xref: /openbmc/linux/drivers/hid/hid-gt683r.c (revision 1c2dd16a)
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 = to_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 = to_hid_device(dev->parent);
93 	struct gt683r_led *led = hid_get_drvdata(hdev);
94 
95 	if (led->mode == GT683R_LED_NORMAL)
96 		sysfs_mode = 0;
97 	else if (led->mode == GT683R_LED_AUDIO)
98 		sysfs_mode = 1;
99 	else
100 		sysfs_mode = 2;
101 
102 	return scnprintf(buf, PAGE_SIZE, "%u\n", sysfs_mode);
103 }
104 
105 static ssize_t mode_store(struct device *dev,
106 				struct device_attribute *attr,
107 				const char *buf, size_t count)
108 {
109 	u8 sysfs_mode;
110 	struct hid_device *hdev = to_hid_device(dev->parent);
111 	struct gt683r_led *led = hid_get_drvdata(hdev);
112 
113 
114 	if (kstrtou8(buf, 10, &sysfs_mode) || sysfs_mode > 2)
115 		return -EINVAL;
116 
117 	mutex_lock(&led->lock);
118 
119 	if (sysfs_mode == 0)
120 		led->mode = GT683R_LED_NORMAL;
121 	else if (sysfs_mode == 1)
122 		led->mode = GT683R_LED_AUDIO;
123 	else
124 		led->mode = GT683R_LED_BREATHING;
125 
126 	mutex_unlock(&led->lock);
127 	schedule_work(&led->work);
128 
129 	return count;
130 }
131 
132 static int gt683r_led_snd_msg(struct gt683r_led *led, u8 *msg)
133 {
134 	int ret;
135 
136 	ret = hid_hw_raw_request(led->hdev, msg[0], msg, GT683R_BUFFER_SIZE,
137 				HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
138 	if (ret != GT683R_BUFFER_SIZE) {
139 		hid_err(led->hdev,
140 			"failed to send set report request: %i\n", ret);
141 		if (ret < 0)
142 			return ret;
143 		return -EIO;
144 	}
145 
146 	return 0;
147 }
148 
149 static int gt683r_leds_set(struct gt683r_led *led, u8 leds)
150 {
151 	int ret;
152 	u8 *buffer;
153 
154 	buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
155 	if (!buffer)
156 		return -ENOMEM;
157 
158 	buffer[0] = 0x01;
159 	buffer[1] = 0x02;
160 	buffer[2] = 0x30;
161 	buffer[3] = leds;
162 	ret = gt683r_led_snd_msg(led, buffer);
163 
164 	kfree(buffer);
165 	return ret;
166 }
167 
168 static int gt683r_mode_set(struct gt683r_led *led, u8 mode)
169 {
170 	int ret;
171 	u8 *buffer;
172 
173 	buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
174 	if (!buffer)
175 		return -ENOMEM;
176 
177 	buffer[0] = 0x01;
178 	buffer[1] = 0x02;
179 	buffer[2] = 0x20;
180 	buffer[3] = mode;
181 	buffer[4] = 0x01;
182 	ret = gt683r_led_snd_msg(led, buffer);
183 
184 	kfree(buffer);
185 	return ret;
186 }
187 
188 static void gt683r_led_work(struct work_struct *work)
189 {
190 	int i;
191 	u8 leds = 0;
192 	u8 mode;
193 	struct gt683r_led *led = container_of(work, struct gt683r_led, work);
194 
195 	mutex_lock(&led->lock);
196 
197 	for (i = 0; i < GT683R_LED_COUNT; i++) {
198 		if (led->brightnesses[i])
199 			leds |= BIT(i);
200 	}
201 
202 	if (gt683r_leds_set(led, leds))
203 		goto fail;
204 
205 	if (leds)
206 		mode = led->mode;
207 	else
208 		mode = GT683R_LED_OFF;
209 
210 	gt683r_mode_set(led, mode);
211 fail:
212 	mutex_unlock(&led->lock);
213 }
214 
215 static DEVICE_ATTR_RW(mode);
216 
217 static struct attribute *gt683r_led_attrs[] = {
218 	&dev_attr_mode.attr,
219 	NULL
220 };
221 
222 static const struct attribute_group gt683r_led_group = {
223 	.name = "gt683r",
224 	.attrs = gt683r_led_attrs,
225 };
226 
227 static const struct attribute_group *gt683r_led_groups[] = {
228 	&gt683r_led_group,
229 	NULL
230 };
231 
232 static int gt683r_led_probe(struct hid_device *hdev,
233 			const struct hid_device_id *id)
234 {
235 	int i;
236 	int ret;
237 	int name_sz;
238 	char *name;
239 	struct gt683r_led *led;
240 
241 	led = devm_kzalloc(&hdev->dev, sizeof(*led), GFP_KERNEL);
242 	if (!led)
243 		return -ENOMEM;
244 
245 	mutex_init(&led->lock);
246 	INIT_WORK(&led->work, gt683r_led_work);
247 
248 	led->mode = GT683R_LED_NORMAL;
249 	led->hdev = hdev;
250 	hid_set_drvdata(hdev, led);
251 
252 	ret = hid_parse(hdev);
253 	if (ret) {
254 		hid_err(hdev, "hid parsing failed\n");
255 		return ret;
256 	}
257 
258 	ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
259 	if (ret) {
260 		hid_err(hdev, "hw start failed\n");
261 		return ret;
262 	}
263 
264 	for (i = 0; i < GT683R_LED_COUNT; i++) {
265 		name_sz = strlen(dev_name(&hdev->dev)) +
266 				strlen(gt683r_panel_names[i]) + 3;
267 
268 		name = devm_kzalloc(&hdev->dev, name_sz, GFP_KERNEL);
269 		if (!name) {
270 			ret = -ENOMEM;
271 			goto fail;
272 		}
273 
274 		snprintf(name, name_sz, "%s::%s",
275 				dev_name(&hdev->dev), gt683r_panel_names[i]);
276 		led->led_devs[i].name = name;
277 		led->led_devs[i].max_brightness = 1;
278 		led->led_devs[i].brightness_set = gt683r_brightness_set;
279 		led->led_devs[i].groups = gt683r_led_groups;
280 
281 		ret = led_classdev_register(&hdev->dev, &led->led_devs[i]);
282 		if (ret) {
283 			hid_err(hdev, "could not register led device\n");
284 			goto fail;
285 		}
286 	}
287 
288 	return 0;
289 
290 fail:
291 	for (i = i - 1; i >= 0; i--)
292 		led_classdev_unregister(&led->led_devs[i]);
293 	hid_hw_stop(hdev);
294 	return ret;
295 }
296 
297 static void gt683r_led_remove(struct hid_device *hdev)
298 {
299 	int i;
300 	struct gt683r_led *led = hid_get_drvdata(hdev);
301 
302 	for (i = 0; i < GT683R_LED_COUNT; i++)
303 		led_classdev_unregister(&led->led_devs[i]);
304 	flush_work(&led->work);
305 	hid_hw_stop(hdev);
306 }
307 
308 static struct hid_driver gt683r_led_driver = {
309 	.probe = gt683r_led_probe,
310 	.remove = gt683r_led_remove,
311 	.name = "gt683r_led",
312 	.id_table = gt683r_led_id,
313 };
314 
315 module_hid_driver(gt683r_led_driver);
316 
317 MODULE_AUTHOR("Janne Kanniainen");
318 MODULE_DESCRIPTION("MSI GT683R led driver");
319 MODULE_LICENSE("GPL");
320