xref: /openbmc/linux/drivers/hid/hid-lg4ff.c (revision 9da8320b)
1 /*
2  *  Force feedback support for Logitech Gaming Wheels
3  *
4  *  Including G27, G25, DFP, DFGT, FFEX, Momo, Momo2 &
5  *  Speed Force Wireless (WiiWheel)
6  *
7  *  Copyright (c) 2010 Simon Wood <simon@mungewell.org>
8  */
9 
10 /*
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or
14  * (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
24  */
25 
26 
27 #include <linux/input.h>
28 #include <linux/usb.h>
29 #include <linux/hid.h>
30 
31 #include "usbhid/usbhid.h"
32 #include "hid-lg.h"
33 #include "hid-lg4ff.h"
34 #include "hid-ids.h"
35 
36 #define to_hid_device(pdev) container_of(pdev, struct hid_device, dev)
37 
38 #define LG4FF_MMODE_IS_MULTIMODE 0
39 #define LG4FF_MMODE_SWITCHED 1
40 #define LG4FF_MMODE_NOT_MULTIMODE 2
41 
42 #define LG4FF_MODE_NATIVE_IDX 0
43 #define LG4FF_MODE_DFEX_IDX 1
44 #define LG4FF_MODE_DFP_IDX 2
45 #define LG4FF_MODE_G25_IDX 3
46 #define LG4FF_MODE_DFGT_IDX 4
47 #define LG4FF_MODE_G27_IDX 5
48 #define LG4FF_MODE_G29_IDX 6
49 #define LG4FF_MODE_MAX_IDX 7
50 
51 #define LG4FF_MODE_NATIVE BIT(LG4FF_MODE_NATIVE_IDX)
52 #define LG4FF_MODE_DFEX BIT(LG4FF_MODE_DFEX_IDX)
53 #define LG4FF_MODE_DFP BIT(LG4FF_MODE_DFP_IDX)
54 #define LG4FF_MODE_G25 BIT(LG4FF_MODE_G25_IDX)
55 #define LG4FF_MODE_DFGT BIT(LG4FF_MODE_DFGT_IDX)
56 #define LG4FF_MODE_G27 BIT(LG4FF_MODE_G27_IDX)
57 #define LG4FF_MODE_G29 BIT(LG4FF_MODE_G29_IDX)
58 
59 #define LG4FF_DFEX_TAG "DF-EX"
60 #define LG4FF_DFEX_NAME "Driving Force / Formula EX"
61 #define LG4FF_DFP_TAG "DFP"
62 #define LG4FF_DFP_NAME "Driving Force Pro"
63 #define LG4FF_G25_TAG "G25"
64 #define LG4FF_G25_NAME "G25 Racing Wheel"
65 #define LG4FF_G27_TAG "G27"
66 #define LG4FF_G27_NAME "G27 Racing Wheel"
67 #define LG4FF_G29_TAG "G29"
68 #define LG4FF_G29_NAME "G29 Racing Wheel"
69 #define LG4FF_DFGT_TAG "DFGT"
70 #define LG4FF_DFGT_NAME "Driving Force GT"
71 
72 #define LG4FF_FFEX_REV_MAJ 0x21
73 #define LG4FF_FFEX_REV_MIN 0x00
74 
75 static void lg4ff_set_range_dfp(struct hid_device *hid, u16 range);
76 static void lg4ff_set_range_g25(struct hid_device *hid, u16 range);
77 
78 struct lg4ff_wheel_data {
79 	const u32 product_id;
80 	u16 range;
81 	const u16 min_range;
82 	const u16 max_range;
83 #ifdef CONFIG_LEDS_CLASS
84 	u8  led_state;
85 	struct led_classdev *led[5];
86 #endif
87 	const u32 alternate_modes;
88 	const char * const real_tag;
89 	const char * const real_name;
90 	const u16 real_product_id;
91 
92 	void (*set_range)(struct hid_device *hid, u16 range);
93 };
94 
95 struct lg4ff_device_entry {
96 	spinlock_t report_lock; /* Protect output HID report */
97 	struct hid_report *report;
98 	struct lg4ff_wheel_data wdata;
99 };
100 
101 static const signed short lg4ff_wheel_effects[] = {
102 	FF_CONSTANT,
103 	FF_AUTOCENTER,
104 	-1
105 };
106 
107 struct lg4ff_wheel {
108 	const u32 product_id;
109 	const signed short *ff_effects;
110 	const u16 min_range;
111 	const u16 max_range;
112 	void (*set_range)(struct hid_device *hid, u16 range);
113 };
114 
115 struct lg4ff_compat_mode_switch {
116 	const u8 cmd_count;	/* Number of commands to send */
117 	const u8 cmd[];
118 };
119 
120 struct lg4ff_wheel_ident_info {
121 	const u32 modes;
122 	const u16 mask;
123 	const u16 result;
124 	const u16 real_product_id;
125 };
126 
127 struct lg4ff_multimode_wheel {
128 	const u16 product_id;
129 	const u32 alternate_modes;
130 	const char *real_tag;
131 	const char *real_name;
132 };
133 
134 struct lg4ff_alternate_mode {
135 	const u16 product_id;
136 	const char *tag;
137 	const char *name;
138 };
139 
140 static const struct lg4ff_wheel lg4ff_devices[] = {
141 	{USB_DEVICE_ID_LOGITECH_WHEEL,       lg4ff_wheel_effects, 40, 270, NULL},
142 	{USB_DEVICE_ID_LOGITECH_MOMO_WHEEL,  lg4ff_wheel_effects, 40, 270, NULL},
143 	{USB_DEVICE_ID_LOGITECH_DFP_WHEEL,   lg4ff_wheel_effects, 40, 900, lg4ff_set_range_dfp},
144 	{USB_DEVICE_ID_LOGITECH_G25_WHEEL,   lg4ff_wheel_effects, 40, 900, lg4ff_set_range_g25},
145 	{USB_DEVICE_ID_LOGITECH_DFGT_WHEEL,  lg4ff_wheel_effects, 40, 900, lg4ff_set_range_g25},
146 	{USB_DEVICE_ID_LOGITECH_G27_WHEEL,   lg4ff_wheel_effects, 40, 900, lg4ff_set_range_g25},
147 	{USB_DEVICE_ID_LOGITECH_G29_WHEEL,   lg4ff_wheel_effects, 40, 900, lg4ff_set_range_g25},
148 	{USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2, lg4ff_wheel_effects, 40, 270, NULL},
149 	{USB_DEVICE_ID_LOGITECH_WII_WHEEL,   lg4ff_wheel_effects, 40, 270, NULL}
150 };
151 
152 static const struct lg4ff_multimode_wheel lg4ff_multimode_wheels[] = {
153 	{USB_DEVICE_ID_LOGITECH_DFP_WHEEL,
154 	 LG4FF_MODE_NATIVE | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
155 	 LG4FF_DFP_TAG, LG4FF_DFP_NAME},
156 	{USB_DEVICE_ID_LOGITECH_G25_WHEEL,
157 	 LG4FF_MODE_NATIVE | LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
158 	 LG4FF_G25_TAG, LG4FF_G25_NAME},
159 	{USB_DEVICE_ID_LOGITECH_DFGT_WHEEL,
160 	 LG4FF_MODE_NATIVE | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
161 	 LG4FF_DFGT_TAG, LG4FF_DFGT_NAME},
162 	{USB_DEVICE_ID_LOGITECH_G27_WHEEL,
163 	 LG4FF_MODE_NATIVE | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
164 	 LG4FF_G27_TAG, LG4FF_G27_NAME},
165 	{USB_DEVICE_ID_LOGITECH_G29_WHEEL,
166 	 LG4FF_MODE_NATIVE | LG4FF_MODE_G29 | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
167 	 LG4FF_G29_TAG, LG4FF_G29_NAME},
168 };
169 
170 static const struct lg4ff_alternate_mode lg4ff_alternate_modes[] = {
171 	[LG4FF_MODE_NATIVE_IDX] = {0, "native", ""},
172 	[LG4FF_MODE_DFEX_IDX] = {USB_DEVICE_ID_LOGITECH_WHEEL, LG4FF_DFEX_TAG, LG4FF_DFEX_NAME},
173 	[LG4FF_MODE_DFP_IDX] = {USB_DEVICE_ID_LOGITECH_DFP_WHEEL, LG4FF_DFP_TAG, LG4FF_DFP_NAME},
