drivers/hid/hid-ntrig.c

   1 /*
   2  *  HID driver for N-Trig touchscreens
   3  *
   4  *  Copyright (c) 2008 Rafi Rubin
   5  *  Copyright (c) 2009 Stephane Chatty
   6  *
   7  */
   8
   9 /*
  10  * This program is free software; you can redistribute it and/or modify it
  11  * under the terms of the GNU General Public License as published by the Free
  12  * Software Foundation; either version 2 of the License, or (at your option)
  13  * any later version.
  14  */
  15
  16 #include <linux/device.h>
  17 #include <linux/hid.h>
  18 #include <linux/module.h>
  19
  20 #include "hid-ids.h"
  21
  22 #define NTRIG_DUPLICATE_USAGES  0x001
  23
  24 #define nt_map_key_clear(c)     hid_map_usage_clear(hi, usage, bit, max, \
  25                                         EV_KEY, (c))
  26
  27 struct ntrig_data {
  28         __s32 x, y, id, w, h;
  29         char reading_a_point, found_contact_id;
  30 };
  31
  32 /*
  33  * this driver is aimed at two firmware versions in circulation:
  34  *  - dual pen/finger single touch
  35  *  - finger multitouch, pen not working
  36  */
  37
  38 static int ntrig_input_mapping(struct hid_device *hdev, struct hid_input *hi,
  39                 struct hid_field *field, struct hid_usage *usage,
  40                 unsigned long **bit, int *max)
  41 {
  42         switch (usage->hid & HID_USAGE_PAGE) {
  43
  44         case HID_UP_GENDESK:
  45                 switch (usage->hid) {
  46                 case HID_GD_X:
  47                         hid_map_usage(hi, usage, bit, max,
  48                                         EV_ABS, ABS_MT_POSITION_X);
  49                         input_set_abs_params(hi->input, ABS_X,
  50                                         field->logical_minimum,
  51                                         field->logical_maximum, 0, 0);
  52                         return 1;
  53                 case HID_GD_Y:
  54                         hid_map_usage(hi, usage, bit, max,
  55                                         EV_ABS, ABS_MT_POSITION_Y);
  56                         input_set_abs_params(hi->input, ABS_Y,
  57                                         field->logical_minimum,
  58                                         field->logical_maximum, 0, 0);
  59                         return 1;
  60                 }
  61                 return 0;
  62
  63         case HID_UP_DIGITIZER:
  64                 switch (usage->hid) {
  65                 /* we do not want to map these for now */
  66                 case HID_DG_INVERT: /* value is always 0 */
  67                 case HID_DG_ERASER: /* value is always 0 */
  68                 case HID_DG_CONTACTID: /* value is useless */
  69                 case HID_DG_BARRELSWITCH:  /* doubtful */
  70                 case HID_DG_INPUTMODE:
  71                 case HID_DG_DEVICEINDEX:
  72                 case HID_DG_CONTACTCOUNT:
  73                 case HID_DG_CONTACTMAX:
  74                         return -1;
  75
  76                 /* original mapping by Rafi Rubin */
  77                 case HID_DG_CONFIDENCE:
  78                         nt_map_key_clear(BTN_TOOL_DOUBLETAP);
  79                         return 1;
  80
  81                 /* width/height mapped on TouchMajor/TouchMinor/Orientation */
  82                 case HID_DG_WIDTH:
  83                         hid_map_usage(hi, usage, bit, max,
  84                                         EV_ABS, ABS_MT_TOUCH_MAJOR);
  85                         return 1;
  86                 case HID_DG_HEIGHT:
  87                         hid_map_usage(hi, usage, bit, max,
  88                                         EV_ABS, ABS_MT_TOUCH_MINOR);
  89                         input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
  90                                         0, 1, 0, 0);
  91                         return 1;
  92                 }
  93                 return 0;
  94
  95         case 0xff000000:
  96                 /* we do not want to map these: no input-oriented meaning */
  97                 return -1;
  98         }
  99
 100         return 0;
 101 }
 102
 103 static int ntrig_input_mapped(struct hid_device *hdev, struct hid_input *hi,
 104                 struct hid_field *field, struct hid_usage *usage,
 105                 unsigned long **bit, int *max)
 106 {
 107         if (usage->type == EV_KEY || usage->type == EV_REL
 108                         || usage->type == EV_ABS)
 109                 clear_bit(usage->code, *bit);
 110
 111         return 0;
 112 }
 113
 114 /*
 115  * this function is called upon all reports
 116  * so that we can filter contact point information,
 117  * decide whether we are in multi or single touch mode
 118  * and call input_mt_sync after each point if necessary
 119  */
 120 static int ntrig_event (struct hid_device *hid, struct hid_field *field,
 121                                         struct hid_usage *usage, __s32 value)
 122 {
 123         struct input_dev *input = field->hidinput->input;
 124         struct ntrig_data *nd = hid_get_drvdata(hid);
 125
 126         if (hid->claimed & HID_CLAIMED_INPUT) {
 127                 switch (usage->hid) {
 128                 case HID_GD_X:
 129                         nd->x = value;
 130                         nd->reading_a_point = 1;
 131                         break;
 132                 case HID_GD_Y:
 133                         nd->y = value;
 134                         break;
 135                 case HID_DG_CONTACTID:
 136                         nd->id = value;
 137                         /* we receive this only when in multitouch mode */
 138                         nd->found_contact_id = 1;
 139                         break;
 140                 case HID_DG_WIDTH:
 141                         nd->w = value;
 142                         break;
 143                 case HID_DG_HEIGHT:
 144                         nd->h = value;
