xref: /openbmc/linux/drivers/hid/usbhid/hid-pidff.c (revision d0b73b48)
1 /*
2  *  Force feedback driver for USB HID PID compliant devices
3  *
4  *  Copyright (c) 2005, 2006 Anssi Hannula <anssi.hannula@gmail.com>
5  */
6 
7 /*
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or
11  * (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21  */
22 
23 /* #define DEBUG */
24 
25 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
26 
27 #include <linux/input.h>
28 #include <linux/slab.h>
29 #include <linux/usb.h>
30 
31 #include <linux/hid.h>
32 
33 #include "usbhid.h"
34 
35 #define	PID_EFFECTS_MAX		64
36 
37 /* Report usage table used to put reports into an array */
38 
39 #define PID_SET_EFFECT		0
40 #define PID_EFFECT_OPERATION	1
41 #define PID_DEVICE_GAIN		2
42 #define PID_POOL		3
43 #define PID_BLOCK_LOAD		4
44 #define PID_BLOCK_FREE		5
45 #define PID_DEVICE_CONTROL	6
46 #define PID_CREATE_NEW_EFFECT	7
47 
48 #define PID_REQUIRED_REPORTS	7
49 
50 #define PID_SET_ENVELOPE	8
51 #define PID_SET_CONDITION	9
52 #define PID_SET_PERIODIC	10
53 #define PID_SET_CONSTANT	11
54 #define PID_SET_RAMP		12
55 static const u8 pidff_reports[] = {
56 	0x21, 0x77, 0x7d, 0x7f, 0x89, 0x90, 0x96, 0xab,
57 	0x5a, 0x5f, 0x6e, 0x73, 0x74
58 };
59 
60 /* device_control is really 0x95, but 0x96 specified as it is the usage of
61 the only field in that report */
62 
63 /* Value usage tables used to put fields and values into arrays */
64 
65 #define PID_EFFECT_BLOCK_INDEX	0
66 
67 #define PID_DURATION		1
68 #define PID_GAIN		2
69 #define PID_TRIGGER_BUTTON	3
70 #define PID_TRIGGER_REPEAT_INT	4
71 #define PID_DIRECTION_ENABLE	5
72 #define PID_START_DELAY		6
73 static const u8 pidff_set_effect[] = {
74 	0x22, 0x50, 0x52, 0x53, 0x54, 0x56, 0xa7
75 };
76 
77 #define PID_ATTACK_LEVEL	1
78 #define PID_ATTACK_TIME		2
79 #define PID_FADE_LEVEL		3
80 #define PID_FADE_TIME		4
81 static const u8 pidff_set_envelope[] = { 0x22, 0x5b, 0x5c, 0x5d, 0x5e };
82 
83 #define PID_PARAM_BLOCK_OFFSET	1
84 #define PID_CP_OFFSET		2
85 #define PID_POS_COEFFICIENT	3
86 #define PID_NEG_COEFFICIENT	4
87 #define PID_POS_SATURATION	5
88 #define PID_NEG_SATURATION	6
89 #define PID_DEAD_BAND		7
90 static const u8 pidff_set_condition[] = {
91 	0x22, 0x23, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65
92 };
93 
94 #define PID_MAGNITUDE		1
95 #define PID_OFFSET		2
96 #define PID_PHASE		3
97 #define PID_PERIOD		4
98 static const u8 pidff_set_periodic[] = { 0x22, 0x70, 0x6f, 0x71, 0x72 };
99 static const u8 pidff_set_constant[] = { 0x22, 0x70 };
100 
101 #define PID_RAMP_START		1
102 #define PID_RAMP_END		2
103 static const u8 pidff_set_ramp[] = { 0x22, 0x75, 0x76 };
104 
105 #define PID_RAM_POOL_AVAILABLE	1
106 static const u8 pidff_block_load[] = { 0x22, 0xac };
107 
108 #define PID_LOOP_COUNT		1
109 static const u8 pidff_effect_operation[] = { 0x22, 0x7c };
110 
111 static const u8 pidff_block_free[] = { 0x22 };
112 
113 #define PID_DEVICE_GAIN_FIELD	0
114 static const u8 pidff_device_gain[] = { 0x7e };
115 
116 #define PID_RAM_POOL_SIZE	0
117 #define PID_SIMULTANEOUS_MAX	1
118 #define PID_DEVICE_MANAGED_POOL	2
119 static const u8 pidff_pool[] = { 0x80, 0x83, 0xa9 };
120 
121 /* Special field key tables used to put special field keys into arrays */
122 
123 #define PID_ENABLE_ACTUATORS	0
124 #define PID_RESET		1
125 static const u8 pidff_device_control[] = { 0x97, 0x9a };
126 
127 #define PID_CONSTANT	0
128 #define PID_RAMP	1
129 #define PID_SQUARE	2
130 #define PID_SINE	3
131 #define PID_TRIANGLE	4
132 #define PID_SAW_UP	5
133 #define PID_SAW_DOWN	6
134 #define PID_SPRING	7
135 #define PID_DAMPER	8
136 #define PID_INERTIA	9
137 #define PID_FRICTION	10
138 static const u8 pidff_effect_types[] = {
139 	0x26, 0x27, 0x30, 0x31, 0x32, 0x33, 0x34,
140 	0x40, 0x41, 0x42, 0x43
141 };
142 
143 #define PID_BLOCK_LOAD_SUCCESS	0
144 #define PID_BLOCK_LOAD_FULL	1
145 static const u8 pidff_block_load_status[] = { 0x8c, 0x8d };
146 
147 #define PID_EFFECT_START	0
148 #define PID_EFFECT_STOP		1
149 static const u8 pidff_effect_operation_status[] = { 0x79, 0x7b };
150 
151 struct pidff_usage {
152 	struct hid_field *field;
153 	s32 *value;
154 };
155 
156 struct pidff_device {
157 	struct hid_device *hid;
158 
159 	struct hid_report *reports[sizeof(pidff_reports)];
160 
161 	struct pidff_usage set_effect[sizeof(pidff_set_effect)];
162 	struct pidff_usage set_envelope[sizeof(pidff_set_envelope)];
163 	struct pidff_usage set_condition[sizeof(pidff_set_condition)];
164 	struct pidff_usage set_periodic[sizeof(pidff_set_periodic)];
165 	struct pidff_usage set_constant[sizeof(pidff_set_constant)];
166 	struct pidff_usage set_ramp[sizeof(pidff_set_ramp)];
167 
168 	struct pidff_usage device_gain[sizeof(pidff_device_gain)];
169 	struct pidff_usage block_load[sizeof(pidff_block_load)];
170 	struct pidff_usage pool[sizeof(pidff_pool)];
171 	struct pidff_usage effect_operation[sizeof(pidff_effect_operation)];
172 	struct pidff_usage block_free[sizeof(pidff_block_free)];
173 
174 	/* Special field is a field that is not composed of
175 	   usage<->value pairs that pidff_usage values are */
