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 = 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");