174 	[LG4FF_MODE_G25_IDX] = {USB_DEVICE_ID_LOGITECH_G25_WHEEL, LG4FF_G25_TAG, LG4FF_G25_NAME},
175 	[LG4FF_MODE_DFGT_IDX] = {USB_DEVICE_ID_LOGITECH_DFGT_WHEEL, LG4FF_DFGT_TAG, LG4FF_DFGT_NAME},
176 	[LG4FF_MODE_G27_IDX] = {USB_DEVICE_ID_LOGITECH_G27_WHEEL, LG4FF_G27_TAG, LG4FF_G27_NAME},
177 	[LG4FF_MODE_G29_IDX] = {USB_DEVICE_ID_LOGITECH_G29_WHEEL, LG4FF_G29_TAG, LG4FF_G29_NAME},
178 };
179 
180 /* Multimode wheel identificators */
181 static const struct lg4ff_wheel_ident_info lg4ff_dfp_ident_info = {
182 	LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
183 	0xf000,
184 	0x1000,
185 	USB_DEVICE_ID_LOGITECH_DFP_WHEEL
186 };
187 
188 static const struct lg4ff_wheel_ident_info lg4ff_g25_ident_info = {
189 	LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
190 	0xff00,
191 	0x1200,
192 	USB_DEVICE_ID_LOGITECH_G25_WHEEL
193 };
194 
195 static const struct lg4ff_wheel_ident_info lg4ff_g27_ident_info = {
196 	LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
197 	0xfff0,
198 	0x1230,
199 	USB_DEVICE_ID_LOGITECH_G27_WHEEL
200 };
201 
202 static const struct lg4ff_wheel_ident_info lg4ff_dfgt_ident_info = {
203 	LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
204 	0xff00,
205 	0x1300,
206 	USB_DEVICE_ID_LOGITECH_DFGT_WHEEL
207 };
208 
209 static const struct lg4ff_wheel_ident_info lg4ff_g29_ident_info = {
210 	LG4FF_MODE_G29 | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
211 	0xfff8,
212 	0x1350,
213 	USB_DEVICE_ID_LOGITECH_G29_WHEEL
214 };
215 
216 static const struct lg4ff_wheel_ident_info lg4ff_g29_ident_info2 = {
217 	LG4FF_MODE_G29 | LG4FF_MODE_G27 | LG4FF_MODE_G25 | LG4FF_MODE_DFGT | LG4FF_MODE_DFP | LG4FF_MODE_DFEX,
218 	0xff00,
219 	0x8900,
220 	USB_DEVICE_ID_LOGITECH_G29_WHEEL
221 };
222 
223 /* Multimode wheel identification checklists */
224 static const struct lg4ff_wheel_ident_info *lg4ff_main_checklist[] = {
225 	&lg4ff_g29_ident_info,
226 	&lg4ff_g29_ident_info2,
227 	&lg4ff_dfgt_ident_info,
228 	&lg4ff_g27_ident_info,
229 	&lg4ff_g25_ident_info,
230 	&lg4ff_dfp_ident_info
231 };
232 
233 /* Compatibility mode switching commands */
234 /* EXT_CMD9 - Understood by G27 and DFGT */
235 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfex = {
236 	2,
237 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
238 	 0xf8, 0x09, 0x00, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to DF-EX with detach */
239 };
240 
241 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfp = {
242 	2,
243 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
244 	 0xf8, 0x09, 0x01, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to DFP with detach */
245 };
246 
247 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_g25 = {
248 	2,
249 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
250 	 0xf8, 0x09, 0x02, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to G25 with detach */
251 };
252 
253 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_dfgt = {
254 	2,
255 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
256 	 0xf8, 0x09, 0x03, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to DFGT with detach */
257 };
258 
259 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_g27 = {
260 	2,
261 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
262 	 0xf8, 0x09, 0x04, 0x01, 0x00, 0x00, 0x00}	/* Switch mode to G27 with detach */
263 };
264 
265 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext09_g29 = {
266 	2,
267 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* Revert mode upon USB reset */
268 	 0xf8, 0x09, 0x05, 0x01, 0x01, 0x00, 0x00}	/* Switch mode to G29 with detach */
269 };
270 
271 /* EXT_CMD1 - Understood by DFP, G25, G27 and DFGT */
272 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext01_dfp = {
273 	1,
274 	{0xf8, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00}
275 };
276 
277 /* EXT_CMD16 - Understood by G25 and G27 */
278 static const struct lg4ff_compat_mode_switch lg4ff_mode_switch_ext16_g25 = {
279 	1,
280 	{0xf8, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00}
281 };
282 
283 /* Recalculates X axis value accordingly to currently selected range */
284 static s32 lg4ff_adjust_dfp_x_axis(s32 value, u16 range)
285 {
286 	u16 max_range;
287 	s32 new_value;
288 
289 	if (range == 900)
290 		return value;
291 	else if (range == 200)
292 		return value;
293 	else if (range < 200)
294 		max_range = 200;
295 	else
296 		max_range = 900;
297 
298 	new_value = 8192 + mult_frac(value - 8192, max_range, range);
299 	if (new_value < 0)
300 		return 0;
301 	else if (new_value > 16383)
302 		return 16383;
303 	else
304 		return new_value;
305 }
306 
307 int lg4ff_adjust_input_event(struct hid_device *hid, struct hid_field *field,
308 			     struct hid_usage *usage, s32 value, struct lg_drv_data *drv_data)
309 {
310 	struct lg4ff_device_entry *entry = drv_data->device_props;
311 	s32 new_value = 0;
312 
313 	if (!entry) {
314 		hid_err(hid, "Device properties not found");
315 		return 0;
316 	}
317 
318 	switch (entry->wdata.product_id) {
319 	case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
320 		switch (usage->code) {
321 		case ABS_X:
322 			new_value = lg4ff_adjust_dfp_x_axis(value, entry->wdata.range);
323 			input_event(field->hidinput->input, usage->type, usage->code, new_value);
324 			return 1;
325 		default:
326 			return 0;
327 		}
328 	default:
329 		return 0;
330 	}
331 }
332 
333 static void lg4ff_init_wheel_data(struct lg4ff_wheel_data * const wdata, const struct lg4ff_wheel *wheel,
334 				  const struct lg4ff_multimode_wheel *mmode_wheel,
335 				  const u16 real_product_id)
336 {
337 	u32 alternate_modes = 0;
