xref: /openbmc/linux/drivers/hid/usbhid/hid-pidff.c (revision fd589a8f)
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 debug(format, arg...) pr_debug("hid-pidff: " format "\n" , ## arg)
26 
27 #include <linux/input.h>
28 #include <linux/usb.h>
29 
30 #include <linux/hid.h>
31 
32 #include "usbhid.h"
33 
34 #define	PID_EFFECTS_MAX		64
35 
36 /* Report usage table used to put reports into an array */
37 
38 #define PID_SET_EFFECT		0
39 #define PID_EFFECT_OPERATION	1
40 #define PID_DEVICE_GAIN		2
41 #define PID_POOL		3
42 #define PID_BLOCK_LOAD		4
43 #define PID_BLOCK_FREE		5
44 #define PID_DEVICE_CONTROL	6
45 #define PID_CREATE_NEW_EFFECT	7
46 
47 #define PID_REQUIRED_REPORTS	7
48 
49 #define PID_SET_ENVELOPE	8
50 #define PID_SET_CONDITION	9
51 #define PID_SET_PERIODIC	10
52 #define PID_SET_CONSTANT	11
53 #define PID_SET_RAMP		12
54 static const u8 pidff_reports[] = {
55 	0x21, 0x77, 0x7d, 0x7f, 0x89, 0x90, 0x96, 0xab,
56 	0x5a, 0x5f, 0x6e, 0x73, 0x74
57 };
58 
59 /* device_control is really 0x95, but 0x96 specified as it is the usage of
60 the only field in that report */
61 
62 /* Value usage tables used to put fields and values into arrays */
63 
64 #define PID_EFFECT_BLOCK_INDEX	0
65 
66 #define PID_DURATION		1
67 #define PID_GAIN		2
68 #define PID_TRIGGER_BUTTON	3
69 #define PID_TRIGGER_REPEAT_INT	4
70 #define PID_DIRECTION_ENABLE	5
71 #define PID_START_DELAY		6
72 static const u8 pidff_set_effect[] = {
73 	0x22, 0x50, 0x52, 0x53, 0x54, 0x56, 0xa7
74 };
75 
76 #define PID_ATTACK_LEVEL	1
77 #define PID_ATTACK_TIME		2
78 #define PID_FADE_LEVEL		3
79 #define PID_FADE_TIME		4
80 static const u8 pidff_set_envelope[] = { 0x22, 0x5b, 0x5c, 0x5d, 0x5e };
81 
82 #define PID_PARAM_BLOCK_OFFSET	1
83 #define PID_CP_OFFSET		2
84 #define PID_POS_COEFFICIENT	3
85 #define PID_NEG_COEFFICIENT	4
86 #define PID_POS_SATURATION	5
87 #define PID_NEG_SATURATION	6
88 #define PID_DEAD_BAND		7
89 static const u8 pidff_set_condition[] = {
90 	0x22, 0x23, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65
91 };
92 
93 #define PID_MAGNITUDE		1
94 #define PID_OFFSET		2
95 #define PID_PHASE		3
96 #define PID_PERIOD		4
97 static const u8 pidff_set_periodic[] = { 0x22, 0x70, 0x6f, 0x71, 0x72 };
98 static const u8 pidff_set_constant[] = { 0x22, 0x70 };
99 
100 #define PID_RAMP_START		1
101 #define PID_RAMP_END		2
102 static const u8 pidff_set_ramp[] = { 0x22, 0x75, 0x76 };
103 
104 #define PID_RAM_POOL_AVAILABLE	1
105 static const u8 pidff_block_load[] = { 0x22, 0xac };
106 
107 #define PID_LOOP_COUNT		1
108 static const u8 pidff_effect_operation[] = { 0x22, 0x7c };
109 
110 static const u8 pidff_block_free[] = { 0x22 };
111 
112 #define PID_DEVICE_GAIN_FIELD	0
113 static const u8 pidff_device_gain[] = { 0x7e };
114 
115 #define PID_RAM_POOL_SIZE	0
116 #define PID_SIMULTANEOUS_MAX	1
117 #define PID_DEVICE_MANAGED_POOL	2
118 static const u8 pidff_pool[] = { 0x80, 0x83, 0xa9 };
119 
120 /* Special field key tables used to put special field keys into arrays */
121 
122 #define PID_ENABLE_ACTUATORS	0
123 #define PID_RESET		1
124 static const u8 pidff_device_control[] = { 0x97, 0x9a };
125 
126 #define PID_CONSTANT	0
127 #define PID_RAMP	1
128 #define PID_SQUARE	2
129 #define PID_SINE	3
130 #define PID_TRIANGLE	4
131 #define PID_SAW_UP	5
132 #define PID_SAW_DOWN	6
133 #define PID_SPRING	7
134 #define PID_DAMPER	8
135 #define PID_INERTIA	9
136 #define PID_FRICTION	10
137 static const u8 pidff_effect_types[] = {
138 	0x26, 0x27, 0x30, 0x31, 0x32, 0x33, 0x34,
139 	0x40, 0x41, 0x42, 0x43
140 };
141 
142 #define PID_BLOCK_LOAD_SUCCESS	0
143 #define PID_BLOCK_LOAD_FULL	1
144 static const u8 pidff_block_load_status[] = { 0x8c, 0x8d };
145 
146 #define PID_EFFECT_START	0
147 #define PID_EFFECT_STOP		1
148 static const u8 pidff_effect_operation_status[] = { 0x79, 0x7b };
149 
150 struct pidff_usage {
151 	struct hid_field *field;
152 	s32 *value;
153 };
154 
155 struct pidff_device {
156 	struct hid_device *hid;
157 
158 	struct hid_report *reports[sizeof(pidff_reports)];
159 
160 	struct pidff_usage set_effect[sizeof(pidff_set_effect)];
161 	struct pidff_usage set_envelope[sizeof(pidff_set_envelope)];
162 	struct pidff_usage set_condition[sizeof(pidff_set_condition)];
163 	struct pidff_usage set_periodic[sizeof(pidff_set_periodic)];
164 	struct pidff_usage set_constant[sizeof(pidff_set_constant)];
165 	struct pidff_usage set_ramp[sizeof(pidff_set_ramp)];
166 
167 	struct pidff_usage device_gain[sizeof(pidff_device_gain)];
168 	struct pidff_usage block_load[sizeof(pidff_block_load)];
169 	struct pidff_usage pool[sizeof(pidff_pool)];
170 	struct pidff_usage effect_operation[sizeof(pidff_effect_operation)];
171 	struct pidff_usage block_free[sizeof(pidff_block_free)];
172 
173 	/* Special field is a field that is not composed of
174 	   usage<->value pairs that pidff_usage values are */
175 
176 	/* Special field in create_new_effect */
177 	struct hid_field *create_new_effect_type;
178 
179 	/* Special fields in set_effect */
180 	struct hid_field *set_effect_type;
