xref: /openbmc/linux/drivers/hid/usbhid/hid-pidff.c (revision 96de0e252cedffad61b3cb5e05662c591898e69a)
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_wait_io(pidff->hid);
401 		usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_CONDITION],
402 				  USB_DIR_OUT);
403 	}
404 }
405 
406 /*
407  * Test if condition effect parameters have changed
408  */
409 static int pidff_needs_set_condition(struct ff_effect *effect,
410 				     struct ff_effect *old)
411 {
412 	int i;
413 	int ret = 0;
414 
415 	for (i = 0; i < 2; i++) {
416 		struct ff_condition_effect *cond = &effect->u.condition[i];
417 		struct ff_condition_effect *old_cond = &old->u.condition[i];
418 
419 		ret |= cond->center != old_cond->center ||
420 		       cond->right_coeff != old_cond->right_coeff ||
421 		       cond->left_coeff != old_cond->left_coeff ||
422 		       cond->right_saturation != old_cond->right_saturation ||
423 		       cond->left_saturation != old_cond->left_saturation ||
424 		       cond->deadband != old_cond->deadband;
425 	}
426 
427 	return ret;
428 }
429 
430 /*
431  * Send ramp force report to the device
432  */
433 static void pidff_set_ramp_force_report(struct pidff_device *pidff,
434 					struct ff_effect *effect)
435 {
436 	pidff->set_ramp[PID_EFFECT_BLOCK_INDEX].value[0] =
437 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
438 	pidff_set_signed(&pidff->set_ramp[PID_RAMP_START],
439 			 effect->u.ramp.start_level);
440 	pidff_set_signed(&pidff->set_ramp[PID_RAMP_END],
441 			 effect->u.ramp.end_level);
442 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_RAMP],
443 			  USB_DIR_OUT);
444 }
445 
446 /*
447  * Test if ramp force parameters have changed
448  */
449 static int pidff_needs_set_ramp(struct ff_effect *effect, struct ff_effect *old)
450 {
451 	return effect->u.ramp.start_level != old->u.ramp.start_level ||
452 	       effect->u.ramp.end_level != old->u.ramp.end_level;
453 }
454 
455 /*
456  * Send a request for effect upload to the device
457  *
458  * Returns 0 if device reported success, -ENOSPC if the device reported memory
459  * is full. Upon unknown response the function will retry for 60 times, if
460  * still unsuccessful -EIO is returned.
461  */
462 static int pidff_request_effect_upload(struct pidff_device *pidff, int efnum)
463 {
464 	int j;
465 
466 	pidff->create_new_effect_type->value[0] = efnum;
467 	usbhid_submit_report(pidff->hid, pidff->reports[PID_CREATE_NEW_EFFECT],
468 			  USB_DIR_OUT);
469 	debug("create_new_effect sent, type: %d", efnum);
470 
471 	pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] = 0;
472 	pidff->block_load_status->value[0] = 0;
473 	usbhid_wait_io(pidff->hid);
474 
475 	for (j = 0; j < 60; j++) {
476 		debug("pid_block_load requested");
477 		usbhid_submit_report(pidff->hid, pidff->reports[PID_BLOCK_LOAD],
478 				  USB_DIR_IN);
479 		usbhid_wait_io(pidff->hid);
480 		if (pidff->block_load_status->value[0] ==
481 		    pidff->status_id[PID_BLOCK_LOAD_SUCCESS]) {
482 			debug("device reported free memory: %d bytes",
483 			      pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
484 				pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
485 			return 0;
486 		}
487 		if (pidff->block_load_status->value[0] ==
488 		    pidff->status_id[PID_BLOCK_LOAD_FULL]) {
489 			debug("not enough memory free: %d bytes",
490 			      pidff->block_load[PID_RAM_POOL_AVAILABLE].value ?
