--- /dev/null
+/*
+ * MSI GT683R led driver
+ *
+ * Copyright (c) 2014 Janne Kanniainen <janne.kanniainen@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/device.h>
+#include <linux/hid.h>
+#include <linux/kernel.h>
+#include <linux/leds.h>
+#include <linux/module.h>
+
+#include "hid-ids.h"
+
+#define GT683R_BUFFER_SIZE 8
+
+/*
+ * GT683R_LED_OFF: all LEDs are off
+ * GT683R_LED_AUDIO: LEDs brightness depends on sound level
+ * GT683R_LED_BREATHING: LEDs brightness varies at human breathing rate
+ * GT683R_LED_NORMAL: LEDs are fully on when enabled
+ */
+enum gt683r_led_mode {
+ GT683R_LED_OFF = 0,
+ GT683R_LED_AUDIO = 2,
+ GT683R_LED_BREATHING = 3,
+ GT683R_LED_NORMAL = 5
+};
+
+enum gt683r_panels {
+ GT683R_LED_BACK = 0,
+ GT683R_LED_SIDE = 1,
+ GT683R_LED_FRONT = 2,
+ GT683R_LED_COUNT,
+};
+
+static const char * const gt683r_panel_names[] = {
+ "back",
+ "side",
+ "front",
+};
+
+struct gt683r_led {
+ struct hid_device *hdev;
+ struct led_classdev led_devs[GT683R_LED_COUNT];
+ struct mutex lock;
+ struct work_struct work;
+ enum led_brightness brightnesses[GT683R_LED_COUNT];
+ enum gt683r_led_mode mode;
+};
+
+static const struct hid_device_id gt683r_led_id[] = {
+ { HID_USB_DEVICE(USB_VENDOR_ID_MSI, USB_DEVICE_ID_MSI_GT683R_LED_PANEL) },
+ { }
+};
+
+static void gt683r_brightness_set(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ int i;
+ struct device *dev = led_cdev->dev->parent;
+ struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+ struct gt683r_led *led = hid_get_drvdata(hdev);
+
+ for (i = 0; i < GT683R_LED_COUNT; i++) {
+ if (led_cdev == &led->led_devs[i])
+ break;
+ }
+
+ if (i < GT683R_LED_COUNT) {
+ led->brightnesses[i] = brightness;
+ schedule_work(&led->work);
+ }
+}
+
+static ssize_t leds_mode_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ u8 sysfs_mode;
+ struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+ struct gt683r_led *led = hid_get_drvdata(hdev);
+
+ if (led->mode == GT683R_LED_NORMAL)
+ sysfs_mode = 0;
+ else if (led->mode == GT683R_LED_AUDIO)
+ sysfs_mode = 1;
+ else
+ sysfs_mode = 2;
+
+ return scnprintf(buf, PAGE_SIZE, "%u\n", sysfs_mode);
+}
+
+static ssize_t leds_mode_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ u8 sysfs_mode;
+ struct hid_device *hdev = container_of(dev, struct hid_device, dev);
+ struct gt683r_led *led = hid_get_drvdata(hdev);
+
+
+ if (kstrtou8(buf, 10, &sysfs_mode) || sysfs_mode > 2)
+ return -EINVAL;
+
+ mutex_lock(&led->lock);
+
+ if (sysfs_mode == 0)
+ led->mode = GT683R_LED_NORMAL;
+ else if (sysfs_mode == 1)
+ led->mode = GT683R_LED_AUDIO;
+ else
+ led->mode = GT683R_LED_BREATHING;
+
+ mutex_unlock(&led->lock);
+ schedule_work(&led->work);
+
+ return count;
+}
+
+static int gt683r_led_snd_msg(struct gt683r_led *led, u8 *msg)
+{
+ int ret;
+
+ ret = hid_hw_raw_request(led->hdev, msg[0], msg, GT683R_BUFFER_SIZE,
+ HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
+ if (ret != GT683R_BUFFER_SIZE) {
+ hid_err(led->hdev,
+ "failed to send set report request: %i\n", ret);
+ if (ret < 0)
+ return ret;
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int gt683r_leds_set(struct gt683r_led *led, u8 leds)
+{
+ int ret;
+ u8 *buffer;
+
+ buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+
+ buffer[0] = 0x01;
+ buffer[1] = 0x02;
+ buffer[2] = 0x30;
+ buffer[3] = leds;
+ ret = gt683r_led_snd_msg(led, buffer);
+
+ kfree(buffer);
+ return ret;
+}
+
+static int gt683r_mode_set(struct gt683r_led *led, u8 mode)
+{
+ int ret;
+ u8 *buffer;
+
+ buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+
+ buffer[0] = 0x01;
+ buffer[1] = 0x02;
+ buffer[2] = 0x20;
+ buffer[3] = mode;
+ buffer[4] = 0x01;
+ ret = gt683r_led_snd_msg(led, buffer);
+
+ kfree(buffer);
+ return ret;
+}
+
+static void gt683r_led_work(struct work_struct *work)
+{
+ int i;
+ u8 leds = 0;
+ u8 mode;
+ struct gt683r_led *led = container_of(work, struct gt683r_led, work);
+
+ mutex_lock(&led->lock);
+
+ for (i = 0; i < GT683R_LED_COUNT; i++) {
+ if (led->brightnesses[i])
+ leds |= BIT(i);
+ }
+
+ if (gt683r_leds_set(led, leds))
+ goto fail;
+
+ if (leds)
+ mode = led->mode;
+ else
+ mode = GT683R_LED_OFF;
+
+ gt683r_mode_set(led, mode);
+fail:
+ mutex_unlock(&led->lock);
+}
+
+static DEVICE_ATTR_RW(leds_mode);
+
+static int gt683r_led_probe(struct hid_device *hdev,
+ const struct hid_device_id *id)
+{
+ int i;
+ int ret;
+ int name_sz;
+ char *name;
+ struct gt683r_led *led;
+
+ led = devm_kzalloc(&hdev->dev, sizeof(*led), GFP_KERNEL);
+ if (!led)
+ return -ENOMEM;
+
+ led->mode = GT683R_LED_NORMAL;
+ led->hdev = hdev;
+ hid_set_drvdata(hdev, led);
+
+ ret = hid_parse(hdev);
+ if (ret) {
+ hid_err(hdev, "hid parsing failed\n");
+ return ret;
+ }
+
+ ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
+ if (ret) {
+ hid_err(hdev, "hw start failed\n");
+ return ret;
+ }
+
+ for (i = 0; i < GT683R_LED_COUNT; i++) {
+ name_sz = strlen(dev_name(&hdev->dev)) +
+ strlen(gt683r_panel_names[i]) + 3;
+
+ name = devm_kzalloc(&hdev->dev, name_sz, GFP_KERNEL);
+ if (!name) {
+ ret = -ENOMEM;
+ goto fail;
+ }
+
+ snprintf(name, name_sz, "%s::%s",
+ dev_name(&hdev->dev), gt683r_panel_names[i]);
+ led->led_devs[i].name = name;
+ led->led_devs[i].max_brightness = 1;
+ led->led_devs[i].brightness_set = gt683r_brightness_set;
+ ret = led_classdev_register(&hdev->dev, &led->led_devs[i]);
+ if (ret) {
+ hid_err(hdev, "could not register led device\n");
+ goto fail;
+ }
+ }
+
+ ret = device_create_file(&led->hdev->dev, &dev_attr_leds_mode);
+ if (ret) {
+ hid_err(hdev, "could not make mode attribute file\n");
+ goto fail;
+ }
+
+ mutex_init(&led->lock);
+ INIT_WORK(&led->work, gt683r_led_work);
+
+ return 0;
+
+fail:
+ for (i = i - 1; i >= 0; i--)
+ led_classdev_unregister(&led->led_devs[i]);
+ hid_hw_stop(hdev);
+ return ret;
+}
+
+static void gt683r_led_remove(struct hid_device *hdev)
+{
+ int i;
+ struct gt683r_led *led = hid_get_drvdata(hdev);
+
+ device_remove_file(&hdev->dev, &dev_attr_leds_mode);
+ for (i = 0; i < GT683R_LED_COUNT; i++)
+ led_classdev_unregister(&led->led_devs[i]);
+ flush_work(&led->work);
+ hid_hw_stop(hdev);
+}
+
+static struct hid_driver gt683r_led_driver = {
+ .probe = gt683r_led_probe,
+ .remove = gt683r_led_remove,
+ .name = "gt683r_led",
+ .id_table = gt683r_led_id,
+};
+
+module_hid_driver(gt683r_led_driver);
+
+MODULE_AUTHOR("Janne Kanniainen");
+MODULE_DESCRIPTION("MSI GT683R led driver");
+MODULE_LICENSE("GPL");