drivers/hid/hid-cmedia.c

   1 /*
   2  * HID driver for CMedia CM6533 audio jack controls
   3  *
   4  * Copyright (C) 2015 Ben Chen <[email protected]>
   5  *
   6  * This software is licensed under the terms of the GNU General Public
   7  * License version 2, as published by the Free Software Foundation, and
   8  * may be copied, distributed, and modified under those terms.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  */
  15
  16 #include <linux/device.h>
  17 #include <linux/hid.h>
  18 #include <linux/module.h>
  19 #include "hid-ids.h"
  20
  21 MODULE_AUTHOR("Ben Chen");
  22 MODULE_DESCRIPTION("CM6533 HID jack controls");
  23 MODULE_LICENSE("GPL");
  24
  25 #define CM6533_JD_TYPE_COUNT      1
  26 #define CM6533_JD_RAWEV_LEN      16
  27 #define CM6533_JD_SFX_OFFSET      8
  28
  29 /*
  30 *
  31 *CM6533 audio jack HID raw events:
  32 *
  33 *Plug in:
  34 *01000600 002083xx 080008c0 10000000
  35 *about 3 seconds later...
  36 *01000a00 002083xx 08000380 10000000
  37 *01000600 002083xx 08000380 10000000
  38 *
  39 *Plug out:
  40 *01000400 002083xx 080008c0 x0000000
  41 */
  42
  43 static const u8 ji_sfx[] = { 0x08, 0x00, 0x08, 0xc0 };
  44 static const u8 ji_in[]  = { 0x01, 0x00, 0x06, 0x00 };
  45 static const u8 ji_out[] = { 0x01, 0x00, 0x04, 0x00 };
  46
  47 static int jack_switch_types[CM6533_JD_TYPE_COUNT] = {
  48         SW_HEADPHONE_INSERT,
  49 };
  50
  51 struct cmhid {
  52         struct input_dev *input_dev;
  53         struct hid_device *hid;
  54         unsigned short switch_map[CM6533_JD_TYPE_COUNT];
  55 };
  56
  57 static void hp_ev(struct hid_device *hid, struct cmhid *cm, int value)
  58 {
  59         input_report_switch(cm->input_dev, SW_HEADPHONE_INSERT, value);
  60         input_sync(cm->input_dev);
  61 }
  62
  63 static int cmhid_raw_event(struct hid_device *hid, struct hid_report *report,
  64          u8 *data, int len)
  65 {
  66         struct cmhid *cm = hid_get_drvdata(hid);
  67
  68         if (len != CM6533_JD_RAWEV_LEN)
  69                 goto out;
  70         if (memcmp(data+CM6533_JD_SFX_OFFSET, ji_sfx, sizeof(ji_sfx)))
  71                 goto out;
  72
  73         if (!memcmp(data, ji_out, sizeof(ji_out))) {
  74                 hp_ev(hid, cm, 0);
  75                 goto out;
  76         }
  77         if (!memcmp(data, ji_in, sizeof(ji_in))) {
  78                 hp_ev(hid, cm, 1);
  79                 goto out;
  80         }
  81
  82 out:
  83         return 0;
  84 }
  85
  86 static int cmhid_input_configured(struct hid_device *hid,
  87                 struct hid_input *hidinput)
  88 {
  89         struct input_dev *input_dev = hidinput->input;
  90         struct cmhid *cm = hid_get_drvdata(hid);
  91         int i;
  92
  93         cm->input_dev = input_dev;
  94         memcpy(cm->switch_map, jack_switch_types, sizeof(cm->switch_map));
  95         input_dev->evbit[0] = BIT(EV_SW);
  96         for (i = 0; i < CM6533_JD_TYPE_COUNT; i++)
  97                 input_set_capability(cm->input_dev,
  98                                 EV_SW, jack_switch_types[i]);
  99         return 0;
 100 }
 101
 102 static int cmhid_input_mapping(struct hid_device *hid,
 103                 struct hid_input *hi, struct hid_field *field,
 104                 struct hid_usage *usage, unsigned long **bit, int *max)
 105 {
 106         return -1;
 107 }
 108
 109 static int cmhid_probe(struct hid_device *hid, const struct hid_device_id *id)
 110 {
 111         int ret;
 112         struct cmhid *cm;
 113
 114         cm = kzalloc(sizeof(struct cmhid), GFP_KERNEL);
 115         if (!cm) {
 116                 ret = -ENOMEM;
 117                 goto allocfail;
 118         }
 119
 120         cm->hid = hid;
 121
 122         hid->quirks |= HID_QUIRK_HIDINPUT_FORCE;
 123         hid_set_drvdata(hid, cm);
 124
 125         ret = hid_parse(hid);
 126         if (ret) {
 127                 hid_err(hid, "parse failed\n");
 128                 goto fail;
 129         }
 130
 131         ret = hid_hw_start(hid, HID_CONNECT_DEFAULT | HID_CONNECT_HIDDEV_FORCE);
 132         if (ret) {
 133                 hid_err(hid, "hw start failed\n");
 134                 goto fail;
 135         }
 136
 137         return 0;
 138 fail:
 139         kfree(cm);
 140 allocfail:
 141         return ret;
 142 }
 143
 144 static void cmhid_remove(struct hid_device *hid)
 145 {
 146         struct cmhid *cm = hid_get_drvdata(hid);
 147
 148         hid_hw_stop(hid);
 149         kfree(cm);
 150 }
 151
 152 static const struct hid_device_id cmhid_devices[] = {
 153         { HID_USB_DEVICE(USB_VENDOR_ID_CMEDIA, USB_DEVICE_ID_CM6533) },
 154         { }
 155 };
 156 MODULE_DEVICE_TABLE(hid, cmhid_devices);
 157
 158 static struct hid_driver cmhid_driver = {
 159         .name = "cm6533_jd",
 160         .id_table = cmhid_devices,
 161         .raw_event = cmhid_raw_event,
 162         .input_configured = cmhid_input_configured,
 163         .probe = cmhid_probe,
 164         .remove = cmhid_remove,
 165         .input_mapping = cmhid_input_mapping,
 166 };
 167 module_hid_driver(cmhid_driver);
 168