xref: /linux/drivers/hid/hid-roccat-kone.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Roccat Kone driver for Linux
4  *
5  * Copyright (c) 2010 Stefan Achatz <erazor_de@users.sourceforge.net>
6  */
7 
8 /*
9  */
10 
11 /*
12  * Roccat Kone is a gamer mouse which consists of a mouse part and a keyboard
13  * part. The keyboard part enables the mouse to execute stored macros with mixed
14  * key- and button-events.
15  *
16  * TODO implement on-the-fly polling-rate change
17  *      The windows driver has the ability to change the polling rate of the
18  *      device on the press of a mousebutton.
19  *      Is it possible to remove and reinstall the urb in raw-event- or any
20  *      other handler, or to defer this action to be executed somewhere else?
21  *
22  * TODO is it possible to overwrite group for sysfs attributes via udev?
23  */
24 
25 #include <linux/device.h>
26 #include <linux/input.h>
27 #include <linux/hid.h>
28 #include <linux/module.h>
29 #include <linux/slab.h>
30 #include <linux/hid-roccat.h>
31 #include "hid-ids.h"
32 #include "hid-roccat-common.h"
33 #include "hid-roccat-kone.h"
34 
35 static uint profile_numbers[5] = {0, 1, 2, 3, 4};
36 
37 static void kone_profile_activated(struct kone_device *kone, uint new_profile)
38 {
39 	kone->actual_profile = new_profile;
40 	kone->actual_dpi = kone->profiles[new_profile - 1].startup_dpi;
41 }
42 
43 static void kone_profile_report(struct kone_device *kone, uint new_profile)
44 {
45 	struct kone_roccat_report roccat_report;
46 
47 	roccat_report.event = kone_mouse_event_switch_profile;
48 	roccat_report.value = new_profile;
49 	roccat_report.key = 0;
50 	roccat_report_event(kone->chrdev_minor, (uint8_t *)&roccat_report);
51 }
52 
53 static int kone_receive(struct usb_device *usb_dev, uint usb_command,
54 		void *data, uint size)
55 {
56 	char *buf;
57 	int len;
58 
59 	buf = kmalloc(size, GFP_KERNEL);
60 	if (buf == NULL)
61 		return -ENOMEM;
62 
63 	len = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
64 			HID_REQ_GET_REPORT,
65 			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
66 			usb_command, 0, buf, size, USB_CTRL_SET_TIMEOUT);
67 
68 	memcpy(data, buf, size);
69 	kfree(buf);
70 	return ((len < 0) ? len : ((len != size) ? -EIO : 0));
71 }
72 
73 static int kone_send(struct usb_device *usb_dev, uint usb_command,
74 		void const *data, uint size)
75 {
76 	char *buf;
77 	int len;
78 
79 	buf = kmemdup(data, size, GFP_KERNEL);
80 	if (buf == NULL)
81 		return -ENOMEM;
82 
83 	len = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
84 			HID_REQ_SET_REPORT,
85 			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
86 			usb_command, 0, buf, size, USB_CTRL_SET_TIMEOUT);
87 
88 	kfree(buf);
89 	return ((len < 0) ? len : ((len != size) ? -EIO : 0));
90 }
91 
92 /* kone_class is used for creating sysfs attributes via roccat char device */
93 static struct class *kone_class;
94 
95 static void kone_set_settings_checksum(struct kone_settings *settings)
96 {
97 	uint16_t checksum = 0;
98 	unsigned char *address = (unsigned char *)settings;
99 	int i;
100 
101 	for (i = 0; i < sizeof(struct kone_settings) - 2; ++i, ++address)
102 		checksum += *address;
103 	settings->checksum = cpu_to_le16(checksum);
104 }
105 
106 /*
107  * Checks success after writing data to mouse
108  * On success returns 0
109  * On failure returns errno
110  */
111 static int kone_check_write(struct usb_device *usb_dev)
112 {
113 	int retval;
114 	uint8_t data;
115 
116 	do {
117 		/*
118 		 * Mouse needs 50 msecs until it says ok, but there are
119 		 * 30 more msecs needed for next write to work.
