1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * HID driver for Cougar 500k Gaming Keyboard
4 *
5 * Copyright (c) 2018 Daniel M. Lambea <dmlambea@gmail.com>
6 */
7
8#include <linux/hid.h>
9#include <linux/module.h>
10#include <linux/printk.h>
11
12#include "hid-ids.h"
13
14MODULE_AUTHOR("Daniel M. Lambea <dmlambea@gmail.com>");
15MODULE_DESCRIPTION("Cougar 500k Gaming Keyboard");
16MODULE_LICENSE("GPL");
17MODULE_INFO(key_mappings, "G1-G6 are mapped to F13-F18");
18
19static bool g6_is_space = true;
20MODULE_PARM_DESC(g6_is_space,
21 "If true, G6 programmable key sends SPACE instead of F18 (default=true)");
22
23#define COUGAR_VENDOR_USAGE 0xff00ff00
24
25#define COUGAR_FIELD_CODE 1
26#define COUGAR_FIELD_ACTION 2
27
28#define COUGAR_KEY_G1 0x83
29#define COUGAR_KEY_G2 0x84
30#define COUGAR_KEY_G3 0x85
31#define COUGAR_KEY_G4 0x86
32#define COUGAR_KEY_G5 0x87
33#define COUGAR_KEY_G6 0x78
34#define COUGAR_KEY_FN 0x0d
35#define COUGAR_KEY_MR 0x6f
36#define COUGAR_KEY_M1 0x80
37#define COUGAR_KEY_M2 0x81
38#define COUGAR_KEY_M3 0x82
39#define COUGAR_KEY_LEDS 0x67
40#define COUGAR_KEY_LOCK 0x6e
41
42
43/* Default key mappings. The special key COUGAR_KEY_G6 is defined first
44 * because it is more frequent to use the spacebar rather than any other
45 * special keys. Depending on the value of the parameter 'g6_is_space',
46 * the mapping will be updated in the probe function.
47 */
48static unsigned char cougar_mapping[][2] = {
49 { COUGAR_KEY_G6, KEY_SPACE },
50 { COUGAR_KEY_G1, KEY_F13 },
51 { COUGAR_KEY_G2, KEY_F14 },
52 { COUGAR_KEY_G3, KEY_F15 },
53 { COUGAR_KEY_G4, KEY_F16 },
54 { COUGAR_KEY_G5, KEY_F17 },
55 { COUGAR_KEY_LOCK, KEY_SCREENLOCK },
56/* The following keys are handled by the hardware itself, so no special
57 * treatment is required:
58 { COUGAR_KEY_FN, KEY_RESERVED },
59 { COUGAR_KEY_MR, KEY_RESERVED },
60 { COUGAR_KEY_M1, KEY_RESERVED },
61 { COUGAR_KEY_M2, KEY_RESERVED },
62 { COUGAR_KEY_M3, KEY_RESERVED },
63 { COUGAR_KEY_LEDS, KEY_RESERVED },
64*/
65 { 0, 0 },
66};
67
68struct cougar_shared {
69 struct list_head list;
70 struct kref kref;
71 bool enabled;
72 struct hid_device *dev;
73 struct input_dev *input;
74};
75
76struct cougar {
77 bool special_intf;
78 struct cougar_shared *shared;
79};
80
81static LIST_HEAD(cougar_udev_list);
82static DEFINE_MUTEX(cougar_udev_list_lock);
83
84/**
85 * cougar_fix_g6_mapping - configure the mapping for key G6/Spacebar
86 */
87static void cougar_fix_g6_mapping(void)
88{
89 int i;
90
91 for (i = 0; cougar_mapping[i][0]; i++) {
92 if (cougar_mapping[i][0] == COUGAR_KEY_G6) {
93 cougar_mapping[i][1] =
94 g6_is_space ? KEY_SPACE : KEY_F18;
95 pr_info("cougar: G6 mapped to %s\n",
96 g6_is_space ? "space" : "F18");
97 return;
98 }
99 }
100 pr_warn("cougar: no mappings defined for G6/spacebar");
101}
102
103/*
104 * Constant-friendly rdesc fixup for mouse interface
105 */
106static __u8 *cougar_report_fixup(struct hid_device *hdev, __u8 *rdesc,
107 unsigned int *rsize)
108{
109 if (rdesc[2] == 0x09 && rdesc[3] == 0x02 &&
110 (rdesc[115] | rdesc[116] << 8) >= HID_MAX_USAGES) {
111 hid_info(hdev,
