drivers/hid/hid-gt683r.c

   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");