xref: /linux/drivers/hid/hid-lg4ff.c (revision 2da68a77)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  Force feedback support for Logitech Gaming Wheels
4  *
5  *  Including G27, G25, DFP, DFGT, FFEX, Momo, Momo2 &
6  *  Speed Force Wireless (WiiWheel)
7  *
8  *  Copyright (c) 2010 Simon Wood <simon@mungewell.org>
9  */
10 
11 /*
12  */
13 
14 
15 #include <linux/input.h>
16 #include <linux/usb.h>
17 #include <linux/hid.h>
18 
19 #include "usbhid/usbhid.h"
20 #include "hid-lg.h"
21 #include "hid-lg4ff.h"
22 #include "hid-ids.h"
23 
24 #define LG4FF_MMODE_IS_MULTIMODE 0
25 #define LG4FF_MMODE_SWITCHED 1
26 #define LG4FF_MMODE_NOT_MULTIMODE 2
27 
28 #define LG4FF_MODE_NATIVE_IDX 0
29 #define LG4FF_MODE_DFEX_IDX 1
30 #define LG4FF_MODE_DFP_IDX 2
31 #define LG4FF_MODE_G25_IDX 3
32 #define LG4FF_MODE_DFGT_IDX 4
33 #define LG4FF_MODE_G27_IDX 5
34 #define LG4FF_MODE_G29_IDX 6
35 #define LG4FF_MODE_MAX_IDX 7
36 
37 #define LG4FF_MODE_NATIVE BIT(LG4FF_MODE_NATIVE_IDX)
38 #define LG4FF_MODE_DFEX BIT(LG4FF_MODE_DFEX_IDX)
39 #define LG4FF_MODE_DFP BIT(LG4FF_MODE_DFP_IDX)
40 #define LG4FF_MODE_G25 BIT(LG4FF_MODE_G25_IDX)
41 #define LG4FF_MODE_DFGT BIT(LG4FF_MODE_DFGT_IDX)
42 #define LG4FF_MODE_G27 BIT(LG4FF_MODE_G27_IDX)
43 #define LG4FF_MODE_G29 BIT(LG4FF_MODE_G29_IDX)
44 
45 #define LG4FF_DFEX_TAG "DF-EX"
46 #define LG4FF_DFEX_NAME "Driving Force / Formula EX"
47 #define LG4FF_DFP_TAG "DFP"
48 #define LG4FF_DFP_NAME "Driving Force Pro"
49 #define LG4FF_G25_TAG "G25"
50 #define LG4FF_G25_NAME "G25 Racing Wheel"
51 #define LG4FF_G27_TAG "G27"
52 #define LG4FF_G27_NAME "G27 Racing Wheel"
53 #define LG4FF_G29_TAG "G29"
54 #define LG4FF_G29_NAME "G29 Racing Wheel"
55 #define LG4FF_DFGT_TAG "DFGT"
56 #define LG4FF_DFGT_NAME "Driving Force GT"
57 
58 #define LG4FF_FFEX_REV_MAJ 0x21
59 #define LG4FF_FFEX_REV_MIN 0x00
60 
61 static void lg4ff_set_range_dfp(struct hid_device *hid, u16 range);
62 static void lg4ff_set_range_g25(struct hid_device *hid, u16 range);
63 
64 struct lg4ff_wheel_data {
65 	const u32 product_id;
66 	u16 combine;
67 	u16 range;
68 	const u16 min_range;
69 	const u16 max_range;
70 #ifdef CONFIG_LEDS_CLASS
71 	u8  led_state;
72 	struct led_classdev *led[5];
73 #endif
74 	const u32 alternate_modes;
75 	const char * const real_tag;
76 	const char * const real_name;
77 	const u16 real_product_id;
78 
79 	void (*set_range)(struct hid_device *hid, u16 range);
80 };
81 
82 struct lg4ff_device_entry {
83 	spinlock_t report_lock; /* Protect output HID report */
84 	struct hid_report *report;
85 	struct lg4ff_wheel_data wdata;
86 };
87 
88 static const signed short lg4ff_wheel_effects[] = {
89 	FF_CONSTANT,
90 	FF_AUTOCENTER,
91 	-1
92 };
93 
94 static const signed short no_wheel_effects[] = {
95 	-1
96 };
97 
98 struct lg4ff_wheel {
99 	const u32 product_id;
100 	const signed short *ff_effects;
101 	const u16 min_range;
102 	const u16 max_range;
103 	void (*set_range)(struct hid_device *hid, u16 range);
104 };
105 
106 struct lg4ff_compat_mode_switch {
107 	const u8 cmd_count;	/* Number of commands to send */
108 	const u8 cmd[];
109 };
110 
111 struct lg4ff_wheel_ident_info {
112 	const u32 modes;
113 	const u16 mask;
114 	const u16 result;
115 	const u16 real_product_id;
116 };
117 
118 struct lg4ff_multimode_wheel {
119 	const u16 product_id;
120 	const u32 alternate_modes;
121 	const char *real_tag;
122 	const char *real_name;
123 };
124 
125 struct lg4ff_alternate_mode {
126 	const u16 product_id;
127 	const char *tag;
128 	const char *name;
129 };
130 
131 static const struct lg4ff_wheel lg4ff_devices[] = {
132 	{USB_DEVICE_ID_LOGITECH_WINGMAN_FG,  no_wheel_effects,    40, 180, NULL},
133 	{USB_DEVICE_ID_LOGITECH_WINGMAN_FFG, lg4ff_wheel_effects, 40, 180, NULL},
134 	{USB_DEVICE_ID_LOGITECH_WHEEL,       lg4ff_wheel_effects, 40, 270, NULL},
135 	{USB_DEVICE_ID_LOGITECH_MOMO_WHEEL,  lg4ff_wheel_effects, 40, 270, NULL},
136 	{USB_DEVICE_ID_LOGITECH_DFP_WHEEL,   lg4ff_wheel_effects, 40, 900, lg4ff_set_range_dfp},
137 	{USB_DEVICE_ID_LOGITECH_G25_WHEEL,   lg4ff_wheel_effects, 40, 900, lg4ff_set_range_g25},
138 	{USB_DEVICE_ID_LOGITECH_DFGT_WHEEL,  lg4ff_wheel_effects, 40, 900, lg4ff_set_range_g25},
139 	{USB_DEVICE_ID_LOGITECH_G27_WHEEL,   lg4ff_wheel_effects, 40, 900, lg4ff_set_range_g25},
140 	{USB_DEVICE_ID_LOGITECH_G29_WHEEL,   lg4ff_wheel_effects, 40, 900, lg4ff_set_range_g25},
141 	{USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2, lg4ff_wheel_effects, 40, 270, NULL},
142 	{USB_DEVICE_ID_LOGITECH_WII_WHEEL,   lg4ff_wheel_effects, 40, 270, NULL}
143 };
144 
145 static const struct lg4ff_multimode_wheel lg4ff_multimode_wheels[] = {
146 	{USB_DEVICE_ID_LOGITECH_DFP_WHEEL,
147 	 LG4FF_MODE_NATIVE | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
148 	 LG4FF_DFP_TAG, LG4FF_DFP_NAME},
149 	{USB_DEVICE_ID_LOGITECH_G25_WHEEL,
150 	 LG4FF_MODE_NATIVE | LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
151 	 LG4FF_G25_TAG, LG4FF_G25_NAME},
152 	{USB_DEVICE_ID_LOGITECH_DFGT_WHEEL,
153 	 LG4FF_MODE_NATIVE | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
154 	 LG4FF_DFGT_TAG, LG4FF_DFGT_NAME},
155 	{USB_DEVICE_ID_LOGITECH_G27_WHEEL,
156 	 LG4FF_MODE_NATIVE | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
157 	 LG4FF_G27_TAG, LG4FF_G27_NAME},
158 	{USB_DEVICE_ID_LOGITECH_G29_WHEEL,
159 	 LG4FF_MODE_NATIVE | LG4FF_MODE_G29 | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
160 	 LG4FF_G29_TAG, LG4FF_G29_NAME},
161 };
162 
163 static const struct lg4ff_alternate_mode lg4ff_alternate_modes[] = {
164 	[LG4FF_MODE_NATIVE_IDX] = {0, "native", ""},
165 	[LG4FF_MODE_DFEX_IDX] = {USB_DEVICE_ID_LOGITECH_WHEEL, LG4FF_DFEX_TAG, LG4FF_DFEX_NAME},
166 	[LG4FF_MODE_DFP_IDX] = {USB_DEVICE_ID_LOGITECH_DFP_WHEEL, LG4FF_DFP_TAG, LG4FF_DFP_NAME},
167 	[LG4FF_MODE_G25_IDX] = {USB_DEVICE_ID_LOGITECH_G25_WHEEL, LG4FF_G25_TAG, LG4FF_G25_NAME},
168 	[LG4FF_MODE_DFGT_IDX] = {USB_DEVICE_ID_LOGITECH_DFGT_WHEEL, LG4FF_DFGT_TAG, LG4FF_DFGT_NAME},
169 	[LG4FF_MODE_G27_IDX] = {USB_DEVICE_ID_LOGITECH_G27_WHEEL, LG4FF_G27_TAG, LG4FF_G27_NAME},
170 	[LG4FF_MODE_G29_IDX] = {USB_DEVICE_ID_LOGITECH_G29_WHEEL, LG4FF_G29_TAG, LG4FF_G29_NAME},