338 	const char *real_tag = NULL;
339 	const char *real_name = NULL;
340 
341 	if (mmode_wheel) {
342 		alternate_modes = mmode_wheel->alternate_modes;
343 		real_tag = mmode_wheel->real_tag;
344 		real_name = mmode_wheel->real_name;
345 	}
346 
347 	{
348 		struct lg4ff_wheel_data t_wdata =  { .product_id = wheel->product_id,
349 						     .real_product_id = real_product_id,
350 						     .min_range = wheel->min_range,
351 						     .max_range = wheel->max_range,
352 						     .set_range = wheel->set_range,
353 						     .alternate_modes = alternate_modes,
354 						     .real_tag = real_tag,
355 						     .real_name = real_name };
356 
357 		memcpy(wdata, &t_wdata, sizeof(t_wdata));
358 	}
359 }
360 
361 static int lg4ff_play(struct input_dev *dev, void *data, struct ff_effect *effect)
362 {
363 	struct hid_device *hid = input_get_drvdata(dev);
364 	struct lg4ff_device_entry *entry;
365 	struct lg_drv_data *drv_data;
366 	unsigned long flags;
367 	s32 *value;
368 	int x;
369 
370 	drv_data = hid_get_drvdata(hid);
371 	if (!drv_data) {
372 		hid_err(hid, "Private driver data not found!\n");
373 		return -EINVAL;
374 	}
375 
376 	entry = drv_data->device_props;
377 	if (!entry) {
378 		hid_err(hid, "Device properties not found!\n");
379 		return -EINVAL;
380 	}
381 	value = entry->report->field[0]->value;
382 
383 #define CLAMP(x) do { if (x < 0) x = 0; else if (x > 0xff) x = 0xff; } while (0)
384 
385 	switch (effect->type) {
386 	case FF_CONSTANT:
387 		x = effect->u.ramp.start_level + 0x80;	/* 0x80 is no force */
388 		CLAMP(x);
389 
390 		spin_lock_irqsave(&entry->report_lock, flags);
391 		if (x == 0x80) {
392 			/* De-activate force in slot-1*/
393 			value[0] = 0x13;
394 			value[1] = 0x00;
395 			value[2] = 0x00;
396 			value[3] = 0x00;
397 			value[4] = 0x00;
398 			value[5] = 0x00;
399 			value[6] = 0x00;
400 
401 			hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
402 			spin_unlock_irqrestore(&entry->report_lock, flags);
403 			return 0;
404 		}
405 
406 		value[0] = 0x11;	/* Slot 1 */
407 		value[1] = 0x08;
408 		value[2] = x;
409 		value[3] = 0x80;
410 		value[4] = 0x00;
411 		value[5] = 0x00;
412 		value[6] = 0x00;
413 
414 		hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
415 		spin_unlock_irqrestore(&entry->report_lock, flags);
416 		break;
417 	}
418 	return 0;
419 }
420 
421 /* Sends default autocentering command compatible with
422  * all wheels except Formula Force EX */
423 static void lg4ff_set_autocenter_default(struct input_dev *dev, u16 magnitude)
424 {
425 	struct hid_device *hid = input_get_drvdata(dev);
426 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
427 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
428 	s32 *value = report->field[0]->value;
429 	u32 expand_a, expand_b;
430 	struct lg4ff_device_entry *entry;
431 	struct lg_drv_data *drv_data;
432 	unsigned long flags;
433 
434 	drv_data = hid_get_drvdata(hid);
435 	if (!drv_data) {
436 		hid_err(hid, "Private driver data not found!\n");
437 		return;
438 	}
439 
440 	entry = drv_data->device_props;
441 	if (!entry) {
442 		hid_err(hid, "Device properties not found!\n");
443 		return;
444 	}
445 	value = entry->report->field[0]->value;
446 
447 	/* De-activate Auto-Center */
448 	spin_lock_irqsave(&entry->report_lock, flags);
449 	if (magnitude == 0) {
450 		value[0] = 0xf5;
451 		value[1] = 0x00;
452 		value[2] = 0x00;
453 		value[3] = 0x00;
454 		value[4] = 0x00;
455 		value[5] = 0x00;
456 		value[6] = 0x00;
457 
458 		hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
459 		spin_unlock_irqrestore(&entry->report_lock, flags);
460 		return;
461 	}
462 
463 	if (magnitude <= 0xaaaa) {
464 		expand_a = 0x0c * magnitude;
465 		expand_b = 0x80 * magnitude;
466 	} else {
467 		expand_a = (0x0c * 0xaaaa) + 0x06 * (magnitude - 0xaaaa);
468 		expand_b = (0x80 * 0xaaaa) + 0xff * (magnitude - 0xaaaa);
469 	}
470 
471 	/* Adjust for non-MOMO wheels */
472 	switch (entry->wdata.product_id) {
473 	case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL:
474 	case USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2:
475 		break;
476 	default:
477 		expand_a = expand_a >> 1;
478 		break;
479 	}
480 
481 	value[0] = 0xfe;
482 	value[1] = 0x0d;
483 	value[2] = expand_a / 0xaaaa;
484 	value[3] = expand_a / 0xaaaa;
485 	value[4] = expand_b / 0xaaaa;
486 	value[5] = 0x00;
487 	value[6] = 0x00;
488 
489 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
490 
491 	/* Activate Auto-Center */
492 	value[0] = 0x14;
493 	value[1] = 0x00;
494 	value[2] = 0x00;
495 	value[3] = 0x00;
496 	value[4] = 0x00;
497 	value[5] = 0x00;
498 	value[6] = 0x00;
499 
500 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
501 	spin_unlock_irqrestore(&entry->report_lock, flags);
502 }
503 
504 /* Sends autocentering command compatible with Formula Force EX */
505 static void lg4ff_set_autocenter_ffex(struct input_dev *dev, u16 magnitude)
506 {
507 	struct hid_device *hid = input_get_drvdata(dev);
508 	struct lg4ff_device_entry *entry;
509 	struct lg_drv_data *drv_data;
510 	unsigned long flags;
511 	s32 *value;
512 	magnitude = magnitude * 90 / 65535;
513 
514 	drv_data = hid_get_drvdata(hid);
515 	if (!drv_data) {
516 		hid_err(hid, "Private driver data not found!\n");
517 		return;
518 	}
519 
520 	entry = drv_data->device_props;
521 	if (!entry) {
522 		hid_err(hid, "Device properties not found!\n");
523 		return;
524 	}
525 	value = entry->report->field[0]->value;
526 
527 	spin_lock_irqsave(&entry->report_lock, flags);
528 	value[0] = 0xfe;
529 	value[1] = 0x03;
530 	value[2] = magnitude >> 14;
531 	value[3] = magnitude >> 14;
