636 		break;
1637 
1638 	case INTUOS5S:
1639 	case INTUOS5:
1640 	case INTUOS5L:
1641 	case INTUOSPS:
1642 	case INTUOSPM:
1643 	case INTUOSPL:
1644 		wacom->led.llv = 32;
1645 		wacom->led.max_llv = 96;
1646 
1647 		error = wacom_leds_alloc_and_register(wacom, 1, 4, false);
1648 		if (error) {
1649 			hid_err(wacom->hdev,
1650 				"cannot create leds err: %d\n", error);
1651 			return error;
1652 		}
1653 
1654 		error = wacom_devm_sysfs_create_group(wacom,
1655 						      &intuos5_led_attr_group);
1656 		break;
1657 
1658 	case INTUOSP2_BT:
1659 		wacom->led.llv = 50;
1660 		wacom->led.max_llv = 100;
1661 		error = wacom_leds_alloc_and_register(wacom, 1, 4, false);
1662 		if (error) {
1663 			hid_err(wacom->hdev,
1664 				"cannot create leds err: %d\n", error);
1665 			return error;
1666 		}
1667 		return 0;
1668 
1669 	case REMOTE:
1670 		wacom->led.llv = 255;
1671 		wacom->led.max_llv = 255;
1672 		error = wacom_led_groups_allocate(wacom, 5);
1673 		if (error) {
1674 			hid_err(wacom->hdev,
1675 				"cannot create leds err: %d\n", error);
1676 			return error;
1677 		}
1678 		return 0;
1679 
1680 	default:
1681 		return 0;
1682 	}
1683 
1684 	if (error) {
1685 		hid_err(wacom->hdev,
1686 			"cannot create sysfs group err: %d\n", error);
1687 		return error;
1688 	}
1689 
1690 	return 0;
1691 }
1692 
1693 static void wacom_init_work(struct work_struct *work)
1694 {
1695 	struct wacom *wacom = container_of(work, struct wacom, init_work.work);
1696 
1697 	_wacom_query_tablet_data(wacom);
1698 	wacom_led_control(wacom);
1699 }
1700 
1701 static void wacom_query_tablet_data(struct wacom *wacom)
1702 {
1703 	schedule_delayed_work(&wacom->init_work, msecs_to_jiffies(1000));
1704 }
1705 
1706 static enum power_supply_property wacom_battery_props[] = {
1707 	POWER_SUPPLY_PROP_MODEL_NAME,
1708 	POWER_SUPPLY_PROP_PRESENT,
1709 	POWER_SUPPLY_PROP_STATUS,
1710 	POWER_SUPPLY_PROP_SCOPE,
1711 	POWER_SUPPLY_PROP_CAPACITY
1712 };
1713 
1714 static int wacom_battery_get_property(struct power_supply *psy,
1715 				      enum power_supply_property psp,
1716 				      union power_supply_propval *val)
1717 {
1718 	struct wacom_battery *battery = power_supply_get_drvdata(psy);
1719 	int ret = 0;
1720 
1721 	switch (psp) {
1722 		case POWER_SUPPLY_PROP_MODEL_NAME:
1723 			val->strval = battery->wacom->wacom_wac.name;
1724 			break;
1725 		case POWER_SUPPLY_PROP_PRESENT:
1726 			val->intval = battery->bat_connected;
1727 			break;
1728 		case POWER_SUPPLY_PROP_SCOPE:
1729 			val->intval = POWER_SUPPLY_SCOPE_DEVICE;
1730 			break;
1731 		case POWER_SUPPLY_PROP_CAPACITY:
1732 			val->intval = battery->battery_capacity;
1733 			break;
1734 		case POWER_SUPPLY_PROP_STATUS:
1735 			if (battery->bat_status != WACOM_POWER_SUPPLY_STATUS_AUTO)
1736 				val->intval = battery->bat_status;
1737 			else if (battery->bat_charging)
1738 				val->intval = POWER_SUPPLY_STATUS_CHARGING;
1739 			else if (battery->battery_capacity == 100 &&
1740 				    battery->ps_connected)
1741 				val->intval = POWER_SUPPLY_STATUS_FULL;
1742 			else if (battery->ps_connected)
1743 				val->intval = POWER_SUPPLY_STATUS_NOT_CHARGING;
1744 			else
1745 				val->intval = POWER_SUPPLY_STATUS_DISCHARGING;
1746 			break;
1747 		default:
1748 			ret = -EINVAL;
1749 			break;
1750 	}
1751 
1752 	return ret;
1753 }
1754 
1755 static int __wacom_initialize_battery(struct wacom *wacom,
1756 				      struct wacom_battery *battery)
1757 {
1758 	static atomic_t battery_no = ATOMIC_INIT(0);
1759 	struct device *dev = &wacom->hdev->dev;
1760 	struct power_supply_config psy_cfg = { .drv_data = battery, };
1761 	struct power_supply *ps_bat;
1762 	struct power_supply_desc *bat_desc = &battery->bat_desc;
1763 	unsigned long n;
1764 	int error;
1765 
1766 	if (!devres_open_group(dev, bat_desc, GFP_KERNEL))
1767 		return -ENOMEM;
1768 
1769 	battery->wacom = wacom;
1770 
1771 	n = atomic_inc_return(&battery_no) - 1;
1772 
1773 	bat_desc->properties = wacom_battery_props;
1774 	bat_desc->num_properties = ARRAY_SIZE(wacom_battery_props);
1775 	bat_desc->get_property = wacom_battery_get_property;
1776 	sprintf(battery->bat_name, "wacom_battery_%ld", n);
1777 	bat_desc->name = battery->bat_name;
1778 	bat_desc->type = POWER_SUPPLY_TYPE_BATTERY;
1779 	bat_desc->use_for_apm = 0;
1780 
1781 	ps_bat = devm_power_supply_register(dev, bat_desc, &psy_cfg);
1782 	if (IS_ERR(ps_bat)) {
1783 		error = PTR_ERR(ps_bat);
1784 		goto err;
1785 	}
1786 
1787 	power_supply_powers(ps_bat, &wacom->hdev->dev);
1788 
1789 	battery->battery = ps_bat;
1790 
1791 	devres_close_group(dev, bat_desc);
1792 	return 0;
1793 
1794 err:
1795 	devres_release_group(dev, bat_desc);
1796 	return error;
1797 }
1798 
1799 static int wacom_initialize_battery(struct wacom *wacom)
1800 {
1801 	if (wacom->wacom_wac.features.quirks & WACOM_QUIRK_BATTERY)
1802 		return __wacom_initialize_battery(wacom, &wacom->battery);
1803 
1804 	return 0;
1805 }
1806 
1807 static void wacom_destroy_battery(struct wacom *wacom)
1808 {
1809 	if (wacom->battery.battery) {