491 				pidff->block_load[PID_RAM_POOL_AVAILABLE].value[0] : -1);
492 			return -ENOSPC;
493 		}
494 	}
495 	printk(KERN_ERR "hid-pidff: pid_block_load failed 60 times\n");
496 	return -EIO;
497 }
498 
499 /*
500  * Play the effect with PID id n times
501  */
502 static void pidff_playback_pid(struct pidff_device *pidff, int pid_id, int n)
503 {
504 	pidff->effect_operation[PID_EFFECT_BLOCK_INDEX].value[0] = pid_id;
505 
506 	if (n == 0) {
507 		pidff->effect_operation_status->value[0] =
508 			pidff->operation_id[PID_EFFECT_STOP];
509 	} else {
510 		pidff->effect_operation_status->value[0] =
511 			pidff->operation_id[PID_EFFECT_START];
512 		pidff->effect_operation[PID_LOOP_COUNT].value[0] = n;
513 	}
514 
515 	usbhid_wait_io(pidff->hid);
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 	debug("starting to erase %d/%d", effect_id, pidff->pid_id[effect_id]);
551 	pidff_playback_pid(pidff, pid_id, 0);
552 	pidff_erase_pid(pidff, pid_id);
553 
554 	return 0;
555 }
556 
557 /*
558  * Effect upload handler
559  */
560 static int pidff_upload_effect(struct input_dev *dev, struct ff_effect *effect,
561 			       struct ff_effect *old)
562 {
563 	struct pidff_device *pidff = dev->ff->private;
564 	int type_id;
565 	int error;
566 
567 	switch (effect->type) {
568 	case FF_CONSTANT:
569 		if (!old) {
570 			error = pidff_request_effect_upload(pidff,
571 					pidff->type_id[PID_CONSTANT]);
572 			if (error)
573 				return error;
574 		}
575 		if (!old || pidff_needs_set_effect(effect, old))
576 			pidff_set_effect_report(pidff, effect);
577 		if (!old || pidff_needs_set_constant(effect, old))
578 			pidff_set_constant_force_report(pidff, effect);
579 		if (!old ||
580 		    pidff_needs_set_envelope(&effect->u.constant.envelope,
581 					&old->u.constant.envelope))
582 			pidff_set_envelope_report(pidff,
583 					&effect->u.constant.envelope);
584 		break;
585 
586 	case FF_PERIODIC:
587 		if (!old) {
588 			switch (effect->u.periodic.waveform) {
589 			case FF_SQUARE:
590 				type_id = PID_SQUARE;
591 				break;
592 			case FF_TRIANGLE:
593 				type_id = PID_TRIANGLE;
594 				break;
595 			case FF_SINE:
596 				type_id = PID_SINE;
597 				break;
598 			case FF_SAW_UP:
599 				type_id = PID_SAW_UP;
600 				break;
601 			case FF_SAW_DOWN:
602 				type_id = PID_SAW_DOWN;
603 				break;
604 			default:
605 				printk(KERN_ERR
606 				       "hid-pidff: invalid waveform\n");
607 				return -EINVAL;
608 			}
609 
610 			error = pidff_request_effect_upload(pidff,
611 					pidff->type_id[type_id]);
612 			if (error)
613 				return error;
614 		}
615 		if (!old || pidff_needs_set_effect(effect, old))
616 			pidff_set_effect_report(pidff, effect);
617 		if (!old || pidff_needs_set_periodic(effect, old))
618 			pidff_set_periodic_report(pidff, effect);
619 		if (!old ||
620 		    pidff_needs_set_envelope(&effect->u.periodic.envelope,
621 					&old->u.periodic.envelope))
622 			pidff_set_envelope_report(pidff,
623 					&effect->u.periodic.envelope);
624 		break;
625 
626 	case FF_RAMP:
627 		if (!old) {
628 			error = pidff_request_effect_upload(pidff,
629 					pidff->type_id[PID_RAMP]);
630 			if (error)
631 				return error;
632 		}
633 		if (!old || pidff_needs_set_effect(effect, old))
