xref: /openbmc/linux/drivers/hid/hid-lg4ff.c (revision e23feb16)
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-ids.h"
34 
35 #define DFGT_REV_MAJ 0x13
36 #define DFGT_REV_MIN 0x22
37 #define DFGT2_REV_MIN 0x26
38 #define DFP_REV_MAJ 0x11
39 #define DFP_REV_MIN 0x06
40 #define FFEX_REV_MAJ 0x21
41 #define FFEX_REV_MIN 0x00
42 #define G25_REV_MAJ 0x12
43 #define G25_REV_MIN 0x22
44 #define G27_REV_MAJ 0x12
45 #define G27_REV_MIN 0x38
46 
47 #define to_hid_device(pdev) container_of(pdev, struct hid_device, dev)
48 
49 static void hid_lg4ff_set_range_dfp(struct hid_device *hid, u16 range);
50 static void hid_lg4ff_set_range_g25(struct hid_device *hid, u16 range);
51 static ssize_t lg4ff_range_show(struct device *dev, struct device_attribute *attr, char *buf);
52 static ssize_t lg4ff_range_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count);
53 
54 static DEVICE_ATTR(range, S_IRWXU | S_IRWXG | S_IRWXO, lg4ff_range_show, lg4ff_range_store);
55 
56 struct lg4ff_device_entry {
57 	__u32 product_id;
58 	__u16 range;
59 	__u16 min_range;
60 	__u16 max_range;
61 #ifdef CONFIG_LEDS_CLASS
62 	__u8  led_state;
63 	struct led_classdev *led[5];
64 #endif
65 	struct list_head list;
66 	void (*set_range)(struct hid_device *hid, u16 range);
67 };
68 
69 static const signed short lg4ff_wheel_effects[] = {
70 	FF_CONSTANT,
71 	FF_AUTOCENTER,
72 	-1
73 };
74 
75 struct lg4ff_wheel {
76 	const __u32 product_id;
77 	const signed short *ff_effects;
78 	const __u16 min_range;
79 	const __u16 max_range;
80 	void (*set_range)(struct hid_device *hid, u16 range);
81 };
82 
83 static const struct lg4ff_wheel lg4ff_devices[] = {
84 	{USB_DEVICE_ID_LOGITECH_WHEEL,       lg4ff_wheel_effects, 40, 270, NULL},
85 	{USB_DEVICE_ID_LOGITECH_MOMO_WHEEL,  lg4ff_wheel_effects, 40, 270, NULL},
86 	{USB_DEVICE_ID_LOGITECH_DFP_WHEEL,   lg4ff_wheel_effects, 40, 900, hid_lg4ff_set_range_dfp},
87 	{USB_DEVICE_ID_LOGITECH_G25_WHEEL,   lg4ff_wheel_effects, 40, 900, hid_lg4ff_set_range_g25},
88 	{USB_DEVICE_ID_LOGITECH_DFGT_WHEEL,  lg4ff_wheel_effects, 40, 900, hid_lg4ff_set_range_g25},
89 	{USB_DEVICE_ID_LOGITECH_G27_WHEEL,   lg4ff_wheel_effects, 40, 900, hid_lg4ff_set_range_g25},
90 	{USB_DEVICE_ID_LOGITECH_MOMO_WHEEL2, lg4ff_wheel_effects, 40, 270, NULL},
91 	{USB_DEVICE_ID_LOGITECH_WII_WHEEL,   lg4ff_wheel_effects, 40, 270, NULL}
92 };
93 
94 struct lg4ff_native_cmd {
95 	const __u8 cmd_num;	/* Number of commands to send */
96 	const __u8 cmd[];
97 };
98 
99 struct lg4ff_usb_revision {
100 	const __u16 rev_maj;
101 	const __u16 rev_min;
102 	const struct lg4ff_native_cmd *command;
103 };
104 
105 static const struct lg4ff_native_cmd native_dfp = {
106 	1,
107 	{0xf8, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00}
108 };
109 
110 static const struct lg4ff_native_cmd native_dfgt = {
111 	2,
112 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* 1st command */
113 	 0xf8, 0x09, 0x03, 0x01, 0x00, 0x00, 0x00}	/* 2nd command */
114 };
115 
116 static const struct lg4ff_native_cmd native_g25 = {
117 	1,
118 	{0xf8, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00}
119 };
120 
121 static const struct lg4ff_native_cmd native_g27 = {
122 	2,
123 	{0xf8, 0x0a, 0x00, 0x00, 0x00, 0x00, 0x00,	/* 1st command */
124 	 0xf8, 0x09, 0x04, 0x01, 0x00, 0x00, 0x00}	/* 2nd command */
125 };
126 
127 static const struct lg4ff_usb_revision lg4ff_revs[] = {