176 
177 	/* Special field in create_new_effect */
178 	struct hid_field *create_new_effect_type;
179 
180 	/* Special fields in set_effect */
181 	struct hid_field *set_effect_type;
182 	struct hid_field *effect_direction;
183 
184 	/* Special field in device_control */
185 	struct hid_field *device_control;
186 
187 	/* Special field in block_load */
188 	struct hid_field *block_load_status;
189 
190 	/* Special field in effect_operation */
191 	struct hid_field *effect_operation_status;
192 
193 	int control_id[sizeof(pidff_device_control)];
194 	int type_id[sizeof(pidff_effect_types)];
195 	int status_id[sizeof(pidff_block_load_status)];
196 	int operation_id[sizeof(pidff_effect_operation_status)];
197 
198 	int pid_id[PID_EFFECTS_MAX];
199 };
200 
201 /*
202  * Scale an unsigned value with range 0..max for the given field
203  */
204 static int pidff_rescale(int i, int max, struct hid_field *field)
205 {
206 	return i * (field->logical_maximum - field->logical_minimum) / max +
207 	    field->logical_minimum;
208 }
209 
210 /*
211  * Scale a signed value in range -0x8000..0x7fff for the given field
212  */
213 static int pidff_rescale_signed(int i, struct hid_field *field)
214 {
215 	return i == 0 ? 0 : i >
216 	    0 ? i * field->logical_maximum / 0x7fff : i *
217 	    field->logical_minimum / -0x8000;
218 }
219 
220 static void pidff_set(struct pidff_usage *usage, u16 value)
221 {
222 	usage->value[0] = pidff_rescale(value, 0xffff, usage->field);
223 	pr_debug("calculated from %d to %d\n", value, usage->value[0]);
224 }
225 
226 static void pidff_set_signed(struct pidff_usage *usage, s16 value)
227 {
228 	if (usage->field->logical_minimum < 0)
229 		usage->value[0] = pidff_rescale_signed(value, usage->field);
230 	else {
231 		if (value < 0)
232 			usage->value[0] =
233 			    pidff_rescale(-value, 0x8000, usage->field);
234 		else
235 			usage->value[0] =
236 			    pidff_rescale(value, 0x7fff, usage->field);
237 	}
238 	pr_debug("calculated from %d to %d\n", value, usage->value[0]);
239 }
240 
241 /*
242  * Send envelope report to the device
243  */
244 static void pidff_set_envelope_report(struct pidff_device *pidff,
245 				      struct ff_envelope *envelope)
246 {
247 	pidff->set_envelope[PID_EFFECT_BLOCK_INDEX].value[0] =
248 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
249 
250 	pidff->set_envelope[PID_ATTACK_LEVEL].value[0] =
251 	    pidff_rescale(envelope->attack_level >
252 			  0x7fff ? 0x7fff : envelope->attack_level, 0x7fff,
253 			  pidff->set_envelope[PID_ATTACK_LEVEL].field);
254 	pidff->set_envelope[PID_FADE_LEVEL].value[0] =
255 	    pidff_rescale(envelope->fade_level >
256 			  0x7fff ? 0x7fff : envelope->fade_level, 0x7fff,
257 			  pidff->set_envelope[PID_FADE_LEVEL].field);
258 
259 	pidff->set_envelope[PID_ATTACK_TIME].value[0] = envelope->attack_length;
260 	pidff->set_envelope[PID_FADE_TIME].value[0] = envelope->fade_length;
261 
262 	hid_dbg(pidff->hid, "attack %u => %d\n",
263 		envelope->attack_level,
264 		pidff->set_envelope[PID_ATTACK_LEVEL].value[0]);
265 
266 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_ENVELOPE],
267 			  USB_DIR_OUT);
268 }
269 
270 /*
271  * Test if the new envelope differs from old one
272  */
273 static int pidff_needs_set_envelope(struct ff_envelope *envelope,
274 				    struct ff_envelope *old)
275 {
276 	return envelope->attack_level != old->attack_level ||
277 	       envelope->fade_level != old->fade_level ||
278 	       envelope->attack_length != old->attack_length ||
279 	       envelope->fade_length != old->fade_length;
280 }
281 
282 /*
283  * Send constant force report to the device
284  */
285 static void pidff_set_constant_force_report(struct pidff_device *pidff,
286 					    struct ff_effect *effect)
287 {
288 	pidff->set_constant[PID_EFFECT_BLOCK_INDEX].value[0] =
289 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
290 	pidff_set_signed(&pidff->set_constant[PID_MAGNITUDE],
291 			 effect->u.constant.level);
292 
293 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_CONSTANT],
294 			  USB_DIR_OUT);
295 }
296 
297 /*
298  * Test if the constant parameters have changed between effects
299  */
300 static int pidff_needs_set_constant(struct ff_effect *effect,
301 				    struct ff_effect *old)
302 {
303 	return effect->u.constant.level != old->u.constant.level;
304 }
305 
306 /*
307  * Send set effect report to the device
308  */
309 static void pidff_set_effect_report(struct pidff_device *pidff,
310 				    struct ff_effect *effect)
311 {
312 	pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
313 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
314 	pidff->set_effect_type->value[0] =
315 		pidff->create_new_effect_type->value[0];
316 	pidff->set_effect[PID_DURATION].value[0] = effect->replay.length;
317 	pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = effect->trigger.button;
318 	pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] =
319 		effect->trigger.interval;
320 	pidff->set_effect[PID_GAIN].value[0] =
321 		pidff->set_effect[PID_GAIN].field->logical_maximum;