532 	value[4] = magnitude;
533 	value[5] = 0x00;
534 	value[6] = 0x00;
535 
536 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
537 	spin_unlock_irqrestore(&entry->report_lock, flags);
538 }
539 
540 /* Sends command to set range compatible with G25/G27/Driving Force GT */
541 static void lg4ff_set_range_g25(struct hid_device *hid, u16 range)
542 {
543 	struct lg4ff_device_entry *entry;
544 	struct lg_drv_data *drv_data;
545 	unsigned long flags;
546 	s32 *value;
547 
548 	drv_data = hid_get_drvdata(hid);
549 	if (!drv_data) {
550 		hid_err(hid, "Private driver data not found!\n");
551 		return;
552 	}
553 
554 	entry = drv_data->device_props;
555 	if (!entry) {
556 		hid_err(hid, "Device properties not found!\n");
557 		return;
558 	}
559 	value = entry->report->field[0]->value;
560 	dbg_hid("G25/G27/DFGT: setting range to %u\n", range);
561 
562 	spin_lock_irqsave(&entry->report_lock, flags);
563 	value[0] = 0xf8;
564 	value[1] = 0x81;
565 	value[2] = range & 0x00ff;
566 	value[3] = (range & 0xff00) >> 8;
567 	value[4] = 0x00;
568 	value[5] = 0x00;
569 	value[6] = 0x00;
570 
571 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
572 	spin_unlock_irqrestore(&entry->report_lock, flags);
573 }
574 
575 /* Sends commands to set range compatible with Driving Force Pro wheel */
576 static void lg4ff_set_range_dfp(struct hid_device *hid, u16 range)
577 {
578 	struct lg4ff_device_entry *entry;
579 	struct lg_drv_data *drv_data;
580 	unsigned long flags;
581 	int start_left, start_right, full_range;
582 	s32 *value;
583 
584 	drv_data = hid_get_drvdata(hid);
585 	if (!drv_data) {
586 		hid_err(hid, "Private driver data not found!\n");
587 		return;
588 	}
589 
590 	entry = drv_data->device_props;
591 	if (!entry) {
592 		hid_err(hid, "Device properties not found!\n");
593 		return;
594 	}
595 	value = entry->report->field[0]->value;
596 	dbg_hid("Driving Force Pro: setting range to %u\n", range);
597 
598 	/* Prepare "coarse" limit command */
599 	spin_lock_irqsave(&entry->report_lock, flags);
600 	value[0] = 0xf8;
601 	value[1] = 0x00;	/* Set later */
602 	value[2] = 0x00;
603 	value[3] = 0x00;
604 	value[4] = 0x00;
605 	value[5] = 0x00;
606 	value[6] = 0x00;
607 
608 	if (range > 200) {
609 		value[1] = 0x03;
610 		full_range = 900;
611 	} else {
612 		value[1] = 0x02;
613 		full_range = 200;
614 	}
615 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
616 
617 	/* Prepare "fine" limit command */
618 	value[0] = 0x81;
619 	value[1] = 0x0b;
620 	value[2] = 0x00;
621 	value[3] = 0x00;
622 	value[4] = 0x00;
623 	value[5] = 0x00;
624 	value[6] = 0x00;
625 
626 	if (range == 200 || range == 900) {	/* Do not apply any fine limit */
627 		hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
628 		spin_unlock_irqrestore(&entry->report_lock, flags);
629 		return;
630 	}
631 
632 	/* Construct fine limit command */
633 	start_left = (((full_range - range + 1) * 2047) / full_range);
634 	start_right = 0xfff - start_left;
635 
636 	value[2] = start_left >> 4;
637 	value[3] = start_right >> 4;
638 	value[4] = 0xff;
639 	value[5] = (start_right & 0xe) << 4 | (start_left & 0xe);
640 	value[6] = 0xff;
641 
642 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
643 	spin_unlock_irqrestore(&entry->report_lock, flags);
644 }
645 
646 static const struct lg4ff_compat_mode_switch *lg4ff_get_mode_switch_command(const u16 real_product_id, const u16 target_product_id)
647 {
648 	switch (real_product_id) {
649 	case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
650 		switch (target_product_id) {
651 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
652 			return &lg4ff_mode_switch_ext01_dfp;
653 		/* DFP can only be switched to its native mode */
654 		default:
655 			return NULL;
656 		}
657 		break;
658 	case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
659 		switch (target_product_id) {
660 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
661 			return &lg4ff_mode_switch_ext01_dfp;
662 		case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
663 			return &lg4ff_mode_switch_ext16_g25;
664 		/* G25 can only be switched to DFP mode or its native mode */
665 		default:
666 			return NULL;
667 		}
668 		break;
669 	case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
670 		switch (target_product_id) {
671 		case USB_DEVICE_ID_LOGITECH_WHEEL:
672 			return &lg4ff_mode_switch_ext09_dfex;
673 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
674 			return &lg4ff_mode_switch_ext09_dfp;
675 		case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
676 			return &lg4ff_mode_switch_ext09_g25;
677 		case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
678 			return &lg4ff_mode_switch_ext09_g27;
679 		/* G27 can only be switched to DF-EX, DFP, G25 or its native mode */
680 		default:
681 			return NULL;
682 		}
683 		break;
684 	case USB_DEVICE_ID_LOGITECH_G29_WHEEL:
685 		switch (target_product_id) {
686 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
687 			return &lg4ff_mode_switch_ext09_dfp;
688 		case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
689 			return &lg4ff_mode_switch_ext09_dfgt;
690 		case USB_DEVICE_ID_LOGITECH_G25_WHEEL:
691 			return &lg4ff_mode_switch_ext09_g25;
692 		case USB_DEVICE_ID_LOGITECH_G27_WHEEL:
693 			return &lg4ff_mode_switch_ext09_g27;
694 		case USB_DEVICE_ID_LOGITECH_G29_WHEEL:
695 			return &lg4ff_mode_switch_ext09_g29;
696 		/* G29 can only be switched to DF-EX, DFP, DFGT, G25, G27 or its native mode */
697 		default:
698 			return NULL;
699 		}
700 		break;
701 	case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
702 		switch (target_product_id) {
703 		case USB_DEVICE_ID_LOGITECH_WHEEL:
