xref: /openbmc/linux/drivers/hid/hid-gt683r.c (revision e8f6f3b4)
1 /*
2  * MSI GT683R led driver
3  *
4  * Copyright (c) 2014 Janne Kanniainen <janne.kanniainen@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 of
9  * the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  */
17 
18 #include <linux/device.h>
19 #include <linux/hid.h>
20 #include <linux/kernel.h>
21 #include <linux/leds.h>
22 #include <linux/module.h>
23 
24 #include "hid-ids.h"
25 
26 #define GT683R_BUFFER_SIZE			8
27 
28 /*
29  * GT683R_LED_OFF: all LEDs are off
30  * GT683R_LED_AUDIO: LEDs brightness depends on sound level
31  * GT683R_LED_BREATHING: LEDs brightness varies at human breathing rate
32  * GT683R_LED_NORMAL: LEDs are fully on when enabled
33  */
34 enum gt683r_led_mode {
35 	GT683R_LED_OFF = 0,
36 	GT683R_LED_AUDIO = 2,
37 	GT683R_LED_BREATHING = 3,
38 	GT683R_LED_NORMAL = 5
39 };
40 
41 enum gt683r_panels {
42 	GT683R_LED_BACK = 0,
43 	GT683R_LED_SIDE = 1,
44 	GT683R_LED_FRONT = 2,
45 	GT683R_LED_COUNT,
46 };
47 
48 static const char * const gt683r_panel_names[] = {
49 	"back",
50 	"side",
51 	"front",
52 };
53 
54 struct gt683r_led {
55 	struct hid_device *hdev;
56 	struct led_classdev led_devs[GT683R_LED_COUNT];
57 	struct mutex lock;
58 	struct work_struct work;
59 	enum led_brightness brightnesses[GT683R_LED_COUNT];
60 	enum gt683r_led_mode mode;
61 };
62 
63 static const struct hid_device_id gt683r_led_id[] = {
64 	{ HID_USB_DEVICE(USB_VENDOR_ID_MSI, USB_DEVICE_ID_MSI_GT683R_LED_PANEL) },
65 	{ }
66 };
67 
68 static void gt683r_brightness_set(struct led_classdev *led_cdev,
69 				enum led_brightness brightness)
70 {
71 	int i;
72 	struct device *dev = led_cdev->dev->parent;
73 	struct hid_device *hdev = container_of(dev, struct hid_device, dev);
74 	struct gt683r_led *led = hid_get_drvdata(hdev);
75 
76 	for (i = 0; i < GT683R_LED_COUNT; i++) {
77 		if (led_cdev == &led->led_devs[i])
78 			break;
79 	}
80 
81 	if (i < GT683R_LED_COUNT) {
82 		led->brightnesses[i] = brightness;
83 		schedule_work(&led->work);
84 	}
85 }
86 
87 static ssize_t mode_show(struct device *dev,
88 				struct device_attribute *attr,
89 				char *buf)
90 {
91 	u8 sysfs_mode;
92 	struct hid_device *hdev = container_of(dev->parent,
93 					struct hid_device, dev);
94 	struct gt683r_led *led = hid_get_drvdata(hdev);
95 
96 	if (led->mode == GT683R_LED_NORMAL)
97 		sysfs_mode = 0;
98 	else if (led->mode == GT683R_LED_AUDIO)
99 		sysfs_mode = 1;
100 	else
101 		sysfs_mode = 2;
102 
103 	return scnprintf(buf, PAGE_SIZE, "%u\n", sysfs_mode);
104 }
105 
106 static ssize_t mode_store(struct device *dev,
107 				struct device_attribute *attr,
108 				const char *buf, size_t count)
109 {
110 	u8 sysfs_mode;
111 	struct hid_device *hdev = container_of(dev->parent,
112 					struct hid_device, dev);
113 	struct gt683r_led *led = hid_get_drvdata(hdev);
114 
115 
116 	if (kstrtou8(buf, 10, &sysfs_mode) || sysfs_mode > 2)
117 		return -EINVAL;
118 
119 	mutex_lock(&led->lock);
120 
121 	if (sysfs_mode == 0)
122 		led->mode = GT683R_LED_NORMAL;
123 	else if (sysfs_mode == 1)
124 		led->mode = GT683R_LED_AUDIO;
125 	else
126 		led->mode = GT683R_LED_BREATHING;
127 
128 	mutex_unlock(&led->lock);
129 	schedule_work(&led->work);
130 
131 	return count;
132 }
133 
134 static int gt683r_led_snd_msg(struct gt683r_led *led, u8 *msg)
135 {
136 	int ret;
137 
138 	ret = hid_hw_raw_request(led->hdev, msg[0], msg, GT683R_BUFFER_SIZE,
139 				HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
140 	if (ret != GT683R_BUFFER_SIZE) {
141 		hid_err(led->hdev,
142 			"failed to send set report request: %i\n", ret);
143 		if (ret < 0)
144 			return ret;
145 		return -EIO;
146 	}
147 
148 	return 0;
149 }
150 
151 static int gt683r_leds_set(struct gt683r_led *led, u8 leds)
152 {
153 	int ret;
154 	u8 *buffer;
155 
156 	buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