171 };
172 
173 /* Multimode wheel identificators */
174 static const struct lg4ff_wheel_ident_info lg4ff_dfp_ident_info = {
175 	LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
176 	0xf000,
177 	0x1000,
178 	USB_DEVICE_ID_LOGITECH_DFP_WHEEL
179 };
180 
181 static const struct lg4ff_wheel_ident_info lg4ff_g25_ident_info = {
182 	LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
183 	0xff00,
184 	0x1200,
185 	USB_DEVICE_ID_LOGITECH_G25_WHEEL
186 };
187 
188 static const struct lg4ff_wheel_ident_info lg4ff_g27_ident_info = {
189 	LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
190 	0xfff0,
191 	0x1230,
192 	USB_DEVICE_ID_LOGITECH_G27_WHEEL
193 };
194 
195 static const struct lg4ff_wheel_ident_info lg4ff_dfgt_ident_info = {
196 	LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
197 	0xff00,
198 	0x1300,
199 	USB_DEVICE_ID_LOGITECH_DFGT_WHEEL
200 };
201 
202 static const struct lg4ff_wheel_ident_info lg4ff_g29_ident_info = {
203 	LG4FF_MODE_G29 | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
204 	0xfff8,
205 	0x1350,
206 	USB_DEVICE_ID_LOGITECH_G29_WHEEL
207 };
208 
209 static const struct lg4ff_wheel_ident_info lg4ff_g29_ident_info2 = {
210 	LG4FF_MODE_G29 | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
211 	0xff00,
212 	0x8900,
213 	USB_DEVICE_ID_LOGITECH_G29_WHEEL
214 };
215 
216 /* Multimode wheel identification checklists */
217 static const struct lg4ff_wheel_ident_info *lg4ff_main_checklist[] = {
218 	&lg4ff_g29_ident_info,
219 	&lg4ff_g29_ident_info2,
220 	&lg4ff_dfgt_ident_info,
221 	&lg4ff_g27_ident_info,
222 	&lg4ff_g25_ident_info,
223 	&lg4ff_dfp_ident_info
224 };
225 
226 /* Compatibility mode switching commands */
227 /* EXT_CMD9 - Understood by G27 and DFGT */
228 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfex = {
229 	2,
230 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
231 	 0xf8, 0x09, 0x00, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to DF-EX with detach */
232 };
233 
234 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfp = {
235 	2,
236 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
237 	 0xf8, 0x09, 0x01, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to DFP with detach */
238 };
239 
240 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_g25 = {
241 	2,
242 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
243 	 0xf8, 0x09, 0x02, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to G25 with detach */
244 };
245 
246 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfgt = {
247 	2,
248 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
249 	 0xf8, 0x09, 0x03, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to DFGT with detach */
250 };
251 
252 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_g27 = {
253 	2,
254 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
255 	 0xf8, 0x09, 0x04, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to G27 with detach */
256 };
257 
258 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_g29 = {
259 	2,
260 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
261 	 0xf8, 0x09, 0x05, 0x01, 0x01, 0x00, 0x00}	/* Switch mode to G29 with detach */
262 };
263 
264 /* EXT_CMD1 - Understood by DFP, G25, G27 and DFGT */
265 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext01_dfp = {
266 	1,
267 	{0xf8, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00}
268 };
269 
270 /* EXT_CMD16 - Understood by G25 and G27 */
271 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext16_g25 = {
272 	1,
273 	{0xf8, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00}
274 };
275 
276 /* Recalculates X axis value accordingly to currently selected range */
277 static s32 lg4ff_adjust_dfp_x_axis(s32 value, u16 range)
278 {
279 	u16 max_range;
280 	s32 new_value;
281 
282 	if (range == 900)
283 		return value;
284 	else if (range == 200)
285 		return value;
286 	else if (range < 200)
287 		max_range = 200;
288 	else
289 		max_range = 900;
290 
291 	new_value = 8192 + mult_frac(value - 8192, max_range, range);
292 	if (new_value < 0)
293 		return 0;
294 	else if (new_value > 16383)
295 		return 16383;
296 	else
297 		return new_value;
298 }
299 
300 int lg4ff_adjust_input_event(struct hid_device *hid, struct hid_field *field,
301 			     struct hid_usage *usage, s32 value, struct lg_drv_data *drv_data)
302 {
303 	struct lg4ff_device_entry *entry = drv_data->device_props;
304 	s32 new_value = 0;
305 
306 	if (!entry) {
307 		hid_err(hid, "Device properties not found");
308 		return 0;
309 	}
310 
311 	switch (entry->wdata.product_id) {
312 	case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
313 		switch (usage->code) {
314 		case ABS_X:
315 			new_value = lg4ff_adjust_dfp_x_axis(value, entry->wdata.range);
316 			input_event(field->hidinput->input, usage->type, usage->code, new_value);
317 			return 1;
318 		default:
319 			return 0;
320 		}
321 	default:
322 		return 0;
323 	}
324 }
325 
326 int lg4ff_raw_event(struct hid_device *hdev, struct hid_report *report,
327 		u8 *rd, int size, struct lg_drv_data *drv_data)
328 {
329 	int offset;
330 	struct lg4ff_device_entry *entry = drv_data->device_props;
331 
332 	if (!entry)
333 		return 0;
334 
335 	/* adjust HID report present combined pedals data */
336 	if (entry->wdata.combine) {
337 		switch (entry->wdata.product_id) {
338 		case USB_DEVICE_ID_LOGITECH_WHEEL:
339 			rd[5] = rd[3];
340 			rd[6] = 0x7F;
341 			return 1;
342 		case USB_DEVICE_ID_LOGITECH_WINGMAN_FG:
343 		case USB_DEVICE_ID_LOGITECH_WINGMAN_FFG:
344 		case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL:
345 		case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2:
346 			rd[4] = rd[3];
347 			rd[5] = 0x7F;
348 			return 1;
349 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
350 			rd[5] = rd[4];
351 			rd[6] = 0x7F;
352 			return 1;
353 		case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
354 		case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
355 			offset = 5;
356 			break;
357 		case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