181 	struct hid_field *effect_direction;
182 
183 	/* Special field in device_control */
184 	struct hid_field *device_control;
185 
186 	/* Special field in block_load */
187 	struct hid_field *block_load_status;
188 
189 	/* Special field in effect_operation */
190 	struct hid_field *effect_operation_status;
191 
192 	int control_id[sizeof(pidff_device_control)];
193 	int type_id[sizeof(pidff_effect_types)];
194 	int status_id[sizeof(pidff_block_load_status)];
195 	int operation_id[sizeof(pidff_effect_operation_status)];
196 
197 	int pid_id[PID_EFFECTS_MAX];
198 };
199 
200 /*
201  * Scale an unsigned value with range 0..max for the given field
202  */
203 static int pidff_rescale(int i, int max, struct hid_field *field)
204 {
205 	return i * (field->logical_maximum - field->logical_minimum) / max +
206 	    field->logical_minimum;
207 }
208 
209 /*
210  * Scale a signed value in range -0x8000..0x7fff for the given field
211  */
212 static int pidff_rescale_signed(int i, struct hid_field *field)
213 {
214 	return i == 0 ? 0 : i >
215 	    0 ? i * field->logical_maximum / 0x7fff : i *
216 	    field->logical_minimum / -0x8000;
217 }
218 
219 static void pidff_set(struct pidff_usage *usage, u16 value)
220 {
221 	usage->value[0] = pidff_rescale(value, 0xffff, usage->field);
222 	debug("calculated from %d to %d", value, usage->value[0]);
223 }
224 
225 static void pidff_set_signed(struct pidff_usage *usage, s16 value)
226 {
227 	if (usage->field->logical_minimum < 0)
228 		usage->value[0] = pidff_rescale_signed(value, usage->field);
229 	else {
230 		if (value < 0)
231 			usage->value[0] =
232 			    pidff_rescale(-value, 0x8000, usage->field);
233 		else
234 			usage->value[0] =
235 			    pidff_rescale(value, 0x7fff, usage->field);
236 	}
237 	debug("calculated from %d to %d", value, usage->value[0]);
238 }
239 
240 /*
241  * Send envelope report to the device
242  */
243 static void pidff_set_envelope_report(struct pidff_device *pidff,
244 				      struct ff_envelope *envelope)
245 {
246 	pidff->set_envelope[PID_EFFECT_BLOCK_INDEX].value[0] =
247 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
248 
249 	pidff->set_envelope[PID_ATTACK_LEVEL].value[0] =
250 	    pidff_rescale(envelope->attack_level >
251 			  0x7fff ? 0x7fff : envelope->attack_level, 0x7fff,
252 			  pidff->set_envelope[PID_ATTACK_LEVEL].field);
253 	pidff->set_envelope[PID_FADE_LEVEL].value[0] =
254 	    pidff_rescale(envelope->fade_level >
255 			  0x7fff ? 0x7fff : envelope->fade_level, 0x7fff,
256 			  pidff->set_envelope[PID_FADE_LEVEL].field);
257 
258 	pidff->set_envelope[PID_ATTACK_TIME].value[0] = envelope->attack_length;
259 	pidff->set_envelope[PID_FADE_TIME].value[0] = envelope->fade_length;
260 
261 	debug("attack %u => %d", envelope->attack_level,
262 	      pidff->set_envelope[PID_ATTACK_LEVEL].value[0]);
263 
264 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_ENVELOPE],
265 			  USB_DIR_OUT);
266 }
267 
268 /*
269  * Test if the new envelope differs from old one
270  */
271 static int pidff_needs_set_envelope(struct ff_envelope *envelope,
272 				    struct ff_envelope *old)
273 {
274 	return envelope->attack_level != old->attack_level ||
275 	       envelope->fade_level != old->fade_level ||
276 	       envelope->attack_length != old->attack_length ||
277 	       envelope->fade_length != old->fade_length;
278 }
279 
280 /*
281  * Send constant force report to the device
282  */
283 static void pidff_set_constant_force_report(struct pidff_device *pidff,
284 					    struct ff_effect *effect)
285 {
286 	pidff->set_constant[PID_EFFECT_BLOCK_INDEX].value[0] =
287 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
288 	pidff_set_signed(&pidff->set_constant[PID_MAGNITUDE],
289 			 effect->u.constant.level);
290 
291 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_CONSTANT],
292 			  USB_DIR_OUT);
293 }
294 
295 /*
296  * Test if the constant parameters have changed between effects
297  */
298 static int pidff_needs_set_constant(struct ff_effect *effect,
299 				    struct ff_effect *old)
300 {
301 	return effect->u.constant.level != old->u.constant.level;
302 }
303 
304 /*
305  * Send set effect report to the device
306  */
307 static void pidff_set_effect_report(struct pidff_device *pidff,
308 				    struct ff_effect *effect)
309 {
310 	pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
311 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
312 	pidff->set_effect_type->value[0] =
313 		pidff->create_new_effect_type->value[0];
314 	pidff->set_effect[PID_DURATION].value[0] = effect->replay.length;
315 	pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = effect->trigger.button;
316 	pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] =
317 		effect->trigger.interval;
318 	pidff->set_effect[PID_GAIN].value[0] =
319 		pidff->set_effect[PID_GAIN].field->logical_maximum;
320 	pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
321 	pidff->effect_direction->value[0] =