634 			pidff_set_effect_report(pidff, effect);
635 		if (!old || pidff_needs_set_ramp(effect, old))
636 			pidff_set_ramp_force_report(pidff, effect);
637 		if (!old ||
638 		    pidff_needs_set_envelope(&effect->u.ramp.envelope,
639 					&old->u.ramp.envelope))
640 			pidff_set_envelope_report(pidff,
641 					&effect->u.ramp.envelope);
642 		break;
643 
644 	case FF_SPRING:
645 		if (!old) {
646 			error = pidff_request_effect_upload(pidff,
647 					pidff->type_id[PID_SPRING]);
648 			if (error)
649 				return error;
650 		}
651 		if (!old || pidff_needs_set_effect(effect, old))
652 			pidff_set_effect_report(pidff, effect);
653 		if (!old || pidff_needs_set_condition(effect, old))
654 			pidff_set_condition_report(pidff, effect);
655 		break;
656 
657 	case FF_FRICTION:
658 		if (!old) {
659 			error = pidff_request_effect_upload(pidff,
660 					pidff->type_id[PID_FRICTION]);
661 			if (error)
662 				return error;
663 		}
664 		if (!old || pidff_needs_set_effect(effect, old))
665 			pidff_set_effect_report(pidff, effect);
666 		if (!old || pidff_needs_set_condition(effect, old))
667 			pidff_set_condition_report(pidff, effect);
668 		break;
669 
670 	case FF_DAMPER:
671 		if (!old) {
672 			error = pidff_request_effect_upload(pidff,
673 					pidff->type_id[PID_DAMPER]);
674 			if (error)
675 				return error;
676 		}
677 		if (!old || pidff_needs_set_effect(effect, old))
678 			pidff_set_effect_report(pidff, effect);
679 		if (!old || pidff_needs_set_condition(effect, old))
680 			pidff_set_condition_report(pidff, effect);
681 		break;
682 
683 	case FF_INERTIA:
684 		if (!old) {
685 			error = pidff_request_effect_upload(pidff,
686 					pidff->type_id[PID_INERTIA]);
687 			if (error)
688 				return error;
689 		}
690 		if (!old || pidff_needs_set_effect(effect, old))
691 			pidff_set_effect_report(pidff, effect);
692 		if (!old || pidff_needs_set_condition(effect, old))
693 			pidff_set_condition_report(pidff, effect);
694 		break;
695 
696 	default:
697 		printk(KERN_ERR "hid-pidff: invalid type\n");
698 		return -EINVAL;
699 	}
700 
701 	if (!old)
702 		pidff->pid_id[effect->id] =
703 		    pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0];
704 
705 	debug("uploaded");
706 
707 	return 0;
708 }
709 
710 /*
711  * set_gain() handler
712  */
713 static void pidff_set_gain(struct input_dev *dev, u16 gain)
714 {
715 	struct pidff_device *pidff = dev->ff->private;
716 
717 	pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], gain);
718 	usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
719 			  USB_DIR_OUT);
720 }
721 
722 static void pidff_autocenter(struct pidff_device *pidff, u16 magnitude)
723 {
724 	struct hid_field *field =
725 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].field;
726 
727 	if (!magnitude) {
728 		pidff_playback_pid(pidff, field->logical_minimum, 0);
729 		return;
730 	}
731 
732 	pidff_playback_pid(pidff, field->logical_minimum, 1);
733 
734 	pidff->set_effect[PID_EFFECT_BLOCK_INDEX].value[0] =
735 		pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum;
736 	pidff->set_effect_type->value[0] = pidff->type_id[PID_SPRING];
737 	pidff->set_effect[PID_DURATION].value[0] = 0;