704 			return &lg4ff_mode_switch_ext09_dfex;
705 		case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
706 			return &lg4ff_mode_switch_ext09_dfp;
707 		case USB_DEVICE_ID_LOGITECH_DFGT_WHEEL:
708 			return &lg4ff_mode_switch_ext09_dfgt;
709 		/* DFGT can only be switched to DF-EX, DFP or its native mode */
710 		default:
711 			return NULL;
712 		}
713 		break;
714 	/* No other wheels have multiple modes */
715 	default:
716 		return NULL;
717 	}
718 }
719 
720 static int lg4ff_switch_compatibility_mode(struct hid_device *hid, const struct lg4ff_compat_mode_switch *s)
721 {
722 	struct lg4ff_device_entry *entry;
723 	struct lg_drv_data *drv_data;
724 	unsigned long flags;
725 	s32 *value;
726 	u8 i;
727 
728 	drv_data = hid_get_drvdata(hid);
729 	if (!drv_data) {
730 		hid_err(hid, "Private driver data not found!\n");
731 		return -EINVAL;
732 	}
733 
734 	entry = drv_data->device_props;
735 	if (!entry) {
736 		hid_err(hid, "Device properties not found!\n");
737 		return -EINVAL;
738 	}
739 	value = entry->report->field[0]->value;
740 
741 	spin_lock_irqsave(&entry->report_lock, flags);
742 	for (i = 0; i < s->cmd_count; i++) {
743 		u8 j;
744 
745 		for (j = 0; j < 7; j++)
746 			value[j] = s->cmd[j + (7*i)];
747 
748 		hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
749 	}
750 	spin_unlock_irqrestore(&entry->report_lock, flags);
751 	hid_hw_wait(hid);
752 	return 0;
753 }
754 
755 static ssize_t lg4ff_alternate_modes_show(struct device *dev, struct device_attribute *attr, char *buf)
756 {
757 	struct hid_device *hid = to_hid_device(dev);
758 	struct lg4ff_device_entry *entry;
759 	struct lg_drv_data *drv_data;
760 	ssize_t count = 0;
761 	int i;
762 
763 	drv_data = hid_get_drvdata(hid);
764 	if (!drv_data) {
765 		hid_err(hid, "Private driver data not found!\n");
766 		return 0;
767 	}
768 
769 	entry = drv_data->device_props;
770 	if (!entry) {
771 		hid_err(hid, "Device properties not found!\n");
772 		return 0;
773 	}
774 
775 	if (!entry->wdata.real_name) {
776 		hid_err(hid, "NULL pointer to string\n");
777 		return 0;
778 	}
779 
780 	for (i = 0; i < LG4FF_MODE_MAX_IDX; i++) {
781 		if (entry->wdata.alternate_modes & BIT(i)) {
782 			/* Print tag and full name */
783 			count += scnprintf(buf + count, PAGE_SIZE - count, "%s: %s",
784 					   lg4ff_alternate_modes[i].tag,
785 					   !lg4ff_alternate_modes[i].product_id ? entry->wdata.real_name : lg4ff_alternate_modes[i].name);
786 			if (count >= PAGE_SIZE - 1)
787 				return count;
788 
789 			/* Mark the currently active mode with an asterisk */
790 			if (lg4ff_alternate_modes[i].product_id == entry->wdata.product_id ||
791 			    (lg4ff_alternate_modes[i].product_id == 0 && entry->wdata.product_id == entry->wdata.real_product_id))
792 				count += scnprintf(buf + count, PAGE_SIZE - count, " *\n");
793 			else
794 				count += scnprintf(buf + count, PAGE_SIZE - count, "\n");
795 
796 			if (count >= PAGE_SIZE - 1)
797 				return count;
798 		}
799 	}
800 
801 	return count;
802 }
803 
804 static ssize_t lg4ff_alternate_modes_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
805 {
806 	struct hid_device *hid = to_hid_device(dev);
807 	struct lg4ff_device_entry *entry;
808 	struct lg_drv_data *drv_data;
809 	const struct lg4ff_compat_mode_switch *s;
810 	u16 target_product_id = 0;
811 	int i, ret;
812 	char *lbuf;
813 
814 	drv_data = hid_get_drvdata(hid);
815 	if (!drv_data) {
816 		hid_err(hid, "Private driver data not found!\n");
817 		return -EINVAL;
818 	}
819 
820 	entry = drv_data->device_props;
821 	if (!entry) {
822 		hid_err(hid, "Device properties not found!\n");
823 		return -EINVAL;
824 	}
825 
826 	/* Allow \n at the end of the input parameter */
827 	lbuf = kasprintf(GFP_KERNEL, "%s", buf);
828 	if (!lbuf)
829 		return -ENOMEM;
830 
831 	i = strlen(lbuf);
832 	if (lbuf[i-1] == '\n') {
833 		if (i == 1) {
834 			kfree(lbuf);
835 			return -EINVAL;
836 		}
837 		lbuf[i-1] = '\0';
838 	}
839 
840 	for (i = 0; i < LG4FF_MODE_MAX_IDX; i++) {
841 		const u16 mode_product_id = lg4ff_alternate_modes[i].product_id;
842 		const char *tag = lg4ff_alternate_modes[i].tag;
843 
844 		if (entry->wdata.alternate_modes & BIT(i)) {
845 			if (!strcmp(tag, lbuf)) {
846 				if (!mode_product_id)
847 					target_product_id = entry->wdata.real_product_id;
848 				else
849 					target_product_id = mode_product_id;
850 				break;
851 			}
852 		}
853 	}
854 
855 	if (i == LG4FF_MODE_MAX_IDX) {
856 		hid_info(hid, "Requested mode \"%s\" is not supported by the device\n", lbuf);
857 		kfree(lbuf);
858 		return -EINVAL;
859 	}
860 	kfree(lbuf); /* Not needed anymore */
861 
862 	if (target_product_id == entry->wdata.product_id) /* Nothing to do */
863 		return count;
864 
865 	/* Automatic switching has to be disabled for the switch to DF-EX mode to work correctly */
866 	if (target_product_id == USB_DEVICE_ID_LOGITECH_WHEEL && !lg4ff_no_autoswitch) {
867 		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",
868 			 entry->wdata.real_name);
869 		return -EINVAL;
870 	}
871 
872 	/* Take care of hardware limitations */
873 	if ((entry->wdata.real_product_id == USB_DEVICE_ID_LOGITECH_DFP_WHEEL || entry->wdata.real_product_id == USB_DEVICE_ID_LOGITECH_G25_WHEEL) &&
874 	    entry->wdata.product_id > target_product_id) {
875 		hid_info(hid, "\"%s\" cannot be switched back into \"%s\" mode\n", entry->wdata.real_name, lg4ff_alternate_modes[i].name);
876 		return -EINVAL;
877 	}
878 
879 	s = lg4ff_get_mode_switch_command(entry->wdata.real_product_id, target_product_id);
880 	if (!s) {
881 		hid_err(hid, "Invalid target product ID %X\n", target_product_id);
882 		return -EINVAL;
