root/drivers/hid/hid-a4tech.c

DEFINITIONS

1. a4_input_mapping
2. a4_input_mapped
3. a4_event
4. a4_probe

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  HID driver for some a4tech "special" devices
   4  *
   5  *  Copyright (c) 1999 Andreas Gal
   6  *  Copyright (c) 2000-2005 Vojtech Pavlik <vojtech@suse.cz>
   7  *  Copyright (c) 2005 Michael Haboustak <mike-@cinci.rr.com> for Concept2, Inc
   8  *  Copyright (c) 2006-2007 Jiri Kosina
   9  *  Copyright (c) 2008 Jiri Slaby
  10  */
  11 
  12 /*
  13  */
  14 
  15 #include <linux/device.h>
  16 #include <linux/input.h>
  17 #include <linux/hid.h>
  18 #include <linux/module.h>
  19 #include <linux/slab.h>
  20 
  21 #include "hid-ids.h"
  22 
  23 #define A4_2WHEEL_MOUSE_HACK_7  0x01
  24 #define A4_2WHEEL_MOUSE_HACK_B8 0x02
  25 
  26 #define A4_WHEEL_ORIENTATION    (HID_UP_GENDESK | 0x000000b8)
  27 
  28 struct a4tech_sc {
  29         unsigned long quirks;
  30         unsigned int hw_wheel;
  31         __s32 delayed_value;
  32 };
  33 
  34 static int a4_input_mapping(struct hid_device *hdev, struct hid_input *hi,
  35                             struct hid_field *field, struct hid_usage *usage,
  36                             unsigned long **bit, int *max)
  37 {
  38         struct a4tech_sc *a4 = hid_get_drvdata(hdev);
  39 
  40         if (a4->quirks & A4_2WHEEL_MOUSE_HACK_B8 &&
  41             usage->hid == A4_WHEEL_ORIENTATION) {
  42                 /*
  43                  * We do not want to have this usage mapped to anything as it's
  44                  * nonstandard and doesn't really behave like an HID report.
  45                  * It's only selecting the orientation (vertical/horizontal) of
  46                  * the previous mouse wheel report. The input_events will be
  47                  * generated once both reports are recorded in a4_event().
  48                  */
  49                 return -1;
  50         }
  51 
  52         return 0;
  53 
  54 }
  55 
  56 static int a4_input_mapped(struct hid_device *hdev, struct hid_input *hi,
  57                 struct hid_field *field, struct hid_usage *usage,
  58                 unsigned long **bit, int *max)
  59 {
  60         struct a4tech_sc *a4 = hid_get_drvdata(hdev);
  61 
  62         if (usage->type == EV_REL && usage->code == REL_WHEEL_HI_RES) {
  63                 set_bit(REL_HWHEEL, *bit);
  64                 set_bit(REL_HWHEEL_HI_RES, *bit);
  65         }
  66 
  67         if ((a4->quirks & A4_2WHEEL_MOUSE_HACK_7) && usage->hid == 0x00090007)
  68                 return -1;
  69 
  70         return 0;
  71 }
  72 
  73 static int a4_event(struct hid_device *hdev, struct hid_field *field,
  74                 struct hid_usage *usage, __s32 value)
  75 {
  76         struct a4tech_sc *a4 = hid_get_drvdata(hdev);
  77         struct input_dev *input;
  78 
  79         if (!(hdev->claimed & HID_CLAIMED_INPUT) || !field->hidinput)
  80                 return 0;
  81 
  82         input = field->hidinput->input;
  83 
  84         if (a4->quirks & A4_2WHEEL_MOUSE_HACK_B8) {
  85                 if (usage->type == EV_REL && usage->code == REL_WHEEL_HI_RES) {
  86                         a4->delayed_value = value;
  87                         return 1;
  88                 }
  89 
  90                 if (usage->hid == A4_WHEEL_ORIENTATION) {
  91                         input_event(input, EV_REL, value ? REL_HWHEEL :
  92                                         REL_WHEEL, a4->delayed_value);
  93                         input_event(input, EV_REL, value ? REL_HWHEEL_HI_RES :
  94                                         REL_WHEEL_HI_RES, a4->delayed_value * 120);
  95                         return 1;
  96                 }
  97         }
  98 
  99         if ((a4->quirks & A4_2WHEEL_MOUSE_HACK_7) && usage->hid == 0x00090007) {
 100                 a4->hw_wheel = !!value;
 101                 return 1;
 102         }
 103 
 104         if (usage->code == REL_WHEEL_HI_RES && a4->hw_wheel) {
 105                 input_event(input, usage->type, REL_HWHEEL, value);
 106                 input_event(input, usage->type, REL_HWHEEL_HI_RES, value * 120);
 107                 return 1;
 108         }
 109 
 110         return 0;
 111 }
 112 
 113 static int a4_probe(struct hid_device *hdev, const struct hid_device_id *id)
 114 {
 115         struct a4tech_sc *a4;
 116         int ret;
 117 
 118         a4 = devm_kzalloc(&hdev->dev, sizeof(*a4), GFP_KERNEL);
 119         if (a4 == NULL) {
 120                 hid_err(hdev, "can't alloc device descriptor\n");
 121                 return -ENOMEM;
 122         }
 123 
 124         a4->quirks = id->driver_data;
 125 
 126         hid_set_drvdata(hdev, a4);
 127 
 128         ret = hid_parse(hdev);
 129         if (ret) {
 130                 hid_err(hdev, "parse failed\n");
 131                 return ret;
 132         }
 133 
 134         ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 135         if (ret) {
 136                 hid_err(hdev, "hw start failed\n");
 137                 return ret;
 138         }
 139 
 140         return 0;
 141 }
 142 
 143 static const struct hid_device_id a4_devices[] = {
 144         { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_WCP32PU),
 145                 .driver_data = A4_2WHEEL_MOUSE_HACK_7 },
 146         { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_X5_005D),
 147                 .driver_data = A4_2WHEEL_MOUSE_HACK_B8 },
 148         { HID_USB_DEVICE(USB_VENDOR_ID_A4TECH, USB_DEVICE_ID_A4TECH_RP_649),
 149                 .driver_data = A4_2WHEEL_MOUSE_HACK_B8 },
 150         { }
 151 };
 152 MODULE_DEVICE_TABLE(hid, a4_devices);
 153 
 154 static struct hid_driver a4_driver = {
 155         .name = "a4tech",
 156         .id_table = a4_devices,
 157         .input_mapping = a4_input_mapping,
 158         .input_mapped = a4_input_mapped,
 159         .event = a4_event,
 160         .probe = a4_probe,
 161 };
 162 module_hid_driver(a4_driver);
 163 
 164 MODULE_LICENSE("GPL");