128 	{DFGT_REV_MAJ, DFGT_REV_MIN, &native_dfgt},	/* Driving Force GT */
129 	{DFGT_REV_MAJ, DFGT2_REV_MIN, &native_dfgt},	/* Driving Force GT v2 */
130 	{DFP_REV_MAJ,  DFP_REV_MIN,  &native_dfp},	/* Driving Force Pro */
131 	{G25_REV_MAJ,  G25_REV_MIN,  &native_g25},	/* G25 */
132 	{G27_REV_MAJ,  G27_REV_MIN,  &native_g27},	/* G27 */
133 };
134 
135 /* Recalculates X axis value accordingly to currently selected range */
136 static __s32 lg4ff_adjust_dfp_x_axis(__s32 value, __u16 range)
137 {
138 	__u16 max_range;
139 	__s32 new_value;
140 
141 	if (range == 900)
142 		return value;
143 	else if (range == 200)
144 		return value;
145 	else if (range < 200)
146 		max_range = 200;
147 	else
148 		max_range = 900;
149 
150 	new_value = 8192 + mult_frac(value - 8192, max_range, range);
151 	if (new_value < 0)
152 		return 0;
153 	else if (new_value > 16383)
154 		return 16383;
155 	else
156 		return new_value;
157 }
158 
159 int lg4ff_adjust_input_event(struct hid_device *hid, struct hid_field *field,
160 			     struct hid_usage *usage, __s32 value, struct lg_drv_data *drv_data)
161 {
162 	struct lg4ff_device_entry *entry = drv_data->device_props;
163 	__s32 new_value = 0;
164 
165 	if (!entry) {
166 		hid_err(hid, "Device properties not found");
167 		return 0;
168 	}
169 
170 	switch (entry->product_id) {
171 	case USB_DEVICE_ID_LOGITECH_DFP_WHEEL:
172 		switch (usage->code) {
173 		case ABS_X:
174 			new_value = lg4ff_adjust_dfp_x_axis(value, entry->range);
175 			input_event(field->hidinput->input, usage->type, usage->code, new_value);
176 			return 1;
177 		default:
178 			return 0;
179 		}
180 	default:
181 		return 0;
182 	}
183 }
184 
185 static int hid_lg4ff_play(struct input_dev *dev, void *data, struct ff_effect *effect)
186 {
187 	struct hid_device *hid = input_get_drvdata(dev);
188 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
189 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
190 	__s32 *value = report->field[0]->value;
191 	int x;
192 
193 #define CLAMP(x) do { if (x < 0) x = 0; else if (x > 0xff) x = 0xff; } while (0)
194 
195 	switch (effect->type) {
196 	case FF_CONSTANT:
197 		x = effect->u.ramp.start_level + 0x80;	/* 0x80 is no force */
198 		CLAMP(x);
199 		value[0] = 0x11;	/* Slot 1 */
200 		value[1] = 0x08;
201 		value[2] = x;
202 		value[3] = 0x80;
203 		value[4] = 0x00;
204 		value[5] = 0x00;
205 		value[6] = 0x00;
206 
207 		hid_hw_request(hid, report, HID_REQ_SET_REPORT);
208 		break;
209 	}
210 	return 0;
211 }
212 
213 /* Sends default autocentering command compatible with
214  * all wheels except Formula Force EX */
215 static void hid_lg4ff_set_autocenter_default(struct input_dev *dev, u16 magnitude)
216 {
217 	struct hid_device *hid = input_get_drvdata(dev);
218 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
219 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
220 	__s32 *value = report->field[0]->value;
221 
222 	value[0] = 0xfe;
223 	value[1] = 0x0d;
224 	value[2] = magnitude >> 13;
225 	value[3] = magnitude >> 13;
226 	value[4] = magnitude >> 8;
227 	value[5] = 0x00;
228 	value[6] = 0x00;
229 
230 	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
231 }
232 
233 /* Sends autocentering command compatible with Formula Force EX */
234 static void hid_lg4ff_set_autocenter_ffex(struct input_dev *dev, u16 magnitude)
235 {
236 	struct hid_device *hid = input_get_drvdata(dev);