738 	pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = 0;
739 	pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] = 0;
740 	pidff_set(&pidff->set_effect[PID_GAIN], magnitude);
741 	pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
742 	pidff->set_effect[PID_START_DELAY].value[0] = 0;
743 
744 	usbhid_submit_report(pidff->hid, pidff->reports[PID_SET_EFFECT],
745 			  USB_DIR_OUT);
746 }
747 
748 /*
749  * pidff_set_autocenter() handler
750  */
751 static void pidff_set_autocenter(struct input_dev *dev, u16 magnitude)
752 {
753 	struct pidff_device *pidff = dev->ff->private;
754 
755 	pidff_autocenter(pidff, magnitude);
756 }
757 
758 /*
759  * Find fields from a report and fill a pidff_usage
760  */
761 static int pidff_find_fields(struct pidff_usage *usage, const u8 *table,
762 			     struct hid_report *report, int count, int strict)
763 {
764 	int i, j, k, found;
765 
766 	for (k = 0; k < count; k++) {
767 		found = 0;
768 		for (i = 0; i < report->maxfield; i++) {
769 			if (report->field[i]->maxusage !=
770 			    report->field[i]->report_count) {
771 				debug("maxusage and report_count do not match, "
772 				      "skipping");
773 				continue;
774 			}
775 			for (j = 0; j < report->field[i]->maxusage; j++) {
776 				if (report->field[i]->usage[j].hid ==
777 				    (HID_UP_PID | table[k])) {
778 					debug("found %d at %d->%d", k, i, j);
779 					usage[k].field = report->field[i];
780 					usage[k].value =
781 						&report->field[i]->value[j];
782 					found = 1;
783 					break;
784 				}
785 			}
786 			if (found)
787 				break;
788 		}
789 		if (!found && strict) {
790 			debug("failed to locate %d", k);
791 			return -1;
792 		}
793 	}
794 	return 0;
795 }
796 
797 /*
798  * Return index into pidff_reports for the given usage
799  */
800 static int pidff_check_usage(int usage)
801 {
802 	int i;
803 
804 	for (i = 0; i < sizeof(pidff_reports); i++)
805 		if (usage == (HID_UP_PID | pidff_reports[i]))
806 			return i;
807 
808 	return -1;
809 }
810 
811 /*
812  * Find the reports and fill pidff->reports[]
813  * report_type specifies either OUTPUT or FEATURE reports
814  */
815 static void pidff_find_reports(struct hid_device *hid, int report_type,
816 			       struct pidff_device *pidff)
817 {
818 	struct hid_report *report;
819 	int i, ret;
820 
821 	list_for_each_entry(report,
822 			    &hid->report_enum[report_type].report_list, list) {
823 		if (report->maxfield < 1)
824 			continue;
825 		ret = pidff_check_usage(report->field[0]->logical);
826 		if (ret != -1) {
827 			debug("found usage 0x%02x from field->logical",
828 			      pidff_reports[ret]);
829 			pidff->reports[ret] = report;
830 			continue;
831 		}
832 
833 		/*
834 		 * Sometimes logical collections are stacked to indicate
835 		 * different usages for the report and the field, in which
836 		 * case we want the usage of the parent. However, Linux HID
837 		 * implementation hides this fact, so we have to dig it up
838 		 * ourselves
839 		 */
840 		i = report->field[0]->usage[0].collection_index;
841 		if (i <= 0 ||
842 		    hid->collection[i - 1].type != HID_COLLECTION_LOGICAL)
843 			continue;
844 		ret = pidff_check_usage(hid->collection[i - 1].usage);