358 		case USB_DEVICE_ID_LOGITECH_G29_WHEEL:
359 			offset = 6;
360 			break;
361 		case USB_DEVICE_ID_LOGITECH_WII_WHEEL:
362 			offset = 3;
363 			break;
364 		default:
365 			return 0;
366 		}
367 
368 		/* Compute a combined axis when wheel does not supply it */
369 		rd[offset] = (0xFF + rd[offset] - rd[offset+1]) >> 1;
370 		rd[offset+1] = 0x7F;
371 		return 1;
372 	}
373 
374 	return 0;
375 }
376 
377 static void lg4ff_init_wheel_data(struct lg4ff_wheel_data * const wdata, const struct lg4ff_wheel *wheel,
378 				  const struct lg4ff_multimode_wheel *mmode_wheel,
379 				  const u16 real_product_id)
380 {
381 	u32 alternate_modes = 0;
382 	const char *real_tag = NULL;
383 	const char *real_name = NULL;
384 
385 	if (mmode_wheel) {
386 		alternate_modes = mmode_wheel->alternate_modes;
387 		real_tag = mmode_wheel->real_tag;
388 		real_name = mmode_wheel->real_name;
389 	}
390 
391 	{
392 		struct lg4ff_wheel_data t_wdata =  { .product_id = wheel->product_id,
393 						     .real_product_id = real_product_id,
394 						     .combine = 0,
395 						     .min_range = wheel->min_range,
396 						     .max_range = wheel->max_range,
397 						     .set_range = wheel->set_range,
398 						     .alternate_modes = alternate_modes,
399 						     .real_tag = real_tag,
400 						     .real_name = real_name };
401 
402 		memcpy(wdata, &t_wdata, sizeof(t_wdata));
403 	}
404 }
405 
406 static int lg4ff_play(struct input_dev *dev, void *data, struct ff_effect *effect)
407 {
408 	struct hid_device *hid = input_get_drvdata(dev);
409 	struct lg4ff_device_entry *entry;
410 	struct lg_drv_data *drv_data;
411 	unsigned long flags;
412 	s32 *value;
413 	int x;
414 
415 	drv_data = hid_get_drvdata(hid);
416 	if (!drv_data) {
417 		hid_err(hid, "Private driver data not found!\n");
418 		return -EINVAL;
419 	}
420 
421 	entry = drv_data->device_props;
422 	if (!entry) {
423 		hid_err(hid, "Device properties not found!\n");
424 		return -EINVAL;
425 	}
426 	value = entry->report->field[0]->value;
427 
428 #define CLAMP(x) do { if (x < 0) x = 0; else if (x > 0xff) x = 0xff; } while (0)
429 
430 	switch (effect->type) {
431 	case FF_CONSTANT:
432 		x = effect->u.ramp.start_level + 0x80;	/* 0x80 is no force */
433 		CLAMP(x);
434 
435 		spin_lock_irqsave(&entry->report_lock, flags);
436 		if (x == 0x80) {
437 			/* De-activate force in slot-1*/
438 			value[0] = 0x13;
439 			value[1] = 0x00;
440 			value[2] = 0x00;
441 			value[3] = 0x00;
442 			value[4] = 0x00;
443 			value[5] = 0x00;
444 			value[6] = 0x00;
445 
446 			hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
447 			spin_unlock_irqrestore(&entry->report_lock, flags);
448 			return 0;
449 		}
450 
451 		value[0] = 0x11;	/* Slot 1 */
452 		value[1] = 0x08;
453 		value[2] = x;
454 		value[3] = 0x80;
455 		value[4] = 0x00;
456 		value[5] = 0x00;
457 		value[6] = 0x00;
458 
459 		hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
460 		spin_unlock_irqrestore(&entry->report_lock, flags);
461 		break;
462 	}
463 	return 0;
464 }
465 
466 /* Sends default autocentering command compatible with
467  * all wheels except Formula Force EX */
468 static void lg4ff_set_autocenter_default(struct input_dev *dev, u16 magnitude)
469 {
470 	struct hid_device *hid = input_get_drvdata(dev);
471 	s32 *value;
472 	u32 expand_a, expand_b;
473 	struct lg4ff_device_entry *entry;
474 	struct lg_drv_data *drv_data;
475 	unsigned long flags;
476 
477 	drv_data = hid_get_drvdata(hid);
478 	if (!drv_data) {
479 		hid_err(hid, "Private driver data not found!\n");
480 		return;
481 	}
482 
483 	entry = drv_data->device_props;
484 	if (!entry) {
485 		hid_err(hid, "Device properties not found!\n");
486 		return;
487 	}
488 	value = entry->report->field[0]->value;
489 
490 	/* De-activate Auto-Center */
491 	spin_lock_irqsave(&entry->report_lock, flags);
492 	if (magnitude == 0) {
493 		value[0] = 0xf5;
494 		value[1] = 0x00;
495 		value[2] = 0x00;
496 		value[3] = 0x00;
497 		value[4] = 0x00;
498 		value[5] = 0x00;
499 		value[6] = 0x00;
500 
501 		hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
502 		spin_unlock_irqrestore(&entry->report_lock, flags);
503 		return;
504 	}
505 
506 	if (magnitude <= 0xaaaa) {
507 		expand_a = 0x0c * magnitude;
508 		expand_b = 0x80 * magnitude;
509 	} else {
510 		expand_a = (0x0c * 0xaaaa) + 0x06 * (magnitude - 0xaaaa);
511 		expand_b = (0x80 * 0xaaaa) + 0xff * (magnitude - 0xaaaa);
512 	}
513 
514 	/* Adjust for non-MOMO wheels */
515 	switch (entry->wdata.product_id) {
516 	case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL:
517 	case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2:
518 		break;
519 	default:
520 		expand_a = expand_a >> 1;
521 		break;
522 	}
523 
524 	value[0] = 0xfe;
525 	value[1] = 0x0d;
526 	value[2] = expand_a / 0xaaaa;
527 	value[3] = expand_a / 0xaaaa;
528 	value[4] = expand_b / 0xaaaa;
529 	value[5] = 0x00;
530 	value[6] = 0x00;
531 
532 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
533 
534 	/* Activate Auto-Center */
535 	value[0] = 0x14;
536 	value[1] = 0x00;
537 	value[2] = 0x00;
538 	value[3] = 0x00;
539 	value[4] = 0x00;
540 	value[5] = 0x00;
541 	value[6] = 0x00;
542 
543 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
544 	spin_unlock_irqrestore(&entry->report_lock, flags);
545 }
546 
547 /* Sends autocentering command compatible with Formula Force EX */
548 static void lg4ff_set_autocenter_ffex(struct input_dev *dev, u16 magnitude)
549 {
550 	struct hid_device *hid = input_get_drvdata(dev);
551 	struct lg4ff_device_entry *entry;
552 	struct lg_drv_data *drv_data;
553 	unsigned long flags;
554 	s32 *value;
555 	magnitude = magnitude * 90 / 65535;
556 
557 	drv_data = hid_get_drvdata(hid);
558 	if (!drv_data) {
559 		hid_err(hid, "Private driver data not found!\n");
560 		return;
561 	}
562 
563 	entry = drv_data->device_props;
564 	if (!entry) {
565 		hid_err(hid, "Device properties not found!\n");
566 		return;
567 	}
568 	value = entry->report->field[0]->value;
569 
570 	spin_lock_irqsave(&entry->report_lock, flags);
571 	value[0] = 0xfe;
572 	value[1] = 0x03;
