drivers/hid/hid-gfrm.c

   1 /*
   2  * HID driver for Google Fiber TV Box remote controls
   3  *
   4  * Copyright (c) 2014-2015 Google Inc.
   5  *
   6  * Author: Petri Gynther <pgynther@google.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the Free
  10  * Software Foundation; either version 2 of the License, or (at your option)
  11  * any later version.
  12  */
  13 #include <linux/device.h>
  14 #include <linux/hid.h>
  15 #include <linux/input.h>
  16 #include <linux/module.h>
  17
  18 #include "hid-ids.h"
  19
  20 #define GFRM100  1  /* Google Fiber GFRM100 (Bluetooth classic) */
  21 #define GFRM200  2  /* Google Fiber GFRM200 (Bluetooth LE) */
  22
  23 #define GFRM100_SEARCH_KEY_REPORT_ID   0xF7
  24 #define GFRM100_SEARCH_KEY_DOWN        0x0
  25 #define GFRM100_SEARCH_KEY_AUDIO_DATA  0x1
  26 #define GFRM100_SEARCH_KEY_UP          0x2
  27
  28 static u8 search_key_dn[3] = {0x40, 0x21, 0x02};
  29 static u8 search_key_up[3] = {0x40, 0x00, 0x00};
  30
  31 static int gfrm_input_mapping(struct hid_device *hdev, struct hid_input *hi,
  32                 struct hid_field *field, struct hid_usage *usage,
  33                 unsigned long **bit, int *max)
  34 {
  35         unsigned long hdev_type = (unsigned long) hid_get_drvdata(hdev);
  36
  37         if (hdev_type == GFRM100) {
  38                 if (usage->hid == (HID_UP_CONSUMER | 0x4)) {
  39                         /* Consumer.0004 -> KEY_INFO */
  40                         hid_map_usage_clear(hi, usage, bit, max, EV_KEY, KEY_INFO);
  41                         return 1;
  42                 }
  43
  44                 if (usage->hid == (HID_UP_CONSUMER | 0x41)) {
  45                         /* Consumer.0041 -> KEY_OK */
  46                         hid_map_usage_clear(hi, usage, bit, max, EV_KEY, KEY_OK);
  47                         return 1;
  48                 }
  49         }
  50
  51         return 0;
  52 }
  53
  54 static int gfrm_raw_event(struct hid_device *hdev, struct hid_report *report,
  55                 u8 *data, int size)
  56 {
  57         unsigned long hdev_type = (unsigned long) hid_get_drvdata(hdev);
  58         int ret = 0;
  59
  60         if (hdev_type != GFRM100)
  61                 return 0;
  62
  63         if (size < 2 || data[0] != GFRM100_SEARCH_KEY_REPORT_ID)
  64                 return 0;
  65
  66         /*
  67          * Convert GFRM100 Search key reports into Consumer.0221 (Key.Search)
  68          * reports. Ignore audio data.
  69          */
  70         switch (data[1]) {
  71         case GFRM100_SEARCH_KEY_DOWN:
  72                 ret = hid_report_raw_event(hdev, HID_INPUT_REPORT, search_key_dn,
  73                                            sizeof(search_key_dn), 1);
  74                 break;
  75
  76         case GFRM100_SEARCH_KEY_AUDIO_DATA:
  77                 break;
  78
  79         case GFRM100_SEARCH_KEY_UP:
  80                 ret = hid_report_raw_event(hdev, HID_INPUT_REPORT, search_key_up,
  81                                            sizeof(search_key_up), 1);
  82                 break;
  83
  84         default:
  85                 break;
  86         }
  87
  88         return (ret < 0) ? ret : -1;
  89 }
  90
  91 static int gfrm_input_configured(struct hid_device *hid, struct hid_input *hidinput)
  92 {
  93         /*
  94          * Enable software autorepeat with:
  95          * - repeat delay: 400 msec
  96          * - repeat period: 100 msec
  97          */
  98         input_enable_softrepeat(hidinput->input, 400, 100);
  99         return 0;
 100 }
 101
 102 static int gfrm_probe(struct hid_device *hdev, const struct hid_device_id *id)
 103 {
 104         int ret;
 105
 106         hid_set_drvdata(hdev, (void *) id->driver_data);
 107
 108         ret = hid_parse(hdev);
 109         if (ret)
 110                 goto done;
 111
 112         if (id->driver_data == GFRM100) {
 113                 /*
 114                  * GFRM100 HID Report Descriptor does not describe the Search
 115                  * key reports. Thus, we need to add it manually here, so that
 116                  * those reports reach gfrm_raw_event() from hid_input_report().
 117                  */
 118                 if (!hid_register_report(hdev, HID_INPUT_REPORT,
 119                                          GFRM100_SEARCH_KEY_REPORT_ID, 0)) {
 120                         ret = -ENOMEM;
 121                         goto done;
 122                 }
 123         }
 124
 125         ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 126 done:
 127         return ret;
 128 }
 129
 130 static void gfrm_remove(struct hid_device *hdev)
 131 {
 132         hid_hw_stop(hdev);
 133         hid_set_drvdata(hdev, NULL);
 134 }
 135
 136 static const struct hid_device_id gfrm_devices[] = {
 137         { HID_BLUETOOTH_DEVICE(0x58, 0x2000),
 138                 .driver_data = GFRM100 },
 139         { HID_BLUETOOTH_DEVICE(0x471, 0x2210),
 140                 .driver_data = GFRM200 },
 141         { }
 142 };
 143 MODULE_DEVICE_TABLE(hid, gfrm_devices);
 144
 145 static struct hid_driver gfrm_driver = {
 146         .name = "gfrm",
 147         .id_table = gfrm_devices,
 148         .probe = gfrm_probe,
 149         .remove = gfrm_remove,
 150         .input_mapping = gfrm_input_mapping,
 151         .raw_event = gfrm_raw_event,
 152         .input_configured = gfrm_input_configured,
 153 };
 154
 155 module_hid_driver(gfrm_driver);
 156
 157 MODULE_AUTHOR("Petri Gynther <pgynther@google.com>");
 158 MODULE_DESCRIPTION("Google Fiber TV Box remote control driver");
 159 MODULE_LICENSE("GPL");