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 MODULE_DEVICE_TABLE(hid, gt683r_led_id);
  68
  69 static void gt683r_brightness_set(struct led_classdev *led_cdev,
  70                                 enum led_brightness brightness)
  71 {
  72         int i;
  73         struct device *dev = led_cdev->dev->parent;
  74         struct hid_device *hdev = to_hid_device(dev);
  75         struct gt683r_led *led = hid_get_drvdata(hdev);
  76
  77         for (i = 0; i < GT683R_LED_COUNT; i++) {
  78                 if (led_cdev == &led->led_devs[i])
  79                         break;
  80         }
  81
  82         if (i < GT683R_LED_COUNT) {
  83                 led->brightnesses[i] = brightness;
  84                 schedule_work(&led->work);
  85         }
  86 }
  87
  88 static ssize_t mode_show(struct device *dev,
  89                                 struct device_attribute *attr,
  90                                 char *buf)
  91 {
  92         u8 sysfs_mode;
  93         struct hid_device *hdev = to_hid_device(dev->parent);
  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 = to_hid_device(dev->parent);
 112         struct gt683r_led *led = hid_get_drvdata(hdev);
 113
 114
 115         if (kstrtou8(buf, 10, &sysfs_mode) || sysfs_mode > 2)
 116                 return -EINVAL;
 117
 118         mutex_lock(&led->lock);
 119
 120         if (sysfs_mode == 0)
 121                 led->mode = GT683R_LED_NORMAL;
 122         else if (sysfs_mode == 1)
 123                 led->mode = GT683R_LED_AUDIO;
 124         else
 125                 led->mode = GT683R_LED_BREATHING;
 126
 127         mutex_unlock(&led->lock);
 128         schedule_work(&led->work);
 129
 130         return count;
 131 }
 132
 133 static int gt683r_led_snd_msg(struct gt683r_led *led, u8 *msg)
 134 {
 135         int ret;
 136
 137         ret = hid_hw_raw_request(led->hdev, msg[0], msg, GT683R_BUFFER_SIZE,
 138                                 HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
 139         if (ret != GT683R_BUFFER_SIZE) {
 140                 hid_err(led->hdev,
 141                         "failed to send set report request: %i\n", ret);
 142                 if (ret < 0)
 143                         return ret;
 144                 return -EIO;
 145         }
 146
 147         return 0;
 148 }
 149
 150 static int gt683r_leds_set(struct gt683r_led *led, u8 leds)
 151 {
 152         int ret;
 153         u8 *buffer;
 154
 155         buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
 156         if (!buffer)
 157                 return -ENOMEM;
 158
 159         buffer[0] = 0x01;
 160         buffer[1] = 0x02;
 161         buffer[2] = 0x30;
 162         buffer[3] = leds;
 163         ret = gt683r_led_snd_msg(led, buffer);
 164
 165         kfree(buffer);
 166         return ret;
 167 }
 168
 169 static int gt683r_mode_set(struct gt683r_led *led, u8 mode)
 170 {
 171         int ret;
 172         u8 *buffer;
 173
 174         buffer = kzalloc(GT683R_BUFFER_SIZE, GFP_KERNEL);
 175         if (!buffer)
 176                 return -ENOMEM;
 177
 178         buffer[0] = 0x01;
 179         buffer[1] = 0x02;
 180         buffer[2] = 0x20;
 181         buffer[3] = mode;
 182         buffer[4] = 0x01;
 183         ret = gt683r_led_snd_msg(led, buffer);
 184
 185         kfree(buffer);
 186         return ret;
 187 }
 188
 189 static void gt683r_led_work(struct work_struct *work)
 190 {
 191         int i;
 192         u8 leds = 0;
 193         u8 mode;
 194         struct gt683r_led *led = container_of(work, struct gt683r_led, work);
 195
 196         mutex_lock(&led->lock);
 197
 198         for (i = 0; i < GT683R_LED_COUNT; i++) {
 199                 if (led->brightnesses[i])
 200                         leds |= BIT(i);