322 	pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
323 	pidff->effect_direction->value[0] =
324 		pidff_rescale(effect->direction, 0xffff,
325 				pidff->effect_direction);
326 	pidff->set_effect[PID_START_DELAY].value[0] = effect->replay.delay;
327 
328 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
329 			  USB_DIR_OUT);
330 }
331 
332 /*
333  * Test if the values used in set_effect have changed
334  */
335 static int pidff_needs_set_effect(struct ff_effect *effect,
336 				  struct ff_effect *old)
337 {
338 	return effect->replay.length != old->replay.length ||
339 	       effect->trigger.interval != old->trigger.interval ||
340 	       effect->trigger.button != old->trigger.button ||
341 	       effect->direction != old->direction ||
342 	       effect->replay.delay != old->replay.delay;
343 }
344 
345 /*
346  * Send periodic effect report to the device
347  */
348 static void pidff_set_periodic_report(struct pidff_device *pidff,
349 				      struct ff_effect *effect)
350 {
351 	pidff->set_periodic[PID_EFFECT_BLOCK_INDEX].value[0] =
352 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
353 	pidff_set_signed(&pidff->set_periodic[PID_MAGNITUDE],
354 			 effect->u.periodic.magnitude);
355 	pidff_set_signed(&pidff->set_periodic[PID_OFFSET],
356 			 effect->u.periodic.offset);
357 	pidff_set(&pidff->set_periodic[PID_PHASE], effect->u.periodic.phase);
358 	pidff->set_periodic[PID_PERIOD].value[0] = effect->u.periodic.period;
359 
360 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_PERIODIC],
361 			  USB_DIR_OUT);
362 
363 }
364 
365 /*
366  * Test if periodic effect parameters have changed
367  */
368 static int pidff_needs_set_periodic(struct ff_effect *effect,
369 				    struct ff_effect *old)
370 {
371 	return effect->u.periodic.magnitude != old->u.periodic.magnitude ||
372 	       effect->u.periodic.offset != old->u.periodic.offset ||
373 	       effect->u.periodic.phase != old->u.periodic.phase ||
374 	       effect->u.periodic.period != old->u.periodic.period;
375 }
376 
377 /*
378  * Send condition effect reports to the device
379  */
380 static void pidff_set_condition_report(struct pidff_device *pidff,
381 				       struct ff_effect *effect)
382 {
383 	int i;
384 
385 	pidff->set_condition[PID_EFFECT_BLOCK_INDEX].value[0] =
386 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
387 
388 	for (i = 0; i < 2; i++) {
389 		pidff->set_condition[PID_PARAM_BLOCK_OFFSET].value[0] = i;
390 		pidff_set_signed(&pidff->set_condition[PID_CP_OFFSET],
391 				 effect->u.condition[i].center);
392 		pidff_set_signed(&pidff->set_condition[PID_POS_COEFFICIENT],
393 				 effect->u.condition[i].right_coeff);
394 		pidff_set_signed(&pidff->set_condition[PID_NEG_COEFFICIENT],
395 				 effect->u.condition[i].left_coeff);
396 		pidff_set(&pidff->set_condition[PID_POS_SATURATION],
397 			  effect->u.condition[i].right_saturation);
398 		pidff_set(&pidff->set_condition[PID_NEG_SATURATION],
399 			  effect->u.condition[i].left_saturation);
400 		pidff_set(&pidff->set_condition[PID_DEAD_BAND],
401 			  effect->u.condition[i].deadband);
402 		usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_CONDITION],
403 				  USB_DIR_OUT);
404 	}
405 }
406 
407 /*
408  * Test if condition effect parameters have changed
409  */
410 static int pidff_needs_set_condition(struct ff_effect *effect,
411 				     struct ff_effect *old)
412 {
413 	int i;
414 	int ret = 0;
415 
416 	for (i = 0; i < 2; i++) {
417 		struct ff_condition_effect *cond = &effect->u.condition[i];
418 		struct ff_condition_effect *old_cond = &old->u.condition[i];
419 
420 		ret |= cond->center != old_cond->center ||
421 		       cond->right_coeff != old_cond->right_coeff ||
422 		       cond->left_coeff != old_cond->left_coeff ||
423 		       cond->right_saturation != old_cond->right_saturation ||
424 		       cond->left_saturation != old_cond->left_saturation ||
425 		       cond->deadband != old_cond->deadband;
426 	}
427 
428 	return ret;
429 }
430 
431 /*
432  * Send ramp force report to the device
433  */
434 static void pidff_set_ramp_force_report(struct pidff_device *pidff,
435 					struct ff_effect *effect)
436 {
437 	pidff->set_ramp[PID_EFFECT_BLOCK_INDEX].value[0] =
438 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
439 	pidff_set_signed(&pidff->set_ramp[PID_RAMP_START],
440 			 effect->u.ramp.start_level);
441 	pidff_set_signed(&pidff->set_ramp[PID_RAMP_END],
442 			 effect->u.ramp.end_level);
443 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_RAMP],
444 			  USB_DIR_OUT);
445 }
446 
447 /*
448  * Test if ramp force parameters have changed
449  */
450 static int pidff_needs_set_ramp(struct ff_effect *effect, struct ff_effect *old)
451 {
452 	return effect->u.ramp.start_level != old->u.ramp.start_level ||
453 	       effect->u.ramp.end_level != old->u.ramp.end_level;
454 }
455 
456 /*
457  * Send a request for effect upload to the device
458  *
459  * Returns 0 if device reported success, -ENOSPC if the device reported memory
460  * is full. Upon unknown response the function will retry for 60 times, if
461  * still unsuccessful -EIO is returned.