573 	value[2] = magnitude >> 14;
574 	value[3] = magnitude >> 14;
575 	value[4] = magnitude;
576 	value[5] = 0x00;
577 	value[6] = 0x00;
578 
579 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
580 	spin_unlock_irqrestore(&entry->report_lock, flags);
581 }
582 
583 /* Sends command to set range compatible with G25/G27/Driving Force GT */
584 static void lg4ff_set_range_g25(struct hid_device *hid, u16 range)
585 {
586 	struct lg4ff_device_entry *entry;
587 	struct lg_drv_data *drv_data;
588 	unsigned long flags;
589 	s32 *value;
590 
591 	drv_data = hid_get_drvdata(hid);
592 	if (!drv_data) {
593 		hid_err(hid, "Private driver data not found!\n");
594 		return;
595 	}
596 
597 	entry = drv_data->device_props;
598 	if (!entry) {
599 		hid_err(hid, "Device properties not found!\n");
600 		return;
601 	}
602 	value = entry->report->field[0]->value;
603 	dbg_hid("G25/G27/DFGT: setting range to %u\n", range);
604 
605 	spin_lock_irqsave(&entry->report_lock, flags);
606 	value[0] = 0xf8;
607 	value[1] = 0x81;
608 	value[2] = range & 0x00ff;
609 	value[3] = (range & 0xff00) >> 8;
610 	value[4] = 0x00;
611 	value[5] = 0x00;
612 	value[6] = 0x00;
613 
614 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
615 	spin_unlock_irqrestore(&entry->report_lock, flags);
616 }
617 
618 /* Sends commands to set range compatible with Driving Force Pro wheel */
619 static void lg4ff_set_range_dfp(struct hid_device *hid, u16 range)
620 {
621 	struct lg4ff_device_entry *entry;
622 	struct lg_drv_data *drv_data;
623 	unsigned long flags;
624 	int start_left, start_right, full_range;
625 	s32 *value;
626 
627 	drv_data = hid_get_drvdata(hid);
628 	if (!drv_data) {
629 		hid_err(hid, "Private driver data not found!\n");
630 		return;
631 	}
632 
633 	entry = drv_data->device_props;
634 	if (!entry) {
635 		hid_err(hid, "Device properties not found!\n");
636 		return;
637 	}
638 	value = entry->report->field[0]->value;
639 	dbg_hid("Driving Force Pro: setting range to %u\n", range);
640 
641 	/* Prepare "coarse" limit command */
642 	spin_lock_irqsave(&entry->report_lock, flags);
643 	value[0] = 0xf8;
644 	value[1] = 0x00;	/* Set later */
645 	value[2] = 0x00;
646 	value[3] = 0x00;
647 	value[4] = 0x00;
648 	value[5] = 0x00;
649 	value[6] = 0x00;
650 
651 	if (range > 200) {
652 		value[1] = 0x03;
653 		full_range = 900;
654 	} else {
655 		value[1] = 0x02;
656 		full_range = 200;
657 	}
658 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
659 
660 	/* Prepare "fine" limit command */
661 	value[0] = 0x81;
662 	value[1] = 0x0b;
663 	value[2] = 0x00;
664 	value[3] = 0x00;
665 	value[4] = 0x00;
666 	value[5] = 0x00;
667 	value[6] = 0x00;
668 
669 	if (range == 200 || range == 900) {	/* Do not apply any fine limit */
670 		hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
671 		spin_unlock_irqrestore(&entry->report_lock, flags);
672 		return;
673 	}
674 
675 	/* Construct fine limit command */
676 	start_left = (((full_range - range + 1) * 2047) / full_range);
677 	start_right = 0xfff - start_left;
678 
679 	value[2] = start_left >> 4;
680 	value[3] = start_right >> 4;
681 	value[4] = 0xff;
682 	value[5] = (start_right & 0xe) << 4 | (start_left & 0xe);
683 	value[6] = 0xff;
684 
685 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
686 	spin_unlock_irqrestore(&entry->report_lock, flags);
687 }
688 
689 static const struct lg4ff_compat_mode_switch *lg4ff_get_mode_switch_command(const u16 real_product_id, const u16 target_product_id)
690 {
691 	switch (real_product_id) {
692 	case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
693 		switch (target_product_id) {
694 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
695 			return &lg4ff_mode_switch_ext01_dfp;
696 		/* DFP can only be switched to its native mode */
697 		default:
698 			return NULL;
699 		}
700 		break;
701 	case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
702 		switch (target_product_id) {
703 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
704 			return &lg4ff_mode_switch_ext01_dfp;
705 		case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
706 			return &lg4ff_mode_switch_ext16_g25;
707 		/* G25 can only be switched to DFP mode or its native mode */
708 		default:
709 			return NULL;
710 		}
711 		break;
712 	case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
713 		switch (target_product_id) {
714 		case USB_DEVICE_ID_LOGITECH_WHEEL:
715 			return &lg4ff_mode_switch_ext09_dfex;
716 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
717 			return &lg4ff_mode_switch_ext09_dfp;
718 		case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
719 			return &lg4ff_mode_switch_ext09_g25;
720 		case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
721 			return &lg4ff_mode_switch_ext09_g27;
722 		/* G27 can only be switched to DF-EX, DFP, G25 or its native mode */
723 		default:
724 			return NULL;
725 		}
726 		break;
727 	case USB_DEVICE_ID_LOGITECH_G29_WHEEL:
728 		switch (target_product_id) {
729 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
730 			return &lg4ff_mode_switch_ext09_dfp;
731 		case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
732 			return &lg4ff_mode_switch_ext09_dfgt;
733 		case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
734 			return &lg4ff_mode_switch_ext09_g25;
735 		case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
736 			return &lg4ff_mode_switch_ext09_g27;
737 		case USB_DEVICE_ID_LOGITECH_G29_WHEEL:
738 			return &lg4ff_mode_switch_ext09_g29;
739 		/* G29 can only be switched to DF-EX, DFP, DFGT, G25, G27 or its native mode */
740 		default:
741 			return NULL;
742 		}
743 		break;
744 	case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
745 		switch (target_product_id) {
746 		case USB_DEVICE_ID_LOGITECH_WHEEL:
747 			return &lg4ff_mode_switch_ext09_dfex;
748 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
749 			return &lg4ff_mode_switch_ext09_dfp;
750 		case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
751 			return &lg4ff_mode_switch_ext09_dfgt;
752 		/* DFGT can only be switched to DF-EX, DFP or its native mode */