237 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
238 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
239 	__s32 *value = report->field[0]->value;
240 	magnitude = magnitude * 90 / 65535;
241 
242 	value[0] = 0xfe;
243 	value[1] = 0x03;
244 	value[2] = magnitude >> 14;
245 	value[3] = magnitude >> 14;
246 	value[4] = magnitude;
247 	value[5] = 0x00;
248 	value[6] = 0x00;
249 
250 	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
251 }
252 
253 /* Sends command to set range compatible with G25/G27/Driving Force GT */
254 static void hid_lg4ff_set_range_g25(struct hid_device *hid, u16 range)
255 {
256 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
257 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
258 	__s32 *value = report->field[0]->value;
259 
260 	dbg_hid("G25/G27/DFGT: setting range to %u\n", range);
261 
262 	value[0] = 0xf8;
263 	value[1] = 0x81;
264 	value[2] = range & 0x00ff;
265 	value[3] = (range & 0xff00) >> 8;
266 	value[4] = 0x00;
267 	value[5] = 0x00;
268 	value[6] = 0x00;
269 
270 	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
271 }
272 
273 /* Sends commands to set range compatible with Driving Force Pro wheel */
274 static void hid_lg4ff_set_range_dfp(struct hid_device *hid, __u16 range)
275 {
276 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
277 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
278 	int start_left, start_right, full_range;
279 	__s32 *value = report->field[0]->value;
280 
281 	dbg_hid("Driving Force Pro: setting range to %u\n", range);
282 
283 	/* Prepare "coarse" limit command */
284 	value[0] = 0xf8;
285 	value[1] = 0x00;	/* Set later */
286 	value[2] = 0x00;
287 	value[3] = 0x00;
288 	value[4] = 0x00;
289 	value[5] = 0x00;
290 	value[6] = 0x00;
291 
292 	if (range > 200) {
293 		report->field[0]->value[1] = 0x03;
294 		full_range = 900;
295 	} else {
296 		report->field[0]->value[1] = 0x02;
297 		full_range = 200;
298 	}
299 	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
300 
301 	/* Prepare "fine" limit command */
302 	value[0] = 0x81;
303 	value[1] = 0x0b;
304 	value[2] = 0x00;
305 	value[3] = 0x00;
306 	value[4] = 0x00;
307 	value[5] = 0x00;
308 	value[6] = 0x00;
309 
310 	if (range == 200 || range == 900) {	/* Do not apply any fine limit */
311 		hid_hw_request(hid, report, HID_REQ_SET_REPORT);
312 		return;
313 	}
314 
315 	/* Construct fine limit command */
316 	start_left = (((full_range - range + 1) * 2047) / full_range);
317 	start_right = 0xfff - start_left;
318 
319 	value[2] = start_left >> 4;
320 	value[3] = start_right >> 4;
321 	value[4] = 0xff;
322 	value[5] = (start_right & 0xe) << 4 | (start_left & 0xe);
323 	value[6] = 0xff;
324 
325 	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
326 }
327 
328 static void hid_lg4ff_switch_native(struct hid_device *hid, const struct lg4ff_native_cmd *cmd)
329 {
330 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
331 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
332 	__u8 i, j;
333 
334 	j = 0;
335 	while (j < 7*cmd->cmd_num) {
336 		for (i = 0; i < 7; i++)
337 			report->field[0]->value[i] = cmd->cmd[j++];
338 
339 		hid_hw_request(hid, report, HID_REQ_SET_REPORT);
340 	}
341 }
342 
343 /* Read current range and display it in terminal */
344 static ssize_t lg4ff_range_show(struct device *dev, struct device_attribute *attr, char *buf)
345 {