883 	}
884 
885 	ret = lg4ff_switch_compatibility_mode(hid, s);
886 	return (ret == 0 ? count : ret);
887 }
888 static DEVICE_ATTR(alternate_modes, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH, lg4ff_alternate_modes_show, lg4ff_alternate_modes_store);
889 
890 /* Export the currently set range of the wheel */
891 static ssize_t lg4ff_range_show(struct device *dev, struct device_attribute *attr,
892 				char *buf)
893 {
894 	struct hid_device *hid = to_hid_device(dev);
895 	struct lg4ff_device_entry *entry;
896 	struct lg_drv_data *drv_data;
897 	size_t count;
898 
899 	drv_data = hid_get_drvdata(hid);
900 	if (!drv_data) {
901 		hid_err(hid, "Private driver data not found!\n");
902 		return 0;
903 	}
904 
905 	entry = drv_data->device_props;
906 	if (!entry) {
907 		hid_err(hid, "Device properties not found!\n");
908 		return 0;
909 	}
910 
911 	count = scnprintf(buf, PAGE_SIZE, "%u\n", entry->wdata.range);
912 	return count;
913 }
914 
915 /* Set range to user specified value, call appropriate function
916  * according to the type of the wheel */
917 static ssize_t lg4ff_range_store(struct device *dev, struct device_attribute *attr,
918 				 const char *buf, size_t count)
919 {
920 	struct hid_device *hid = to_hid_device(dev);
921 	struct lg4ff_device_entry *entry;
922 	struct lg_drv_data *drv_data;
923 	u16 range = simple_strtoul(buf, NULL, 10);
924 
925 	drv_data = hid_get_drvdata(hid);
926 	if (!drv_data) {
927 		hid_err(hid, "Private driver data not found!\n");
928 		return -EINVAL;
929 	}
930 
931 	entry = drv_data->device_props;
932 	if (!entry) {
933 		hid_err(hid, "Device properties not found!\n");
934 		return -EINVAL;
935 	}
936 
937 	if (range == 0)
938 		range = entry->wdata.max_range;
939 
940 	/* Check if the wheel supports range setting
941 	 * and that the range is within limits for the wheel */
942 	if (entry->wdata.set_range && range >= entry->wdata.min_range && range <= entry->wdata.max_range) {
943 		entry->wdata.set_range(hid, range);
944 		entry->wdata.range = range;
945 	}
946 
947 	return count;
948 }
949 static DEVICE_ATTR(range, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH, lg4ff_range_show, lg4ff_range_store);
950 
951 static ssize_t lg4ff_real_id_show(struct device *dev, struct device_attribute *attr, char *buf)
952 {
953 	struct hid_device *hid = to_hid_device(dev);
954 	struct lg4ff_device_entry *entry;
955 	struct lg_drv_data *drv_data;
956 	size_t count;
957 
958 	drv_data = hid_get_drvdata(hid);
959 	if (!drv_data) {
960 		hid_err(hid, "Private driver data not found!\n");
961 		return 0;
962 	}
963 
964 	entry = drv_data->device_props;
965 	if (!entry) {
966 		hid_err(hid, "Device properties not found!\n");
967 		return 0;
968 	}
969 
970 	if (!entry->wdata.real_tag || !entry->wdata.real_name) {
971 		hid_err(hid, "NULL pointer to string\n");
972 		return 0;
973 	}
974 
975 	count = scnprintf(buf, PAGE_SIZE, "%s: %s\n", entry->wdata.real_tag, entry->wdata.real_name);
976 	return count;
977 }
978 
979 static ssize_t lg4ff_real_id_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
980 {
981 	/* Real ID is a read-only value */
982 	return -EPERM;
983 }
984 static DEVICE_ATTR(real_id, S_IRUGO, lg4ff_real_id_show, lg4ff_real_id_store);
985 
986 #ifdef CONFIG_LEDS_CLASS
987 static void lg4ff_set_leds(struct hid_device *hid, u8 leds)
988 {
989 	struct lg_drv_data *drv_data;
990 	struct lg4ff_device_entry *entry;
991 	unsigned long flags;
992 	s32 *value;
993 
994 	drv_data = hid_get_drvdata(hid);
995 	if (!drv_data) {
996 		hid_err(hid, "Private driver data not found!\n");
997 		return;
998 	}
999 
1000 	entry = drv_data->device_props;
1001 	if (!entry) {
1002 		hid_err(hid, "Device properties not found!\n");
1003 		return;
1004 	}
1005 	value = entry->report->field[0]->value;
1006 
1007 	spin_lock_irqsave(&entry->report_lock, flags);
1008 	value[0] = 0xf8;
1009 	value[1] = 0x12;
1010 	value[2] = leds;
1011 	value[3] = 0x00;
1012 	value[4] = 0x00;
1013 	value[5] = 0x00;
1014 	value[6] = 0x00;
1015 	hid_hw_request(hid, entry->report, HID_REQ_SET_REPORT);
1016 	spin_unlock_irqrestore(&entry->report_lock, flags);
1017 }
1018 
1019 static void lg4ff_led_set_brightness(struct led_classdev *led_cdev,
1020 			enum led_brightness value)
1021 {
1022 	struct device *dev = led_cdev->dev->parent;
1023 	struct hid_device *hid = container_of(dev, struct hid_device, dev);
1024 	struct lg_drv_data *drv_data = hid_get_drvdata(hid);
1025 	struct lg4ff_device_entry *entry;
1026 	int i, state = 0;
1027 
1028 	if (!drv_data) {
1029 		hid_err(hid, "Device data not found.");
1030 		return;
1031 	}
1032 
1033 	entry = drv_data->device_props;
1034 
1035 	if (!entry) {
1036 		hid_err(hid, "Device properties not found.");
1037 		return;
1038 	}
1039 
1040 	for (i = 0; i < 5; i++) {
1041 		if (led_cdev != entry->wdata.led[i])
1042 			continue;
1043 		state = (entry->wdata.led_state >> i) & 1;
1044 		if (value == LED_OFF && state) {
1045 			entry->wdata.led_state &= ~(1 << i);
1046 			lg4ff_set_leds(hid, entry->wdata.led_state);
1047 		} else if (value != LED_OFF && !state) {
1048 			entry->wdata.led_state |= 1 << i;
1049 			lg4ff_set_leds(hid, entry->wdata.led_state);
1050 		}
1051 		break;
1052 	}
1053 }
1054 
1055 static enum led_brightness lg4ff_led_get_brightness(struct led_classdev *led_cdev)
1056 {
1057 	struct device *dev = led_cdev->dev->parent;
1058 	struct hid_device *hid = container_of(dev, struct hid_device, dev);
1059 	struct lg_drv_data *drv_data = hid_get_drvdata(hid);
1060 	struct lg4ff_device_entry *entry;
1061 	int i, value = 0;
1062 
1063 	if (!drv_data) {
1064 		hid_err(hid, "Device data not found.");