120 		 */
121 		msleep(80);
122 
123 		retval = kone_receive(usb_dev,
124 				kone_command_confirm_write, &data, 1);
125 		if (retval)
126 			return retval;
127 
128 		/*
129 		 * value of 3 seems to mean something like
130 		 * "not finished yet, but it looks good"
131 		 * So check again after a moment.
132 		 */
133 	} while (data == 3);
134 
135 	if (data == 1) /* everything alright */
136 		return 0;
137 
138 	/* unknown answer */
139 	dev_err(&usb_dev->dev, "got retval %d when checking write\n", data);
140 	return -EIO;
141 }
142 
143 /*
144  * Reads settings from mouse and stores it in @buf
145  * On success returns 0
146  * On failure returns errno
147  */
148 static int kone_get_settings(struct usb_device *usb_dev,
149 		struct kone_settings *buf)
150 {
151 	return kone_receive(usb_dev, kone_command_settings, buf,
152 			sizeof(struct kone_settings));
153 }
154 
155 /*
156  * Writes settings from @buf to mouse
157  * On success returns 0
158  * On failure returns errno
159  */
160 static int kone_set_settings(struct usb_device *usb_dev,
161 		struct kone_settings const *settings)
162 {
163 	int retval;
164 
165 	retval = kone_send(usb_dev, kone_command_settings,
166 			settings, sizeof(struct kone_settings));
167 	if (retval)
168 		return retval;
169 	return kone_check_write(usb_dev);
170 }
171 
172 /*
173  * Reads profile data from mouse and stores it in @buf
174  * @number: profile number to read
175  * On success returns 0
176  * On failure returns errno
177  */
178 static int kone_get_profile(struct usb_device *usb_dev,
179 		struct kone_profile *buf, int number)
180 {
181 	int len;
182 
183 	if (number < 1 || number > 5)
184 		return -EINVAL;
185 
186 	len = usb_control_msg(usb_dev, usb_rcvctrlpipe(usb_dev, 0),
187 			USB_REQ_CLEAR_FEATURE,
188 			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_IN,
189 			kone_command_profile, number, buf,
190 			sizeof(struct kone_profile), USB_CTRL_SET_TIMEOUT);
191 
192 	if (len != sizeof(struct kone_profile))
193 		return -EIO;
194 
195 	return 0;
196 }
197 
198 /*
199  * Writes profile data to mouse.
200  * @number: profile number to write
201  * On success returns 0
202  * On failure returns errno
203  */
204 static int kone_set_profile(struct usb_device *usb_dev,
205 		struct kone_profile const *profile, int number)
206 {
207 	int len;
208 
209 	if (number < 1 || number > 5)
210 		return -EINVAL;
211 
212 	len = usb_control_msg(usb_dev, usb_sndctrlpipe(usb_dev, 0),
213 			USB_REQ_SET_CONFIGURATION,
214 			USB_TYPE_CLASS | USB_RECIP_INTERFACE | USB_DIR_OUT,
215 			kone_command_profile, number, (void *)profile,
216 			sizeof(struct kone_profile),
217 			USB_CTRL_SET_TIMEOUT);
218 
219 	if (len != sizeof(struct kone_profile))
220 		return len;
221 
222 	if (kone_check_write(usb_dev))
223 		return -EIO;
224 
225 	return 0;
226 }
227 
228 /*
229  * Reads value of "fast-clip-weight" and stores it in @result
230  * On success returns 0
231  * On failure returns errno
232  */
233 static int kone_get_weight(struct usb_device *usb_dev, int *result)
234 {
235 	int retval;
236 	uint8_t data;
237 
238 	retval = kone_receive(usb_dev, kone_command_weight, &data, 1);
239 
240 	if (retval)
241 		return retval;
242 
243 	*result = (int)data;
244 	return 0;
245 }
246 
247 /*
248  * Reads firmware_version of mouse and stores it in @result
249  * On success returns 0
250  * On failure returns errno
251  */
252 static int kone_get_firmware_version(struct usb_device *usb_dev, int *result)
253 {
254 	int retval;
255 	uint16_t data;
256 
257 	retval = kone_receive(usb_dev, kone_command_firmware_version,
258 			&data, 2);
259 	if (retval)
260 		return retval;
261 
262 	*result = le16_to_cpu(data);
263 	return 0;
264 }
265 
266 static ssize_t kone_sysfs_read_settings(struct file *fp, struct kobject *kobj,
267 		struct bin_attribute *attr, char *buf,
268 		loff_t off, size_t count) {
269 	struct device *dev = kobj_to_dev(kobj)->parent->parent;
270 	struct kone_device *kone = hid_get_drvdata(dev_get_drvdata(dev));
271 
272 	if (off >= sizeof(struct kone_settings))
273 		return 0;
274 
275 	if (off + count > sizeof(struct kone_settings))
276 		count = sizeof(struct kone_settings) - off;
277 
278 	mutex_lock(&kone->kone_lock);
279 	memcpy(buf, ((char const *)&kone->settings) + off, count);
280 	mutex_unlock(&kone->kone_lock);
281 
282 	return count;
283 }
284 
285 /*
286  * Writing settings automatically activates startup_profile.
