xref: /linux/drivers/hid/hid-gt683r.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
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 MODULE_DEVICE_TABLE(hid, gt683r_led_id);
58 
59 static void gt683r_brightness_set(struct led_classdev *led_cdev,
60 				enum led_brightness brightness)
61 {
62 	int i;
63 	struct device *dev = led_cdev->dev->parent;
64 	struct hid_device *hdev = to_hid_device(dev);
65 	struct gt683r_led *led = hid_get_drvdata(hdev);
66 
67 	for (i = 0; i < GT683R_LED_COUNT; i++) {
68 		if (led_cdev == &led->led_devs[i])
69 			break;
70 	}
71 
72 	if (i < GT683R_LED_COUNT) {
73 		led->brightnesses[i] = brightness;
74 		schedule_work(&led->work);
75 	}
76 }
77 
78 static ssize_t mode_show(struct device *dev,
79 				struct device_attribute *attr,
80 				char *buf)
81 {
82 	u8 sysfs_mode;
83 	struct hid_device *hdev = to_hid_device(dev->parent);
84 	struct gt683r_led *led = hid_get_drvdata(hdev);
85 
86 	if (led->mode == GT683R_LED_NORMAL)
87 		sysfs_mode = 0;
88 	else if (led->mode == GT683R_LED_AUDIO)
89 		sysfs_mode = 1;
90 	else
91 		sysfs_mode = 2;
92 
93 	return scnprintf(buf, PAGE_SIZE, "%u\n", sysfs_mode);
94 }
95 
96 static ssize_t mode_store(struct device *dev,
97 				struct device_attribute *attr,
98 				const char *buf, size_t count)
99 {
100 	u8 sysfs_mode;
101 	struct hid_device *hdev = to_hid_device(dev->parent);
102 	struct gt683r_led *led = hid_get_drvdata(hdev);
103 
104 
105 	if (kstrtou8(buf, 10, &sysfs_mode) || sysfs_mode > 2)
106 		return -EINVAL;
107 
108 	mutex_lock(&led->lock);
109 
110 	if (sysfs_mode == 0)
111 		led->mode = GT683R_LED_NORMAL;
112 	else if (sysfs_mode == 1)
113 		led->mode = GT683R_LED_AUDIO;
114 	else
115 		led->mode = GT683R_LED_BREATHING;
116 
117 	mutex_unlock(&led->lock);
118 	schedule_work(&led->work);
119 
120 	return count;
121 }
122 
123 static int gt683r_led_snd_msg(struct gt683r_led *led, u8 *msg)
124 {
125 	int ret;
126 
127 	ret = hid_hw_raw_request(led->hdev, msg[0], msg, GT683R_BUFFER_SIZE,
128 				HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
129 	if (ret != GT683R_BUFFER_SIZE) {
130 		hid_err(led->hdev,
131 			"failed to send set report request: %i\n", ret);
132 		if (ret < 0)
133 			return ret;
134 		return -EIO;
135 	}
136 
137 	return 0;
138 }
139 
140 static int gt683r_leds_set(struct gt683r_led *led, u8 leds)
141 {
142 	int ret;
143 	u8 *buffer;
144 
145 	buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
146 	if (!buffer)
147 		return -ENOMEM;
148 
149 	buffer[0] = 0x01;
150 	buffer[1] = 0x02;
151 	buffer[2] = 0x30;
152 	buffer[3] = leds;
153 	ret = gt683r_led_snd_msg(led, buffer);
154 
155 	kfree(buffer);
156 	return ret;
157 }
158 
159 static int gt683r_mode_set(struct gt683r_led *led, u8 mode)
160 {
161 	int ret;
162 	u8 *buffer;
163 
164 	buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
165 	if (!buffer)
166 		return -ENOMEM;
167 
168 	buffer[0] = 0x01;
169 	buffer[1] = 0x02;
170 	buffer[2] = 0x20;
171 	buffer[3] = mode;
172 	buffer[4] = 0x01;
173 	ret = gt683r_led_snd_msg(led, buffer);
174 
175 	kfree(buffer);
176 	return ret;
177 }
178 
179 static void gt683r_led_work(struct work_struct *work)
180 {