1065 		return LED_OFF;
1066 	}
1067 
1068 	entry = drv_data->device_props;
1069 
1070 	if (!entry) {
1071 		hid_err(hid, "Device properties not found.");
1072 		return LED_OFF;
1073 	}
1074 
1075 	for (i = 0; i < 5; i++)
1076 		if (led_cdev == entry->wdata.led[i]) {
1077 			value = (entry->wdata.led_state >> i) & 1;
1078 			break;
1079 		}
1080 
1081 	return value ? LED_FULL : LED_OFF;
1082 }
1083 #endif
1084 
1085 static u16 lg4ff_identify_multimode_wheel(struct hid_device *hid, const u16 reported_product_id, const u16 bcdDevice)
1086 {
1087 	u32 current_mode;
1088 	int i;
1089 
1090 	/* identify current mode from USB PID */
1091 	for (i = 1; i < ARRAY_SIZE(lg4ff_alternate_modes); i++) {
1092 		dbg_hid("Testing whether PID is %X\n", lg4ff_alternate_modes[i].product_id);
1093 		if (reported_product_id == lg4ff_alternate_modes[i].product_id)
1094 			break;
1095 	}
1096 
1097 	if (i == ARRAY_SIZE(lg4ff_alternate_modes))
1098 		return 0;
1099 
1100 	current_mode = BIT(i);
1101 
1102 	for (i = 0; i < ARRAY_SIZE(lg4ff_main_checklist); i++) {
1103 		const u16 mask = lg4ff_main_checklist[i]->mask;
1104 		const u16 result = lg4ff_main_checklist[i]->result;
1105 		const u16 real_product_id = lg4ff_main_checklist[i]->real_product_id;
1106 
1107 		if ((current_mode & lg4ff_main_checklist[i]->modes) && \
1108 				(bcdDevice & mask) == result) {
1109 			dbg_hid("Found wheel with real PID %X whose reported PID is %X\n", real_product_id, reported_product_id);
1110 			return real_product_id;
1111 		}
1112 	}
1113 
1114 	/* No match found. This is either Driving Force or an unknown
1115 	 * wheel model, do not touch it */
1116 	dbg_hid("Wheel with bcdDevice %X was not recognized as multimode wheel, leaving in its current mode\n", bcdDevice);
1117 	return 0;
1118 }
1119 
1120 static int lg4ff_handle_multimode_wheel(struct hid_device *hid, u16 *real_product_id, const u16 bcdDevice)
1121 {
1122 	const u16 reported_product_id = hid->product;
1123 	int ret;
1124 
1125 	*real_product_id = lg4ff_identify_multimode_wheel(hid, reported_product_id, bcdDevice);
1126 	/* Probed wheel is not a multimode wheel */
1127 	if (!*real_product_id) {
1128 		*real_product_id = reported_product_id;
1129 		dbg_hid("Wheel is not a multimode wheel\n");
1130 		return LG4FF_MMODE_NOT_MULTIMODE;
1131 	}
1132 
1133 	/* Switch from "Driving Force" mode to native mode automatically.
1134 	 * Otherwise keep the wheel in its current mode */
1135 	if (reported_product_id == USB_DEVICE_ID_LOGITECH_WHEEL &&
1136 	    reported_product_id != *real_product_id &&
1137 	    !lg4ff_no_autoswitch) {
1138 		const struct lg4ff_compat_mode_switch *s = lg4ff_get_mode_switch_command(*real_product_id, *real_product_id);
1139 
1140 		if (!s) {
1141 			hid_err(hid, "Invalid product id %X\n", *real_product_id);
1142 			return LG4FF_MMODE_NOT_MULTIMODE;
1143 		}
1144 
1145 		ret = lg4ff_switch_compatibility_mode(hid, s);
1146 		if (ret) {
1147 			/* Wheel could not have been switched to native mode,
1148 			 * leave it in "Driving Force" mode and continue */
1149 			hid_err(hid, "Unable to switch wheel mode, errno %d\n", ret);
1150 			return LG4FF_MMODE_IS_MULTIMODE;
1151 		}
1152 		return LG4FF_MMODE_SWITCHED;
1153 	}
1154 
1155 	return LG4FF_MMODE_IS_MULTIMODE;
1156 }
1157 
1158 
1159 int lg4ff_init(struct hid_device *hid)
1160 {
1161 	struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
1162 	struct input_dev *dev = hidinput->input;
1163 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
1164 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
1165 	const struct usb_device_descriptor *udesc = &(hid_to_usb_dev(hid)->descriptor);
1166 	const u16 bcdDevice = le16_to_cpu(udesc->bcdDevice);
1167 	const struct lg4ff_multimode_wheel *mmode_wheel = NULL;
1168 	struct lg4ff_device_entry *entry;
1169 	struct lg_drv_data *drv_data;
1170 	int error, i, j;
1171 	int mmode_ret, mmode_idx = -1;
1172 	u16 real_product_id;
1173 
1174 	/* Check that the report looks ok */
1175 	if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
1176 		return -1;
1177 
1178 	drv_data = hid_get_drvdata(hid);
1179 	if (!drv_data) {
1180 		hid_err(hid, "Cannot add device, private driver data not allocated\n");
1181 		return -1;
1182 	}
1183 	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
1184 	if (!entry)
1185 		return -ENOMEM;
1186 	spin_lock_init(&entry->report_lock);
1187 	entry->report = report;
1188 	drv_data->device_props = entry;
1189 
1190 	/* Check if a multimode wheel has been connected and
1191 	 * handle it appropriately */
1192 	mmode_ret = lg4ff_handle_multimode_wheel(hid, &real_product_id, bcdDevice);
1193 
1194 	/* Wheel has been told to switch to native mode. There is no point in going on
1195 	 * with the initialization as the wheel will do a USB reset when it switches mode
1196 	 */
1197 	if (mmode_ret == LG4FF_MMODE_SWITCHED)
1198 		return 0;
1199 	else if (mmode_ret < 0) {
1200 		hid_err(hid, "Unable to switch device mode during initialization, errno %d\n", mmode_ret);
1201 		error = mmode_ret;
1202 		goto err_init;
1203 	}
1204 
1205 	/* Check what wheel has been connected */
1206 	for (i = 0; i < ARRAY_SIZE(lg4ff_devices); i++) {
1207 		if (hid->product == lg4ff_devices[i].product_id) {
1208 			dbg_hid("Found compatible device, product ID %04X\n", lg4ff_devices[i].product_id);
1209 			break;
1210 		}
1211 	}
1212 
1213 	if (i == ARRAY_SIZE(lg4ff_devices)) {
1214 		hid_err(hid, "This device is flagged to be handled by the lg4ff module but this module does not know how to handle it. "
1215 			     "Please report this as a bug to LKML, Simon Wood <simon@mungewell.org> or "
1216 			     "Michal Maly <madcatxster@devoid-pointer.net>\n");