287  * This function keeps values in kone_device up to date and assumes that in
288  * case of error the old data is still valid
289  */
290 static ssize_t kone_sysfs_write_settings(struct file *fp, struct kobject *kobj,
291 		struct bin_attribute *attr, char *buf,
292 		loff_t off, size_t count) {
293 	struct device *dev = kobj_to_dev(kobj)->parent->parent;
294 	struct kone_device *kone = hid_get_drvdata(dev_get_drvdata(dev));
295 	struct usb_device *usb_dev = interface_to_usbdev(to_usb_interface(dev));
296 	int retval = 0, difference, old_profile;
297 
298 	/* I need to get my data in one piece */
299 	if (off != 0 || count != sizeof(struct kone_settings))
300 		return -EINVAL;
301 
302 	mutex_lock(&kone->kone_lock);
303 	difference = memcmp(buf, &kone->settings, sizeof(struct kone_settings));
304 	if (difference) {
305 		retval = kone_set_settings(usb_dev,
306 				(struct kone_settings const *)buf);
307 		if (retval) {
308 			mutex_unlock(&kone->kone_lock);
309 			return retval;
310 		}
311 
312 		old_profile = kone->settings.startup_profile;
313 		memcpy(&kone->settings, buf, sizeof(struct kone_settings));
314 
315 		kone_profile_activated(kone, kone->settings.startup_profile);
316 
317 		if (kone->settings.startup_profile != old_profile)
318 			kone_profile_report(kone, kone->settings.startup_profile);
319 	}
320 	mutex_unlock(&kone->kone_lock);
321 
322 	return sizeof(struct kone_settings);
323 }
324 static BIN_ATTR(settings, 0660, kone_sysfs_read_settings,
325 		kone_sysfs_write_settings, sizeof(struct kone_settings));
326 
327 static ssize_t kone_sysfs_read_profilex(struct file *fp,
328 		struct kobject *kobj, struct bin_attribute *attr,
329 		char *buf, loff_t off, size_t count) {
330 	struct device *dev = kobj_to_dev(kobj)->parent->parent;
331 	struct kone_device *kone = hid_get_drvdata(dev_get_drvdata(dev));
332 
333 	if (off >= sizeof(struct kone_profile))
334 		return 0;
335 
336 	if (off + count > sizeof(struct kone_profile))
337 		count = sizeof(struct kone_profile) - off;
338 
339 	mutex_lock(&kone->kone_lock);
340 	memcpy(buf, ((char const *)&kone->profiles[*(uint *)(attr->private)]) + off, count);
341 	mutex_unlock(&kone->kone_lock);
342 
343 	return count;
344 }
345 
346 /* Writes data only if different to stored data */
347 static ssize_t kone_sysfs_write_profilex(struct file *fp,
348 		struct kobject *kobj, struct bin_attribute *attr,
349 		char *buf, loff_t off, size_t count) {
350 	struct device *dev = kobj_to_dev(kobj)->parent->parent;
351 	struct kone_device *kone = hid_get_drvdata(dev_get_drvdata(dev));
352 	struct usb_device *usb_dev = interface_to_usbdev(to_usb_interface(dev));
353 	struct kone_profile *profile;
354 	int retval = 0, difference;
355 
356 	/* I need to get my data in one piece */
357 	if (off != 0 || count != sizeof(struct kone_profile))
358 		return -EINVAL;
359 
360 	profile = &kone->profiles[*(uint *)(attr->private)];
361 
362 	mutex_lock(&kone->kone_lock);
363 	difference = memcmp(buf, profile, sizeof(struct kone_profile));
364 	if (difference) {
365 		retval = kone_set_profile(usb_dev,
366 				(struct kone_profile const *)buf,
367 				*(uint *)(attr->private) + 1);
368 		if (!retval)
369 			memcpy(profile, buf, sizeof(struct kone_profile));
370 	}
371 	mutex_unlock(&kone->kone_lock);