322 		pidff_rescale(effect->direction, 0xffff,
323 				pidff->effect_direction);
324 	pidff->set_effect[PID_START_DELAY].value[0] = effect->replay.delay;
325 
326 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
327 			  USB_DIR_OUT);
328 }
329 
330 /*
331  * Test if the values used in set_effect have changed
332  */
333 static int pidff_needs_set_effect(struct ff_effect *effect,
334 				  struct ff_effect *old)
335 {
336 	return effect->replay.length != old->replay.length ||
337 	       effect->trigger.interval != old->trigger.interval ||
338 	       effect->trigger.button != old->trigger.button ||
339 	       effect->direction != old->direction ||
340 	       effect->replay.delay != old->replay.delay;
341 }
342 
343 /*
344  * Send periodic effect report to the device
345  */
346 static void pidff_set_periodic_report(struct pidff_device *pidff,
347 				      struct ff_effect *effect)
348 {
349 	pidff->set_periodic[PID_EFFECT_BLOCK_INDEX].value[0] =
350 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
351 	pidff_set_signed(&pidff->set_periodic[PID_MAGNITUDE],
352 			 effect->u.periodic.magnitude);
353 	pidff_set_signed(&pidff->set_periodic[PID_OFFSET],
354 			 effect->u.periodic.offset);
355 	pidff_set(&pidff->set_periodic[PID_PHASE], effect->u.periodic.phase);
356 	pidff->set_periodic[PID_PERIOD].value[0] = effect->u.periodic.period;
357 
358 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_PERIODIC],
359 			  USB_DIR_OUT);
360 
361 }
362 
363 /*
364  * Test if periodic effect parameters have changed
365  */
366 static int pidff_needs_set_periodic(struct ff_effect *effect,
367 				    struct ff_effect *old)
368 {
369 	return effect->u.periodic.magnitude != old->u.periodic.magnitude ||
370 	       effect->u.periodic.offset != old->u.periodic.offset ||
371 	       effect->u.periodic.phase != old->u.periodic.phase ||
372 	       effect->u.periodic.period != old->u.periodic.period;
373 }
374 
375 /*
376  * Send condition effect reports to the device
377  */
378 static void pidff_set_condition_report(struct pidff_device *pidff,
379 				       struct ff_effect *effect)
380 {
381 	int i;
382 
383 	pidff->set_condition[PID_EFFECT_BLOCK_INDEX].value[0] =
384 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
385 
386 	for (i = 0; i < 2; i++) {
387 		pidff->set_condition[PID_PARAM_BLOCK_OFFSET].value[0] = i;
388 		pidff_set_signed(&pidff->set_condition[PID_CP_OFFSET],
389 				 effect->u.condition[i].center);
390 		pidff_set_signed(&pidff->set_condition[PID_POS_COEFFICIENT],
391 				 effect->u.condition[i].right_coeff);
392 		pidff_set_signed(&pidff->set_condition[PID_NEG_COEFFICIENT],
393 				 effect->u.condition[i].left_coeff);
394 		pidff_set(&pidff->set_condition[PID_POS_SATURATION],
395 			  effect->u.condition[i].right_saturation);
396 		pidff_set(&pidff->set_condition[PID_NEG_SATURATION],
397 			  effect->u.condition[i].left_saturation);
398 		pidff_set(&pidff->set_condition[PID_DEAD_BAND],
399 			  effect->u.condition[i].deadband);
400 		usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_CONDITION],
401 				  USB_DIR_OUT);
402 	}
403 }
404 
405 /*
406  * Test if condition effect parameters have changed
407  */
408 static int pidff_needs_set_condition(struct ff_effect *effect,
409 				     struct ff_effect *old)
410 {
411 	int i;
412 	int ret = 0;
413 
414 	for (i = 0; i < 2; i++) {
415 		struct ff_condition_effect *cond = &effect->u.condition[i];
416 		struct ff_condition_effect *old_cond = &old->u.condition[i];
417 
418 		ret |= cond->center != old_cond->center ||
419 		       cond->right_coeff != old_cond->right_coeff ||
420 		       cond->left_coeff != old_cond->left_coeff ||
421 		       cond->right_saturation != old_cond->right_saturation ||
422 		       cond->left_saturation != old_cond->left_saturation ||
423 		       cond->deadband != old_cond->deadband;
424 	}
425 
426 	return ret;
427 }
428 
429 /*
430  * Send ramp force report to the device
431  */
432 static void pidff_set_ramp_force_report(struct pidff_device *pidff,
433 					struct ff_effect *effect)
434 {
435 	pidff->set_ramp[PID_EFFECT_BLOCK_INDEX].value[0] =
436 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
437 	pidff_set_signed(&pidff->set_ramp[PID_RAMP_START],
438 			 effect->u.ramp.start_level);
439 	pidff_set_signed(&pidff->set_ramp[PID_RAMP_END],
440 			 effect->u.ramp.end_level);
441 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_RAMP],
442 			  USB_DIR_OUT);
443 }
444 
445 /*
446  * Test if ramp force parameters have changed
447  */
448 static int pidff_needs_set_ramp(struct ff_effect *effect, struct ff_effect *old)
449 {
450 	return effect->u.ramp.start_level != old->u.ramp.start_level ||
451 	       effect->u.ramp.end_level != old->u.ramp.end_level;
452 }
453 
454 /*
455  * Send a request for effect upload to the device
456  *
457  * Returns 0 if device reported success, -ENOSPC if the device reported memory
458  * is full. Upon unknown response the function will retry for 60 times, if
459  * still unsuccessful -EIO is returned.