112 "usage count exceeds max: fixing up report descriptor\n");
113 rdesc[115] = ((HID_MAX_USAGES-1) & 0xff);
114 rdesc[116] = ((HID_MAX_USAGES-1) >> 8);
115 }
116 return rdesc;
117}
118
119static struct cougar_shared *cougar_get_shared_data(struct hid_device *hdev)
120{
121 struct cougar_shared *shared;
122
123 /* Try to find an already-probed interface from the same device */
124 list_for_each_entry(shared, &cougar_udev_list, list) {
125 if (hid_compare_device_paths(hdev, shared->dev, '/')) {
126 kref_get(&shared->kref);
127 return shared;
128 }
129 }
130 return NULL;
131}
132
133static void cougar_release_shared_data(struct kref *kref)
134{
135 struct cougar_shared *shared = container_of(kref,
136 struct cougar_shared, kref);
137
138 mutex_lock(&cougar_udev_list_lock);
139 list_del(&shared->list);
140 mutex_unlock(&cougar_udev_list_lock);
141
142 kfree(shared);
143}
144
145static void cougar_remove_shared_data(void *resource)
146{
147 struct cougar *cougar = resource;
148
149 if (cougar->shared) {
150 kref_put(&cougar->shared->kref, cougar_release_shared_data);
151 cougar->shared = NULL;
152 }
153}
154
155/*
156 * Bind the device group's shared data to this cougar struct.
157 * If no shared data exists for this group, create and initialize it.
158 */
159static int cougar_bind_shared_data(struct hid_device *hdev,
160 struct cougar *cougar)
161{
162 struct cougar_shared *shared;
163 int error = 0;
164
165 mutex_lock(&cougar_udev_list_lock);
166
167 shared = cougar_get_shared_data(hdev);
168 if (!shared) {
169 shared = kzalloc(sizeof(*shared), GFP_KERNEL);
170 if (!shared) {
171 error = -ENOMEM;
172 goto out;
173 }
174
175 kref_init(&shared->kref);
176 shared->dev = hdev;
177 list_add_tail(&shared->list, &cougar_udev_list);
178 }
179
180 cougar->shared = shared;
181
182 error = devm_add_action(&hdev->dev, cougar_remove_shared_data, cougar);
183 if (error) {
184 mutex_unlock(&cougar_udev_list_lock);
185 cougar_remove_shared_data(cougar);
186 return error;
187 }
188
189out:
190 mutex_unlock(&cougar_udev_list_lock);
191 return error;
192}
193
194static int cougar_probe(struct hid_device *hdev,
195 const struct hid_device_id *id)
196{
197 struct cougar *cougar;
198 struct hid_input *next, *hidinput = NULL;
199 unsigned int connect_mask;
200 int error;
201
202 cougar = devm_kzalloc(&hdev->dev, sizeof(*cougar), GFP_KERNEL);
203 if (!cougar)
204 return -ENOMEM;
205 hid_set_drvdata(hdev, cougar);
206
207 error = hid_parse(hdev);
208 if (error) {
209 hid_err(hdev, "parse failed\n");
210 goto fail;
211 }
212
213 if (hdev->collection->usage == COUGAR_VENDOR_USAGE) {
214 cougar->special_intf = true;
215 connect_mask = HID_CONNECT_HIDRAW;
216 } else
217 connect_mask = HID_CONNECT_DEFAULT;
218
219 error = hid_hw_start(hdev, connect_mask);
220 if (error) {
221 hid_err(hdev, "hw start failed\n");
222 goto fail;
223 }
224
225 error = cougar_bind_shared_data(hdev, cougar);
226 if (error)
227 goto fail_stop_and_cleanup;
228
229 /* The custom vendor interface will use the hid_input registered
230 * for the keyboard interface, in order to send translated key codes
231 * to it.
