1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * MSI GT683R led driver
4 *
5 * Copyright (c) 2014 Janne Kanniainen <janne.kanniainen@gmail.com>
6 */
7
8 #include <linux/device.h>
9 #include <linux/hid.h>
10 #include <linux/kernel.h>
11 #include <linux/leds.h>
12 #include <linux/module.h>
13
14 #include "hid-ids.h"
15
16 #define GT683R_BUFFER_SIZE 8
17
18 /*
19 * GT683R_LED_OFF: all LEDs are off
20 * GT683R_LED_AUDIO: LEDs brightness depends on sound level
21 * GT683R_LED_BREATHING: LEDs brightness varies at human breathing rate
22 * GT683R_LED_NORMAL: LEDs are fully on when enabled
23 */
24 enum gt683r_led_mode {
25 GT683R_LED_OFF = 0,
26 GT683R_LED_AUDIO = 2,
27 GT683R_LED_BREATHING = 3,
28 GT683R_LED_NORMAL = 5
29 };
30
31 enum gt683r_panels {
32 GT683R_LED_BACK = 0,
33 GT683R_LED_SIDE = 1,
34 GT683R_LED_FRONT = 2,
35 GT683R_LED_COUNT,
36 };
37
38 static const char * const gt683r_panel_names[] = {
39 "back",
40 "side",
41 "front",
42 };
43
44 struct gt683r_led {
45 struct hid_device *hdev;
46 struct led_classdev led_devs[GT683R_LED_COUNT];
47 struct mutex lock;
48 struct work_struct work;
49 enum led_brightness brightnesses[GT683R_LED_COUNT];
50 enum gt683r_led_mode mode;
51 };
52
53 static const struct hid_device_id gt683r_led_id[] = {
54 { HID_USB_DEVICE(USB_VENDOR_ID_MSI, USB_DEVICE_ID_MSI_GT683R_LED_PANEL) },
55 { }
56 };
57
gt683r_brightness_set(struct led_classdev * led_cdev,enum led_brightness brightness)58 static void gt683r_brightness_set(struct led_classdev *led_cdev,
59 enum led_brightness brightness)
60 {
61 int i;
62 struct device *dev = led_cdev->dev->parent;
63 struct hid_device *hdev = to_hid_device(dev);
64 struct gt683r_led *led = hid_get_drvdata(hdev);
65
66 for (i = 0; i < GT683R_LED_COUNT; i++) {
67 if (led_cdev == &led->led_devs[i])
68 break;
69 }
70
71 if (i < GT683R_LED_COUNT) {
72 led->brightnesses[i] = brightness;
73 schedule_work(&led->work);
74 }
75 }
76
mode_show(struct device * dev,struct device_attribute * attr,char * buf)77 static ssize_t mode_show(struct device *dev,
78 struct device_attribute *attr,
79 char *buf)
80 {
81 u8 sysfs_mode;
82 struct hid_device *hdev = to_hid_device(dev->parent);
83 struct gt683r_led *led = hid_get_drvdata(hdev);
84
85 if (led->mode == GT683R_LED_NORMAL)
86 sysfs_mode = 0;
87 else if (led->mode == GT683R_LED_AUDIO)
88 sysfs_mode = 1;
89 else
90 sysfs_mode = 2;
91
92 return scnprintf(buf, PAGE_SIZE, "%u\n", sysfs_mode);
93 }
94
mode_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)95 static ssize_t mode_store(struct device *dev,
96 struct device_attribute *attr,
97 const char *buf, size_t count)
98 {
99 u8 sysfs_mode;
100 struct hid_device *hdev = to_hid_device(dev->parent);
101 struct gt683r_led *led = hid_get_drvdata(hdev);
102
103
104 if (kstrtou8(buf, 10, &sysfs_mode) || sysfs_mode > 2)
105 return -EINVAL;
106
107 mutex_lock(&led->lock);
108
109 if (sysfs_mode == 0)
110 led->mode = GT683R_LED_NORMAL;
111 else if (sysfs_mode == 1)
112 led->mode = GT683R_LED_AUDIO;
113 else
114 led->mode = GT683R_LED_BREATHING;
115
116 mutex_unlock(&led->lock);
117 schedule_work(&led->work);
118
119 return count;
120 }
121
gt683r_led_snd_msg(struct gt683r_led * led,u8 * msg)122 static int gt683r_led_snd_msg(struct gt683r_led *led, u8 *msg)
123 {
124 int ret;
125
126 ret = hid_hw_raw_request(led->hdev, msg[0], msg, GT683R_BUFFER_SIZE,
127 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
128 if (ret != GT683R_BUFFER_SIZE) {
129 hid_err(led->hdev,
130 "failed to send set report request: %i\n", ret);
131 if (ret < 0)
132 return ret;
133 return -EIO;
134 }
135
136 return 0;
137 }
138
gt683r_leds_set(struct gt683r_led * led,u8 leds)139 static int gt683r_leds_set(struct gt683r_led *led, u8 leds)
140 {
141 int ret;
142 u8 *buffer;
143
144 buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
145 if (!buffer)
146 return -ENOMEM;
147