460  */
461 static int pidff_request_effect_upload(struct pidff_device *pidff, int efnum)
462 {
463 	int j;
464 
465 	pidff->create_new_effect_type->value[0] = efnum;
466 	usbhid_submit_report(pidff->hid, pidff->reports[PID_CREATE_NEW_EFFECT],
467 			  USB_DIR_OUT);
468 	debug("create_new_effect sent, type: %d", efnum);
469 
470 	pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] = 0;
471 	pidff->block_load_status->value[0] = 0;
472 	usbhid_wait_io(pidff->hid);
473 
474 	for (j = 0; j < 60; j++) {
475 		debug("pid_block_load requested");
476 		usbhid_submit_report(pidff->hid, pidff->reports[PID_BLOCK_LOAD],
477 				  USB_DIR_IN);
478 		usbhid_wait_io(pidff->hid);
479 		if (pidff->block_load_status->value[0] ==
480 		    pidff->status_id[PID_BLOCK_LOAD_SUCCESS]) {
481 			debug("device reported free memory: %d bytes",
482 			      pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
483 				pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
484 			return 0;
485 		}
486 		if (pidff->block_load_status->value[0] ==
487 		    pidff->status_id[PID_BLOCK_LOAD_FULL]) {
488 			debug("not enough memory free: %d bytes",
489 			      pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
490 				pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
491 			return -ENOSPC;
492 		}
493 	}
494 	printk(KERN_ERR "hid-pidff: pid_block_load failed 60 times\n");
495 	return -EIO;
496 }
497 
498 /*
499  * Play the effect with PID id n times
500  */
501 static void pidff_playback_pid(struct pidff_device *pidff, int pid_id, int n)
502 {
503 	pidff->effect_operation[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
504 
505 	if (n == 0) {
506 		pidff->effect_operation_status->value[0] =
507 			pidff->operation_id[PID_EFFECT_STOP];
508 	} else {
509 		pidff->effect_operation_status->value[0] =
510 			pidff->operation_id[PID_EFFECT_START];
511 		pidff->effect_operation[PID_LOOP_COUNT].value[0] = n;
512 	}
513 
514 	usbhid_submit_report(pidff->hid, pidff->reports[PID_EFFECT_OPERATION],
515 			  USB_DIR_OUT);
516 }
517 
518 /**
519  * Play the effect with effect id @effect_id for @value times
520  */
521 static int pidff_playback(struct input_dev *dev, int effect_id, int value)
522 {
523 	struct pidff_device *pidff = dev->ff->private;
524 
525 	pidff_playback_pid(pidff, pidff->pid_id[effect_id], value);
526 
527 	return 0;
528 }
529 
530 /*
531  * Erase effect with PID id
532  */
533 static void pidff_erase_pid(struct pidff_device *pidff, int pid_id)
534 {
535 	pidff->block_free[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
536 	usbhid_submit_report(pidff->hid, pidff->reports[PID_BLOCK_FREE],
537 			  USB_DIR_OUT);
538 }
539 
540 /*
541  * Stop and erase effect with effect_id
542  */
543 static int pidff_erase_effect(struct input_dev *dev, int effect_id)
544 {
545 	struct pidff_device *pidff = dev->ff->private;
546 	int pid_id = pidff->pid_id[effect_id];
547 
548 	debug("starting to erase %d/%d", effect_id, pidff->pid_id[effect_id]);
549 	/* Wait for the queue to clear. We do not want a full fifo to
550 	   prevent the effect removal. */
551 	usbhid_wait_io(pidff->hid);
552 	pidff_playback_pid(pidff, pid_id, 0);
553 	pidff_erase_pid(pidff, pid_id);
554 
555 	return 0;
556 }
557 
558 /*
559  * Effect upload handler
560  */
561 static int pidff_upload_effect(struct input_dev *dev, struct ff_effect *effect,
562 			       struct ff_effect *old)
563 {
564 	struct pidff_device *pidff = dev->ff->private;
565 	int type_id;
566 	int error;
567 
568 	switch (effect->type) {
569 	case FF_CONSTANT:
570 		if (!old) {
571 			error = pidff_request_effect_upload(pidff,
572 					pidff->type_id[PID_CONSTANT]);
573 			if (error)
574 				return error;
575 		}
576 		if (!old || pidff_needs_set_effect(effect, old))
577 			pidff_set_effect_report(pidff, effect);
578 		if (!old || pidff_needs_set_constant(effect, old))
579 			pidff_set_constant_force_report(pidff, effect);
580 		if (!old ||
581 		    pidff_needs_set_envelope(&effect->u.constant.envelope,
582 					&old->u.constant.envelope))
583 			pidff_set_envelope_report(pidff,
584 					&effect->u.constant.envelope);
585 		break;
586 
587 	case FF_PERIODIC:
588 		if (!old) {
589 			switch (effect->u.periodic.waveform) {
590 			case FF_SQUARE:
591 				type_id = PID_SQUARE;
592 				break;
593 			case FF_TRIANGLE:
594 				type_id = PID_TRIANGLE;
595 				break;
596 			case FF_SINE:
597 				type_id = PID_SINE;
598 				break;
599 			case FF_SAW_UP:
600 				type_id = PID_SAW_UP;
601 				break;
602 			case FF_SAW_DOWN:
603 				type_id = PID_SAW_DOWN;
604 				break;
605 			default:
606 				printk(KERN_ERR
607 				       "hid-pidff: invalid waveform\n");
608 				return -EINVAL;
609 			}
610 
611 			error = pidff_request_effect_upload(pidff,
612 					pidff->type_id[type_id]);
613 			if (error)
614 				return error;
615 		}
616 		if (!old || pidff_needs_set_effect(effect, old))
617 			pidff_set_effect_report(pidff, effect);
618 		if (!old || pidff_needs_set_periodic(effect, old))
619 			pidff_set_periodic_report(pidff, effect);
620 		if (!old ||
621 		    pidff_needs_set_envelope(&effect->u.periodic.envelope,
622 					&old->u.periodic.envelope))
623 			pidff_set_envelope_report(pidff,
624 					&effect->u.periodic.envelope);