1810 		devres_release_group(&wacom->hdev->dev,
1811 				     &wacom->battery.bat_desc);
1812 		wacom->battery.battery = NULL;
1813 	}
1814 }
1815 
1816 static ssize_t wacom_show_speed(struct device *dev,
1817 				struct device_attribute
1818 				*attr, char *buf)
1819 {
1820 	struct hid_device *hdev = to_hid_device(dev);
1821 	struct wacom *wacom = hid_get_drvdata(hdev);
1822 
1823 	return sysfs_emit(buf, "%i\n", wacom->wacom_wac.bt_high_speed);
1824 }
1825 
1826 static ssize_t wacom_store_speed(struct device *dev,
1827 				struct device_attribute *attr,
1828 				const char *buf, size_t count)
1829 {
1830 	struct hid_device *hdev = to_hid_device(dev);
1831 	struct wacom *wacom = hid_get_drvdata(hdev);
1832 	u8 new_speed;
1833 
1834 	if (kstrtou8(buf, 0, &new_speed))
1835 		return -EINVAL;
1836 
1837 	if (new_speed != 0 && new_speed != 1)
1838 		return -EINVAL;
1839 
1840 	wacom_bt_query_tablet_data(hdev, new_speed, &wacom->wacom_wac.features);
1841 
1842 	return count;
1843 }
1844 
1845 static DEVICE_ATTR(speed, DEV_ATTR_RW_PERM,
1846 		wacom_show_speed, wacom_store_speed);
1847 
1848 
1849 static ssize_t wacom_show_remote_mode(struct kobject *kobj,
1850 				      struct kobj_attribute *kattr,
1851 				      char *buf, int index)
1852 {
1853 	struct device *dev = kobj_to_dev(kobj->parent);
1854 	struct hid_device *hdev = to_hid_device(dev);
1855 	struct wacom *wacom = hid_get_drvdata(hdev);
1856 	u8 mode;
1857 
1858 	mode = wacom->led.groups[index].select;
1859 	return sprintf(buf, "%d\n", mode < 3 ? mode : -1);
1860 }
1861 
1862 #define DEVICE_EKR_ATTR_GROUP(SET_ID)					\
1863 static ssize_t wacom_show_remote##SET_ID##_mode(struct kobject *kobj,	\
1864 			       struct kobj_attribute *kattr, char *buf)	\
1865 {									\
1866 	return wacom_show_remote_mode(kobj, kattr, buf, SET_ID);	\
1867 }									\
1868 static struct kobj_attribute remote##SET_ID##_mode_attr = {		\
1869 	.attr = {.name = "remote_mode",					\
1870 		.mode = DEV_ATTR_RO_PERM},				\
1871 	.show = wacom_show_remote##SET_ID##_mode,			\
1872 };									\
1873 static struct attribute *remote##SET_ID##_serial_attrs[] = {		\
1874 	&remote##SET_ID##_mode_attr.attr,				\
1875 	NULL								\
1876 };									\
1877 static const struct attribute_group remote##SET_ID##_serial_group = {	\
1878 	.name = NULL,							\
1879 	.attrs = remote##SET_ID##_serial_attrs,				\
1880 }
1881 
1882 DEVICE_EKR_ATTR_GROUP(0);
1883 DEVICE_EKR_ATTR_GROUP(1);
1884 DEVICE_EKR_ATTR_GROUP(2);
1885 DEVICE_EKR_ATTR_GROUP(3);
1886 DEVICE_EKR_ATTR_GROUP(4);
1887 
1888 static int wacom_remote_create_attr_group(struct wacom *wacom, __u32 serial,
1889 					  int index)
1890 {
1891 	int error = 0;
1892 	struct wacom_remote *remote = wacom->remote;
1893 
1894 	remote->remotes[index].group.name = devm_kasprintf(&wacom->hdev->dev,
1895 							  GFP_KERNEL,
1896 							  "%d", serial);
1897 	if (!remote->remotes[index].group.name)
1898 		return -ENOMEM;
1899 
1900 	error = __wacom_devm_sysfs_create_group(wacom, remote->remote_dir,
1901 						&remote->remotes[index].group);
1902 	if (error) {
1903 		remote->remotes[index].group.name = NULL;
1904 		hid_err(wacom->hdev,
1905 			"cannot create sysfs group err: %d\n", error);
1906 		return error;
1907 	}
1908 
1909 	return 0;
1910 }
1911 
1912 static int wacom_cmd_unpair_remote(struct wacom *wacom, unsigned char selector)
1913 {
1914 	const size_t buf_size = 2;
1915 	unsigned char *buf;
1916 	int retval;
1917 
1918 	buf = kzalloc(buf_size, GFP_KERNEL);
1919 	if (!buf)
1920 		return -ENOMEM;
1921 
1922 	buf[0] = WAC_CMD_DELETE_PAIRING;
1923 	buf[1] = selector;
1924 
1925 	retval = wacom_set_report(wacom->hdev, HID_OUTPUT_REPORT, buf,
1926 				  buf_size, WAC_CMD_RETRIES);
1927 	kfree(buf);
1928 
1929 	return retval;
1930 }
1931 
1932 static ssize_t wacom_store_unpair_remote(struct kobject *kobj,
1933 					 struct kobj_attribute *attr,
1934 					 const char *buf, size_t count)
1935 {
1936 	unsigned char selector = 0;
1937 	struct device *dev = kobj_to_dev(kobj->parent);
1938 	struct hid_device *hdev = to_hid_device(dev);
1939 	struct wacom *wacom = hid_get_drvdata(hdev);
1940 	int err;
1941 
1942 	if (!strncmp(buf, "*\n", 2)) {
1943 		selector = WAC_CMD_UNPAIR_ALL;
1944 	} else {
1945 		hid_info(wacom->hdev, "remote: unrecognized unpair code: %s\n",
1946 			 buf);
1947 		return -1;
1948 	}
1949 
1950 	mutex_lock(&wacom->lock);
1951 
1952 	err = wacom_cmd_unpair_remote(wacom, selector);
1953 	mutex_unlock(&wacom->lock);
1954 
1955 	return err < 0 ? err : count;
1956 }
1957 
1958 static struct kobj_attribute unpair_remote_attr = {
1959 	.attr = {.name = "unpair_remote", .mode = 0200},
1960 	.store = wacom_store_unpair_remote,
1961 };
1962 
1963 static const struct attribute *remote_unpair_attrs[] = {
1964 	&unpair_remote_attr.attr,
1965 	NULL
1966 };
1967 
1968 static void wacom_remotes_destroy(void *data)
1969 {
1970 	struct wacom *wacom = data;
1971 	struct wacom_remote *remote = wacom->remote;
1972 
1973 	if (!remote)
1974 		return;
1975 
1976 	kobject_put(remote->remote_dir);
1977 	kfifo_free(&remote->remote_fifo);