462  */
463 static int pidff_request_effect_upload(struct pidff_device *pidff, int efnum)
464 {
465 	int j;
466 
467 	pidff->create_new_effect_type->value[0] = efnum;
468 	usbhid_submit_report(pidff->hid, pidff->reports[PID_CREATE_NEW_EFFECT],
469 			  USB_DIR_OUT);
470 	hid_dbg(pidff->hid, "create_new_effect sent, type: %d\n", efnum);
471 
472 	pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] = 0;
473 	pidff->block_load_status->value[0] = 0;
474 	usbhid_wait_io(pidff->hid);
475 
476 	for (j = 0; j < 60; j++) {
477 		hid_dbg(pidff->hid, "pid_block_load requested\n");
478 		usbhid_submit_report(pidff->hid, pidff->reports[PID_BLOCK_LOAD],
479 				  USB_DIR_IN);
480 		usbhid_wait_io(pidff->hid);
481 		if (pidff->block_load_status->value[0] ==
482 		    pidff->status_id[PID_BLOCK_LOAD_SUCCESS]) {
483 			hid_dbg(pidff->hid, "device reported free memory: %d bytes\n",
484 				 pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
485 				 pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
486 			return 0;
487 		}
488 		if (pidff->block_load_status->value[0] ==
489 		    pidff->status_id[PID_BLOCK_LOAD_FULL]) {
490 			hid_dbg(pidff->hid, "not enough memory free: %d bytes\n",
491 				pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
492 				pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
493 			return -ENOSPC;
494 		}
495 	}
496 	hid_err(pidff->hid, "pid_block_load failed 60 times\n");
497 	return -EIO;
498 }
499 
500 /*
501  * Play the effect with PID id n times
502  */
503 static void pidff_playback_pid(struct pidff_device *pidff, int pid_id, int n)
504 {
505 	pidff->effect_operation[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
506 
507 	if (n == 0) {
508 		pidff->effect_operation_status->value[0] =
509 			pidff->operation_id[PID_EFFECT_STOP];
510 	} else {
511 		pidff->effect_operation_status->value[0] =
512 			pidff->operation_id[PID_EFFECT_START];
513 		pidff->effect_operation[PID_LOOP_COUNT].value[0] = n;
514 	}
515 
516 	usbhid_submit_report(pidff->hid, pidff->reports[PID_EFFECT_OPERATION],
517 			  USB_DIR_OUT);
518 }
519 
520 /**
521  * Play the effect with effect id @effect_id for @value times
522  */
523 static int pidff_playback(struct input_dev *dev, int effect_id, int value)
524 {
525 	struct pidff_device *pidff = dev->ff->private;
526 
527 	pidff_playback_pid(pidff, pidff->pid_id[effect_id], value);
528 
529 	return 0;
530 }
531 
532 /*
533  * Erase effect with PID id
534  */
535 static void pidff_erase_pid(struct pidff_device *pidff, int pid_id)
536 {
537 	pidff->block_free[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
538 	usbhid_submit_report(pidff->hid, pidff->reports[PID_BLOCK_FREE],
539 			  USB_DIR_OUT);
540 }
541 
542 /*
543  * Stop and erase effect with effect_id
544  */
545 static int pidff_erase_effect(struct input_dev *dev, int effect_id)
546 {
547 	struct pidff_device *pidff = dev->ff->private;
548 	int pid_id = pidff->pid_id[effect_id];
549 
550 	hid_dbg(pidff->hid, "starting to erase %d/%d\n",
551 		effect_id, pidff->pid_id[effect_id]);
552 	/* Wait for the queue to clear. We do not want a full fifo to
553 	   prevent the effect removal. */
554 	usbhid_wait_io(pidff->hid);
555 	pidff_playback_pid(pidff, pid_id, 0);
556 	pidff_erase_pid(pidff, pid_id);
557 
558 	return 0;
559 }
560 
561 /*
562  * Effect upload handler
563  */
564 static int pidff_upload_effect(struct input_dev *dev, struct ff_effect *effect,
565 			       struct ff_effect *old)
566 {
567 	struct pidff_device *pidff = dev->ff->private;
568 	int type_id;
569 	int error;
570 
571 	switch (effect->type) {
572 	case FF_CONSTANT:
573 		if (!old) {
574 			error = pidff_request_effect_upload(pidff,
575 					pidff->type_id[PID_CONSTANT]);
576 			if (error)
577 				return error;
578 		}
579 		if (!old || pidff_needs_set_effect(effect, old))
580 			pidff_set_effect_report(pidff, effect);
581 		if (!old || pidff_needs_set_constant(effect, old))
582 			pidff_set_constant_force_report(pidff, effect);
583 		if (!old ||
584 		    pidff_needs_set_envelope(&effect->u.constant.envelope,
585 					&old->u.constant.envelope))
586 			pidff_set_envelope_report(pidff,
587 					&effect->u.constant.envelope);
588 		break;
589 
590 	case FF_PERIODIC:
591 		if (!old) {
592 			switch (effect->u.periodic.waveform) {
593 			case FF_SQUARE:
594 				type_id = PID_SQUARE;
595 				break;
596 			case FF_TRIANGLE:
597 				type_id = PID_TRIANGLE;
598 				break;
599 			case FF_SINE:
600 				type_id = PID_SINE;
601 				break;
602 			case FF_SAW_UP:
603 				type_id = PID_SAW_UP;
604 				break;
605 			case FF_SAW_DOWN:
606 				type_id = PID_SAW_DOWN;
607 				break;
608 			default:
609 				hid_err(pidff->hid, "invalid waveform\n");
610 				return -EINVAL;
611 			}
612 
613 			error = pidff_request_effect_upload(pidff,
614 					pidff->type_id[type_id]);
615 			if (error)
616 				return error;
617 		}
618 		if (!old || pidff_needs_set_effect(effect, old))
619 			pidff_set_effect_report(pidff, effect);
620 		if (!old || pidff_needs_set_periodic(effect, old))
621 			pidff_set_periodic_report(pidff, effect);
622 		if (!old ||
623 		    pidff_needs_set_envelope(&effect->u.periodic.envelope,
624 					&old->u.periodic.envelope))
625 			pidff_set_envelope_report(pidff,
626 					&effect->u.periodic.envelope);
627 		break;
628 
629 	case FF_RAMP:
630 		if (!old) {
631 			error = pidff_request_effect_upload(pidff,
632 					pidff->type_id[PID_RAMP]);
633 			if (error)
634 				return error;
635 		}
636 		if (!old || pidff_needs_set_effect(effect, old))
637 			pidff_set_effect_report(pidff, effect);
638 		if (!old || pidff_needs_set_ramp(effect, old))
639 			pidff_set_ramp_force_report(pidff, effect);
640 		if (!old ||
641 		    pidff_needs_set_envelope(&effect->u.ramp.envelope,
642 					&old->u.ramp.envelope))
643 			pidff_set_envelope_report(pidff,
644 					&effect->u.ramp.envelope);
645 		break;
646 
647 	case FF_SPRING:
648 		if (!old) {
649 			error = pidff_request_effect_upload(pidff,
650 					pidff->type_id[PID_SPRING]);
651 			if (error)
652 				return error;
653 		}
654 		if (!old || pidff_needs_set_effect(effect, old))
655 			pidff_set_effect_report(pidff, effect);
656 		if (!old || pidff_needs_set_condition(effect, old))
657 			pidff_set_condition_report(pidff, effect);
658 		break;
659 
660 	case FF_FRICTION:
661 		if (!old) {
662 			error = pidff_request_effect_upload(pidff,
663 					pidff->type_id[PID_FRICTION]);
664 			if (error)
665 				return error;
666 		}
667 		if (!old || pidff_needs_set_effect(effect, old))
668 			pidff_set_effect_report(pidff, effect);
669 		if (!old || pidff_needs_set_condition(effect, old))
670 			pidff_set_condition_report(pidff, effect);
671 		break;
672 
673 	case FF_DAMPER:
674 		if (!old) {
675 			error = pidff_request_effect_upload(pidff,
676 					pidff->type_id[PID_DAMPER]);
677 			if (error)
678 				return error;
679 		}
680 		if (!old || pidff_needs_set_effect(effect, old))
681 			pidff_set_effect_report(pidff, effect);
682 		if (!old || pidff_needs_set_condition(effect, old))
683 			pidff_set_condition_report(pidff, effect);
684 		break;
685 
686 	case FF_INERTIA:
687 		if (!old) {
688 			error = pidff_request_effect_upload(pidff,
689 					pidff->type_id[PID_INERTIA]);
690 			if (error)
691 				return error;
692 		}
693 		if (!old || pidff_needs_set_effect(effect, old))
694 			pidff_set_effect_report(pidff, effect);
695 		if (!old || pidff_needs_set_condition(effect, old))
696 			pidff_set_condition_report(pidff, effect);
697 		break;
698 
699 	default:
700 		hid_err(pidff->hid, "invalid type\n");
701 		return -EINVAL;
702 	}
703 
704 	if (!old)
705 		pidff->pid_id[effect->id] =
706 		    pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
707 
708 	hid_dbg(pidff->hid, "uploaded\n");
709 
710 	return 0;
711 }
712 
713 /*
714  * set_gain() handler
715  */
716 static void pidff_set_gain(struct input_dev *dev, u16 gain)
717 {
718 	struct pidff_device *pidff = dev->ff->private;
719 
720 	pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], gain);
721 	usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
722 			  USB_DIR_OUT);
723 }
724 
725 static void pidff_autocenter(struct pidff_device *pidff, u16 magnitude)
726 {
727 	struct hid_field *field =
728 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].field;
729 
730 	if (!magnitude) {
731 		pidff_playback_pid(pidff, field->logical_minimum, 0);
732 		return;
733 	}
734 
735 	pidff_playback_pid(pidff, field->logical_minimum, 1);
736 
737 	pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
738 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum;
739 	pidff->set_effect_type->value[0] = pidff->type_id[PID_SPRING];
740 	pidff->set_effect[PID_DURATION].value[0] = 0;
741 	pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = 0;
742 	pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] = 0;
743 	pidff_set(&pidff->set_effect[PID_GAIN], magnitude);
744 	pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
745 	pidff->set_effect[PID_START_DELAY].value[0] = 0;
746 
747 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
748 			  USB_DIR_OUT);
749 }
750 
751 /*
752  * pidff_set_autocenter() handler
753  */
754 static void pidff_set_autocenter(struct input_dev *dev, u16 magnitude)
755 {
756 	struct pidff_device *pidff = dev->ff->private;
757 
758 	pidff_autocenter(pidff, magnitude);
759 }
760 
761 /*
762  * Find fields from a report and fill a pidff_usage
763  */
764 static int pidff_find_fields(struct pidff_usage *usage, const u8 *table,
765 			     struct hid_report *report, int count, int strict)
766 {
767 	int i, j, k, found;
768 
769 	for (k = 0; k < count; k++) {
770 		found = 0;
771 		for (i = 0; i < report->maxfield; i++) {
772 			if (report->field[i]->maxusage !=
773 			    report->field[i]->report_count) {
774 				pr_debug("maxusage and report_count do not match, skipping\n");
775 				continue;
776 			}
777 			for (j = 0; j < report->field[i]->maxusage; j++) {
778 				if (report->field[i]->usage[j].hid ==
779 				    (HID_UP_PID | table[k])) {
780 					pr_debug("found %d at %d->%d\n",
781 						 k, i, j);
782 					usage[k].field = report->field[i];
783 					usage[k].value =
784 						&report->field[i]->value[j];
785 					found = 1;
786 					break;
787 				}
788 			}
789 			if (found)
790 				break;
791 		}
792 		if (!found && strict) {
793 			pr_debug("failed to locate %d\n", k);
794 			return -1;
795 		}
796 	}
797 	return 0;
798 }
799 
800 /*
801  * Return index into pidff_reports for the given usage
802  */
803 static int pidff_check_usage(int usage)
804 {
805 	int i;
806 
807 	for (i = 0; i < sizeof(pidff_reports); i++)