232 */
233 if (hdev->collection->usage == HID_GD_KEYBOARD) {
234 list_for_each_entry_safe(hidinput, next, &hdev->inputs, list) {
235 if (hidinput->registered && hidinput->input != NULL) {
236 cougar->shared->input = hidinput->input;
237 cougar->shared->enabled = true;
238 break;
239 }
240 }
241 } else if (hdev->collection->usage == COUGAR_VENDOR_USAGE) {
242 /* Preinit the mapping table */
243 cougar_fix_g6_mapping();
244 error = hid_hw_open(hdev);
245 if (error)
246 goto fail_stop_and_cleanup;
247 }
248 return 0;
249
250fail_stop_and_cleanup:
251 hid_hw_stop(hdev);
252fail:
253 hid_set_drvdata(hdev, NULL);
254 return error;
255}
256
257/*
258 * Convert events from vendor intf to input key events
259 */
260static int cougar_raw_event(struct hid_device *hdev, struct hid_report *report,
261 u8 *data, int size)
262{
263 struct cougar *cougar;
264 struct cougar_shared *shared;
265 unsigned char code, action;
266 int i;
267
268 cougar = hid_get_drvdata(hdev);
269 shared = cougar->shared;
270 if (!cougar->special_intf || !shared)
271 return 0;
272
273 if (!shared->enabled || !shared->input)
274 return -EPERM;
275
276 code = data[COUGAR_FIELD_CODE];
277 action = data[COUGAR_FIELD_ACTION];
278 for (i = 0; cougar_mapping[i][0]; i++) {
279 if (code == cougar_mapping[i][0]) {
280 input_event(shared->input, EV_KEY,
281 cougar_mapping[i][1], action);
282 input_sync(shared->input);
283 return -EPERM;
284 }
285 }
286 /* Avoid warnings on the same unmapped key twice */
287 if (action != 0)
288 hid_warn(hdev, "unmapped special key code %0x: ignoring\n", code);
289 return -EPERM;
290}
291
292static void cougar_remove(struct hid_device *hdev)
293{
294 struct cougar *cougar = hid_get_drvdata(hdev);
295
296 if (cougar) {
297 /* Stop the vendor intf to process more events */
298 if (cougar->shared)
299 cougar->shared->enabled = false;
300 if (cougar->special_intf)
301 hid_hw_close(hdev);
302 }
303 hid_hw_stop(hdev);
304}
305
306static int cougar_param_set_g6_is_space(const char *val,
307 const struct kernel_param *kp)
308{
309 int ret;
310
311 ret = param_set_bool(val, kp);
312 if (ret)
313 return ret;
314
315 cougar_fix_g6_mapping();
316
317 return 0;
318}
319
320static const struct kernel_param_ops cougar_g6_is_space_ops = {
321 .set = cougar_param_set_g6_is_space,
322 .get = param_get_bool,
323};
324module_param_cb(g6_is_space, &cougar_g6_is_space_ops, &g6_is_space, 0644);
325
326static struct hid_device_id cougar_id_table[] = {
327 { HID_USB_DEVICE(USB_VENDOR_ID_SOLID_YEAR,
328 USB_DEVICE_ID_COUGAR_500K_GAMING_KEYBOARD) },
329 { HID_USB_DEVICE(USB_VENDOR_ID_SOLID_YEAR,
330 USB_DEVICE_ID_COUGAR_700K_GAMING_KEYBOARD) },
331 {}
332};
333MODULE_DEVICE_TABLE(hid, cougar_id_table);
334
335static struct hid_driver cougar_driver = {
336 .name = "cougar",
337 .id_table = cougar_id_table,
338 .report_fixup = cougar_report_fixup,
339 .probe = cougar_probe,
340 .remove = cougar_remove,
341 .raw_event = cougar_raw_event,
342};
343
344module_hid_driver(cougar_driver);
345