1978 	wacom->remote = NULL;
1979 }
1980 
1981 static int wacom_initialize_remotes(struct wacom *wacom)
1982 {
1983 	int error = 0;
1984 	struct wacom_remote *remote;
1985 	int i;
1986 
1987 	if (wacom->wacom_wac.features.type != REMOTE)
1988 		return 0;
1989 
1990 	remote = devm_kzalloc(&wacom->hdev->dev, sizeof(*wacom->remote),
1991 			      GFP_KERNEL);
1992 	if (!remote)
1993 		return -ENOMEM;
1994 
1995 	wacom->remote = remote;
1996 
1997 	spin_lock_init(&remote->remote_lock);
1998 
1999 	error = kfifo_alloc(&remote->remote_fifo,
2000 			5 * sizeof(struct wacom_remote_work_data),
2001 			GFP_KERNEL);
2002 	if (error) {
2003 		hid_err(wacom->hdev, "failed allocating remote_fifo\n");
2004 		return -ENOMEM;
2005 	}
2006 
2007 	remote->remotes[0].group = remote0_serial_group;
2008 	remote->remotes[1].group = remote1_serial_group;
2009 	remote->remotes[2].group = remote2_serial_group;
2010 	remote->remotes[3].group = remote3_serial_group;
2011 	remote->remotes[4].group = remote4_serial_group;
2012 
2013 	remote->remote_dir = kobject_create_and_add("wacom_remote",
2014 						    &wacom->hdev->dev.kobj);
2015 	if (!remote->remote_dir)
2016 		return -ENOMEM;
2017 
2018 	error = sysfs_create_files(remote->remote_dir, remote_unpair_attrs);
2019 
2020 	if (error) {
2021 		hid_err(wacom->hdev,
2022 			"cannot create sysfs group err: %d\n", error);
2023 		return error;
2024 	}
2025 
2026 	for (i = 0; i < WACOM_MAX_REMOTES; i++) {
2027 		wacom->led.groups[i].select = WACOM_STATUS_UNKNOWN;
2028 		remote->remotes[i].serial = 0;
2029 	}
2030 
2031 	error = devm_add_action_or_reset(&wacom->hdev->dev,
2032 					 wacom_remotes_destroy, wacom);
2033 	if (error)
2034 		return error;
2035 
2036 	return 0;
2037 }
2038 
2039 static struct input_dev *wacom_allocate_input(struct wacom *wacom)
2040 {
2041 	struct input_dev *input_dev;
2042 	struct hid_device *hdev = wacom->hdev;
2043 	struct wacom_wac *wacom_wac = &(wacom->wacom_wac);
2044 
2045 	input_dev = devm_input_allocate_device(&hdev->dev);
2046 	if (!input_dev)
2047 		return NULL;
2048 
2049 	input_dev->name = wacom_wac->features.name;
2050 	input_dev->phys = hdev->phys;
2051 	input_dev->dev.parent = &hdev->dev;
2052 	input_dev->open = wacom_open;
2053 	input_dev->close = wacom_close;
2054 	input_dev->uniq = hdev->uniq;
2055 	input_dev->id.bustype = hdev->bus;
2056 	input_dev->id.vendor  = hdev->vendor;
2057 	input_dev->id.product = wacom_wac->pid ? wacom_wac->pid : hdev->product;
2058 	input_dev->id.version = hdev->version;
2059 	input_set_drvdata(input_dev, wacom);
2060 
2061 	return input_dev;
2062 }
2063 
2064 static int wacom_allocate_inputs(struct wacom *wacom)
2065 {
2066 	struct wacom_wac *wacom_wac = &(wacom->wacom_wac);
2067 
2068 	wacom_wac->pen_input = wacom_allocate_input(wacom);
2069 	wacom_wac->touch_input = wacom_allocate_input(wacom);
2070 	wacom_wac->pad_input = wacom_allocate_input(wacom);
2071 	if (!wacom_wac->pen_input ||
2072 	    !wacom_wac->touch_input ||
2073 	    !wacom_wac->pad_input)
2074 		return -ENOMEM;
2075 
2076 	wacom_wac->pen_input->name = wacom_wac->pen_name;
2077 	wacom_wac->touch_input->name = wacom_wac->touch_name;
2078 	wacom_wac->pad_input->name = wacom_wac->pad_name;
2079 
2080 	return 0;
2081 }
2082 
2083 static int wacom_register_inputs(struct wacom *wacom)
2084 {
2085 	struct input_dev *pen_input_dev, *touch_input_dev, *pad_input_dev;
2086 	struct wacom_wac *wacom_wac = &(wacom->wacom_wac);
2087 	int error = 0;
2088 
2089 	pen_input_dev = wacom_wac->pen_input;
2090 	touch_input_dev = wacom_wac->touch_input;
2091 	pad_input_dev = wacom_wac->pad_input;
2092 
2093 	if (!pen_input_dev || !touch_input_dev || !pad_input_dev)
2094 		return -EINVAL;
2095 
2096 	error = wacom_setup_pen_input_capabilities(pen_input_dev, wacom_wac);
2097 	if (error) {
2098 		/* no pen in use on this interface */
2099 		input_free_device(pen_input_dev);
2100 		wacom_wac->pen_input = NULL;
2101 		pen_input_dev = NULL;
2102 	} else {
2103 		error = input_register_device(pen_input_dev);
2104 		if (error)
2105 			goto fail;
2106 	}
2107 
2108 	error = wacom_setup_touch_input_capabilities(touch_input_dev, wacom_wac);
2109 	if (error) {
2110 		/* no touch in use on this interface */
2111 		input_free_device(touch_input_dev);
2112 		wacom_wac->touch_input = NULL;
2113 		touch_input_dev = NULL;
2114 	} else {
2115 		error = input_register_device(touch_input_dev);
2116 		if (error)
2117 			goto fail;
2118 	}
2119 
2120 	error = wacom_setup_pad_input_capabilities(pad_input_dev, wacom_wac);
2121 	if (error) {
2122 		/* no pad events using this interface */
2123 		input_free_device(pad_input_dev);
2124 		wacom_wac->pad_input = NULL;
2125 		pad_input_dev = NULL;
2126 	} else {
2127 		error = input_register_device(pad_input_dev);
2128 		if (error)
2129 			goto fail;
2130 	}
2131 
2132 	return 0;
2133 
2134 fail:
2135 	wacom_wac->pad_input = NULL;
2136 	wacom_wac->touch_input = NULL;
2137 	wacom_wac->pen_input = NULL;
2138 	return error;
2139 }
2140 
2141 /*
2142  * Not all devices report physical dimensions from HID.