346 	struct hid_device *hid = to_hid_device(dev);
347 	struct lg4ff_device_entry *entry;
348 	struct lg_drv_data *drv_data;
349 	size_t count;
350 
351 	drv_data = hid_get_drvdata(hid);
352 	if (!drv_data) {
353 		hid_err(hid, "Private driver data not found!\n");
354 		return 0;
355 	}
356 
357 	entry = drv_data->device_props;
358 	if (!entry) {
359 		hid_err(hid, "Device properties not found!\n");
360 		return 0;
361 	}
362 
363 	count = scnprintf(buf, PAGE_SIZE, "%u\n", entry->range);
364 	return count;
365 }
366 
367 /* Set range to user specified value, call appropriate function
368  * according to the type of the wheel */
369 static ssize_t lg4ff_range_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
370 {
371 	struct hid_device *hid = to_hid_device(dev);
372 	struct lg4ff_device_entry *entry;
373 	struct lg_drv_data *drv_data;
374 	__u16 range = simple_strtoul(buf, NULL, 10);
375 
376 	drv_data = hid_get_drvdata(hid);
377 	if (!drv_data) {
378 		hid_err(hid, "Private driver data not found!\n");
379 		return 0;
380 	}
381 
382 	entry = drv_data->device_props;
383 	if (!entry) {
384 		hid_err(hid, "Device properties not found!\n");
385 		return 0;
386 	}
387 
388 	if (range == 0)
389 		range = entry->max_range;
390 
391 	/* Check if the wheel supports range setting
392 	 * and that the range is within limits for the wheel */
393 	if (entry->set_range != NULL && range >= entry->min_range && range <= entry->max_range) {
394 		entry->set_range(hid, range);
395 		entry->range = range;
396 	}
397 
398 	return count;
399 }
400 
401 #ifdef CONFIG_LEDS_CLASS
402 static void lg4ff_set_leds(struct hid_device *hid, __u8 leds)
403 {
404 	struct list_head *report_list = &hid->report_enum[HID_OUTPUT_REPORT].report_list;
405 	struct hid_report *report = list_entry(report_list->next, struct hid_report, list);
406 	__s32 *value = report->field[0]->value;
407 
408 	value[0] = 0xf8;
409 	value[1] = 0x12;
410 	value[2] = leds;
411 	value[3] = 0x00;
412 	value[4] = 0x00;
413 	value[5] = 0x00;
414 	value[6] = 0x00;
415 	hid_hw_request(hid, report, HID_REQ_SET_REPORT);
416 }
417 
418 static void lg4ff_led_set_brightness(struct led_classdev *led_cdev,
419 			enum led_brightness value)
420 {
421 	struct device *dev = led_cdev->dev->parent;
422 	struct hid_device *hid = container_of(dev, struct hid_device, dev);
423 	struct lg_drv_data *drv_data = hid_get_drvdata(hid);
424 	struct lg4ff_device_entry *entry;
425 	int i, state = 0;
426 
427 	if (!drv_data) {
428 		hid_err(hid, "Device data not found.");
429 		return;
430 	}
431 
432 	entry = (struct lg4ff_device_entry *)drv_data->device_props;
433 
434 	if (!entry) {
435 		hid_err(hid, "Device properties not found.");
436 		return;
437 	}
438 
439 	for (i = 0; i < 5; i++) {
440 		if (led_cdev != entry->led[i])
441 			continue;
442 		state = (entry->led_state >> i) & 1;
443 		if (value == LED_OFF && state) {
444 			entry->led_state &= ~(1 << i);
445 			lg4ff_set_leds(hid, entry->led_state);
446 		} else if (value != LED_OFF && !state) {
447 			entry->led_state |= 1 << i;
448 			lg4ff_set_leds(hid, entry->led_state);
449 		}
450 		break;
451 	}
452 }
453 
454 static enum led_brightness lg4ff_led_get_brightness(struct led_classdev *led_cdev)
455 {
456 	struct device *dev = led_cdev->dev->parent;
457 	struct hid_device *hid = container_of(dev, struct hid_device, dev);
458 	struct lg_drv_data *drv_data = hid_get_drvdata(hid);
