hid-gt683r.c

  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 */
 24enum 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
 31enum gt683r_panels {
 32	GT683R_LED_BACK = 0,
 33	GT683R_LED_SIDE = 1,
 34	GT683R_LED_FRONT = 2,
 35	GT683R_LED_COUNT,
 36};
 37
 38static const char * const gt683r_panel_names[] = {
 39	"back",
 40	"side",
 41	"front",
 42};
 43
 44struct 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
 53static 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};
 57MODULE_DEVICE_TABLE(hid, gt683r_led_id);
 58
 59static 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
 78static 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
 96static 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
123static 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
140static 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
159static 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
179static 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);
202fail:
203	mutex_unlock(&led->lock);
204}
205
206static DEVICE_ATTR_RW(mode);
207
208static struct attribute *gt683r_led_attrs[] = {
209	&dev_attr_mode.attr,
210	NULL
211};
212
213static const struct attribute_group gt683r_led_group = {
214	.name = "gt683r",
215	.attrs = gt683r_led_attrs,
216};
217
218static const struct attribute_group *gt683r_led_groups[] = {
219	&gt683r_led_group,
220	NULL
221};
222
223static 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
281fail:
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
288static 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
299static 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
306module_hid_driver(gt683r_led_driver);
307
308MODULE_AUTHOR("Janne Kanniainen");
309MODULE_DESCRIPTION("MSI GT683R led driver");
310MODULE_LICENSE("GPL");