2143  * Compute the default from hardcoded logical dimension
2144  * and resolution before driver overwrites them.
2145  */
2146 static void wacom_set_default_phy(struct wacom_features *features)
2147 {
2148 	if (features->x_resolution) {
2149 		features->x_phy = (features->x_max * 100) /
2150 					features->x_resolution;
2151 		features->y_phy = (features->y_max * 100) /
2152 					features->y_resolution;
2153 	}
2154 }
2155 
2156 static void wacom_calculate_res(struct wacom_features *features)
2157 {
2158 	/* set unit to "100th of a mm" for devices not reported by HID */
2159 	if (!features->unit) {
2160 		features->unit = 0x11;
2161 		features->unitExpo = -3;
2162 	}
2163 
2164 	features->x_resolution = wacom_calc_hid_res(features->x_max,
2165 						    features->x_phy,
2166 						    features->unit,
2167 						    features->unitExpo);
2168 	features->y_resolution = wacom_calc_hid_res(features->y_max,
2169 						    features->y_phy,
2170 						    features->unit,
2171 						    features->unitExpo);
2172 }
2173 
2174 void wacom_battery_work(struct work_struct *work)
2175 {
2176 	struct wacom *wacom = container_of(work, struct wacom, battery_work);
2177 
2178 	if ((wacom->wacom_wac.features.quirks & WACOM_QUIRK_BATTERY) &&
2179 	     !wacom->battery.battery) {
2180 		wacom_initialize_battery(wacom);
2181 	}
2182 	else if (!(wacom->wacom_wac.features.quirks & WACOM_QUIRK_BATTERY) &&
2183 		 wacom->battery.battery) {
2184 		wacom_destroy_battery(wacom);
2185 	}
2186 }
2187 
2188 static size_t wacom_compute_pktlen(struct hid_device *hdev)
2189 {
2190 	struct hid_report_enum *report_enum;
2191 	struct hid_report *report;
2192 	size_t size = 0;
2193 
2194 	report_enum = hdev->report_enum + HID_INPUT_REPORT;
2195 
2196 	list_for_each_entry(report, &report_enum->report_list, list) {
2197 		size_t report_size = hid_report_len(report);
2198 		if (report_size > size)
2199 			size = report_size;
2200 	}
2201 
2202 	return size;
2203 }
2204 
2205 static void wacom_update_name(struct wacom *wacom, const char *suffix)
2206 {
2207 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
2208 	struct wacom_features *features = &wacom_wac->features;
2209 	char name[WACOM_NAME_MAX - 20]; /* Leave some room for suffixes */
2210 
2211 	/* Generic devices name unspecified */
2212 	if ((features->type == HID_GENERIC) && !strcmp("Wacom HID", features->name)) {
2213 		char *product_name = wacom->hdev->name;
2214 
2215 		if (hid_is_usb(wacom->hdev)) {
2216 			struct usb_interface *intf = to_usb_interface(wacom->hdev->dev.parent);
2217 			struct usb_device *dev = interface_to_usbdev(intf);
2218 			product_name = dev->product;
2219 		}
2220 
2221 		if (wacom->hdev->bus == BUS_I2C) {
2222 			snprintf(name, sizeof(name), "%s %X",
2223 				 features->name, wacom->hdev->product);
2224 		} else if (strstr(product_name, "Wacom") ||
2225 			   strstr(product_name, "wacom") ||
2226 			   strstr(product_name, "WACOM")) {
2227 			if (strscpy(name, product_name, sizeof(name)) < 0) {
2228 				hid_warn(wacom->hdev, "String overflow while assembling device name");
2229 			}
2230 		} else {
2231 			snprintf(name, sizeof(name), "Wacom %s", product_name);
2232 		}
2233 
2234 		/* strip out excess whitespaces */
2235 		while (1) {
2236 			char *gap = strstr(name, "  ");
2237 			if (gap == NULL)
2238 				break;
2239 			/* shift everything including the terminator */
2240 			memmove(gap, gap+1, strlen(gap));
2241 		}
2242 
2243 		/* get rid of trailing whitespace */
2244 		if (name[strlen(name)-1] == ' ')
2245 			name[strlen(name)-1] = '\0';
2246 	} else {
2247 		if (strscpy(name, features->name, sizeof(name)) < 0) {
2248 			hid_warn(wacom->hdev, "String overflow while assembling device name");
2249 		}
2250 	}
2251 
2252 	snprintf(wacom_wac->name, sizeof(wacom_wac->name), "%s%s",
2253 		 name, suffix);
2254 
2255 	/* Append the device type to the name */
2256 	snprintf(wacom_wac->pen_name, sizeof(wacom_wac->pen_name),
2257 		"%s%s Pen", name, suffix);
2258 	snprintf(wacom_wac->touch_name, sizeof(wacom_wac->touch_name),
2259 		"%s%s Finger", name, suffix);
2260 	snprintf(wacom_wac->pad_name, sizeof(wacom_wac->pad_name),
2261 		"%s%s Pad", name, suffix);
2262 }
2263 
2264 static void wacom_release_resources(struct wacom *wacom)
2265 {
2266 	struct hid_device *hdev = wacom->hdev;
2267 
2268 	if (!wacom->resources)
2269 		return;
2270 
2271 	devres_release_group(&hdev->dev, wacom);
2272 
2273 	wacom->resources = false;
2274 
2275 	wacom->wacom_wac.pen_input = NULL;
2276 	wacom->wacom_wac.touch_input = NULL;
2277 	wacom->wacom_wac.pad_input = NULL;
2278 }
2279 
2280 static void wacom_set_shared_values(struct wacom_wac *wacom_wac)
2281 {
2282 	if (wacom_wac->features.device_type & WACOM_DEVICETYPE_TOUCH) {
2283 		wacom_wac->shared->type = wacom_wac->features.type;
2284 		wacom_wac->shared->touch_input = wacom_wac->touch_input;
2285 	}
2286 
2287 	if (wacom_wac->has_mute_touch_switch) {
2288 		wacom_wac->shared->has_mute_touch_switch = true;
2289 		/* Hardware touch switch may be off. Wait until
2290 		 * we know the switch state to decide is_touch_on.