372 
373 	if (retval)
374 		return retval;
375 
376 	return sizeof(struct kone_profile);
377 }
378 #define PROFILE_ATTR(number)					\
379 static struct bin_attribute bin_attr_profile##number = {	\
380 	.attr = { .name = "profile" #number, .mode = 0660 },	\
381 	.size = sizeof(struct kone_profile),			\
382 	.read = kone_sysfs_read_profilex,			\
383 	.write = kone_sysfs_write_profilex,			\
384 	.private = &profile_numbers[number-1],			\
385 }
386 PROFILE_ATTR(1);
387 PROFILE_ATTR(2);
388 PROFILE_ATTR(3);
389 PROFILE_ATTR(4);
390 PROFILE_ATTR(5);
391 
392 static ssize_t kone_sysfs_show_actual_profile(struct device *dev,
393 		struct device_attribute *attr, char *buf)
394 {
395 	struct kone_device *kone =
396 			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
397 	return snprintf(buf, PAGE_SIZE, "%d\n", kone->actual_profile);
398 }
399 static DEVICE_ATTR(actual_profile, 0440, kone_sysfs_show_actual_profile, NULL);
400 
401 static ssize_t kone_sysfs_show_actual_dpi(struct device *dev,
402 		struct device_attribute *attr, char *buf)
403 {
404 	struct kone_device *kone =
405 			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
406 	return snprintf(buf, PAGE_SIZE, "%d\n", kone->actual_dpi);
407 }
408 static DEVICE_ATTR(actual_dpi, 0440, kone_sysfs_show_actual_dpi, NULL);
409 
410 /* weight is read each time, since we don't get informed when it's changed */
411 static ssize_t kone_sysfs_show_weight(struct device *dev,
412 		struct device_attribute *attr, char *buf)
413 {
414 	struct kone_device *kone;
415 	struct usb_device *usb_dev;
416 	int weight = 0;
417 	int retval;
418 
419 	dev = dev->parent->parent;
420 	kone = hid_get_drvdata(dev_get_drvdata(dev));
421 	usb_dev = interface_to_usbdev(to_usb_interface(dev));
422 
423 	mutex_lock(&kone->kone_lock);
424 	retval = kone_get_weight(usb_dev, &weight);
425 	mutex_unlock(&kone->kone_lock);
426 
427 	if (retval)
428 		return retval;
429 	return snprintf(buf, PAGE_SIZE, "%d\n", weight);
430 }
431 static DEVICE_ATTR(weight, 0440, kone_sysfs_show_weight, NULL);
432 
433 static ssize_t kone_sysfs_show_firmware_version(struct device *dev,
434 		struct device_attribute *attr, char *buf)
435 {
436 	struct kone_device *kone =
437 			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
438 	return snprintf(buf, PAGE_SIZE, "%d\n", kone->firmware_version);
439 }
440 static DEVICE_ATTR(firmware_version, 0440, kone_sysfs_show_firmware_version,
441 		   NULL);
442 
443 static ssize_t kone_sysfs_show_tcu(struct device *dev,
444 		struct device_attribute *attr, char *buf)
445 {
446 	struct kone_device *kone =
447 			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
448 	return snprintf(buf, PAGE_SIZE, "%d\n", kone->settings.tcu);
449 }
450 
451 static int kone_tcu_command(struct usb_device *usb_dev, int number)
452 {
453 	unsigned char value;
454 
455 	value = number;
456 	return kone_send(usb_dev, kone_command_calibrate, &value, 1);
457 }
458 
459 /*
460  * Calibrating the tcu is the only action that changes settings data inside the
461  * mouse, so this data needs to be reread
462  */
463 static ssize_t kone_sysfs_set_tcu(struct device *dev,
464 		struct device_attribute *attr, char const *buf, size_t size)
465 {
466 	struct kone_device *kone;
467 	struct usb_device *usb_dev;