808 		if (usage == (HID_UP_PID | pidff_reports[i]))
809 			return i;
810 
811 	return -1;
812 }
813 
814 /*
815  * Find the reports and fill pidff->reports[]
816  * report_type specifies either OUTPUT or FEATURE reports
817  */
818 static void pidff_find_reports(struct hid_device *hid, int report_type,
819 			       struct pidff_device *pidff)
820 {
821 	struct hid_report *report;
822 	int i, ret;
823 
824 	list_for_each_entry(report,
825 			    &hid->report_enum[report_type].report_list, list) {
826 		if (report->maxfield < 1)
827 			continue;
828 		ret = pidff_check_usage(report->field[0]->logical);
829 		if (ret != -1) {
830 			hid_dbg(hid, "found usage 0x%02x from field->logical\n",
831 				pidff_reports[ret]);
832 			pidff->reports[ret] = report;
833 			continue;
834 		}
835 
836 		/*
837 		 * Sometimes logical collections are stacked to indicate
838 		 * different usages for the report and the field, in which
839 		 * case we want the usage of the parent. However, Linux HID
840 		 * implementation hides this fact, so we have to dig it up
841 		 * ourselves
842 		 */
843 		i = report->field[0]->usage[0].collection_index;
844 		if (i <= 0 ||
845 		    hid->collection[i - 1].type != HID_COLLECTION_LOGICAL)
846 			continue;
847 		ret = pidff_check_usage(hid->collection[i - 1].usage);
848 		if (ret != -1 && !pidff->reports[ret]) {
849 			hid_dbg(hid,
850 				"found usage 0x%02x from collection array\n",
851 				pidff_reports[ret]);
852 			pidff->reports[ret] = report;
853 		}
854 	}
855 }
856 
857 /*
858  * Test if the required reports have been found
859  */
860 static int pidff_reports_ok(struct pidff_device *pidff)
861 {
862 	int i;
863 
864 	for (i = 0; i <= PID_REQUIRED_REPORTS; i++) {
865 		if (!pidff->reports[i]) {
866 			hid_dbg(pidff->hid, "%d missing\n", i);
867 			return 0;
868 		}
869 	}
870 
871 	return 1;
872 }
873 
874 /*
875  * Find a field with a specific usage within a report
876  */
877 static struct hid_field *pidff_find_special_field(struct hid_report *report,
878 						  int usage, int enforce_min)
879 {
880 	int i;
881 
882 	for (i = 0; i < report->maxfield; i++) {
883 		if (report->field[i]->logical == (HID_UP_PID | usage) &&
884 		    report->field[i]->report_count > 0) {
885 			if (!enforce_min ||
886 			    report->field[i]->logical_minimum == 1)
887 				return report->field[i];
888 			else {
889 				pr_err("logical_minimum is not 1 as it should be\n");
890 				return NULL;
891 			}
892 		}
893 	}
894 	return NULL;
895 }
896 
897 /*
898  * Fill a pidff->*_id struct table
899  */
900 static int pidff_find_special_keys(int *keys, struct hid_field *fld,
901 				   const u8 *usagetable, int count)
902 {
903 
904 	int i, j;
905 	int found = 0;
906 
907 	for (i = 0; i < count; i++) {
908 		for (j = 0; j < fld->maxusage; j++) {
909 			if (fld->usage[j].hid == (HID_UP_PID | usagetable[i])) {
910 				keys[i] = j + 1;
911 				found++;
912 				break;
913 			}
914 		}
915 	}
916 	return found;
917 }
918 
919 #define PIDFF_FIND_SPECIAL_KEYS(keys, field, name) \
920 	pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
921 		sizeof(pidff_ ## name))
922 
923 /*
924  * Find and check the special fields
925  */
926 static int pidff_find_special_fields(struct pidff_device *pidff)
927 {
928 	hid_dbg(pidff->hid, "finding special fields\n");
929 
930 	pidff->create_new_effect_type =
931 		pidff_find_special_field(pidff->reports[PID_CREATE_NEW_EFFECT],
932 					 0x25, 1);
933 	pidff->set_effect_type =
934 		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
935 					 0x25, 1);
936 	pidff->effect_direction =
937 		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
938 					 0x57, 0);
939 	pidff->device_control =
940 		pidff_find_special_field(pidff->reports[PID_DEVICE_CONTROL],
941 					 0x96, 1);
942 	pidff->block_load_status =
943 		pidff_find_special_field(pidff->reports[PID_BLOCK_LOAD],
944 					 0x8b, 1);
945 	pidff->effect_operation_status =
946 		pidff_find_special_field(pidff->reports[PID_EFFECT_OPERATION],
947 					 0x78, 1);
948 
949 	hid_dbg(pidff->hid, "search done\n");
950 
951 	if (!pidff->create_new_effect_type || !pidff->set_effect_type) {
952 		hid_err(pidff->hid, "effect lists not found\n");
953 		return -1;
954 	}
955 
956 	if (!pidff->effect_direction) {
957 		hid_err(pidff->hid, "direction field not found\n");
958 		return -1;
959 	}
960 
961 	if (!pidff->device_control) {
962 		hid_err(pidff->hid, "device control field not found\n");
963 		return -1;
964 	}
965 
966 	if (!pidff->block_load_status) {
967 		hid_err(pidff->hid, "block load status field not found\n");
968 		return -1;
969 	}
970 
971 	if (!pidff->effect_operation_status) {
972 		hid_err(pidff->hid, "effect operation field not found\n");
973 		return -1;
974 	}
975 
976 	pidff_find_special_keys(pidff->control_id, pidff->device_control,
977 				pidff_device_control,
978 				sizeof(pidff_device_control));
979 
980 	PIDFF_FIND_SPECIAL_KEYS(control_id, device_control, device_control);
981 
982 	if (!PIDFF_FIND_SPECIAL_KEYS(type_id, create_new_effect_type,
983 				     effect_types)) {
984 		hid_err(pidff->hid, "no effect types found\n");
985 		return -1;
986 	}
987 
988 	if (PIDFF_FIND_SPECIAL_KEYS(status_id, block_load_status,
989 				    block_load_status) !=
990 			sizeof(pidff_block_load_status)) {
991 		hid_err(pidff->hid,