 145                         /*
 146                          * when in single touch mode, this is the last
 147                          * report received in a finger event. We want
 148                          * to emit a normal (X, Y) position
 149                          */
 150                         if (! nd->found_contact_id) {
 151                                 input_event(input, EV_ABS, ABS_X, nd->x);
 152                                 input_event(input, EV_ABS, ABS_Y, nd->y);
 153                         }
 154                         break;
 155                 case HID_DG_TIPPRESSURE:
 156                         /*
 157                          * when in single touch mode, this is the last
 158                          * report received in a pen event. We want
 159                          * to emit a normal (X, Y) position
 160                          */
 161                         if (! nd->found_contact_id) {
 162                                 input_event(input, EV_ABS, ABS_X, nd->x);
 163                                 input_event(input, EV_ABS, ABS_Y, nd->y);
 164                                 input_event(input, EV_ABS, ABS_PRESSURE, value);
 165                         }
 166                         break;
 167                 case 0xff000002:
 168                         /*
 169                          * we receive this when the device is in multitouch
 170                          * mode. The first of the three values tagged with
 171                          * this usage tells if the contact point is real
 172                          * or a placeholder
 173                          */
 174                         if (!nd->reading_a_point || value != 1)
 175                                 break;
 176                         /* emit a normal (X, Y) for the first point only */
 177                         if (nd->id == 0) {
 178                                 input_event(input, EV_ABS, ABS_X, nd->x);
 179                                 input_event(input, EV_ABS, ABS_Y, nd->y);
 180                         }
 181                         input_event(input, EV_ABS, ABS_MT_POSITION_X, nd->x);
 182                         input_event(input, EV_ABS, ABS_MT_POSITION_Y, nd->y);
 183                         if (nd->w > nd->h) {
 184                                 input_event(input, EV_ABS,
 185                                                 ABS_MT_ORIENTATION, 1);
 186                                 input_event(input, EV_ABS,
 187                                                 ABS_MT_TOUCH_MAJOR, nd->w);
 188                                 input_event(input, EV_ABS,
 189                                                 ABS_MT_TOUCH_MINOR, nd->h);
 190                         } else {
 191                                 input_event(input, EV_ABS,
 192                                                 ABS_MT_ORIENTATION, 0);
 193                                 input_event(input, EV_ABS,
 194                                                 ABS_MT_TOUCH_MAJOR, nd->h);
 195                                 input_event(input, EV_ABS,
 196                                                 ABS_MT_TOUCH_MINOR, nd->w);
 197                         }
 198                         input_mt_sync(field->hidinput->input);
 199                         nd->reading_a_point = 0;
 200                         nd->found_contact_id = 0;
 201                         break;
 202
 203                 default:
 204                         /* fallback to the generic hidinput handling */
 205                         return 0;
 206                 }
 207         }
 208
 209         /* we have handled the hidinput part, now remains hiddev */
 210         if (hid->claimed & HID_CLAIMED_HIDDEV && hid->hiddev_hid_event)
 211                 hid->hiddev_hid_event(hid, field, usage, value);
 212
 213         return 1;
 214 }
 215
 216 static int ntrig_probe(struct hid_device *hdev, const struct hid_device_id *id)
 217 {
 218         int ret;
 219         struct ntrig_data *nd;
 220
 221         nd = kmalloc(sizeof(struct ntrig_data), GFP_KERNEL);
 222         if (!nd) {
 223                 dev_err(&hdev->dev, "cannot allocate N-Trig data\n");
 224                 return -ENOMEM;
 225         }
 226         nd->reading_a_point = 0;
 227         nd->found_contact_id = 0;
 228         hid_set_drvdata(hdev, nd);
 229
 230         ret = hid_parse(hdev);
 231         if (!ret)
 232                 ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 233
 234         if (ret)
 235                 kfree (nd);
 236         return ret;
 237 }
 238
 239 static void ntrig_remove(struct hid_device *hdev)
 240 {
 241         hid_hw_stop(hdev);
 242         kfree(hid_get_drvdata(hdev));
 243 }
 244
 245 static const struct hid_device_id ntrig_devices[] = {
 246         { HID_USB_DEVICE(USB_VENDOR_ID_NTRIG, USB_DEVICE_ID_NTRIG_TOUCH_SCREEN),
 247                 .driver_data = NTRIG_DUPLICATE_USAGES },
 248         { }
 249 };
 250 MODULE_DEVICE_TABLE(hid, ntrig_devices);
 251
 252 static const struct hid_usage_id ntrig_grabbed_usages[] = {
 253         { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID },
 254         { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
 255 };
 256
 257 static struct hid_driver ntrig_driver = {
 258         .name = "ntrig",
 259         .id_table = ntrig_devices,
 260         .probe = ntrig_probe,
 261         .remove = ntrig_remove,
 262         .input_mapping = ntrig_input_mapping,
 263         .input_mapped = ntrig_input_mapped,
 264         .usage_table = ntrig_grabbed_usages,
 265         .event = ntrig_event,
 266 };
 267
 268 static int ntrig_init(void)
 269 {
 270         return hid_register_driver(&ntrig_driver);
 271 }
 272
 273 static void ntrig_exit(void)
 274 {
 275         hid_unregister_driver(&ntrig_driver);
 276 }
 277
 278 module_init(ntrig_init);
 279 module_exit(ntrig_exit);
 280 MODULE_LICENSE("GPL");