468 	int retval;
469 	unsigned long state;
470 
471 	dev = dev->parent->parent;
472 	kone = hid_get_drvdata(dev_get_drvdata(dev));
473 	usb_dev = interface_to_usbdev(to_usb_interface(dev));
474 
475 	retval = kstrtoul(buf, 10, &state);
476 	if (retval)
477 		return retval;
478 
479 	if (state != 0 && state != 1)
480 		return -EINVAL;
481 
482 	mutex_lock(&kone->kone_lock);
483 
484 	if (state == 1) { /* state activate */
485 		retval = kone_tcu_command(usb_dev, 1);
486 		if (retval)
487 			goto exit_unlock;
488 		retval = kone_tcu_command(usb_dev, 2);
489 		if (retval)
490 			goto exit_unlock;
491 		ssleep(5); /* tcu needs this time for calibration */
492 		retval = kone_tcu_command(usb_dev, 3);
493 		if (retval)
494 			goto exit_unlock;
495 		retval = kone_tcu_command(usb_dev, 0);
496 		if (retval)
497 			goto exit_unlock;
498 		retval = kone_tcu_command(usb_dev, 4);
499 		if (retval)
500 			goto exit_unlock;
501 		/*
502 		 * Kone needs this time to settle things.
503 		 * Reading settings too early will result in invalid data.
504 		 * Roccat's driver waits 1 sec, maybe this time could be
505 		 * shortened.
506 		 */
507 		ssleep(1);
508 	}
509 
510 	/* calibration changes values in settings, so reread */
511 	retval = kone_get_settings(usb_dev, &kone->settings);
512 	if (retval)
513 		goto exit_no_settings;
514 
515 	/* only write settings back if activation state is different */
516 	if (kone->settings.tcu != state) {
517 		kone->settings.tcu = state;
518 		kone_set_settings_checksum(&kone->settings);
519 
520 		retval = kone_set_settings(usb_dev, &kone->settings);
521 		if (retval) {
522 			dev_err(&usb_dev->dev, "couldn't set tcu state\n");
523 			/*
524 			 * try to reread valid settings into buffer overwriting
525 			 * first error code
526 			 */
527 			retval = kone_get_settings(usb_dev, &kone->settings);
528 			if (retval)
529 				goto exit_no_settings;
530 			goto exit_unlock;
531 		}
532 		/* calibration resets profile */
533 		kone_profile_activated(kone, kone->settings.startup_profile);
534 	}
535 
536 	retval = size;
537 exit_no_settings:
538 	dev_err(&usb_dev->dev, "couldn't read settings\n");
539 exit_unlock:
540 	mutex_unlock(&kone->kone_lock);
541 	return retval;
542 }
543 static DEVICE_ATTR(tcu, 0660, kone_sysfs_show_tcu, kone_sysfs_set_tcu);
544 
545 static ssize_t kone_sysfs_show_startup_profile(struct device *dev,
546 		struct device_attribute *attr, char *buf)
547 {
548 	struct kone_device *kone =
549 			hid_get_drvdata(dev_get_drvdata(dev->parent->parent));
550 	return snprintf(buf, PAGE_SIZE, "%d\n", kone->settings.startup_profile);
551 }
552 
553 static ssize_t kone_sysfs_set_startup_profile(struct device *dev,
554 		struct device_attribute *attr, char const *buf, size_t size)
555 {
556 	struct kone_device *kone;
557 	struct usb_device *usb_dev;
558 	int retval;
559 	unsigned long new_startup_profile;
560 
561 	dev = dev->parent->parent;
562 	kone = hid_get_drvdata(dev_get_drvdata(dev));
563 	usb_dev = interface_to_usbdev(to_usb_interface(dev));
564 
565 	retval = kstrtoul(buf, 10, &new_startup_profile);
566 	if (retval)
567 		return retval;
568 
569 	if (new_startup_profile  < 1 || new_startup_profile > 5)
570 		return -EINVAL;
571 
572 	mutex_lock(&kone->kone_lock);
573 