753 		default:
754 			return NULL;
755 		}
756 		break;
757 	/* No other wheels have multiple modes */
758 	default:
759 		return NULL;
760 	}
761 }
762 
763 static int lg4ff_switch_compatibility_mode(struct hid_device *hid, const struct lg4ff_compat_mode_switch *s)
764 {
765 	struct lg4ff_device_entry *entry;
766 	struct lg_drv_data *drv_data;
767 	unsigned long flags;
768 	s32 *value;
769 	u8 i;
770 
771 	drv_data = hid_get_drvdata(hid);
772 	if (!drv_data) {
773 		hid_err(hid, "Private driver data not found!\n");
774 		return -EINVAL;
775 	}
776 
777 	entry = drv_data->device_props;
778 	if (!entry) {
779 		hid_err(hid, "Device properties not found!\n");
780 		return -EINVAL;
781 	}
782 	value = entry->report->field[0]->value;
783 
784 	spin_lock_irqsave(&entry->report_lock, flags);
785 	for (i = 0; i < s->cmd_count; i++) {
786 		u8 j;
787 
788 		for (j = 0; j < 7; j++)
789 			value[j] = s->cmd[j + (7*i)];
790 
791 		hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
792 	}
793 	spin_unlock_irqrestore(&entry->report_lock, flags);
794 	hid_hw_wait(hid);
795 	return 0;
796 }
797 
798 static ssize_t lg4ff_alternate_modes_show(struct device *dev, struct device_attribute *attr, char *buf)
799 {
800 	struct hid_device *hid = to_hid_device(dev);
801 	struct lg4ff_device_entry *entry;
802 	struct lg_drv_data *drv_data;
803 	ssize_t count = 0;
804 	int i;
805 
806 	drv_data = hid_get_drvdata(hid);
807 	if (!drv_data) {
808 		hid_err(hid, "Private driver data not found!\n");
809 		return 0;
810 	}
811 
812 	entry = drv_data->device_props;
813 	if (!entry) {
814 		hid_err(hid, "Device properties not found!\n");
815 		return 0;
816 	}
817 
818 	if (!entry->wdata.real_name) {
819 		hid_err(hid, "NULL pointer to string\n");
820 		return 0;
821 	}
822 
823 	for (i = 0; i < LG4FF_MODE_MAX_IDX; i++) {
824 		if (entry->wdata.alternate_modes & BIT(i)) {
825 			/* Print tag and full name */
826 			count += scnprintf(buf + count, PAGE_SIZE - count, "%s: %s",
827 					   lg4ff_alternate_modes[i].tag,
828 					   !lg4ff_alternate_modes[i].product_id ? entry->wdata.real_name : lg4ff_alternate_modes[i].name);
829 			if (count >= PAGE_SIZE - 1)
830 				return count;
831 
832 			/* Mark the currently active mode with an asterisk */
833 			if (lg4ff_alternate_modes[i].product_id == entry->wdata.product_id ||
834 			    (lg4ff_alternate_modes[i].product_id == 0 && entry->wdata.product_id == entry->wdata.real_product_id))
835 				count += scnprintf(buf + count, PAGE_SIZE - count, " *\n");
836 			else
837 				count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
838 
839 			if (count >= PAGE_SIZE - 1)
840 				return count;
841 		}
842 	}
843 
844 	return count;
845 }
846 
847 static ssize_t lg4ff_alternate_modes_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
848 {
849 	struct hid_device *hid = to_hid_device(dev);
850 	struct lg4ff_device_entry *entry;
851 	struct lg_drv_data *drv_data;
852 	const struct lg4ff_compat_mode_switch *s;
853 	u16 target_product_id = 0;
854 	int i, ret;
855 	char *lbuf;
856 
857 	drv_data = hid_get_drvdata(hid);
858 	if (!drv_data) {
859 		hid_err(hid, "Private driver data not found!\n");
860 		return -EINVAL;
861 	}
862 
863 	entry = drv_data->device_props;
864 	if (!entry) {
865 		hid_err(hid, "Device properties not found!\n");
866 		return -EINVAL;
867 	}
868 
869 	/* Allow \n at the end of the input parameter */
870 	lbuf = kasprintf(GFP_KERNEL, "%s", buf);
871 	if (!lbuf)
872 		return -ENOMEM;
873 
874 	i = strlen(lbuf);
875 
876 	if (i == 0) {
877 		kfree(lbuf);
878 		return -EINVAL;
879 	}
880 
881 	if (lbuf[i-1] == '\n') {
882 		if (i == 1) {
883 			kfree(lbuf);
884 			return -EINVAL;
885 		}
886 		lbuf[i-1] = '\0';
887 	}
888 
889 	for (i = 0; i < LG4FF_MODE_MAX_IDX; i++) {
890 		const u16 mode_product_id = lg4ff_alternate_modes[i].product_id;
891 		const char *tag = lg4ff_alternate_modes[i].tag;
892 
893 		if (entry->wdata.alternate_modes & BIT(i)) {
894 			if (!strcmp(tag, lbuf)) {
895 				if (!mode_product_id)
896 					target_product_id = entry->wdata.real_product_id;
897 				else
898 					target_product_id = mode_product_id;
899 				break;
900 			}
901 		}
902 	}
903 
904 	if (i == LG4FF_MODE_MAX_IDX) {
905 		hid_info(hid, "Requested mode \"%s\" is not supported by the device\n", lbuf);
906 		kfree(lbuf);
907 		return -EINVAL;
908 	}
909 	kfree(lbuf); /* Not needed anymore */
910 
911 	if (target_product_id == entry->wdata.product_id) /* Nothing to do */
912 		return count;
913 
914 	/* Automatic switching has to be disabled for the switch to DF-EX mode to work correctly */
915 	if (target_product_id == USB_DEVICE_ID_LOGITECH_WHEEL && !lg4ff_no_autoswitch) {
916 		hid_info(hid, "\"%s\" cannot be switched to \"DF-EX\" mode. Load the \"hid_logitech\" module with \"lg4ff_no_autoswitch=1\" parameter set and try again\n",
917 			 entry->wdata.real_name);
918 		return -EINVAL;
919 	}
920 
921 	/* Take care of hardware limitations */
922 	if ((entry->wdata.real_product_id == USB_DEVICE_ID_LOGITECH_DFP_WHEEL || entry->wdata.real_product_id == USB_DEVICE_ID_LOGITECH_G25_WHEEL) &&
923 	    entry->wdata.product_id > target_product_id) {
924 		hid_info(hid, "\"%s\" cannot be switched back into \"%s\" mode\n", entry->wdata.real_name, lg4ff_alternate_modes[i].name);
925 		return -EINVAL;
926 	}
927 
928 	s = lg4ff_get_mode_switch_command(entry->wdata.real_product_id, target_product_id);
929 	if (!s) {
930 		hid_err(hid, "Invalid target product ID %X\n", target_product_id);
931 		return -EINVAL;
932 	}
933 
934 	ret = lg4ff_switch_compatibility_mode(hid, s);
935 	return (ret == 0 ? count : ret);
936 }
937 static DEVICE_ATTR(alternate_modes, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH, lg4ff_alternate_modes_show, lg4ff_alternate_modes_store);
938 
939 static ssize_t lg4ff_combine_show(struct device *dev, struct device_attribute *attr,
940 				char *buf)
941 {
942 	struct hid_device *hid = to_hid_device(dev);
943 	struct lg4ff_device_entry *entry;
944 	struct lg_drv_data *drv_data;
945 	size_t count;
946 
947 	drv_data = hid_get_drvdata(hid);
948 	if (!drv_data) {