992 			"block load status identifiers not found\n");
993 		return -1;
994 	}
995 
996 	if (PIDFF_FIND_SPECIAL_KEYS(operation_id, effect_operation_status,
997 				    effect_operation_status) !=
998 			sizeof(pidff_effect_operation_status)) {
999 		hid_err(pidff->hid, "effect operation identifiers not found\n");
1000 		return -1;
1001 	}
1002 
1003 	return 0;
1004 }
1005 
1006 /**
1007  * Find the implemented effect types
1008  */
1009 static int pidff_find_effects(struct pidff_device *pidff,
1010 			      struct input_dev *dev)
1011 {
1012 	int i;
1013 
1014 	for (i = 0; i < sizeof(pidff_effect_types); i++) {
1015 		int pidff_type = pidff->type_id[i];
1016 		if (pidff->set_effect_type->usage[pidff_type].hid !=
1017 		    pidff->create_new_effect_type->usage[pidff_type].hid) {
1018 			hid_err(pidff->hid,
1019 				"effect type number %d is invalid\n", i);
1020 			return -1;
1021 		}
1022 	}
1023 
1024 	if (pidff->type_id[PID_CONSTANT])
1025 		set_bit(FF_CONSTANT, dev->ffbit);
1026 	if (pidff->type_id[PID_RAMP])
1027 		set_bit(FF_RAMP, dev->ffbit);
1028 	if (pidff->type_id[PID_SQUARE]) {
1029 		set_bit(FF_SQUARE, dev->ffbit);
1030 		set_bit(FF_PERIODIC, dev->ffbit);
1031 	}
1032 	if (pidff->type_id[PID_SINE]) {
1033 		set_bit(FF_SINE, dev->ffbit);
1034 		set_bit(FF_PERIODIC, dev->ffbit);
1035 	}
1036 	if (pidff->type_id[PID_TRIANGLE]) {
1037 		set_bit(FF_TRIANGLE, dev->ffbit);
1038 		set_bit(FF_PERIODIC, dev->ffbit);
1039 	}
1040 	if (pidff->type_id[PID_SAW_UP]) {
1041 		set_bit(FF_SAW_UP, dev->ffbit);
1042 		set_bit(FF_PERIODIC, dev->ffbit);
1043 	}
1044 	if (pidff->type_id[PID_SAW_DOWN]) {
1045 		set_bit(FF_SAW_DOWN, dev->ffbit);
1046 		set_bit(FF_PERIODIC, dev->ffbit);
1047 	}
1048 	if (pidff->type_id[PID_SPRING])
1049 		set_bit(FF_SPRING, dev->ffbit);
1050 	if (pidff->type_id[PID_DAMPER])
1051 		set_bit(FF_DAMPER, dev->ffbit);
1052 	if (pidff->type_id[PID_INERTIA])
1053 		set_bit(FF_INERTIA, dev->ffbit);
1054 	if (pidff->type_id[PID_FRICTION])
1055 		set_bit(FF_FRICTION, dev->ffbit);
1056 
1057 	return 0;
1058 
1059 }
1060 
1061 #define PIDFF_FIND_FIELDS(name, report, strict) \
1062 	pidff_find_fields(pidff->name, pidff_ ## name, \
1063 		pidff->reports[report], \
1064 		sizeof(pidff_ ## name), strict)
1065 
1066 /*
1067  * Fill and check the pidff_usages
1068  */
1069 static int pidff_init_fields(struct pidff_device *pidff, struct input_dev *dev)
1070 {
1071 	int envelope_ok = 0;
1072 
1073 	if (PIDFF_FIND_FIELDS(set_effect, PID_SET_EFFECT, 1)) {
1074 		hid_err(pidff->hid, "unknown set_effect report layout\n");
1075 		return -ENODEV;
1076 	}
1077 
1078 	PIDFF_FIND_FIELDS(block_load, PID_BLOCK_LOAD, 0);
1079 	if (!pidff->block_load[PID_EFFECT_BLOCK_INDEX].value) {
1080 		hid_err(pidff->hid, "unknown pid_block_load report layout\n");
1081 		return -ENODEV;
1082 	}
1083 
1084 	if (PIDFF_FIND_FIELDS(effect_operation, PID_EFFECT_OPERATION, 1)) {
1085 		hid_err(pidff->hid, "unknown effect_operation report layout\n");
1086 		return -ENODEV;
1087 	}
1088 
1089 	if (PIDFF_FIND_FIELDS(block_free, PID_BLOCK_FREE, 1)) {
1090 		hid_err(pidff->hid, "unknown pid_block_free report layout\n");
1091 		return -ENODEV;
1092 	}
1093 
1094 	if (!PIDFF_FIND_FIELDS(set_envelope, PID_SET_ENVELOPE, 1))
1095 		envelope_ok = 1;
1096 
1097 	if (pidff_find_special_fields(pidff) || pidff_find_effects(pidff, dev))
1098 		return -ENODEV;
1099 
1100 	if (!envelope_ok) {
1101 		if (test_and_clear_bit(FF_CONSTANT, dev->ffbit))
1102 			hid_warn(pidff->hid,
1103 				 "has constant effect but no envelope\n");
1104 		if (test_and_clear_bit(FF_RAMP, dev->ffbit))
1105 			hid_warn(pidff->hid,
1106 				 "has ramp effect but no envelope\n");
1107 
1108 		if (test_and_clear_bit(FF_PERIODIC, dev->ffbit))
1109 			hid_warn(pidff->hid,
1110 				 "has periodic effect but no envelope\n");
1111 	}
1112 
1113 	if (test_bit(FF_CONSTANT, dev->ffbit) &&
1114 	    PIDFF_FIND_FIELDS(set_constant, PID_SET_CONSTANT, 1)) {
1115 		hid_warn(pidff->hid, "unknown constant effect layout\n");
1116 		clear_bit(FF_CONSTANT, dev->ffbit);
1117 	}
1118 
1119 	if (test_bit(FF_RAMP, dev->ffbit) &&
1120 	    PIDFF_FIND_FIELDS(set_ramp, PID_SET_RAMP, 1)) {
1121 		hid_warn(pidff->hid, "unknown ramp effect layout\n");
1122 		clear_bit(FF_RAMP, dev->ffbit);
1123 	}
1124 
1125 	if ((test_bit(FF_SPRING, dev->ffbit) ||
1126 	     test_bit(FF_DAMPER, dev->ffbit) ||
1127 	     test_bit(FF_FRICTION, dev->ffbit) ||
1128 	     test_bit(FF_INERTIA, dev->ffbit)) &&
1129 	    PIDFF_FIND_FIELDS(set_condition, PID_SET_CONDITION, 1)) {
1130 		hid_warn(pidff->hid, "unknown condition effect layout\n");
1131 		clear_bit(FF_SPRING, dev->ffbit);
1132 		clear_bit(FF_DAMPER, dev->ffbit);
1133 		clear_bit(FF_FRICTION, dev->ffbit);
1134 		clear_bit(FF_INERTIA, dev->ffbit);
1135 	}
1136 
1137 	if (test_bit(FF_PERIODIC, dev->ffbit) &&
1138 	    PIDFF_FIND_FIELDS(set_periodic, PID_SET_PERIODIC, 1)) {
1139 		hid_warn(pidff->hid, "unknown periodic effect layout\n");
1140 		clear_bit(FF_PERIODIC, dev->ffbit);
1141 	}
1142 
1143 	PIDFF_FIND_FIELDS(pool, PID_POOL, 0);
1144 
1145 	if (!PIDFF_FIND_FIELDS(device_gain, PID_DEVICE_GAIN, 1))
1146 		set_bit(FF_GAIN, dev->ffbit);
1147 
1148 	return 0;
1149 }
1150 
1151 /*
1152  * Reset the device
1153  */
1154 static void pidff_reset(struct pidff_device *pidff)
1155 {
