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