625 		break;
626 
627 	case FF_RAMP:
628 		if (!old) {
629 			error = pidff_request_effect_upload(pidff,
630 					pidff->type_id[PID_RAMP]);
631 			if (error)
632 				return error;
633 		}
634 		if (!old || pidff_needs_set_effect(effect, old))
635 			pidff_set_effect_report(pidff, effect);
636 		if (!old || pidff_needs_set_ramp(effect, old))
637 			pidff_set_ramp_force_report(pidff, effect);
638 		if (!old ||
639 		    pidff_needs_set_envelope(&effect->u.ramp.envelope,
640 					&old->u.ramp.envelope))
641 			pidff_set_envelope_report(pidff,
642 					&effect->u.ramp.envelope);
643 		break;
644 
645 	case FF_SPRING:
646 		if (!old) {
647 			error = pidff_request_effect_upload(pidff,
648 					pidff->type_id[PID_SPRING]);
649 			if (error)
650 				return error;
651 		}
652 		if (!old || pidff_needs_set_effect(effect, old))
653 			pidff_set_effect_report(pidff, effect);
654 		if (!old || pidff_needs_set_condition(effect, old))
655 			pidff_set_condition_report(pidff, effect);
656 		break;
657 
658 	case FF_FRICTION:
659 		if (!old) {
660 			error = pidff_request_effect_upload(pidff,
661 					pidff->type_id[PID_FRICTION]);
662 			if (error)
663 				return error;
664 		}
665 		if (!old || pidff_needs_set_effect(effect, old))
666 			pidff_set_effect_report(pidff, effect);
667 		if (!old || pidff_needs_set_condition(effect, old))
668 			pidff_set_condition_report(pidff, effect);
669 		break;
670 
671 	case FF_DAMPER:
672 		if (!old) {
673 			error = pidff_request_effect_upload(pidff,
674 					pidff->type_id[PID_DAMPER]);
675 			if (error)
676 				return error;
677 		}
678 		if (!old || pidff_needs_set_effect(effect, old))
679 			pidff_set_effect_report(pidff, effect);
680 		if (!old || pidff_needs_set_condition(effect, old))
681 			pidff_set_condition_report(pidff, effect);
682 		break;
683 
684 	case FF_INERTIA:
685 		if (!old) {
686 			error = pidff_request_effect_upload(pidff,
687 					pidff->type_id[PID_INERTIA]);
688 			if (error)
689 				return error;
690 		}
691 		if (!old || pidff_needs_set_effect(effect, old))
692 			pidff_set_effect_report(pidff, effect);
693 		if (!old || pidff_needs_set_condition(effect, old))
694 			pidff_set_condition_report(pidff, effect);
695 		break;
696 
697 	default:
698 		printk(KERN_ERR "hid-pidff: invalid type\n");
699 		return -EINVAL;
700 	}
701 
702 	if (!old)
703 		pidff->pid_id[effect->id] =
704 		    pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
705 
706 	debug("uploaded");
707 
708 	return 0;
709 }
710 
711 /*
712  * set_gain() handler
713  */
714 static void pidff_set_gain(struct input_dev *dev, u16 gain)
715 {
716 	struct pidff_device *pidff = dev->ff->private;
717 
718 	pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], gain);
719 	usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
720 			  USB_DIR_OUT);
721 }
722 
723 static void pidff_autocenter(struct pidff_device *pidff, u16 magnitude)
724 {
725 	struct hid_field *field =
726 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].field;
727 
728 	if (!magnitude) {
729 		pidff_playback_pid(pidff, field->logical_minimum, 0);
730 		return;
731 	}
732 
733 	pidff_playback_pid(pidff, field->logical_minimum, 1);
734 
735 	pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
736 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum;
737 	pidff->set_effect_type->value[0] = pidff->type_id[PID_SPRING];
738 	pidff->set_effect[PID_DURATION].value[0] = 0;
739 	pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = 0;
740 	pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] = 0;
741 	pidff_set(&pidff->set_effect[PID_GAIN], magnitude);
742 	pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
743 	pidff->set_effect[PID_START_DELAY].value[0] = 0;
744 
745 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
746 			  USB_DIR_OUT);
747 }
748 
749 /*
750  * pidff_set_autocenter() handler
751  */
752 static void pidff_set_autocenter(struct input_dev *dev, u16 magnitude)
753 {
754 	struct pidff_device *pidff = dev->ff->private;
755 
756 	pidff_autocenter(pidff, magnitude);
757 }
758 
759 /*
760  * Find fields from a report and fill a pidff_usage
761  */
762 static int pidff_find_fields(struct pidff_usage *usage, const u8 *table,
763 			     struct hid_report *report, int count, int strict)
764 {
765 	int i, j, k, found;
766 
767 	for (k = 0; k < count; k++) {
768 		found = 0;
769 		for (i = 0; i < report->maxfield; i++) {
770 			if (report->field[i]->maxusage !=
771 			    report->field[i]->report_count) {
772 				debug("maxusage and report_count do not match, "
773 				      "skipping");
774 				continue;
775 			}
776 			for (j = 0; j < report->field[i]->maxusage; j++) {
777 				if (report->field[i]->usage[j].hid ==
778 				    (HID_UP_PID | table[k])) {
779 					debug("found %d at %d->%d", k, i, j);
780 					usage[k].field = report->field[i];
781 					usage[k].value =
782 						&report->field[i]->value[j];
783 					found = 1;
784 					break;
785 				}
786 			}
787 			if (found)
788 				break;
789 		}
790 		if (!found && strict) {
791 			debug("failed to locate %d", k);
792 			return -1;
793 		}
794 	}
795 	return 0;
796 }
797 
798 /*
799  * Return index into pidff_reports for the given usage
800  */