1217 		error = -1;
1218 		goto err_init;
1219 	}
1220 
1221 	if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
1222 		for (mmode_idx = 0; mmode_idx < ARRAY_SIZE(lg4ff_multimode_wheels); mmode_idx++) {
1223 			if (real_product_id == lg4ff_multimode_wheels[mmode_idx].product_id)
1224 				break;
1225 		}
1226 
1227 		if (mmode_idx == ARRAY_SIZE(lg4ff_multimode_wheels)) {
1228 			hid_err(hid, "Device product ID %X is not listed as a multimode wheel", real_product_id);
1229 			error = -1;
1230 			goto err_init;
1231 		}
1232 	}
1233 
1234 	/* Set supported force feedback capabilities */
1235 	for (j = 0; lg4ff_devices[i].ff_effects[j] >= 0; j++)
1236 		set_bit(lg4ff_devices[i].ff_effects[j], dev->ffbit);
1237 
1238 	error = input_ff_create_memless(dev, NULL, lg4ff_play);
1239 
1240 	if (error)
1241 		goto err_init;
1242 
1243 	/* Initialize device properties */
1244 	if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
1245 		BUG_ON(mmode_idx == -1);
1246 		mmode_wheel = &lg4ff_multimode_wheels[mmode_idx];
1247 	}
1248 	lg4ff_init_wheel_data(&entry->wdata, &lg4ff_devices[i], mmode_wheel, real_product_id);
1249 
1250 	/* Check if autocentering is available and
1251 	 * set the centering force to zero by default */
1252 	if (test_bit(FF_AUTOCENTER, dev->ffbit)) {
1253 		/* Formula Force EX expects different autocentering command */
1254 		if ((bcdDevice >> 8) == LG4FF_FFEX_REV_MAJ &&
1255 		    (bcdDevice & 0xff) == LG4FF_FFEX_REV_MIN)
1256 			dev->ff->set_autocenter = lg4ff_set_autocenter_ffex;
1257 		else
1258 			dev->ff->set_autocenter = lg4ff_set_autocenter_default;
1259 
1260 		dev->ff->set_autocenter(dev, 0);
1261 	}
1262 
1263 	/* Create sysfs interface */
1264 	error = device_create_file(&hid->dev, &dev_attr_range);
1265 	if (error)
1266 		hid_warn(hid, "Unable to create sysfs interface for \"range\", errno %d\n", error);
1267 	if (mmode_ret == LG4FF_MMODE_IS_MULTIMODE) {
1268 		error = device_create_file(&hid->dev, &dev_attr_real_id);
1269 		if (error)
1270 			hid_warn(hid, "Unable to create sysfs interface for \"real_id\", errno %d\n", error);
1271 		error = device_create_file(&hid->dev, &dev_attr_alternate_modes);
1272 		if (error)
1273 			hid_warn(hid, "Unable to create sysfs interface for \"alternate_modes\", errno %d\n", error);
1274 	}
1275 	dbg_hid("sysfs interface created\n");
1276 
1277 	/* Set the maximum range to start with */
1278 	entry->wdata.range = entry->wdata.max_range;
1279 	if (entry->wdata.set_range)
1280 		entry->wdata.set_range(hid, entry->wdata.range);
1281 
1282 #ifdef CONFIG_LEDS_CLASS
1283 	/* register led subsystem - G27/G29 only */
1284 	entry->wdata.led_state = 0;
1285 	for (j = 0; j < 5; j++)
1286 		entry->wdata.led[j] = NULL;
1287 
1288 	if (lg4ff_devices[i].product_id == USB_DEVICE_ID_LOGITECH_G27_WHEEL ||
1289 			lg4ff_devices[i].product_id == USB_DEVICE_ID_LOGITECH_G29_WHEEL) {
1290 		struct led_classdev *led;
1291 		size_t name_sz;
1292 		char *name;
1293 
1294 		lg4ff_set_leds(hid, 0);
1295 
1296 		name_sz = strlen(dev_name(&hid->dev)) + 8;
1297 
1298 		for (j = 0; j < 5; j++) {
1299 			led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
1300 			if (!led) {
1301 				hid_err(hid, "can't allocate memory for LED %d\n", j);
1302 				goto err_leds;
1303 			}
1304 
1305 			name = (void *)(&led[1]);
1306 			snprintf(name, name_sz, "%s::RPM%d", dev_name(&hid->dev), j+1);
1307 			led->name = name;
1308 			led->brightness = 0;
1309 			led->max_brightness = 1;
1310 			led->brightness_get = lg4ff_led_get_brightness;
1311 			led->brightness_set = lg4ff_led_set_brightness;
1312 
1313 			entry->wdata.led[j] = led;
1314 			error = led_classdev_register(&hid->dev, led);
1315 
1316 			if (error) {
1317 				hid_err(hid, "failed to register LED %d. Aborting.\n", j);
1318 err_leds:
1319 				/* Deregister LEDs (if any) */
1320 				for (j = 0; j < 5; j++) {
1321 					led = entry->wdata.led[j];
1322 					entry->wdata.led[j] = NULL;
1323 					if (!led)
1324 						continue;
1325 					led_classdev_unregister(led);
1326 					kfree(led);
1327 				}
1328 				goto out;	/* Let the driver continue without LEDs */
1329 			}
1330 		}
1331 	}
1332 out:
1333 #endif
1334 	hid_info(hid, "Force feedback support for Logitech Gaming Wheels\n");
1335 	return 0;
1336 
1337 err_init:
1338 	drv_data->device_props = NULL;
1339 	kfree(entry);
1340 	return error;
1341 }
1342 
1343 int lg4ff_deinit(struct hid_device *hid)
1344 {
1345 	struct lg4ff_device_entry *entry;
1346 	struct lg_drv_data *drv_data;
1347 
1348 	drv_data = hid_get_drvdata(hid);
1349 	if (!drv_data) {
1350 		hid_err(hid, "Error while deinitializing device, no private driver data.\n");
1351 		return -1;
1352 	}
1353 	entry = drv_data->device_props;
1354 	if (!entry)
1355 		goto out; /* Nothing more to do */
1356 
1357 	/* Multimode devices will have at least the "MODE_NATIVE" bit set */
1358 	if (entry->wdata.alternate_modes) {
1359 		device_remove_file(&hid->dev, &dev_attr_real_id);
1360 		device_remove_file(&hid->dev, &dev_attr_alternate_modes);
1361 	}
1362 
1363 	device_remove_file(&hid->dev, &dev_attr_range);
1364 #ifdef CONFIG_LEDS_CLASS
1365 	{
1366 		int j;
1367 		struct led_classdev *led;
1368 
1369 		/* Deregister LEDs (if any) */
1370 		for (j = 0; j < 5; j++) {
1371 
1372 			led = entry->wdata.led[j];
1373 			entry->wdata.led[j] = NULL;
1374 			if (!led)
1375 				continue;
1376 			led_classdev_unregister(led);
1377 			kfree(led);
1378 		}
1379 	}
1380 #endif
1381 	hid_hw_stop(hid);
1382 	drv_data->device_props = NULL;
1383 
1384 	kfree(entry);
1385 out:
1386 	dbg_hid("Device successfully unregistered\n");
1387 	return 0;
1388 }
1389