949 		hid_err(hid, "Private driver data not found!\n");
950 		return 0;
951 	}
952 
953 	entry = drv_data->device_props;
954 	if (!entry) {
955 		hid_err(hid, "Device properties not found!\n");
956 		return 0;
957 	}
958 
959 	count = scnprintf(buf, PAGE_SIZE, "%u\n", entry->wdata.combine);
960 	return count;
961 }
962 
963 static ssize_t lg4ff_combine_store(struct device *dev, struct device_attribute *attr,
964 				 const char *buf, size_t count)
965 {
966 	struct hid_device *hid = to_hid_device(dev);
967 	struct lg4ff_device_entry *entry;
968 	struct lg_drv_data *drv_data;
969 	u16 combine = simple_strtoul(buf, NULL, 10);
970 
971 	drv_data = hid_get_drvdata(hid);
972 	if (!drv_data) {
973 		hid_err(hid, "Private driver data not found!\n");
974 		return -EINVAL;
975 	}
976 
977 	entry = drv_data->device_props;
978 	if (!entry) {
979 		hid_err(hid, "Device properties not found!\n");
980 		return -EINVAL;
981 	}
982 
983 	if (combine > 1)
984 		combine = 1;
985 
986 	entry->wdata.combine = combine;
987 	return count;
988 }
989 static DEVICE_ATTR(combine_pedals, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH, lg4ff_combine_show, lg4ff_combine_store);
990 
991 /* Export the currently set range of the wheel */
992 static ssize_t lg4ff_range_show(struct device *dev, struct device_attribute *attr,
993 				char *buf)
994 {
995 	struct hid_device *hid = to_hid_device(dev);
996 	struct lg4ff_device_entry *entry;
997 	struct lg_drv_data *drv_data;
998 	size_t count;
999 
1000 	drv_data = hid_get_drvdata(hid);
1001 	if (!drv_data) {
1002 		hid_err(hid, "Private driver data not found!\n");
1003 		return 0;
1004 	}
1005 
1006 	entry = drv_data->device_props;
1007 	if (!entry) {
1008 		hid_err(hid, "Device properties not found!\n");
1009 		return 0;
1010 	}
1011 
1012 	count = scnprintf(buf, PAGE_SIZE, "%u\n", entry->wdata.range);
1013 	return count;
1014 }
1015 
1016 /* Set range to user specified value, call appropriate function
1017  * according to the type of the wheel */
1018 static ssize_t lg4ff_range_store(struct device *dev, struct device_attribute *attr,
1019 				 const char *buf, size_t count)
1020 {
1021 	struct hid_device *hid = to_hid_device(dev);
1022 	struct lg4ff_device_entry *entry;
1023 	struct lg_drv_data *drv_data;
1024 	u16 range = simple_strtoul(buf, NULL, 10);
1025 
1026 	drv_data = hid_get_drvdata(hid);
1027 	if (!drv_data) {
1028 		hid_err(hid, "Private driver data not found!\n");
1029 		return -EINVAL;
1030 	}
1031 
1032 	entry = drv_data->device_props;
1033 	if (!entry) {
1034 		hid_err(hid, "Device properties not found!\n");
1035 		return -EINVAL;
1036 	}
1037 
1038 	if (range == 0)
1039 		range = entry->wdata.max_range;
1040 
1041 	/* Check if the wheel supports range setting
1042 	 * and that the range is within limits for the wheel */
1043 	if (entry->wdata.set_range && range >= entry->wdata.min_range && range <= entry->wdata.max_range) {
1044 		entry->wdata.set_range(hid, range);
1045 		entry->wdata.range = range;
1046 	}
1047 
1048 	return count;
1049 }
1050 static DEVICE_ATTR(range, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH, lg4ff_range_show, lg4ff_range_store);
1051 
1052 static ssize_t lg4ff_real_id_show(struct device *dev, struct device_attribute *attr, char *buf)
1053 {
1054 	struct hid_device *hid = to_hid_device(dev);
1055 	struct lg4ff_device_entry *entry;
1056 	struct lg_drv_data *drv_data;
1057 	size_t count;
1058 
1059 	drv_data = hid_get_drvdata(hid);
1060 	if (!drv_data) {
1061 		hid_err(hid, "Private driver data not found!\n");
1062 		return 0;
1063 	}
1064 
1065 	entry = drv_data->device_props;
1066 	if (!entry) {
1067 		hid_err(hid, "Device properties not found!\n");
1068 		return 0;
1069 	}
1070 
1071 	if (!entry->wdata.real_tag || !entry->wdata.real_name) {
1072 		hid_err(hid, "NULL pointer to string\n");
1073 		return 0;
1074 	}
1075 
1076 	count = scnprintf(buf, PAGE_SIZE, "%s: %s\n", entry->wdata.real_tag, entry->wdata.real_name);
1077 	return count;
1078 }
1079 
1080 static ssize_t lg4ff_real_id_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
1081 {
1082 	/* Real ID is a read-only value */
1083 	return -EPERM;
1084 }
1085 static DEVICE_ATTR(real_id, S_IRUGO, lg4ff_real_id_show, lg4ff_real_id_store);
1086 
1087 #ifdef CONFIG_LEDS_CLASS
1088 static void lg4ff_set_leds(struct hid_device *hid, u8 leds)
1089 {
1090 	struct lg_drv_data *drv_data;
1091 	struct lg4ff_device_entry *entry;
1092 	unsigned long flags;
1093 	s32 *value;
1094 
1095 	drv_data = hid_get_drvdata(hid);
1096 	if (!drv_data) {
1097 		hid_err(hid, "Private driver data not found!\n");
1098 		return;
1099 	}
1100 
1101 	entry = drv_data->device_props;
1102 	if (!entry) {
1103 		hid_err(hid, "Device properties not found!\n");
1104 		return;
1105 	}
1106 	value = entry->report->field[0]->value;
1107 
1108 	spin_lock_irqsave(&entry->report_lock, flags);
1109 	value[0] = 0xf8;
1110 	value[1] = 0x12;
1111 	value[2] = leds;
1112 	value[3] = 0x00;
1113 	value[4] = 0x00;
1114 	value[5] = 0x00;
1115 	value[6] = 0x00;
1116 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
1117 	spin_unlock_irqrestore(&entry->report_lock, flags);
1118 }
1119 
1120 static void lg4ff_led_set_brightness(struct led_classdev *led_cdev,
1121 			enum led_brightness value)
1122 {
1123 	struct device *dev = led_cdev->dev->parent;
1124 	struct hid_device *hid = to_hid_device(dev);
1125 	struct lg_drv_data *drv_data = hid_get_drvdata(hid);
1126 	struct lg4ff_device_entry *entry;
1127 	int i, state = 0;
1128 
1129 	if (!drv_data) {
1130 		hid_err(hid, "Device data not found.");
1131 		return;
1132 	}
1133 
1134 	entry = drv_data->device_props;
1135 
1136 	if (!entry) {
1137 		hid_err(hid, "Device properties not found.");
1138 		return;
1139 	}
1140 
1141 	for (i = 0; i < 5; i++) {
1142 		if (led_cdev != entry->wdata.led[i])
1143 			continue;
1144 		state = (entry->wdata.led_state >> i) & 1;
1145 		if (value == LED_OFF && state) {
1146 			entry->wdata.led_state &= ~(1 << i);
1147 			lg4ff_set_leds(hid, entry->wdata.led_state);
1148 		} else if (value != LED_OFF && !state) {
1149 			entry->wdata.led_state |= 1 << i;