 201         }
 202
 203         if (gt683r_leds_set(led, leds))
 204                 goto fail;
 205
 206         if (leds)
 207                 mode = led->mode;
 208         else
 209                 mode = GT683R_LED_OFF;
 210
 211         gt683r_mode_set(led, mode);
 212 fail:
 213         mutex_unlock(&led->lock);
 214 }
 215
 216 static DEVICE_ATTR_RW(mode);
 217
 218 static struct attribute *gt683r_led_attrs[] = {
 219         &dev_attr_mode.attr,
 220         NULL
 221 };
 222
 223 static const struct attribute_group gt683r_led_group = {
 224         .name = "gt683r",
 225         .attrs = gt683r_led_attrs,
 226 };
 227
 228 static const struct attribute_group *gt683r_led_groups[] = {
 229         &gt683r_led_group,
 230         NULL
 231 };
 232
 233 static int gt683r_led_probe(struct hid_device *hdev,
 234                         const struct hid_device_id *id)
 235 {
 236         int i;
 237         int ret;
 238         int name_sz;
 239         char *name;
 240         struct gt683r_led *led;
 241
 242         led = devm_kzalloc(&hdev->dev, sizeof(*led), GFP_KERNEL);
 243         if (!led)
 244                 return -ENOMEM;
 245
 246         mutex_init(&led->lock);
 247         INIT_WORK(&led->work, gt683r_led_work);
 248
 249         led->mode = GT683R_LED_NORMAL;
 250         led->hdev = hdev;
 251         hid_set_drvdata(hdev, led);
 252
 253         ret = hid_parse(hdev);
 254         if (ret) {
 255                 hid_err(hdev, "hid parsing failed\n");
 256                 return ret;
 257         }
 258
 259         ret = hid_hw_start(hdev, HID_CONNECT_HIDRAW);
 260         if (ret) {
 261                 hid_err(hdev, "hw start failed\n");
 262                 return ret;
 263         }
 264
 265         for (i = 0; i < GT683R_LED_COUNT; i++) {
 266                 name_sz = strlen(dev_name(&hdev->dev)) +
 267                                 strlen(gt683r_panel_names[i]) + 3;
 268
 269                 name = devm_kzalloc(&hdev->dev, name_sz, GFP_KERNEL);
 270                 if (!name) {
 271                         ret = -ENOMEM;
 272                         goto fail;
 273                 }
 274
 275                 snprintf(name, name_sz, "%s::%s",
 276                                 dev_name(&hdev->dev), gt683r_panel_names[i]);
 277                 led->led_devs[i].name = name;
 278                 led->led_devs[i].max_brightness = 1;
 279                 led->led_devs[i].brightness_set = gt683r_brightness_set;
 280                 led->led_devs[i].groups = gt683r_led_groups;
 281
 282                 ret = led_classdev_register(&hdev->dev, &led->led_devs[i]);
 283                 if (ret) {
 284                         hid_err(hdev, "could not register led device\n");
 285                         goto fail;
 286                 }
 287         }
 288
 289         return 0;
 290
 291 fail:
 292         for (i = i - 1; i >= 0; i--)
 293                 led_classdev_unregister(&led->led_devs[i]);
 294         hid_hw_stop(hdev);
 295         return ret;
 296 }
 297
 298 static void gt683r_led_remove(struct hid_device *hdev)
 299 {
 300         int i;
 301         struct gt683r_led *led = hid_get_drvdata(hdev);
 302
 303         for (i = 0; i < GT683R_LED_COUNT; i++)
 304                 led_classdev_unregister(&led->led_devs[i]);
 305         flush_work(&led->work);
 306         hid_hw_stop(hdev);
 307 }
 308
 309 static struct hid_driver gt683r_led_driver = {
 310         .probe = gt683r_led_probe,
 311         .remove = gt683r_led_remove,
 312         .name = "gt683r_led",
 313         .id_table = gt683r_led_id,
 314 };
 315
 316 module_hid_driver(gt683r_led_driver);
 317
 318 MODULE_AUTHOR("Janne Kanniainen");
 319 MODULE_DESCRIPTION("MSI GT683R led driver");
 320 MODULE_LICENSE("GPL");