2291 		 * Softkey state should be initialized to "on" to
2292 		 * match historic default.
2293 		 */
2294 		if (wacom_wac->is_soft_touch_switch)
2295 			wacom_wac->shared->is_touch_on = true;
2296 	}
2297 
2298 	if (wacom_wac->shared->has_mute_touch_switch &&
2299 	    wacom_wac->shared->touch_input) {
2300 		set_bit(EV_SW, wacom_wac->shared->touch_input->evbit);
2301 		input_set_capability(wacom_wac->shared->touch_input, EV_SW,
2302 				     SW_MUTE_DEVICE);
2303 	}
2304 }
2305 
2306 static int wacom_parse_and_register(struct wacom *wacom, bool wireless)
2307 {
2308 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
2309 	struct wacom_features *features = &wacom_wac->features;
2310 	struct hid_device *hdev = wacom->hdev;
2311 	int error;
2312 	unsigned int connect_mask = HID_CONNECT_HIDRAW;
2313 
2314 	features->pktlen = wacom_compute_pktlen(hdev);
2315 	if (features->pktlen > WACOM_PKGLEN_MAX)
2316 		return -EINVAL;
2317 
2318 	if (!devres_open_group(&hdev->dev, wacom, GFP_KERNEL))
2319 		return -ENOMEM;
2320 
2321 	wacom->resources = true;
2322 
2323 	error = wacom_allocate_inputs(wacom);
2324 	if (error)
2325 		goto fail;
2326 
2327 	/*
2328 	 * Bamboo Pad has a generic hid handling for the Pen, and we switch it
2329 	 * into debug mode for the touch part.
2330 	 * We ignore the other interfaces.
2331 	 */
2332 	if (features->type == BAMBOO_PAD) {
2333 		if (features->pktlen == WACOM_PKGLEN_PENABLED) {
2334 			features->type = HID_GENERIC;
2335 		} else if ((features->pktlen != WACOM_PKGLEN_BPAD_TOUCH) &&
2336 			   (features->pktlen != WACOM_PKGLEN_BPAD_TOUCH_USB)) {
2337 			error = -ENODEV;
2338 			goto fail;
2339 		}
2340 	}
2341 
2342 	/* set the default size in case we do not get them from hid */
2343 	wacom_set_default_phy(features);
2344 
2345 	/* Retrieve the physical and logical size for touch devices */
2346 	wacom_retrieve_hid_descriptor(hdev, features);
2347 	wacom_setup_device_quirks(wacom);
2348 
2349 	if (features->device_type == WACOM_DEVICETYPE_NONE &&
2350 	    features->type != WIRELESS) {
2351 		error = features->type == HID_GENERIC ? -ENODEV : 0;
2352 
2353 		dev_warn(&hdev->dev, "Unknown device_type for '%s'. %s.",
2354 			 hdev->name,
2355 			 error ? "Ignoring" : "Assuming pen");
2356 
2357 		if (error)
2358 			goto fail;
2359 
2360 		features->device_type |= WACOM_DEVICETYPE_PEN;
2361 	}
2362 
2363 	wacom_calculate_res(features);
2364 
2365 	wacom_update_name(wacom, wireless ? " (WL)" : "");
2366 
2367 	/* pen only Bamboo neither support touch nor pad */
2368 	if ((features->type == BAMBOO_PEN) &&
2369 	    ((features->device_type & WACOM_DEVICETYPE_TOUCH) ||
2370 	    (features->device_type & WACOM_DEVICETYPE_PAD))) {
2371 		error = -ENODEV;
2372 		goto fail;
2373 	}
2374 
2375 	error = wacom_add_shared_data(hdev);
2376 	if (error)
2377 		goto fail;
2378 
2379 	error = wacom_register_inputs(wacom);
2380 	if (error)
2381 		goto fail;
2382 
2383 	if (wacom->wacom_wac.features.device_type & WACOM_DEVICETYPE_PAD) {
2384 		error = wacom_initialize_leds(wacom);
2385 		if (error)
2386 			goto fail;
2387 
2388 		error = wacom_initialize_remotes(wacom);
2389 		if (error)
2390 			goto fail;
2391 	}
2392 
2393 	if (features->type == HID_GENERIC)
2394 		connect_mask |= HID_CONNECT_DRIVER;
2395 
2396 	/* Regular HID work starts now */
2397 	error = hid_hw_start(hdev, connect_mask);
2398 	if (error) {
2399 		hid_err(hdev, "hw start failed\n");
2400 		goto fail;
2401 	}
2402 
2403 	if (!wireless) {
2404 		/* Note that if query fails it is not a hard failure */
2405 		wacom_query_tablet_data(wacom);
2406 	}
2407 
2408 	/* touch only Bamboo doesn't support pen */
2409 	if ((features->type == BAMBOO_TOUCH) &&
2410 	    (features->device_type & WACOM_DEVICETYPE_PEN)) {
2411 		cancel_delayed_work_sync(&wacom->init_work);
2412 		_wacom_query_tablet_data(wacom);
2413 		error = -ENODEV;
2414 		goto fail_quirks;
2415 	}
2416 
2417 	if (features->device_type & WACOM_DEVICETYPE_WL_MONITOR) {
2418 		error = hid_hw_open(hdev);
2419 		if (error) {
2420 			hid_err(hdev, "hw open failed\n");
2421 			goto fail_quirks;
2422 		}
2423 	}
2424 
2425 	wacom_set_shared_values(wacom_wac);
2426 	devres_close_group(&hdev->dev, wacom);
2427 
2428 	return 0;
2429 
2430 fail_quirks:
2431 	hid_hw_stop(hdev);
2432 fail:
2433 	wacom_release_resources(wacom);
2434 	return error;
2435 }
2436 
2437 static void wacom_wireless_work(struct work_struct *work)
2438 {
2439 	struct wacom *wacom = container_of(work, struct wacom, wireless_work);
2440 	struct usb_device *usbdev = wacom->usbdev;
2441 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
2442 	struct hid_device *hdev1, *hdev2;
2443 	struct wacom *wacom1, *wacom2;
2444 	struct wacom_wac *wacom_wac1, *wacom_wac2;
2445 	int error;
2446 
2447 	/*
2448 	 * Regardless if this is a disconnect or a new tablet,
2449 	 * remove any existing input and battery devices.