148 buffer[0] = 0x01;
149 buffer[1] = 0x02;
150 buffer[2] = 0x30;
151 buffer[3] = leds;
152 ret = gt683r_led_snd_msg(led, buffer);
153
154 kfree(buffer);
155 return ret;
156 }
157
gt683r_mode_set(struct gt683r_led * led,u8 mode)158 static int gt683r_mode_set(struct gt683r_led *led, u8 mode)
159 {
160 int ret;
161 u8 *buffer;
162
163 buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
164 if (!buffer)
165 return -ENOMEM;
166
167 buffer[0] = 0x01;
168 buffer[1] = 0x02;
169 buffer[2] = 0x20;
170 buffer[3] = mode;
171 buffer[4] = 0x01;
172 ret = gt683r_led_snd_msg(led, buffer);
173
174 kfree(buffer);
175 return ret;
176 }
177
gt683r_led_work(struct work_struct * work)178 static void gt683r_led_work(struct work_struct *work)
179 {
180 int i;
181 u8 leds = 0;
182 u8 mode;
183 struct gt683r_led *led = container_of(work, struct gt683r_led, work);
184
185 mutex_lock(&led->lock);
186
187 for (i = 0; i < GT683R_LED_COUNT; i++) {
188 if (led->brightnesses[i])
189 leds |= BIT(i);
190 }
191
192 if (gt683r_leds_set(led, leds))
193 goto fail;
194
195 if (leds)
196 mode = led->mode;
197 else
198 mode = GT683R_LED_OFF;
199
200 gt683r_mode_set(led, mode);
201 fail:
202 mutex_unlock(&led->lock);
203 }
204
205 static DEVICE_ATTR_RW(mode);
206
207 static struct attribute *gt683r_led_attrs[] = {
208 &dev_attr_mode.attr,
209 NULL
210 };
211
212 static const struct attribute_group gt683r_led_group = {
213 .name = "gt683r",
214 .attrs = gt683r_led_attrs,
215 };
216
217 static const struct attribute_group *gt683r_led_groups[] = {
218 >683r_led_group,
219 NULL
220 };
221
gt683r_led_probe(struct hid_device * hdev,const struct hid_device_id * id)222 static int gt683r_led_probe(struct hid_device *hdev,
223 const struct hid_device_id *id)
224 {
225 int i;
226 int ret;
227 int name_sz;
228 char *name;
229 struct gt683r_led *led;
230
231 led = devm_kzalloc(&hdev->dev, sizeof(*led), GFP_KERNEL);
232 if (!led)
233 return -ENOMEM;
234
235 mutex_init(&led->lock);
236 INIT_WORK(&led->work, gt683r_led_work);
237
238 led->mode = GT683R_LED_NORMAL;
239 led->hdev = hdev;
240 hid_set_drvdata(hdev, led);
241
242 ret = hid_parse(hdev);
243 if (ret) {
244 hid_err(hdev, "hid parsing failed\n");
245 return ret;
246 }
247
248 ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
249 if (ret) {
250 hid_err(hdev, "hw start failed\n");
251 return ret;
252 }
253
254 for (i = 0; i < GT683R_LED_COUNT; i++) {
255 name_sz = strlen(dev_name(&hdev->dev)) +
256 strlen(gt683r_panel_names[i]) + 3;
257
258 name = devm_kzalloc(&hdev->dev, name_sz, GFP_KERNEL);
259 if (!name) {
260 ret = -ENOMEM;
261 goto fail;
262 }
263
264 snprintf(name, name_sz, "%s::%s",
265 dev_name(&hdev->dev), gt683r_panel_names[i]);
266 led->led_devs[i].name = name;
267 led->led_devs[i].max_brightness = 1;
268 led->led_devs[i].brightness_set = gt683r_brightness_set;
269 led->led_devs[i].groups = gt683r_led_groups;
270
271 ret = led_classdev_register(&hdev->dev, &led->led_devs[i]);
272 if (ret) {
273 hid_err(hdev, "could not register led device\n");
274 goto fail;
275 }
276 }
277
278 return 0;
279
280 fail:
281 for (i = i - 1; i >= 0; i--)
282 led_classdev_unregister(&led->led_devs[i]);
283 hid_hw_stop(hdev);
284 return ret;
285 }
286
gt683r_led_remove(struct hid_device * hdev)287 static void gt683r_led_remove(struct hid_device *hdev)
288 {
289 int i;
290 struct gt683r_led *led = hid_get_drvdata(hdev);
291
292 for (i = 0; i < GT683R_LED_COUNT; i++)
293 led_classdev_unregister(&led->led_devs[i]);
294 flush_work(&led->work);
295 hid_hw_stop(hdev);
296 }
297
298 static struct hid_driver gt683r_led_driver = {
299 .probe = gt683r_led_probe,
300 .remove = gt683r_led_remove,
301 .name = "gt683r_led",
302 .id_table = gt683r_led_id,
303 };
304
305 module_hid_driver(gt683r_led_driver);
306
307 MODULE_AUTHOR("Janne Kanniainen");
308 MODULE_DESCRIPTION("MSI GT683R led driver");
309 MODULE_LICENSE("GPL");
310