801 static int pidff_check_usage(int usage)
802 {
803 	int i;
804 
805 	for (i = 0; i < sizeof(pidff_reports); i++)
806 		if (usage == (HID_UP_PID | pidff_reports[i]))
807 			return i;
808 
809 	return -1;
810 }
811 
812 /*
813  * Find the reports and fill pidff->reports[]
814  * report_type specifies either OUTPUT or FEATURE reports
815  */
816 static void pidff_find_reports(struct hid_device *hid, int report_type,
817 			       struct pidff_device *pidff)
818 {
819 	struct hid_report *report;
820 	int i, ret;
821 
822 	list_for_each_entry(report,
823 			    &hid->report_enum[report_type].report_list, list) {
824 		if (report->maxfield < 1)
825 			continue;
826 		ret = pidff_check_usage(report->field[0]->logical);
827 		if (ret != -1) {
828 			debug("found usage 0x%02x from field->logical",
829 			      pidff_reports[ret]);
830 			pidff->reports[ret] = report;
831 			continue;
832 		}
833 
834 		/*
835 		 * Sometimes logical collections are stacked to indicate
836 		 * different usages for the report and the field, in which
837 		 * case we want the usage of the parent. However, Linux HID
838 		 * implementation hides this fact, so we have to dig it up
839 		 * ourselves
840 		 */
841 		i = report->field[0]->usage[0].collection_index;
842 		if (i <= 0 ||
843 		    hid->collection[i - 1].type != HID_COLLECTION_LOGICAL)
844 			continue;
845 		ret = pidff_check_usage(hid->collection[i - 1].usage);
846 		if (ret != -1 && !pidff->reports[ret]) {
847 			debug("found usage 0x%02x from collection array",
848 			      pidff_reports[ret]);
849 			pidff->reports[ret] = report;
850 		}
851 	}
852 }
853 
854 /*
855  * Test if the required reports have been found
856  */
857 static int pidff_reports_ok(struct pidff_device *pidff)
858 {
859 	int i;
860 
861 	for (i = 0; i <= PID_REQUIRED_REPORTS; i++) {
862 		if (!pidff->reports[i]) {
863 			debug("%d missing", i);
864 			return 0;
865 		}
866 	}
867 
868 	return 1;
869 }
870 
871 /*
872  * Find a field with a specific usage within a report
873  */
874 static struct hid_field *pidff_find_special_field(struct hid_report *report,
875 						  int usage, int enforce_min)
876 {
877 	int i;
878 
879 	for (i = 0; i < report->maxfield; i++) {
880 		if (report->field[i]->logical == (HID_UP_PID | usage) &&
881 		    report->field[i]->report_count > 0) {
882 			if (!enforce_min ||
883 			    report->field[i]->logical_minimum == 1)
884 				return report->field[i];
885 			else {
886 				printk(KERN_ERR "hid-pidff: logical_minimum "
887 					"is not 1 as it should be\n");
888 				return NULL;
889 			}
890 		}
891 	}
892 	return NULL;
893 }
894 
895 /*
896  * Fill a pidff->*_id struct table
897  */
898 static int pidff_find_special_keys(int *keys, struct hid_field *fld,
899 				   const u8 *usagetable, int count)
900 {
901 
902 	int i, j;
903 	int found = 0;
904 
905 	for (i = 0; i < count; i++) {
906 		for (j = 0; j < fld->maxusage; j++) {
907 			if (fld->usage[j].hid == (HID_UP_PID | usagetable[i])) {
908 				keys[i] = j + 1;
909 				found++;
910 				break;
911 			}
912 		}
913 	}
914 	return found;
915 }
916 
917 #define PIDFF_FIND_SPECIAL_KEYS(keys, field, name) \
918 	pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
919 		sizeof(pidff_ ## name))
920 
921 /*
922  * Find and check the special fields
923  */
924 static int pidff_find_special_fields(struct pidff_device *pidff)
925 {
926 	debug("finding special fields");
927 
928 	pidff->create_new_effect_type =
929 		pidff_find_special_field(pidff->reports[PID_CREATE_NEW_EFFECT],
930 					 0x25, 1);
931 	pidff->set_effect_type =
932 		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
933 					 0x25, 1);
934 	pidff->effect_direction =
935 		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
936 					 0x57, 0);
937 	pidff->device_control =
938 		pidff_find_special_field(pidff->reports[PID_DEVICE_CONTROL],
939 					 0x96, 1);
940 	pidff->block_load_status =
941 		pidff_find_special_field(pidff->reports[PID_BLOCK_LOAD],
942 					 0x8b, 1);
943 	pidff->effect_operation_status =
944 		pidff_find_special_field(pidff->reports[PID_EFFECT_OPERATION],
945 					 0x78, 1);
946 
947 	debug("search done");
948 
949 	if (!pidff->create_new_effect_type || !pidff->set_effect_type) {
950 		printk(KERN_ERR "hid-pidff: effect lists not found\n");
951 		return -1;
952 	}
953 
954 	if (!pidff->effect_direction) {
955 		printk(KERN_ERR "hid-pidff: direction field not found\n");
956 		return -1;
957 	}
958 
959 	if (!pidff->device_control) {
960 		printk(KERN_ERR "hid-pidff: device control field not found\n");
961 		return -1;
962 	}
963 
964 	if (!pidff->block_load_status) {
965 		printk(KERN_ERR
966 		       "hid-pidff: block load status field not found\n");
967 		return -1;
968 	}
969 
970 	if (!pidff->effect_operation_status) {
971 		printk(KERN_ERR
972 		       "hid-pidff: 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 		printk(KERN_ERR "hid-pidff: 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 		printk(KERN_ERR
992 		       "hidpidff: 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 		printk(KERN_ERR
1000 		       "hidpidff: effect operation identifiers not found\n");
1001 		return -1;
1002 	}
1003 
1004 	return 0;
1005 }
1006 
1007 /**
1008  * Find the implemented effect types