1150 			lg4ff_set_leds(hid, entry->wdata.led_state);
1151 		}
1152 		break;
1153 	}
1154 }
1155 
1156 static enum led_brightness lg4ff_led_get_brightness(struct led_classdev *led_cdev)
1157 {
1158 	struct device *dev = led_cdev->dev->parent;
1159 	struct hid_device *hid = to_hid_device(dev);
1160 	struct lg_drv_data *drv_data = hid_get_drvdata(hid);
1161 	struct lg4ff_device_entry *entry;
1162 	int i, value = 0;
1163 
1164 	if (!drv_data) {
1165 		hid_err(hid, "Device data not found.");
1166 		return LED_OFF;
1167 	}
1168 
1169 	entry = drv_data->device_props;
1170 
1171 	if (!entry) {
1172 		hid_err(hid, "Device properties not found.");
1173 		return LED_OFF;
1174 	}
1175 
1176 	for (i = 0; i < 5; i++)
1177 		if (led_cdev == entry->wdata.led[i]) {
1178 			value = (entry->wdata.led_state >> i) & 1;
1179 			break;
1180 		}
1181 
1182 	return value ? LED_FULL : LED_OFF;
1183 }
1184 #endif
1185 
1186 static u16 lg4ff_identify_multimode_wheel(struct hid_device *hid, const u16 reported_product_id, const u16 bcdDevice)
1187 {
1188 	u32 current_mode;
1189 	int i;
1190 
1191 	/* identify current mode from USB PID */
1192 	for (i = 1; i < ARRAY_SIZE(lg4ff_alternate_modes); i++) {
1193 		dbg_hid("Testing whether PID is %X\n", lg4ff_alternate_modes[i].product_id);
1194 		if (reported_product_id == lg4ff_alternate_modes[i].product_id)
1195 			break;
1196 	}
1197 
1198 	if (i == ARRAY_SIZE(lg4ff_alternate_modes))
1199 		return 0;
1200 
1201 	current_mode = BIT(i);
1202 
1203 	for (i = 0; i < ARRAY_SIZE(lg4ff_main_checklist); i++) {
1204 		const u16 mask = lg4ff_main_checklist[i]->mask;
1205 		const u16 result = lg4ff_main_checklist[i]->result;
1206 		const u16 real_product_id = lg4ff_main_checklist[i]->real_product_id;
1207 
1208 		if ((current_mode & lg4ff_main_checklist[i]->modes) && \
1209 				(bcdDevice & mask) == result) {
1210 			dbg_hid("Found wheel with real PID %X whose reported PID is %X\n", real_product_id, reported_product_id);
1211 			return real_product_id;
1212 		}
1213 	}
1214 
1215 	/* No match found. This is either Driving Force or an unknown
1216 	 * wheel model, do not touch it */
1217 	dbg_hid("Wheel with bcdDevice %X was not recognized as multimode wheel, leaving in its current mode\n", bcdDevice);
1218 	return 0;
1219 }
1220 
1221 static int lg4ff_handle_multimode_wheel(struct hid_device *hid, u16 *real_product_id, const u16 bcdDevice)
1222 {
1223 	const u16 reported_product_id = hid->product;
1224 	int ret;
1225 
1226 	*real_product_id = lg4ff_identify_multimode_wheel(hid, reported_product_id, bcdDevice);
1227 	/* Probed wheel is not a multimode wheel */
1228 	if (!*real_product_id) {
1229 		*real_product_id = reported_product_id;
1230 		dbg_hid("Wheel is not a multimode wheel\n");
1231 		return LG4FF_MMODE_NOT_MULTIMODE;
1232 	}
1233 
1234 	/* Switch from "Driving Force" mode to native mode automatically.
1235 	 * Otherwise keep the wheel in its current mode */
1236 	if (reported_product_id == USB_DEVICE_ID_LOGITECH_WHEEL &&
1237 	    reported_product_id != *real_product_id &&
1238 	    !lg4ff_no_autoswitch) {
1239 		const struct lg4ff_compat_mode_switch *s = lg4ff_get_mode_switch_command(*real_product_id, *real_product_id);
1240 
1241 		if (!s) {
1242 			hid_err(hid, "Invalid product id %X\n", *real_product_id);
1243 			return LG4FF_MMODE_NOT_MULTIMODE;
1244 		}
1245 
1246 		ret = lg4ff_switch_compatibility_mode(hid, s);
1247 		if (ret) {
1248 			/* Wheel could not have been switched to native mode,
1249 			 * leave it in "Driving Force" mode and continue */
1250 			hid_err(hid, "Unable to switch wheel mode, errno %d\n", ret);
1251 			return LG4FF_MMODE_IS_MULTIMODE;
1252 		}
1253 		return LG4FF_MMODE_SWITCHED;
1254 	}
1255 
1256 	return LG4FF_MMODE_IS_MULTIMODE;
1257 }
1258 
1259 
1260 int lg4ff_init(struct hid_device *hid)
1261 {
1262 	struct hid_input *hidinput;
1263 	struct input_dev *dev;
1264 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
1265 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
1266 	const struct usb_device_descriptor *udesc = &(hid_to_usb_dev(hid)->descriptor);
1267 	const u16 bcdDevice = le16_to_cpu(udesc->bcdDevice);
1268 	const struct lg4ff_multimode_wheel *mmode_wheel = NULL;
1269 	struct lg4ff_device_entry *entry;
1270 	struct lg_drv_data *drv_data;
1271 	int error, i, j;
1272 	int mmode_ret, mmode_idx = -1;
1273 	u16 real_product_id;
1274 
1275 	if (list_empty(&hid->inputs)) {
1276 		hid_err(hid, "no inputs found\n");
1277 		return -ENODEV;
1278 	}
1279 	hidinput = list_entry(hid->inputs.next, struct hid_input, list);
1280 	dev = hidinput->input;
1281 
1282 	/* Check that the report looks ok */
1283 	if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
1284 		return -1;
1285 
1286 	drv_data = hid_get_drvdata(hid);
1287 	if (!drv_data) {
1288 		hid_err(hid, "Cannot add device, private driver data not allocated\n");
1289 		return -1;
1290 	}
1291 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1292 	if (!entry)
1293 		return -ENOMEM;
1294 	spin_lock_init(&entry->report_lock);
1295 	entry->report = report;
1296 	drv_data->device_props = entry;
1297 
1298 	/* Check if a multimode wheel has been connected and
1299 	 * handle it appropriately */
1300 	mmode_ret = lg4ff_handle_multimode_wheel(hid, &real_product_id, bcdDevice);
1301 
1302 	/* Wheel has been told to switch to native mode. There is no point in going on
1303 	 * with the initialization as the wheel will do a USB reset when it switches mode
1304 	 */
1305 	if (mmode_ret == LG4FF_MMODE_SWITCHED)
1306 		return 0;
1307 	else if (mmode_ret < 0) {
1308 		hid_err(hid, "Unable to switch device mode during initialization, errno %d\n", mmode_ret);
1309 		error = mmode_ret;
1310 		goto err_init;
1311 	}
1312 
1313 	/* Check what wheel has been connected */
1314 	for (i = 0; i < ARRAY_SIZE(lg4ff_devices); i++) {
1315 		if (hid->product == lg4ff_devices[i].product_id) {
1316 			dbg_hid("Found compatible device, product ID %04X\n", lg4ff_devices[i].product_id);
1317 			break;
1318 		}
1319 	}
1320 
1321 	if (i == ARRAY_SIZE(lg4ff_devices)) {