845 		if (ret != -1 && !pidff->reports[ret]) {
846 			debug("found usage 0x%02x from collection array",
847 			      pidff_reports[ret]);
848 			pidff->reports[ret] = report;
849 		}
850 	}
851 }
852 
853 /*
854  * Test if the required reports have been found
855  */
856 static int pidff_reports_ok(struct pidff_device *pidff)
857 {
858 	int i;
859 
860 	for (i = 0; i <= PID_REQUIRED_REPORTS; i++) {
861 		if (!pidff->reports[i]) {
862 			debug("%d missing", i);
863 			return 0;
864 		}
865 	}
866 
867 	return 1;
868 }
869 
870 /*
871  * Find a field with a specific usage within a report
872  */
873 static struct hid_field *pidff_find_special_field(struct hid_report *report,
874 						  int usage, int enforce_min)
875 {
876 	int i;
877 
878 	for (i = 0; i < report->maxfield; i++) {
879 		if (report->field[i]->logical == (HID_UP_PID | usage) &&
880 		    report->field[i]->report_count > 0) {
881 			if (!enforce_min ||
882 			    report->field[i]->logical_minimum == 1)
883 				return report->field[i];
884 			else {
885 				printk(KERN_ERR "hid-pidff: logical_minimum "
886 					"is not 1 as it should be\n");
887 				return NULL;
888 			}
889 		}
890 	}
891 	return NULL;
892 }
893 
894 /*
895  * Fill a pidff->*_id struct table
896  */
897 static int pidff_find_special_keys(int *keys, struct hid_field *fld,
898 				   const u8 *usagetable, int count)
899 {
900 
901 	int i, j;
902 	int found = 0;
903 
904 	for (i = 0; i < count; i++) {
905 		for (j = 0; j < fld->maxusage; j++) {
906 			if (fld->usage[j].hid == (HID_UP_PID | usagetable[i])) {
907 				keys[i] = j + 1;
908 				found++;
909 				break;
910 			}
911 		}
912 	}
913 	return found;
914 }
915 
916 #define PIDFF_FIND_SPECIAL_KEYS(keys, field, name) \
917 	pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
918 		sizeof(pidff_ ## name))
919 
920 /*
921  * Find and check the special fields
922  */
923 static int pidff_find_special_fields(struct pidff_device *pidff)
924 {
925 	debug("finding special fields");
926 
927 	pidff->create_new_effect_type =
928 		pidff_find_special_field(pidff->reports[PID_CREATE_NEW_EFFECT],
929 					 0x25, 1);
930 	pidff->set_effect_type =
931 		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
932 					 0x25, 1);
933 	pidff->effect_direction =
934 		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
935 					 0x57, 0);
936 	pidff->device_control =
937 		pidff_find_special_field(pidff->reports[PID_DEVICE_CONTROL],
938 					 0x96, 1);
939 	pidff->block_load_status =
940 		pidff_find_special_field(pidff->reports[PID_BLOCK_LOAD],
941 					 0x8b, 1);
942 	pidff->effect_operation_status =
943 		pidff_find_special_field(pidff->reports[PID_EFFECT_OPERATION],
944 					 0x78, 1);
945 
946 	debug("search done");
947 
948 	if (!pidff->create_new_effect_type || !pidff->set_effect_type) {
949 		printk(KERN_ERR "hid-pidff: effect lists not found\n");
950 		return -1;
951 	}
952 
953 	if (!pidff->effect_direction) {
954 		printk(KERN_ERR "hid-pidff: direction field not found\n");
955 		return -1;
956 	}
957 
958 	if (!pidff->device_control) {
959 		printk(KERN_ERR "hid-pidff: device control field not found\n");
960 		return -1;
961 	}
962 
963 	if (!pidff->block_load_status) {
964 		printk(KERN_ERR