574 	kone->settings.startup_profile = new_startup_profile;
575 	kone_set_settings_checksum(&kone->settings);
576 
577 	retval = kone_set_settings(usb_dev, &kone->settings);
578 	if (retval) {
579 		mutex_unlock(&kone->kone_lock);
580 		return retval;
581 	}
582 
583 	/* changing the startup profile immediately activates this profile */
584 	kone_profile_activated(kone, new_startup_profile);
585 	kone_profile_report(kone, new_startup_profile);
586 
587 	mutex_unlock(&kone->kone_lock);
588 	return size;
589 }
590 static DEVICE_ATTR(startup_profile, 0660, kone_sysfs_show_startup_profile,
591 		   kone_sysfs_set_startup_profile);
592 
593 static struct attribute *kone_attrs[] = {
594 	/*
595 	 * Read actual dpi settings.
596 	 * Returns raw value for further processing. Refer to enum
597 	 * kone_polling_rates to get real value.
598 	 */
599 	&dev_attr_actual_dpi.attr,
600 	&dev_attr_actual_profile.attr,
601 
602 	/*
603 	 * The mouse can be equipped with one of four supplied weights from 5
604 	 * to 20 grams which are recognized and its value can be read out.
605 	 * This returns the raw value reported by the mouse for easy evaluation
606 	 * by software. Refer to enum kone_weights to get corresponding real
607 	 * weight.
608 	 */
609 	&dev_attr_weight.attr,
610 
611 	/*
612 	 * Prints firmware version stored in mouse as integer.
613 	 * The raw value reported by the mouse is returned for easy evaluation,
614 	 * to get the real version number the decimal point has to be shifted 2
615 	 * positions to the left. E.g. a value of 138 means 1.38.
616 	 */
617 	&dev_attr_firmware_version.attr,
618 
619 	/*
620 	 * Prints state of Tracking Control Unit as number where 0 = off and
621 	 * 1 = on. Writing 0 deactivates tcu and writing 1 calibrates and
622 	 * activates the tcu
623 	 */
624 	&dev_attr_tcu.attr,
625 
626 	/* Prints and takes the number of the profile the mouse starts with */
627 	&dev_attr_startup_profile.attr,
628 	NULL,
629 };
630 
631 static struct bin_attribute *kone_bin_attributes[] = {
632 	&bin_attr_settings,
633 	&bin_attr_profile1,
634 	&bin_attr_profile2,
635 	&bin_attr_profile3,
636 	&bin_attr_profile4,
637 	&bin_attr_profile5,
638 	NULL,
639 };
640 
641 static const struct attribute_group kone_group = {
642 	.attrs = kone_attrs,
643 	.bin_attrs = kone_bin_attributes,
644 };
645 
646 static const struct attribute_group *kone_groups[] = {
647 	&kone_group,
648 	NULL,
649 };
650 
651 static int kone_init_kone_device_struct(struct usb_device *usb_dev,
652 		struct kone_device *kone)
653 {
654 	uint i;
655 	int retval;
656 
657 	mutex_init(&kone->kone_lock);
658 
659 	for (i = 0; i < 5; ++i) {
660 		retval = kone_get_profile(usb_dev, &kone->profiles[i], i + 1);
661 		if (retval)
662 			return retval;
663 	}
664 
665 	retval = kone_get_settings(usb_dev, &kone->settings);
666 	if (retval)
667 		return retval;
668 
669 	retval = kone_get_firmware_version(usb_dev, &kone->firmware_version);
670 	if (retval)
671 		return retval;
672 
673 	kone_profile_activated(kone, kone->settings.startup_profile);
674 
675 	return 0;
676 }
677 
678 /*
679  * Since IGNORE_MOUSE quirk moved to hid-apple, there is no way to bind only to
680  * mousepart if usb_hid is compiled into the kernel and kone is compiled as
681  * module.