1322 		hid_err(hid, "This device is flagged to be handled by the lg4ff module but this module does not know how to handle it. "
1323 			     "Please report this as a bug to LKML, Simon Wood <simon@mungewell.org> or "
1324 			     "Michal Maly <madcatxster@devoid-pointer.net>\n");
1325 		error = -1;
1326 		goto err_init;
1327 	}
1328 
1329 	if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
1330 		for (mmode_idx = 0; mmode_idx < ARRAY_SIZE(lg4ff_multimode_wheels); mmode_idx++) {
1331 			if (real_product_id == lg4ff_multimode_wheels[mmode_idx].product_id)
1332 				break;
1333 		}
1334 
1335 		if (mmode_idx == ARRAY_SIZE(lg4ff_multimode_wheels)) {
1336 			hid_err(hid, "Device product ID %X is not listed as a multimode wheel", real_product_id);
1337 			error = -1;
1338 			goto err_init;
1339 		}
1340 	}
1341 
1342 	/* Set supported force feedback capabilities */
1343 	for (j = 0; lg4ff_devices[i].ff_effects[j] >= 0; j++)
1344 		set_bit(lg4ff_devices[i].ff_effects[j], dev->ffbit);
1345 
1346 	error = input_ff_create_memless(dev, NULL, lg4ff_play);
1347 
1348 	if (error)
1349 		goto err_init;
1350 
1351 	/* Initialize device properties */
1352 	if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
1353 		BUG_ON(mmode_idx == -1);
1354 		mmode_wheel = &lg4ff_multimode_wheels[mmode_idx];
1355 	}
1356 	lg4ff_init_wheel_data(&entry->wdata, &lg4ff_devices[i], mmode_wheel, real_product_id);
1357 
1358 	/* Check if autocentering is available and
1359 	 * set the centering force to zero by default */
1360 	if (test_bit(FF_AUTOCENTER, dev->ffbit)) {
1361 		/* Formula Force EX expects different autocentering command */
1362 		if ((bcdDevice >> 8) == LG4FF_FFEX_REV_MAJ &&
1363 		    (bcdDevice & 0xff) == LG4FF_FFEX_REV_MIN)
1364 			dev->ff->set_autocenter = lg4ff_set_autocenter_ffex;
1365 		else
1366 			dev->ff->set_autocenter = lg4ff_set_autocenter_default;
1367 
1368 		dev->ff->set_autocenter(dev, 0);
1369 	}
1370 
1371 	/* Create sysfs interface */
1372 	error = device_create_file(&hid->dev, &dev_attr_combine_pedals);
1373 	if (error)
1374 		hid_warn(hid, "Unable to create sysfs interface for \"combine\", errno %d\n", error);
1375 	error = device_create_file(&hid->dev, &dev_attr_range);
1376 	if (error)
1377 		hid_warn(hid, "Unable to create sysfs interface for \"range\", errno %d\n", error);
1378 	if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
1379 		error = device_create_file(&hid->dev, &dev_attr_real_id);
1380 		if (error)
1381 			hid_warn(hid, "Unable to create sysfs interface for \"real_id\", errno %d\n", error);
1382 		error = device_create_file(&hid->dev, &dev_attr_alternate_modes);
1383 		if (error)
1384 			hid_warn(hid, "Unable to create sysfs interface for \"alternate_modes\", errno %d\n", error);
1385 	}
1386 	dbg_hid("sysfs interface created\n");
1387 
1388 	/* Set the maximum range to start with */
1389 	entry->wdata.range = entry->wdata.max_range;
1390 	if (entry->wdata.set_range)
1391 		entry->wdata.set_range(hid, entry->wdata.range);
1392 
1393 #ifdef CONFIG_LEDS_CLASS
1394 	/* register led subsystem - G27/G29 only */
1395 	entry->wdata.led_state = 0;
1396 	for (j = 0; j < 5; j++)
1397 		entry->wdata.led[j] = NULL;
1398 
1399 	if (lg4ff_devices[i].product_id == USB_DEVICE_ID_LOGITECH_G27_WHEEL ||
1400 			lg4ff_devices[i].product_id == USB_DEVICE_ID_LOGITECH_G29_WHEEL) {
1401 		struct led_classdev *led;
1402 		size_t name_sz;
1403 		char *name;
1404 
1405 		lg4ff_set_leds(hid, 0);
1406 
1407 		name_sz = strlen(dev_name(&hid->dev)) + 8;
1408 
1409 		for (j = 0; j < 5; j++) {
1410 			led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
1411 			if (!led) {
1412 				hid_err(hid, "can't allocate memory for LED %d\n", j);
1413 				goto err_leds;
1414 			}
1415 
1416 			name = (void *)(&led[1]);
1417 			snprintf(name, name_sz, "%s::RPM%d", dev_name(&hid->dev), j+1);
1418 			led->name = name;
1419 			led->brightness = 0;
1420 			led->max_brightness = 1;
1421 			led->brightness_get = lg4ff_led_get_brightness;
1422 			led->brightness_set = lg4ff_led_set_brightness;
1423 
1424 			entry->wdata.led[j] = led;
1425 			error = led_classdev_register(&hid->dev, led);
1426 
1427 			if (error) {
1428 				hid_err(hid, "failed to register LED %d. Aborting.\n", j);
1429 err_leds:
1430 				/* Deregister LEDs (if any) */
1431 				for (j = 0; j < 5; j++) {
1432 					led = entry->wdata.led[j];
1433 					entry->wdata.led[j] = NULL;
1434 					if (!led)
1435 						continue;
1436 					led_classdev_unregister(led);
1437 					kfree(led);
1438 				}
1439 				goto out;	/* Let the driver continue without LEDs */
1440 			}
1441 		}
1442 	}
1443 out:
1444 #endif
1445 	hid_info(hid, "Force feedback support for Logitech Gaming Wheels\n");
1446 	return 0;
1447 
1448 err_init:
1449 	drv_data->device_props = NULL;
1450 	kfree(entry);
1451 	return error;
1452 }
1453 
1454 int lg4ff_deinit(struct hid_device *hid)
1455 {
1456 	struct lg4ff_device_entry *entry;
1457 	struct lg_drv_data *drv_data;
1458 
1459 	drv_data = hid_get_drvdata(hid);
1460 	if (!drv_data) {
1461 		hid_err(hid, "Error while deinitializing device, no private driver data.\n");
1462 		return -1;
1463 	}
1464 	entry = drv_data->device_props;
1465 	if (!entry)
1466 		goto out; /* Nothing more to do */
1467 
1468 	/* Multimode devices will have at least the "MODE_NATIVE" bit set */
1469 	if (entry->wdata.alternate_modes) {
1470 		device_remove_file(&hid->dev, &dev_attr_real_id);
1471 		device_remove_file(&hid->dev, &dev_attr_alternate_modes);
1472 	}
1473 
1474 	device_remove_file(&hid->dev, &dev_attr_combine_pedals);
1475 	device_remove_file(&hid->dev, &dev_attr_range);
1476 #ifdef CONFIG_LEDS_CLASS
1477 	{
1478 		int j;
1479 		struct led_classdev *led;
1480 
1481 		/* Deregister LEDs (if any) */
1482 		for (j = 0; j < 5; j++) {
1483 
1484 			led = entry->wdata.led[j];
1485 			entry->wdata.led[j] = NULL;
1486 			if (!led)
1487 				continue;
1488 			led_classdev_unregister(led);
1489 			kfree(led);
1490 		}
1491 	}
1492 #endif
1493 	drv_data->device_props = NULL;
1494 
1495 	kfree(entry);
1496 out:
1497 	dbg_hid("Device successfully unregistered\n");
1498 	return 0;
1499 }
1500