2450 	 */
2451 
2452 	wacom_destroy_battery(wacom);
2453 
2454 	if (!usbdev)
2455 		return;
2456 
2457 	/* Stylus interface */
2458 	hdev1 = usb_get_intfdata(usbdev->config->interface[1]);
2459 	wacom1 = hid_get_drvdata(hdev1);
2460 	wacom_wac1 = &(wacom1->wacom_wac);
2461 	wacom_release_resources(wacom1);
2462 
2463 	/* Touch interface */
2464 	hdev2 = usb_get_intfdata(usbdev->config->interface[2]);
2465 	wacom2 = hid_get_drvdata(hdev2);
2466 	wacom_wac2 = &(wacom2->wacom_wac);
2467 	wacom_release_resources(wacom2);
2468 
2469 	if (wacom_wac->pid == 0) {
2470 		hid_info(wacom->hdev, "wireless tablet disconnected\n");
2471 	} else {
2472 		const struct hid_device_id *id = wacom_ids;
2473 
2474 		hid_info(wacom->hdev, "wireless tablet connected with PID %x\n",
2475 			 wacom_wac->pid);
2476 
2477 		while (id->bus) {
2478 			if (id->vendor == USB_VENDOR_ID_WACOM &&
2479 			    id->product == wacom_wac->pid)
2480 				break;
2481 			id++;
2482 		}
2483 
2484 		if (!id->bus) {
2485 			hid_info(wacom->hdev, "ignoring unknown PID.\n");
2486 			return;
2487 		}
2488 
2489 		/* Stylus interface */
2490 		wacom_wac1->features =
2491 			*((struct wacom_features *)id->driver_data);
2492 
2493 		wacom_wac1->pid = wacom_wac->pid;
2494 		hid_hw_stop(hdev1);
2495 		error = wacom_parse_and_register(wacom1, true);
2496 		if (error)
2497 			goto fail;
2498 
2499 		/* Touch interface */
2500 		if (wacom_wac1->features.touch_max ||
2501 		    (wacom_wac1->features.type >= INTUOSHT &&
2502 		    wacom_wac1->features.type <= BAMBOO_PT)) {
2503 			wacom_wac2->features =
2504 				*((struct wacom_features *)id->driver_data);
2505 			wacom_wac2->pid = wacom_wac->pid;
2506 			hid_hw_stop(hdev2);
2507 			error = wacom_parse_and_register(wacom2, true);
2508 			if (error)
2509 				goto fail;
2510 		}
2511 
2512 		if (strscpy(wacom_wac->name, wacom_wac1->name,
2513 			sizeof(wacom_wac->name)) < 0) {
2514 			hid_warn(wacom->hdev, "String overflow while assembling device name");
2515 		}
2516 	}
2517 
2518 	return;
2519 
2520 fail:
2521 	wacom_release_resources(wacom1);
2522 	wacom_release_resources(wacom2);
2523 	return;
2524 }
2525 
2526 static void wacom_remote_destroy_battery(struct wacom *wacom, int index)
2527 {
2528 	struct wacom_remote *remote = wacom->remote;
2529 
2530 	if (remote->remotes[index].battery.battery) {
2531 		devres_release_group(&wacom->hdev->dev,
2532 				     &remote->remotes[index].battery.bat_desc);
2533 		remote->remotes[index].battery.battery = NULL;
2534 		remote->remotes[index].active_time = 0;
2535 	}
2536 }
2537 
2538 static void wacom_remote_destroy_one(struct wacom *wacom, unsigned int index)
2539 {
2540 	struct wacom_remote *remote = wacom->remote;
2541 	u32 serial = remote->remotes[index].serial;
2542 	int i;
2543 	unsigned long flags;
2544 
2545 	for (i = 0; i < WACOM_MAX_REMOTES; i++) {
2546 		if (remote->remotes[i].serial == serial) {
2547 
2548 			spin_lock_irqsave(&remote->remote_lock, flags);
2549 			remote->remotes[i].registered = false;
2550 			spin_unlock_irqrestore(&remote->remote_lock, flags);
2551 
2552 			wacom_remote_destroy_battery(wacom, i);
2553 
2554 			if (remote->remotes[i].group.name)
2555 				devres_release_group(&wacom->hdev->dev,
2556 						     &remote->remotes[i]);
2557 
2558 			remote->remotes[i].serial = 0;
2559 			remote->remotes[i].group.name = NULL;
2560 			wacom->led.groups[i].select = WACOM_STATUS_UNKNOWN;
2561 		}
2562 	}
2563 }
2564 
2565 static int wacom_remote_create_one(struct wacom *wacom, u32 serial,
2566 				   unsigned int index)
2567 {
2568 	struct wacom_remote *remote = wacom->remote;
2569 	struct device *dev = &wacom->hdev->dev;
2570 	int error, k;
2571 
2572 	/* A remote can pair more than once with an EKR,
2573 	 * check to make sure this serial isn't already paired.