459 	struct lg4ff_device_entry *entry;
460 	int i, value = 0;
461 
462 	if (!drv_data) {
463 		hid_err(hid, "Device data not found.");
464 		return LED_OFF;
465 	}
466 
467 	entry = (struct lg4ff_device_entry *)drv_data->device_props;
468 
469 	if (!entry) {
470 		hid_err(hid, "Device properties not found.");
471 		return LED_OFF;
472 	}
473 
474 	for (i = 0; i < 5; i++)
475 		if (led_cdev == entry->led[i]) {
476 			value = (entry->led_state >> i) & 1;
477 			break;
478 		}
479 
480 	return value ? LED_FULL : LED_OFF;
481 }
482 #endif
483 
484 int lg4ff_init(struct hid_device *hid)
485 {
486 	struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
487 	struct input_dev *dev = hidinput->input;
488 	struct lg4ff_device_entry *entry;
489 	struct lg_drv_data *drv_data;
490 	struct usb_device_descriptor *udesc;
491 	int error, i, j;
492 	__u16 bcdDevice, rev_maj, rev_min;
493 
494 	/* Check that the report looks ok */
495 	if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
496 		return -1;
497 
498 	/* Check what wheel has been connected */
499 	for (i = 0; i < ARRAY_SIZE(lg4ff_devices); i++) {
500 		if (hid->product == lg4ff_devices[i].product_id) {
501 			dbg_hid("Found compatible device, product ID %04X\n", lg4ff_devices[i].product_id);
502 			break;
503 		}
504 	}
505 
506 	if (i == ARRAY_SIZE(lg4ff_devices)) {
507 		hid_err(hid, "Device is not supported by lg4ff driver. If you think it should be, consider reporting a bug to"
508 			     "LKML, Simon Wood <simon@mungewell.org> or Michal Maly <madcatxster@gmail.com>\n");
509 		return -1;
510 	}
511 
512 	/* Attempt to switch wheel to native mode when applicable */
513 	udesc = &(hid_to_usb_dev(hid)->descriptor);
514 	if (!udesc) {
515 		hid_err(hid, "NULL USB device descriptor\n");
516 		return -1;
517 	}
518 	bcdDevice = le16_to_cpu(udesc->bcdDevice);
519 	rev_maj = bcdDevice >> 8;
520 	rev_min = bcdDevice & 0xff;
521 
522 	if (lg4ff_devices[i].product_id == USB_DEVICE_ID_LOGITECH_WHEEL) {
523 		dbg_hid("Generic wheel detected, can it do native?\n");
524 		dbg_hid("USB revision: %2x.%02x\n", rev_maj, rev_min);
525 
526 		for (j = 0; j < ARRAY_SIZE(lg4ff_revs); j++) {
527 			if (lg4ff_revs[j].rev_maj == rev_maj && lg4ff_revs[j].rev_min == rev_min) {
528 				hid_lg4ff_switch_native(hid, lg4ff_revs[j].command);
529 				hid_info(hid, "Switched to native mode\n");
530 			}
531 		}
532 	}
533 
534 	/* Set supported force feedback capabilities */
535 	for (j = 0; lg4ff_devices[i].ff_effects[j] >= 0; j++)
536 		set_bit(lg4ff_devices[i].ff_effects[j], dev->ffbit);
537 
538 	error = input_ff_create_memless(dev, NULL, hid_lg4ff_play);
539 
540 	if (error)
541 		return error;
542 
543 	/* Check if autocentering is available and
544 	 * set the centering force to zero by default */
545 	if (test_bit(FF_AUTOCENTER, dev->ffbit)) {
546 		if (rev_maj == FFEX_REV_MAJ && rev_min == FFEX_REV_MIN)	/* Formula Force EX expects different autocentering command */
547 			dev->ff->set_autocenter = hid_lg4ff_set_autocenter_ffex;
548 		else
549 			dev->ff->set_autocenter = hid_lg4ff_set_autocenter_default;
550 
551 		dev->ff->set_autocenter(dev, 0);
552 	}
553 
554 	/* Get private driver data */
555 	drv_data = hid_get_drvdata(hid);
556 	if (!drv_data) {
557 		hid_err(hid, "Cannot add device, private driver data not allocated\n");
558 		return -1;
559 	}
560 
561 	/* Initialize device properties */