1156 	struct hid_device *hid = pidff->hid;
1157 	int i = 0;
1158 
1159 	pidff->device_control->value[0] = pidff->control_id[PID_RESET];
1160 	/* We reset twice as sometimes hid_wait_io isn't waiting long enough */
1161 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1162 	usbhid_wait_io(hid);
1163 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1164 	usbhid_wait_io(hid);
1165 
1166 	pidff->device_control->value[0] =
1167 		pidff->control_id[PID_ENABLE_ACTUATORS];
1168 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1169 	usbhid_wait_io(hid);
1170 
1171 	/* pool report is sometimes messed up, refetch it */
1172 	usbhid_submit_report(hid, pidff->reports[PID_POOL], USB_DIR_IN);
1173 	usbhid_wait_io(hid);
1174 
1175 	if (pidff->pool[PID_SIMULTANEOUS_MAX].value) {
1176 		while (pidff->pool[PID_SIMULTANEOUS_MAX].value[0] < 2) {
1177 			if (i++ > 20) {
1178 				hid_warn(pidff->hid,
1179 					 "device reports %d simultaneous effects\n",
1180 					 pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);
1181 				break;
1182 			}
1183 			hid_dbg(pidff->hid, "pid_pool requested again\n");
1184 			usbhid_submit_report(hid, pidff->reports[PID_POOL],
1185 					  USB_DIR_IN);
1186 			usbhid_wait_io(hid);
1187 		}
1188 	}
1189 }
1190 
1191 /*
1192  * Test if autocenter modification is using the supported method
1193  */
1194 static int pidff_check_autocenter(struct pidff_device *pidff,
1195 				  struct input_dev *dev)
1196 {
1197 	int error;
1198 
1199 	/*
1200 	 * Let's find out if autocenter modification is supported
1201 	 * Specification doesn't specify anything, so we request an
1202 	 * effect upload and cancel it immediately. If the approved
1203 	 * effect id was one above the minimum, then we assume the first
1204 	 * effect id is a built-in spring type effect used for autocenter
1205 	 */
1206 
1207 	error = pidff_request_effect_upload(pidff, 1);
1208 	if (error) {
1209 		hid_err(pidff->hid, "upload request failed\n");
1210 		return error;
1211 	}
1212 
1213 	if (pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] ==
1214 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum + 1) {
1215 		pidff_autocenter(pidff, 0xffff);
1216 		set_bit(FF_AUTOCENTER, dev->ffbit);
1217 	} else {
1218 		hid_notice(pidff->hid,
1219 			   "device has unknown autocenter control method\n");
1220 	}
1221 
1222 	pidff_erase_pid(pidff,
1223 			pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0]);
1224 
1225 	return 0;
1226 
1227 }
1228 
1229 /*
1230  * Check if the device is PID and initialize it
1231  */
1232 int hid_pidff_init(struct hid_device *hid)
1233 {
1234 	struct pidff_device *pidff;
1235 	struct hid_input *hidinput = list_entry(hid->inputs.next,
1236 						struct hid_input, list);
1237 	struct input_dev *dev = hidinput->input;
1238 	struct ff_device *ff;
1239 	int max_effects;
1240 	int error;
1241 
1242 	hid_dbg(hid, "starting pid init\n");
1243 
1244 	if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {
1245 		hid_dbg(hid, "not a PID device, no output report\n");
1246 		return -ENODEV;
1247 	}
1248 
1249 	pidff = kzalloc(sizeof(*pidff), GFP_KERNEL);
1250 	if (!pidff)
1251 		return -ENOMEM;
1252 
1253 	pidff->hid = hid;
1254 
1255 	pidff_find_reports(hid, HID_OUTPUT_REPORT, pidff);
1256 	pidff_find_reports(hid, HID_FEATURE_REPORT, pidff);
1257 
1258 	if (!pidff_reports_ok(pidff)) {
1259 		hid_dbg(hid, "reports not ok, aborting\n");
1260 		error = -ENODEV;
1261 		goto fail;
1262 	}
1263 
1264 	error = pidff_init_fields(pidff, dev);
1265 	if (error)
1266 		goto fail;
1267 
1268 	pidff_reset(pidff);
1269 
1270 	if (test_bit(FF_GAIN, dev->ffbit)) {
1271 		pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], 0xffff);
1272 		usbhid_submit_report(hid, pidff->reports[PID_DEVICE_GAIN],
1273 				     USB_DIR_OUT);
1274 	}
1275 
1276 	error = pidff_check_autocenter(pidff, dev);
1277 	if (error)
1278 		goto fail;
1279 
1280 	max_effects =
1281 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_maximum -
1282 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum +
1283 	    1;
1284 	hid_dbg(hid, "max effects is %d\n", max_effects);
1285 
1286 	if (max_effects > PID_EFFECTS_MAX)
1287 		max_effects = PID_EFFECTS_MAX;
1288 
1289 	if (pidff->pool[PID_SIMULTANEOUS_MAX].value)
1290 		hid_dbg(hid, "max simultaneous effects is %d\n",
1291 			pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);
1292 
1293 	if (pidff->pool[PID_RAM_POOL_SIZE].value)
1294 		hid_dbg(hid, "device memory size is %d bytes\n",
1295 			pidff->pool[PID_RAM_POOL_SIZE].value[0]);
1296 
1297 	if (pidff->pool[PID_DEVICE_MANAGED_POOL].value &&
1298 	    pidff->pool[PID_DEVICE_MANAGED_POOL].value[0] == 0) {
1299 		hid_notice(hid,
1300 			   "device does not support device managed pool\n");
1301 		goto fail;
1302 	}
1303 
1304 	error = input_ff_create(dev, max_effects);
1305 	if (error)
1306 		goto fail;
1307 
1308 	ff = dev->ff;
1309 	ff->private = pidff;
1310 	ff->upload = pidff_upload_effect;
1311 	ff->erase = pidff_erase_effect;
1312 	ff->set_gain = pidff_set_gain;
1313 	ff->set_autocenter = pidff_set_autocenter;
1314 	ff->playback = pidff_playback;
1315 
1316 	hid_info(dev, "Force feedback for USB HID PID devices by Anssi Hannula <anssi.hannula@gmail.com>\n");
1317 
1318 	return 0;
1319 
1320  fail:
1321 	kfree(pidff);
1322 	return error;
1323 }
1324