2574 	 */
2575 	for (k = 0; k < WACOM_MAX_REMOTES; k++) {
2576 		if (remote->remotes[k].serial == serial)
2577 			break;
2578 	}
2579 
2580 	if (k < WACOM_MAX_REMOTES) {
2581 		remote->remotes[index].serial = serial;
2582 		return 0;
2583 	}
2584 
2585 	if (!devres_open_group(dev, &remote->remotes[index], GFP_KERNEL))
2586 		return -ENOMEM;
2587 
2588 	error = wacom_remote_create_attr_group(wacom, serial, index);
2589 	if (error)
2590 		goto fail;
2591 
2592 	remote->remotes[index].input = wacom_allocate_input(wacom);
2593 	if (!remote->remotes[index].input) {
2594 		error = -ENOMEM;
2595 		goto fail;
2596 	}
2597 	remote->remotes[index].input->uniq = remote->remotes[index].group.name;
2598 	remote->remotes[index].input->name = wacom->wacom_wac.pad_name;
2599 
2600 	if (!remote->remotes[index].input->name) {
2601 		error = -EINVAL;
2602 		goto fail;
2603 	}
2604 
2605 	error = wacom_setup_pad_input_capabilities(remote->remotes[index].input,
2606 						   &wacom->wacom_wac);
2607 	if (error)
2608 		goto fail;
2609 
2610 	remote->remotes[index].serial = serial;
2611 
2612 	error = input_register_device(remote->remotes[index].input);
2613 	if (error)
2614 		goto fail;
2615 
2616 	error = wacom_led_groups_alloc_and_register_one(
2617 					&remote->remotes[index].input->dev,
2618 					wacom, index, 3, true);
2619 	if (error)
2620 		goto fail;
2621 
2622 	remote->remotes[index].registered = true;
2623 
2624 	devres_close_group(dev, &remote->remotes[index]);
2625 	return 0;
2626 
2627 fail:
2628 	devres_release_group(dev, &remote->remotes[index]);
2629 	remote->remotes[index].serial = 0;
2630 	return error;
2631 }
2632 
2633 static int wacom_remote_attach_battery(struct wacom *wacom, int index)
2634 {
2635 	struct wacom_remote *remote = wacom->remote;
2636 	int error;
2637 
2638 	if (!remote->remotes[index].registered)
2639 		return 0;
2640 
2641 	if (remote->remotes[index].battery.battery)
2642 		return 0;
2643 
2644 	if (!remote->remotes[index].active_time)
2645 		return 0;
2646 
2647 	if (wacom->led.groups[index].select == WACOM_STATUS_UNKNOWN)
2648 		return 0;
2649 
2650 	error = __wacom_initialize_battery(wacom,
2651 					&wacom->remote->remotes[index].battery);
2652 	if (error)
2653 		return error;
2654 
2655 	return 0;
2656 }
2657 
2658 static void wacom_remote_work(struct work_struct *work)
2659 {
2660 	struct wacom *wacom = container_of(work, struct wacom, remote_work);
2661 	struct wacom_remote *remote = wacom->remote;
2662 	ktime_t kt = ktime_get();
2663 	struct wacom_remote_work_data remote_work_data;
2664 	unsigned long flags;
2665 	unsigned int count;
2666 	u32 work_serial;
2667 	int i;
2668 
2669 	spin_lock_irqsave(&remote->remote_lock, flags);
2670 
2671 	count = kfifo_out(&remote->remote_fifo, &remote_work_data,
2672 			  sizeof(remote_work_data));
2673 
2674 	if (count != sizeof(remote_work_data)) {
2675 		hid_err(wacom->hdev,
2676 			"workitem triggered without status available\n");
2677 		spin_unlock_irqrestore(&remote->remote_lock, flags);
2678 		return;
2679 	}
2680 
2681 	if (!kfifo_is_empty(&remote->remote_fifo))
2682 		wacom_schedule_work(&wacom->wacom_wac, WACOM_WORKER_REMOTE);
2683 
2684 	spin_unlock_irqrestore(&remote->remote_lock, flags);
2685 
2686 	for (i = 0; i < WACOM_MAX_REMOTES; i++) {
2687 		work_serial = remote_work_data.remote[i].serial;
2688 		if (work_serial) {
2689 
2690 			if (kt - remote->remotes[i].active_time > WACOM_REMOTE_BATTERY_TIMEOUT
2691 			    && remote->remotes[i].active_time != 0)
2692 				wacom_remote_destroy_battery(wacom, i);
2693 
2694 			if (remote->remotes[i].serial == work_serial) {
2695 				wacom_remote_attach_battery(wacom, i);
2696 				continue;
2697 			}
2698 
2699 			if (remote->remotes[i].serial)
2700 				wacom_remote_destroy_one(wacom, i);
2701 
2702 			wacom_remote_create_one(wacom, work_serial, i);
2703 
2704 		} else if (remote->remotes[i].serial) {
2705 			wacom_remote_destroy_one(wacom, i);
2706 		}
2707 	}
2708 }
2709 
2710 static void wacom_mode_change_work(struct work_struct *work)
2711 {
2712 	struct wacom *wacom = container_of(work, struct wacom, mode_change_work);
2713 	struct wacom_shared *shared = wacom->wacom_wac.shared;
2714 	struct wacom *wacom1 = NULL;
2715 	struct wacom *wacom2 = NULL;
2716 	bool is_direct = wacom->wacom_wac.is_direct_mode;
2717 	int error = 0;
2718 
2719 	if (shared->pen) {
2720 		wacom1 = hid_get_drvdata(shared->pen);
2721 		wacom_release_resources(wacom1);
2722 		hid_hw_stop(wacom1->hdev);
2723 		wacom1->wacom_wac.has_mode_change = true;
2724 		wacom1->wacom_wac.is_direct_mode = is_direct;
2725 	}
2726 
2727 	if (shared->touch) {
2728 		wacom2 = hid_get_drvdata(shared->touch);
2729 		wacom_release_resources(wacom2);
2730 		hid_hw_stop(wacom2->hdev);
2731 		wacom2->wacom_wac.has_mode_change = true;