965 		       "hid-pidff: block load status field not found\n");
966 		return -1;
967 	}
968 
969 	if (!pidff->effect_operation_status) {
970 		printk(KERN_ERR
971 		       "hid-pidff: effect operation field not found\n");
972 		return -1;
973 	}
974 
975 	pidff_find_special_keys(pidff->control_id, pidff->device_control,
976 				pidff_device_control,
977 				sizeof(pidff_device_control));
978 
979 	PIDFF_FIND_SPECIAL_KEYS(control_id, device_control, device_control);
980 
981 	if (!PIDFF_FIND_SPECIAL_KEYS(type_id, create_new_effect_type,
982 				     effect_types)) {
983 		printk(KERN_ERR "hid-pidff: no effect types found\n");
984 		return -1;
985 	}
986 
987 	if (PIDFF_FIND_SPECIAL_KEYS(status_id, block_load_status,
988 				    block_load_status) !=
989 			sizeof(pidff_block_load_status)) {
990 		printk(KERN_ERR
991 		       "hidpidff: block load status identifiers not found\n");
992 		return -1;
993 	}
994 
995 	if (PIDFF_FIND_SPECIAL_KEYS(operation_id, effect_operation_status,
996 				    effect_operation_status) !=
997 			sizeof(pidff_effect_operation_status)) {
998 		printk(KERN_ERR
999 		       "hidpidff: 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 			printk(KERN_ERR "hid-pidff: "
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 		printk(KERN_ERR
1075 		       "hid-pidff: unknown set_effect report layout\n");
1076 		return -ENODEV;
1077 	}
1078 
1079 	PIDFF_FIND_FIELDS(block_load, PID_BLOCK_LOAD, 0);
1080 	if (!pidff->block_load[PID_EFFECT_BLOCK_INDEX].value) {
1081 		printk(KERN_ERR
1082 		       "hid-pidff: unknown pid_block_load report layout\n");
1083 		return -ENODEV;
1084 	}
1085 
1086 	if (PIDFF_FIND_FIELDS(effect_operation, PID_EFFECT_OPERATION, 1)) {
1087 		printk(KERN_ERR
1088 		       "hid-pidff: unknown effect_operation report layout\n");
1089 		return -ENODEV;
1090 	}
1091 
1092 	if (PIDFF_FIND_FIELDS(block_free, PID_BLOCK_FREE, 1)) {
1093 		printk(KERN_ERR
1094 		       "hid-pidff: unknown pid_block_free report layout\n");
1095 		return -ENODEV;
1096 	}
1097 
1098 	if (!PIDFF_FIND_FIELDS(set_envelope, PID_SET_ENVELOPE, 1))
1099 		envelope_ok = 1;
1100 
1101 	if (pidff_find_special_fields(pidff) || pidff_find_effects(pidff, dev))
1102 		return -ENODEV;
1103 
1104 	if (!envelope_ok) {
1105 		if (test_and_clear_bit(FF_CONSTANT, dev->ffbit))
1106 			printk(KERN_WARNING "hid-pidff: "
1107 			       "has constant effect but no envelope\n");
1108 		if (test_and_clear_bit(FF_RAMP, dev->ffbit))
1109 			printk(KERN_WARNING "hid-pidff: "
1110 				"has ramp effect but no envelope\n");
1111 
1112 		if (test_and_clear_bit(FF_PERIODIC, dev->ffbit))
1113 			printk(KERN_WARNING "hid-pidff: "
1114 				"has periodic effect but no envelope\n");
1115 	}
1116 
1117 	if (test_bit(FF_CONSTANT, dev->ffbit) &&
1118 	    PIDFF_FIND_FIELDS(set_constant, PID_SET_CONSTANT, 1)) {
1119 		printk(KERN_WARNING
1120 		       "hid-pidff: unknown constant effect layout\n");
1121 		clear_bit(FF_CONSTANT, dev->ffbit);
1122 	}
1123 
1124 	if (test_bit(FF_RAMP, dev->ffbit) &&
1125 	    PIDFF_FIND_FIELDS(set_ramp, PID_SET_RAMP, 1)) {
1126 		printk(KERN_WARNING "hid-pidff: unknown ramp effect layout\n");
1127 		clear_bit(FF_RAMP, dev->ffbit);
1128 	}
1129 