562 	entry = kzalloc(sizeof(struct lg4ff_device_entry), GFP_KERNEL);
563 	if (!entry) {
564 		hid_err(hid, "Cannot add device, insufficient memory to allocate device properties.\n");
565 		return -ENOMEM;
566 	}
567 	drv_data->device_props = entry;
568 
569 	entry->product_id = lg4ff_devices[i].product_id;
570 	entry->min_range = lg4ff_devices[i].min_range;
571 	entry->max_range = lg4ff_devices[i].max_range;
572 	entry->set_range = lg4ff_devices[i].set_range;
573 
574 	/* Create sysfs interface */
575 	error = device_create_file(&hid->dev, &dev_attr_range);
576 	if (error)
577 		return error;
578 	dbg_hid("sysfs interface created\n");
579 
580 	/* Set the maximum range to start with */
581 	entry->range = entry->max_range;
582 	if (entry->set_range != NULL)
583 		entry->set_range(hid, entry->range);
584 
585 #ifdef CONFIG_LEDS_CLASS
586 	/* register led subsystem - G27 only */
587 	entry->led_state = 0;
588 	for (j = 0; j < 5; j++)
589 		entry->led[j] = NULL;
590 
591 	if (lg4ff_devices[i].product_id == USB_DEVICE_ID_LOGITECH_G27_WHEEL) {
592 		struct led_classdev *led;
593 		size_t name_sz;
594 		char *name;
595 
596 		lg4ff_set_leds(hid, 0);
597 
598 		name_sz = strlen(dev_name(&hid->dev)) + 8;
599 
600 		for (j = 0; j < 5; j++) {
601 			led = kzalloc(sizeof(struct led_classdev)+name_sz, GFP_KERNEL);
602 			if (!led) {
603 				hid_err(hid, "can't allocate memory for LED %d\n", j);
604 				goto err;
605 			}
606 
607 			name = (void *)(&led[1]);
608 			snprintf(name, name_sz, "%s::RPM%d", dev_name(&hid->dev), j+1);
609 			led->name = name;
610 			led->brightness = 0;
611 			led->max_brightness = 1;
612 			led->brightness_get = lg4ff_led_get_brightness;
613 			led->brightness_set = lg4ff_led_set_brightness;
614 
615 			entry->led[j] = led;
616 			error = led_classdev_register(&hid->dev, led);
617 
618 			if (error) {
619 				hid_err(hid, "failed to register LED %d. Aborting.\n", j);
620 err:
621 				/* Deregister LEDs (if any) */
622 				for (j = 0; j < 5; j++) {
623 					led = entry->led[j];
624 					entry->led[j] = NULL;
625 					if (!led)
626 						continue;
627 					led_classdev_unregister(led);
628 					kfree(led);
629 				}
630 				goto out;	/* Let the driver continue without LEDs */
631 			}
632 		}
633 	}
634 out:
635 #endif
636 	hid_info(hid, "Force feedback support for Logitech Gaming Wheels\n");
637 	return 0;
638 }
639 
640 
641 
642 int lg4ff_deinit(struct hid_device *hid)
643 {
644 	struct lg4ff_device_entry *entry;
645 	struct lg_drv_data *drv_data;
646 
647 	device_remove_file(&hid->dev, &dev_attr_range);
648 
649 	drv_data = hid_get_drvdata(hid);
650 	if (!drv_data) {
651 		hid_err(hid, "Error while deinitializing device, no private driver data.\n");
652 		return -1;
653 	}
654 	entry = drv_data->device_props;
655 	if (!entry) {
656 		hid_err(hid, "Error while deinitializing device, no device properties data.\n");
657 		return -1;
658 	}
659 
660 #ifdef CONFIG_LEDS_CLASS
661 	{
662 		int j;
663 		struct led_classdev *led;
664 
665 		/* Deregister LEDs (if any) */
666 		for (j = 0; j < 5; j++) {
667 
668 			led = entry->led[j];
669 			entry->led[j] = NULL;
670 			if (!led)
671 				continue;
672 			led_classdev_unregister(led);
673 			kfree(led);
674 		}
675 	}
676 #endif
677 
678 	/* Deallocate memory */
679 	kfree(entry);
680 
681 	dbg_hid("Device successfully unregistered\n");
682 	return 0;
683 }
684