157 	if (!buffer)
158 		return -ENOMEM;
159 
160 	buffer[0] = 0x01;
161 	buffer[1] = 0x02;
162 	buffer[2] = 0x30;
163 	buffer[3] = leds;
164 	ret = gt683r_led_snd_msg(led, buffer);
165 
166 	kfree(buffer);
167 	return ret;
168 }
169 
170 static int gt683r_mode_set(struct gt683r_led *led, u8 mode)
171 {
172 	int ret;
173 	u8 *buffer;
174 
175 	buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
176 	if (!buffer)
177 		return -ENOMEM;
178 
179 	buffer[0] = 0x01;
180 	buffer[1] = 0x02;
181 	buffer[2] = 0x20;
182 	buffer[3] = mode;
183 	buffer[4] = 0x01;
184 	ret = gt683r_led_snd_msg(led, buffer);
185 
186 	kfree(buffer);
187 	return ret;
188 }
189 
190 static void gt683r_led_work(struct work_struct *work)
191 {
192 	int i;
193 	u8 leds = 0;
194 	u8 mode;
195 	struct gt683r_led *led = container_of(work, struct gt683r_led, work);
196 
197 	mutex_lock(&led->lock);
198 
199 	for (i = 0; i < GT683R_LED_COUNT; i++) {
200 		if (led->brightnesses[i])
201 			leds |= BIT(i);
202 	}
203 
204 	if (gt683r_leds_set(led, leds))
205 		goto fail;
206 
207 	if (leds)
208 		mode = led->mode;
209 	else
210 		mode = GT683R_LED_OFF;
211 
212 	gt683r_mode_set(led, mode);
213 fail:
214 	mutex_unlock(&led->lock);
215 }
216 
217 static DEVICE_ATTR_RW(mode);
218 
219 static struct attribute *gt683r_led_attrs[] = {
220 	&dev_attr_mode.attr,
221 	NULL
222 };
223 
224 static const struct attribute_group gt683r_led_group = {
225 	.name = "gt683r",
226 	.attrs = gt683r_led_attrs,
227 };
228 
229 static const struct attribute_group *gt683r_led_groups[] = {
230 	&gt683r_led_group,
231 	NULL
232 };
233 
234 static int gt683r_led_probe(struct hid_device *hdev,
235 			const struct hid_device_id *id)
236 {
237 	int i;
238 	int ret;
239 	int name_sz;
240 	char *name;
241 	struct gt683r_led *led;
242 
243 	led = devm_kzalloc(&hdev->dev, sizeof(*led), GFP_KERNEL);
244 	if (!led)
245 		return -ENOMEM;
246 
247 	mutex_init(&led->lock);
248 	INIT_WORK(&led->work, gt683r_led_work);
249 
250 	led->mode = GT683R_LED_NORMAL;
251 	led->hdev = hdev;
252 	hid_set_drvdata(hdev, led);
253 
254 	ret = hid_parse(hdev);
255 	if (ret) {
256 		hid_err(hdev, "hid parsing failed\n");
257 		return ret;
258 	}
259 
260 	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
261 	if (ret) {
262 		hid_err(hdev, "hw start failed\n");
263 		return ret;
264 	}
265 
266 	for (i = 0; i < GT683R_LED_COUNT; i++) {
267 		name_sz = strlen(dev_name(&hdev->dev)) +
268 				strlen(gt683r_panel_names[i]) + 3;
269 
270 		name = devm_kzalloc(&hdev->dev, name_sz, GFP_KERNEL);
271 		if (!name) {
272 			ret = -ENOMEM;
273 			goto fail;
274 		}
275 
276 		snprintf(name, name_sz, "%s::%s",
277 				dev_name(&hdev->dev), gt683r_panel_names[i]);
278 		led->led_devs[i].name = name;
279 		led->led_devs[i].max_brightness = 1;
280 		led->led_devs[i].brightness_set = gt683r_brightness_set;
281 		led->led_devs[i].groups = gt683r_led_groups;
282 
283 		ret = led_classdev_register(&hdev->dev, &led->led_devs[i]);
284 		if (ret) {
285 			hid_err(hdev, "could not register led device\n");
286 			goto fail;
287 		}
288 	}
289 
290 	return 0;
291 
292 fail:
293 	for (i = i - 1; i >= 0; i--)
294 		led_classdev_unregister(&led->led_devs[i]);
295 	hid_hw_stop(hdev);
296 	return ret;
297 }
298 
299 static void gt683r_led_remove(struct hid_device *hdev)
300 {
301 	int i;
302 	struct gt683r_led *led = hid_get_drvdata(hdev);
303 
304 	for (i = 0; i < GT683R_LED_COUNT; i++)
305 		led_classdev_unregister(&led->led_devs[i]);
306 	flush_work(&led->work);
307 	hid_hw_stop(hdev);
308 }
309 
310 static struct hid_driver gt683r_led_driver = {
311 	.probe = gt683r_led_probe,
312 	.remove = gt683r_led_remove,
313 	.name = "gt683r_led",
314 	.id_table = gt683r_led_id,
315 };
316 
317 module_hid_driver(gt683r_led_driver);
318 
319 MODULE_AUTHOR("Janne Kanniainen");
320 MODULE_DESCRIPTION("MSI GT683R led driver");
321 MODULE_LICENSE("GPL");
322