1009  */
1010 static int pidff_find_effects(struct pidff_device *pidff,
1011 			      struct input_dev *dev)
1012 {
1013 	int i;
1014 
1015 	for (i = 0; i < sizeof(pidff_effect_types); i++) {
1016 		int pidff_type = pidff->type_id[i];
1017 		if (pidff->set_effect_type->usage[pidff_type].hid !=
1018 		    pidff->create_new_effect_type->usage[pidff_type].hid) {
1019 			printk(KERN_ERR "hid-pidff: "
1020 			       "effect type number %d is invalid\n", i);
1021 			return -1;
1022 		}
1023 	}
1024 
1025 	if (pidff->type_id[PID_CONSTANT])
1026 		set_bit(FF_CONSTANT, dev->ffbit);
1027 	if (pidff->type_id[PID_RAMP])
1028 		set_bit(FF_RAMP, dev->ffbit);
1029 	if (pidff->type_id[PID_SQUARE]) {
1030 		set_bit(FF_SQUARE, dev->ffbit);
1031 		set_bit(FF_PERIODIC, dev->ffbit);
1032 	}
1033 	if (pidff->type_id[PID_SINE]) {
1034 		set_bit(FF_SINE, dev->ffbit);
1035 		set_bit(FF_PERIODIC, dev->ffbit);
1036 	}
1037 	if (pidff->type_id[PID_TRIANGLE]) {
1038 		set_bit(FF_TRIANGLE, dev->ffbit);
1039 		set_bit(FF_PERIODIC, dev->ffbit);
1040 	}
1041 	if (pidff->type_id[PID_SAW_UP]) {
1042 		set_bit(FF_SAW_UP, dev->ffbit);
1043 		set_bit(FF_PERIODIC, dev->ffbit);
1044 	}
1045 	if (pidff->type_id[PID_SAW_DOWN]) {
1046 		set_bit(FF_SAW_DOWN, dev->ffbit);
1047 		set_bit(FF_PERIODIC, dev->ffbit);
1048 	}
1049 	if (pidff->type_id[PID_SPRING])
1050 		set_bit(FF_SPRING, dev->ffbit);
1051 	if (pidff->type_id[PID_DAMPER])
1052 		set_bit(FF_DAMPER, dev->ffbit);
1053 	if (pidff->type_id[PID_INERTIA])
1054 		set_bit(FF_INERTIA, dev->ffbit);
1055 	if (pidff->type_id[PID_FRICTION])
1056 		set_bit(FF_FRICTION, dev->ffbit);
1057 
1058 	return 0;
1059 
1060 }
1061 
1062 #define PIDFF_FIND_FIELDS(name, report, strict) \
1063 	pidff_find_fields(pidff->name, pidff_ ## name, \
1064 		pidff->reports[report], \
1065 		sizeof(pidff_ ## name), strict)
1066 
1067 /*
1068  * Fill and check the pidff_usages
1069  */
1070 static int pidff_init_fields(struct pidff_device *pidff, struct input_dev *dev)
1071 {
1072 	int envelope_ok = 0;
1073 
1074 	if (PIDFF_FIND_FIELDS(set_effect, PID_SET_EFFECT, 1)) {
1075 		printk(KERN_ERR
1076 		       "hid-pidff: unknown set_effect report layout\n");
1077 		return -ENODEV;
1078 	}
1079 
1080 	PIDFF_FIND_FIELDS(block_load, PID_BLOCK_LOAD, 0);
1081 	if (!pidff->block_load[PID_EFFECT_BLOCK_INDEX].value) {
1082 		printk(KERN_ERR
1083 		       "hid-pidff: unknown pid_block_load report layout\n");
1084 		return -ENODEV;
1085 	}
1086 
1087 	if (PIDFF_FIND_FIELDS(effect_operation, PID_EFFECT_OPERATION, 1)) {
1088 		printk(KERN_ERR
1089 		       "hid-pidff: unknown effect_operation report layout\n");
1090 		return -ENODEV;
1091 	}
1092 
1093 	if (PIDFF_FIND_FIELDS(block_free, PID_BLOCK_FREE, 1)) {
1094 		printk(KERN_ERR
1095 		       "hid-pidff: unknown pid_block_free report layout\n");
1096 		return -ENODEV;
1097 	}
1098 
1099 	if (!PIDFF_FIND_FIELDS(set_envelope, PID_SET_ENVELOPE, 1))
1100 		envelope_ok = 1;
1101 
1102 	if (pidff_find_special_fields(pidff) || pidff_find_effects(pidff, dev))
1103 		return -ENODEV;
1104 
1105 	if (!envelope_ok) {
1106 		if (test_and_clear_bit(FF_CONSTANT, dev->ffbit))
1107 			printk(KERN_WARNING "hid-pidff: "
1108 			       "has constant effect but no envelope\n");
1109 		if (test_and_clear_bit(FF_RAMP, dev->ffbit))
1110 			printk(KERN_WARNING "hid-pidff: "
1111 				"has ramp effect but no envelope\n");
1112 
1113 		if (test_and_clear_bit(FF_PERIODIC, dev->ffbit))
1114 			printk(KERN_WARNING "hid-pidff: "
1115 				"has periodic effect but no envelope\n");
1116 	}
1117 
1118 	if (test_bit(FF_CONSTANT, dev->ffbit) &&
1119 	    PIDFF_FIND_FIELDS(set_constant, PID_SET_CONSTANT, 1)) {
1120 		printk(KERN_WARNING
1121 		       "hid-pidff: unknown constant effect layout\n");
1122 		clear_bit(FF_CONSTANT, dev->ffbit);
1123 	}
1124 
1125 	if (test_bit(FF_RAMP, dev->ffbit) &&
1126 	    PIDFF_FIND_FIELDS(set_ramp, PID_SET_RAMP, 1)) {
1127 		printk(KERN_WARNING "hid-pidff: unknown ramp effect layout\n");
1128 		clear_bit(FF_RAMP, dev->ffbit);
1129 	}
1130 
1131 	if ((test_bit(FF_SPRING, dev->ffbit) ||
1132 	     test_bit(FF_DAMPER, dev->ffbit) ||
1133 	     test_bit(FF_FRICTION, dev->ffbit) ||
1134 	     test_bit(FF_INERTIA, dev->ffbit)) &&
1135 	    PIDFF_FIND_FIELDS(set_condition, PID_SET_CONDITION, 1)) {
1136 		printk(KERN_WARNING
1137 		       "hid-pidff: unknown condition effect layout\n");
1138 		clear_bit(FF_SPRING, dev->ffbit);
1139 		clear_bit(FF_DAMPER, dev->ffbit);
1140 		clear_bit(FF_FRICTION, dev->ffbit);
1141 		clear_bit(FF_INERTIA, dev->ffbit);
1142 	}
1143 
1144 	if (test_bit(FF_PERIODIC, dev->ffbit) &&
1145 	    PIDFF_FIND_FIELDS(set_periodic, PID_SET_PERIODIC, 1)) {
1146 		printk(KERN_WARNING
1147 		       "hid-pidff: unknown periodic effect layout\n");
1148 		clear_bit(FF_PERIODIC, dev->ffbit);
1149 	}
1150 
1151 	PIDFF_FIND_FIELDS(pool, PID_POOL, 0);
1152 
1153 	if (!PIDFF_FIND_FIELDS(device_gain, PID_DEVICE_GAIN, 1))
1154 		set_bit(FF_GAIN, dev->ffbit);
1155 
1156 	return 0;
1157 }
1158 
1159 /*
1160  * Reset the device
1161  */
1162 static void pidff_reset(struct pidff_device *pidff)
1163 {
1164 	struct hid_device *hid = pidff->hid;
1165 	int i = 0;
1166 
1167 	pidff->device_control->value[0] = pidff->control_id[PID_RESET];