682  * Secial behaviour is bound only to mousepart since only mouseevents contain
683  * additional notifications.
684  */
685 static int kone_init_specials(struct hid_device *hdev)
686 {
687 	struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
688 	struct usb_device *usb_dev = interface_to_usbdev(intf);
689 	struct kone_device *kone;
690 	int retval;
691 
692 	if (intf->cur_altsetting->desc.bInterfaceProtocol
693 			== USB_INTERFACE_PROTOCOL_MOUSE) {
694 
695 		kone = kzalloc(sizeof(*kone), GFP_KERNEL);
696 		if (!kone)
697 			return -ENOMEM;
698 		hid_set_drvdata(hdev, kone);
699 
700 		retval = kone_init_kone_device_struct(usb_dev, kone);
701 		if (retval) {
702 			hid_err(hdev, "couldn't init struct kone_device\n");
703 			goto exit_free;
704 		}
705 
706 		retval = roccat_connect(kone_class, hdev,
707 				sizeof(struct kone_roccat_report));
708 		if (retval < 0) {
709 			hid_err(hdev, "couldn't init char dev\n");
710 			/* be tolerant about not getting chrdev */
711 		} else {
712 			kone->roccat_claimed = 1;
713 			kone->chrdev_minor = retval;
714 		}
715 	} else {
716 		hid_set_drvdata(hdev, NULL);
717 	}
718 
719 	return 0;
720 exit_free:
721 	kfree(kone);
722 	return retval;
723 }
724 
725 static void kone_remove_specials(struct hid_device *hdev)
726 {
727 	struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
728 	struct kone_device *kone;
729 
730 	if (intf->cur_altsetting->desc.bInterfaceProtocol
731 			== USB_INTERFACE_PROTOCOL_MOUSE) {
732 		kone = hid_get_drvdata(hdev);
733 		if (kone->roccat_claimed)
734 			roccat_disconnect(kone->chrdev_minor);
735 		kfree(hid_get_drvdata(hdev));
736 	}
737 }
738 
739 static int kone_probe(struct hid_device *hdev, const struct hid_device_id *id)
740 {
741 	int retval;
742 
743 	retval = hid_parse(hdev);
744 	if (retval) {
745 		hid_err(hdev, "parse failed\n");
746 		goto exit;
747 	}
748 
749 	retval = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
750 	if (retval) {
751 		hid_err(hdev, "hw start failed\n");
752 		goto exit;
753 	}
754 
755 	retval = kone_init_specials(hdev);
756 	if (retval) {
757 		hid_err(hdev, "couldn't install mouse\n");
758 		goto exit_stop;
759 	}
760 
761 	return 0;
762 
763 exit_stop:
764 	hid_hw_stop(hdev);
765 exit:
766 	return retval;
767 }
768 
769 static void kone_remove(struct hid_device *hdev)
770 {
771 	kone_remove_specials(hdev);
772 	hid_hw_stop(hdev);
773 }
774 
775 /* handle special events and keep actual profile and dpi values up to date */
776 static void kone_keep_values_up_to_date(struct kone_device *kone,
777 		struct kone_mouse_event const *event)
778 {
779 	switch (event->event) {
780 	case kone_mouse_event_switch_profile:
781 		kone->actual_dpi = kone->profiles[event->value - 1].