181 	int i;
182 	u8 leds = 0;
183 	u8 mode;
184 	struct gt683r_led *led = container_of(work, struct gt683r_led, work);
185 
186 	mutex_lock(&led->lock);
187 
188 	for (i = 0; i < GT683R_LED_COUNT; i++) {
189 		if (led->brightnesses[i])
190 			leds |= BIT(i);
191 	}
192 
193 	if (gt683r_leds_set(led, leds))
194 		goto fail;
195 
196 	if (leds)
197 		mode = led->mode;
198 	else
199 		mode = GT683R_LED_OFF;
200 
201 	gt683r_mode_set(led, mode);
202 fail:
203 	mutex_unlock(&led->lock);
204 }
205 
206 static DEVICE_ATTR_RW(mode);
207 
208 static struct attribute *gt683r_led_attrs[] = {
209 	&dev_attr_mode.attr,
210 	NULL
211 };
212 
213 static const struct attribute_group gt683r_led_group = {
214 	.name = "gt683r",
215 	.attrs = gt683r_led_attrs,
216 };
217 
218 static const struct attribute_group *gt683r_led_groups[] = {
219 	&gt683r_led_group,
220 	NULL
221 };
222 
223 static int gt683r_led_probe(struct hid_device *hdev,
224 			const struct hid_device_id *id)
225 {
226 	int i;
227 	int ret;
228 	int name_sz;
229 	char *name;
230 	struct gt683r_led *led;
231 
232 	led = devm_kzalloc(&hdev->dev, sizeof(*led), GFP_KERNEL);
233 	if (!led)
234 		return -ENOMEM;
235 
236 	mutex_init(&led->lock);
237 	INIT_WORK(&led->work, gt683r_led_work);
238 
239 	led->mode = GT683R_LED_NORMAL;
240 	led->hdev = hdev;
241 	hid_set_drvdata(hdev, led);
242 
243 	ret = hid_parse(hdev);
244 	if (ret) {
245 		hid_err(hdev, "hid parsing failed\n");
246 		return ret;
247 	}
248 
249 	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
250 	if (ret) {
251 		hid_err(hdev, "hw start failed\n");
252 		return ret;
253 	}
254 
255 	for (i = 0; i < GT683R_LED_COUNT; i++) {
256 		name_sz = strlen(dev_name(&hdev->dev)) +
257 				strlen(gt683r_panel_names[i]) + 3;
258 
259 		name = devm_kzalloc(&hdev->dev, name_sz, GFP_KERNEL);
260 		if (!name) {
261 			ret = -ENOMEM;
262 			goto fail;
263 		}
264 
265 		snprintf(name, name_sz, "%s::%s",
266 				dev_name(&hdev->dev), gt683r_panel_names[i]);
267 		led->led_devs[i].name = name;
268 		led->led_devs[i].max_brightness = 1;
269 		led->led_devs[i].brightness_set = gt683r_brightness_set;
270 		led->led_devs[i].groups = gt683r_led_groups;
271 
272 		ret = led_classdev_register(&hdev->dev, &led->led_devs[i]);
273 		if (ret) {
274 			hid_err(hdev, "could not register led device\n");
275 			goto fail;
276 		}
277 	}
278 
279 	return 0;
280 
281 fail:
282 	for (i = i - 1; i >= 0; i--)
283 		led_classdev_unregister(&led->led_devs[i]);
284 	hid_hw_stop(hdev);
285 	return ret;
286 }
287 
288 static void gt683r_led_remove(struct hid_device *hdev)
289 {
290 	int i;
291 	struct gt683r_led *led = hid_get_drvdata(hdev);
292 
293 	for (i = 0; i < GT683R_LED_COUNT; i++)
294 		led_classdev_unregister(&led->led_devs[i]);
295 	flush_work(&led->work);
296 	hid_hw_stop(hdev);
297 }
298 
299 static struct hid_driver gt683r_led_driver = {
300 	.probe = gt683r_led_probe,
301 	.remove = gt683r_led_remove,
302 	.name = "gt683r_led",
303 	.id_table = gt683r_led_id,
304 };
305 
306 module_hid_driver(gt683r_led_driver);
307 
308 MODULE_AUTHOR("Janne Kanniainen");
309 MODULE_DESCRIPTION("MSI GT683R led driver");
310 MODULE_LICENSE("GPL");
311