1168 	/* We reset twice as sometimes hid_wait_io isn't waiting long enough */
1169 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1170 	usbhid_wait_io(hid);
1171 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1172 	usbhid_wait_io(hid);
1173 
1174 	pidff->device_control->value[0] =
1175 		pidff->control_id[PID_ENABLE_ACTUATORS];
1176 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1177 	usbhid_wait_io(hid);
1178 
1179 	/* pool report is sometimes messed up, refetch it */
1180 	usbhid_submit_report(hid, pidff->reports[PID_POOL], USB_DIR_IN);
1181 	usbhid_wait_io(hid);
1182 
1183 	if (pidff->pool[PID_SIMULTANEOUS_MAX].value) {
1184 		int sim_effects = pidff->pool[PID_SIMULTANEOUS_MAX].value[0];
1185 		while (sim_effects < 2) {
1186 			if (i++ > 20) {
1187 				printk(KERN_WARNING "hid-pidff: device reports "
1188 				       "%d simultaneous effects\n",
1189 				       sim_effects);
1190 				break;
1191 			}
1192 			debug("pid_pool requested again");
1193 			usbhid_submit_report(hid, pidff->reports[PID_POOL],
1194 					  USB_DIR_IN);
1195 			usbhid_wait_io(hid);
1196 		}
1197 	}
1198 }
1199 
1200 /*
1201  * Test if autocenter modification is using the supported method
1202  */
1203 static int pidff_check_autocenter(struct pidff_device *pidff,
1204 				  struct input_dev *dev)
1205 {
1206 	int error;
1207 
1208 	/*
1209 	 * Let's find out if autocenter modification is supported
1210 	 * Specification doesn't specify anything, so we request an
1211 	 * effect upload and cancel it immediately. If the approved
1212 	 * effect id was one above the minimum, then we assume the first
1213 	 * effect id is a built-in spring type effect used for autocenter
1214 	 */
1215 
1216 	error = pidff_request_effect_upload(pidff, 1);
1217 	if (error) {
1218 		printk(KERN_ERR "hid-pidff: upload request failed\n");
1219 		return error;
1220 	}
1221 
1222 	if (pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] ==
1223 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum + 1) {
1224 		pidff_autocenter(pidff, 0xffff);
1225 		set_bit(FF_AUTOCENTER, dev->ffbit);
1226 	} else {
1227 		printk(KERN_NOTICE "hid-pidff: "
1228 		       "device has unknown autocenter control method\n");
1229 	}
1230 
1231 	pidff_erase_pid(pidff,
1232 			pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0]);
1233 
1234 	return 0;
1235 
1236 }
1237 
1238 /*
1239  * Check if the device is PID and initialize it
1240  */
1241 int hid_pidff_init(struct hid_device *hid)
1242 {
1243 	struct pidff_device *pidff;
1244 	struct hid_input *hidinput = list_entry(hid->inputs.next,
1245 						struct hid_input, list);
1246 	struct input_dev *dev = hidinput->input;
1247 	struct ff_device *ff;
1248 	int max_effects;
1249 	int error;
1250 
1251 	debug("starting pid init");
1252 
1253 	if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {
1254 		debug("not a PID device, no output report");
1255 		return -ENODEV;
1256 	}
1257 
1258 	pidff = kzalloc(sizeof(*pidff), GFP_KERNEL);
1259 	if (!pidff)
1260 		return -ENOMEM;
1261 
1262 	pidff->hid = hid;
1263 
1264 	pidff_find_reports(hid, HID_OUTPUT_REPORT, pidff);
1265 	pidff_find_reports(hid, HID_FEATURE_REPORT, pidff);
1266 
1267 	if (!pidff_reports_ok(pidff)) {
1268 		debug("reports not ok, aborting");
1269 		error = -ENODEV;
1270 		goto fail;
1271 	}
1272 
1273 	error = pidff_init_fields(pidff, dev);
1274 	if (error)
1275 		goto fail;
1276 
1277 	pidff_reset(pidff);
1278 
1279 	if (test_bit(FF_GAIN, dev->ffbit)) {
1280 		pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], 0xffff);
1281 		usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
1282 				  USB_DIR_OUT);
1283 	}
1284 
1285 	error = pidff_check_autocenter(pidff, dev);
1286 	if (error)
1287 		goto fail;
1288 
1289 	max_effects =
1290 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_maximum -
1291 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum +
1292 	    1;
1293 	debug("max effects is %d", max_effects);
1294 
1295 	if (max_effects > PID_EFFECTS_MAX)
1296 		max_effects = PID_EFFECTS_MAX;
1297 
1298 	if (pidff->pool[PID_SIMULTANEOUS_MAX].value)
1299 		debug("max simultaneous effects is %d",
1300 		      pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);
1301 
1302 	if (pidff->pool[PID_RAM_POOL_SIZE].value)
1303 		debug("device memory size is %d bytes",
1304 		      pidff->pool[PID_RAM_POOL_SIZE].value[0]);
1305 
1306 	if (pidff->pool[PID_DEVICE_MANAGED_POOL].value &&
1307 	    pidff->pool[PID_DEVICE_MANAGED_POOL].value[0] == 0) {
1308 		printk(KERN_NOTICE "hid-pidff: "
1309 		       "device does not support device managed pool\n");
1310 		goto fail;
1311 	}
1312 
1313 	error = input_ff_create(dev, max_effects);
1314 	if (error)
1315 		goto fail;
1316 
1317 	ff = dev->ff;
1318 	ff->private = pidff;
1319 	ff->upload = pidff_upload_effect;
1320 	ff->erase = pidff_erase_effect;
1321 	ff->set_gain = pidff_set_gain;
1322 	ff->set_autocenter = pidff_set_autocenter;
1323 	ff->playback = pidff_playback;
1324 
1325 	printk(KERN_INFO "Force feedback for USB HID PID devices by "
1326 	       "Anssi Hannula <anssi.hannula@gmail.com>\n");
1327 
1328 	return 0;
1329 
1330  fail:
1331 	kfree(pidff);
1332 	return error;
1333 }
1334