782 				startup_dpi;
783 		/* fall through */
784 	case kone_mouse_event_osd_profile:
785 		kone->actual_profile = event->value;
786 		break;
787 	case kone_mouse_event_switch_dpi:
788 	case kone_mouse_event_osd_dpi:
789 		kone->actual_dpi = event->value;
790 		break;
791 	}
792 }
793 
794 static void kone_report_to_chrdev(struct kone_device const *kone,
795 		struct kone_mouse_event const *event)
796 {
797 	struct kone_roccat_report roccat_report;
798 
799 	switch (event->event) {
800 	case kone_mouse_event_switch_profile:
801 	case kone_mouse_event_switch_dpi:
802 	case kone_mouse_event_osd_profile:
803 	case kone_mouse_event_osd_dpi:
804 		roccat_report.event = event->event;
805 		roccat_report.value = event->value;
806 		roccat_report.key = 0;
807 		roccat_report_event(kone->chrdev_minor,
808 				(uint8_t *)&roccat_report);
809 		break;
810 	case kone_mouse_event_call_overlong_macro:
811 	case kone_mouse_event_multimedia:
812 		if (event->value == kone_keystroke_action_press) {
813 			roccat_report.event = event->event;
814 			roccat_report.value = kone->actual_profile;
815 			roccat_report.key = event->macro_key;
816 			roccat_report_event(kone->chrdev_minor,
817 					(uint8_t *)&roccat_report);
818 		}
819 		break;
820 	}
821 
822 }
823 
824 /*
825  * Is called for keyboard- and mousepart.
826  * Only mousepart gets informations about special events in its extended event
827  * structure.
828  */
829 static int kone_raw_event(struct hid_device *hdev, struct hid_report *report,
830 		u8 *data, int size)
831 {
832 	struct kone_device *kone = hid_get_drvdata(hdev);
833 	struct kone_mouse_event *event = (struct kone_mouse_event *)data;
834 
835 	/* keyboard events are always processed by default handler */
836 	if (size != sizeof(struct kone_mouse_event))
837 		return 0;
838 
839 	if (kone == NULL)
840 		return 0;
841 
842 	/*
843 	 * Firmware 1.38 introduced new behaviour for tilt and special buttons.
844 	 * Pressed button is reported in each movement event.
845 	 * Workaround sends only one event per press.
846 	 */
847 	if (memcmp(&kone->last_mouse_event.tilt, &event->tilt, 5))
848 		memcpy(&kone->last_mouse_event, event,
849 				sizeof(struct kone_mouse_event));
850 	else
851 		memset(&event->tilt, 0, 5);
852 
853 	kone_keep_values_up_to_date(kone, event);
854 
855 	if (kone->roccat_claimed)
856 		kone_report_to_chrdev(kone, event);
857 
858 	return 0; /* always do further processing */
859 }
860 
861 static const struct hid_device_id kone_devices[] = {
862 	{ HID_USB_DEVICE(USB_VENDOR_ID_ROCCAT, USB_DEVICE_ID_ROCCAT_KONE) },
863 	{ }
864 };
865 
866 MODULE_DEVICE_TABLE(hid, kone_devices);
867 
868 static struct hid_driver kone_driver = {
869 		.name = "kone",
870 		.id_table = kone_devices,
871 		.probe = kone_probe,
872 		.remove = kone_remove,
873 		.raw_event = kone_raw_event
874 };
875 
876 static int __init kone_init(void)
877 {
878 	int retval;
879 
880 	/* class name has to be same as driver name */
881 	kone_class = class_create(THIS_MODULE, "kone");
882 	if (IS_ERR(kone_class))
883 		return PTR_ERR(kone_class);
884 	kone_class->dev_groups = kone_groups;
885 
886 	retval = hid_register_driver(&kone_driver);
887 	if (retval)
888 		class_destroy(kone_class);
889 	return retval;
890 }
891 
892 static void __exit kone_exit(void)
893 {
894 	hid_unregister_driver(&kone_driver);
895 	class_destroy(kone_class);
896 }
897 
898 module_init(kone_init);
899 module_exit(kone_exit);
900 
901 MODULE_AUTHOR("Stefan Achatz");
902 MODULE_DESCRIPTION("USB Roccat Kone driver");
903 MODULE_LICENSE("GPL v2");
904