2732 		wacom2->wacom_wac.is_direct_mode = is_direct;
2733 	}
2734 
2735 	if (wacom1) {
2736 		error = wacom_parse_and_register(wacom1, false);
2737 		if (error)
2738 			return;
2739 	}
2740 
2741 	if (wacom2) {
2742 		error = wacom_parse_and_register(wacom2, false);
2743 		if (error)
2744 			return;
2745 	}
2746 
2747 	return;
2748 }
2749 
2750 static int wacom_probe(struct hid_device *hdev,
2751 		const struct hid_device_id *id)
2752 {
2753 	struct wacom *wacom;
2754 	struct wacom_wac *wacom_wac;
2755 	struct wacom_features *features;
2756 	int error;
2757 
2758 	if (!id->driver_data)
2759 		return -EINVAL;
2760 
2761 	hdev->quirks |= HID_QUIRK_NO_INIT_REPORTS;
2762 
2763 	/* hid-core sets this quirk for the boot interface */
2764 	hdev->quirks &= ~HID_QUIRK_NOGET;
2765 
2766 	wacom = devm_kzalloc(&hdev->dev, sizeof(struct wacom), GFP_KERNEL);
2767 	if (!wacom)
2768 		return -ENOMEM;
2769 
2770 	hid_set_drvdata(hdev, wacom);
2771 	wacom->hdev = hdev;
2772 
2773 	wacom_wac = &wacom->wacom_wac;
2774 	wacom_wac->features = *((struct wacom_features *)id->driver_data);
2775 	features = &wacom_wac->features;
2776 
2777 	if (features->check_for_hid_type && features->hid_type != hdev->type)
2778 		return -ENODEV;
2779 
2780 	error = wacom_devm_kfifo_alloc(wacom);
2781 	if (error)
2782 		return error;
2783 
2784 	wacom_wac->hid_data.inputmode = -1;
2785 	wacom_wac->mode_report = -1;
2786 
2787 	if (hid_is_usb(hdev)) {
2788 		struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
2789 		struct usb_device *dev = interface_to_usbdev(intf);
2790 
2791 		wacom->usbdev = dev;
2792 		wacom->intf = intf;
2793 	}
2794 
2795 	mutex_init(&wacom->lock);
2796 	INIT_DELAYED_WORK(&wacom->init_work, wacom_init_work);
2797 	INIT_WORK(&wacom->wireless_work, wacom_wireless_work);
2798 	INIT_WORK(&wacom->battery_work, wacom_battery_work);
2799 	INIT_WORK(&wacom->remote_work, wacom_remote_work);
2800 	INIT_WORK(&wacom->mode_change_work, wacom_mode_change_work);
2801 	timer_setup(&wacom->idleprox_timer, &wacom_idleprox_timeout, TIMER_DEFERRABLE);
2802 
2803 	/* ask for the report descriptor to be loaded by HID */
2804 	error = hid_parse(hdev);
2805 	if (error) {
2806 		hid_err(hdev, "parse failed\n");
2807 		return error;
2808 	}
2809 
2810 	if (features->type == BOOTLOADER) {
2811 		hid_warn(hdev, "Using device in hidraw-only mode");
2812 		return hid_hw_start(hdev, HID_CONNECT_HIDRAW);
2813 	}
2814 
2815 	error = wacom_parse_and_register(wacom, false);
2816 	if (error)
2817 		return error;
2818 
2819 	if (hdev->bus == BUS_BLUETOOTH) {
2820 		error = device_create_file(&hdev->dev, &dev_attr_speed);
2821 		if (error)
2822 			hid_warn(hdev,
2823 				 "can't create sysfs speed attribute err: %d\n",
2824 				 error);
2825 	}
2826 
2827 	wacom_wac->probe_complete = true;
2828 	return 0;
2829 }
2830 
2831 static void wacom_remove(struct hid_device *hdev)
2832 {
2833 	struct wacom *wacom = hid_get_drvdata(hdev);
2834 	struct wacom_wac *wacom_wac = &wacom->wacom_wac;
2835 	struct wacom_features *features = &wacom_wac->features;
2836 
2837 	if (features->device_type & WACOM_DEVICETYPE_WL_MONITOR)
2838 		hid_hw_close(hdev);
2839 
2840 	hid_hw_stop(hdev);
2841 
2842 	cancel_delayed_work_sync(&wacom->init_work);
2843 	cancel_work_sync(&wacom->wireless_work);
2844 	cancel_work_sync(&wacom->battery_work);
2845 	cancel_work_sync(&wacom->remote_work);
2846 	cancel_work_sync(&wacom->mode_change_work);
2847 	del_timer_sync(&wacom->idleprox_timer);
2848 	if (hdev->bus == BUS_BLUETOOTH)
2849 		device_remove_file(&hdev->dev, &dev_attr_speed);
2850 
2851 	/* make sure we don't trigger the LEDs */
2852 	wacom_led_groups_release(wacom);
2853 
2854 	if (wacom->wacom_wac.features.type != REMOTE)
2855 		wacom_release_resources(wacom);
2856 }
2857 
2858 #ifdef CONFIG_PM
2859 static int wacom_resume(struct hid_device *hdev)
2860 {
2861 	struct wacom *wacom = hid_get_drvdata(hdev);
2862 
2863 	mutex_lock(&wacom->lock);
2864 
2865 	/* switch to wacom mode first */
2866 	_wacom_query_tablet_data(wacom);
2867 	wacom_led_control(wacom);
2868 
2869 	mutex_unlock(&wacom->lock);
2870 
2871 	return 0;
2872 }
2873 
2874 static int wacom_reset_resume(struct hid_device *hdev)
2875 {
2876 	return wacom_resume(hdev);
2877 }
2878 #endif /* CONFIG_PM */
2879 
2880 static struct hid_driver wacom_driver = {
2881 	.name =		"wacom",
2882 	.id_table =	wacom_ids,
2883 	.probe =	wacom_probe,
2884 	.remove =	wacom_remove,
2885 	.report =	wacom_wac_report,
2886 #ifdef CONFIG_PM
2887 	.resume =	wacom_resume,
2888 	.reset_resume =	wacom_reset_resume,
2889 #endif
2890 	.raw_event =	wacom_raw_event,
2891 };
2892 module_hid_driver(wacom_driver);
2893 
2894 MODULE_VERSION(DRIVER_VERSION);
2895 MODULE_AUTHOR(DRIVER_AUTHOR);
2896 MODULE_DESCRIPTION(DRIVER_DESC);
2897 MODULE_LICENSE("GPL");
2898