1130 	if ((test_bit(FF_SPRING, dev->ffbit) ||
1131 	     test_bit(FF_DAMPER, dev->ffbit) ||
1132 	     test_bit(FF_FRICTION, dev->ffbit) ||
1133 	     test_bit(FF_INERTIA, dev->ffbit)) &&
1134 	    PIDFF_FIND_FIELDS(set_condition, PID_SET_CONDITION, 1)) {
1135 		printk(KERN_WARNING
1136 		       "hid-pidff: unknown condition effect layout\n");
1137 		clear_bit(FF_SPRING, dev->ffbit);
1138 		clear_bit(FF_DAMPER, dev->ffbit);
1139 		clear_bit(FF_FRICTION, dev->ffbit);
1140 		clear_bit(FF_INERTIA, dev->ffbit);
1141 	}
1142 
1143 	if (test_bit(FF_PERIODIC, dev->ffbit) &&
1144 	    PIDFF_FIND_FIELDS(set_periodic, PID_SET_PERIODIC, 1)) {
1145 		printk(KERN_WARNING
1146 		       "hid-pidff: unknown periodic effect layout\n");
1147 		clear_bit(FF_PERIODIC, dev->ffbit);
1148 	}
1149 
1150 	PIDFF_FIND_FIELDS(pool, PID_POOL, 0);
1151 
1152 	if (!PIDFF_FIND_FIELDS(device_gain, PID_DEVICE_GAIN, 1))
1153 		set_bit(FF_GAIN, dev->ffbit);
1154 
1155 	return 0;
1156 }
1157 
1158 /*
1159  * Reset the device
1160  */
1161 static void pidff_reset(struct pidff_device *pidff)
1162 {
1163 	struct hid_device *hid = pidff->hid;
1164 	int i = 0;
1165 
1166 	pidff->device_control->value[0] = pidff->control_id[PID_RESET];
1167 	/* We reset twice as sometimes hid_wait_io isn't waiting long enough */
1168 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1169 	usbhid_wait_io(hid);
1170 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1171 	usbhid_wait_io(hid);
1172 
1173 	pidff->device_control->value[0] =
1174 		pidff->control_id[PID_ENABLE_ACTUATORS];
1175 	usbhid_submit_report(hid, pidff->reports[PID_DEVICE_CONTROL], USB_DIR_OUT);
1176 	usbhid_wait_io(hid);
1177 
1178 	/* pool report is sometimes messed up, refetch it */
1179 	usbhid_submit_report(hid, pidff->reports[PID_POOL], USB_DIR_IN);
1180 	usbhid_wait_io(hid);
1181 
1182 	if (pidff->pool[PID_SIMULTANEOUS_MAX].value) {
1183 		int sim_effects = pidff->pool[PID_SIMULTANEOUS_MAX].value[0];
1184 		while (sim_effects < 2) {
1185 			if (i++ > 20) {
1186 				printk(KERN_WARNING "hid-pidff: device reports "
1187 				       "%d simultaneous effects\n",
1188 				       sim_effects);
1189 				break;
1190 			}
1191 			debug("pid_pool requested again");
1192 			usbhid_submit_report(hid, pidff->reports[PID_POOL],
1193 					  USB_DIR_IN);
1194 			usbhid_wait_io(hid);
1195 		}
1196 	}
1197 }
1198 
1199 /*
1200  * Test if autocenter modification is using the supported method
1201  */
1202 static int pidff_check_autocenter(struct pidff_device *pidff,
1203 				  struct input_dev *dev)
1204 {
1205 	int error;
1206 
1207 	/*
1208 	 * Let's find out if autocenter modification is supported
1209 	 * Specification doesn't specify anything, so we request an
1210 	 * effect upload and cancel it immediately. If the approved
1211 	 * effect id was one above the minimum, then we assume the first
1212 	 * effect id is a built-in spring type effect used for autocenter
1213 	 */
1214 
1215 	error = pidff_request_effect_upload(pidff, 1);
1216 	if (error) {
1217 		printk(KERN_ERR "hid-pidff: upload request failed\n");
1218 		return error;
1219 	}
1220 
1221 	if (pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0] ==
1222 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum + 1) {
1223 		pidff_autocenter(pidff, 0xffff);
1224 		set_bit(FF_AUTOCENTER, dev->ffbit);
1225 	} else {
1226 		printk(KERN_NOTICE "hid-pidff: "
1227 		       "device has unknown autocenter control method\n");
1228 	}
1229 
1230 	pidff_erase_pid(pidff,
1231 			pidff->block_load[PID_EFFECT_BLOCK_INDEX].value[0]);
1232 
1233 	return 0;
1234 
1235 }
1236 
1237 /*
1238  * Check if the device is PID and initialize it
1239  */
1240 int hid_pidff_init(struct hid_device *hid)
1241 {
1242 	struct pidff_device *pidff;
1243 	struct hid_input *hidinput = list_entry(hid->inputs.next,
1244 						struct hid_input, list);
1245 	struct input_dev *dev = hidinput->input;
1246 	struct ff_device *ff;
1247 	int max_effects;
1248 	int error;
1249 
1250 	debug("starting pid init");
1251 
1252 	if (list_empty(&hid->report_enum[HID_OUTPUT_REPORT].report_list)) {
1253 		debug("not a PID device, no output report");
1254 		return -ENODEV;
1255 	}
1256 
1257 	pidff = kzalloc(sizeof(*pidff), GFP_KERNEL);
1258 	if (!pidff)
1259 		return -ENOMEM;
1260 
1261 	pidff->hid = hid;
1262 
1263 	pidff_find_reports(hid, HID_OUTPUT_REPORT, pidff);
1264 	pidff_find_reports(hid, HID_FEATURE_REPORT, pidff);
1265 
1266 	if (!pidff_reports_ok(pidff)) {
1267 		debug("reports not ok, aborting");
1268 		error = -ENODEV;
1269 		goto fail;
1270 	}
1271 
1272 	error = pidff_init_fields(pidff, dev);
1273 	if (error)
1274 		goto fail;
1275 
1276 	pidff_reset(pidff);
1277 
1278 	if (test_bit(FF_GAIN, dev->ffbit)) {
1279 		pidff_set(&pidff->device_gain[PID_DEVICE_GAIN_FIELD], 0xffff);
1280 		usbhid_submit_report(pidff->hid, pidff->reports[PID_DEVICE_GAIN],
1281 				  USB_DIR_OUT);
1282 	}
1283 
1284 	error = pidff_check_autocenter(pidff, dev);
1285 	if (error)
1286 		goto fail;
1287 
1288 	max_effects =
1289 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_maximum -
1290 	    pidff->block_load[PID_EFFECT_BLOCK_INDEX].field->logical_minimum +
1291 	    1;
1292 	debug("max effects is %d", max_effects);
1293 
1294 	if (max_effects > PID_EFFECTS_MAX)
1295 		max_effects = PID_EFFECTS_MAX;
1296 
1297 	if (pidff->pool[PID_SIMULTANEOUS_MAX].value)
1298 		debug("max simultaneous effects is %d",
1299 		      pidff->pool[PID_SIMULTANEOUS_MAX].value[0]);
1300 
1301 	if (pidff->pool[PID_RAM_POOL_SIZE].value)
1302 		debug("device memory size is %d bytes",
1303 		      pidff->pool[PID_RAM_POOL_SIZE].value[0]);
1304 
1305 	if (pidff->pool[PID_DEVICE_MANAGED_POOL].value &&
1306 	    pidff->pool[PID_DEVICE_MANAGED_POOL].value[0] == 0) {
1307 		printk(KERN_NOTICE "hid-pidff: "
1308 		       "device does not support device managed pool\n");
1309 		goto fail;
1310 	}
1311 
1312 	error = input_ff_create(dev, max_effects);
1313 	if (error)
1314 		goto fail;
1315 
1316 	ff = dev->ff;
1317 	ff->private = pidff;
1318 	ff->upload = pidff_upload_effect;
1319 	ff->erase = pidff_erase_effect;
1320 	ff->set_gain = pidff_set_gain;
1321 	ff->set_autocenter = pidff_set_autocenter;
1322 	ff->playback = pidff_playback;
1323 
1324 	printk(KERN_INFO "Force feedback for USB HID PID devices by "
1325 	       "Anssi Hannula <anssi.hannula@gmail.com>\n");
1326 
1327 	return 0;
1328 
1329  fail:
1330 	kfree(pidff);
1331 	return error;
1332 }
1333