LXR linux/drivers/hid/hid-stantum.c

   1/*
   2 *  HID driver for Stantum multitouch panels
   3 *
   4 *  Copyright (c) 2009 Stephane Chatty <chatty@enac.fr>
   5 *
   6 */
   7
   8/*
   9 * This program is free software; you can redistribute it and/or modify it
  10 * under the terms of the GNU General Public License as published by the Free
  11 * Software Foundation; either version 2 of the License, or (at your option)
  12 * any later version.
  13 */
  14
  15#include <linux/device.h>
  16#include <linux/hid.h>
  17#include <linux/module.h>
  18#include <linux/slab.h>
  19
  20MODULE_AUTHOR("Stephane Chatty <chatty@enac.fr>");
  21MODULE_DESCRIPTION("Stantum HID multitouch panels");
  22MODULE_LICENSE("GPL");
  23
  24#include "hid-ids.h"
  25
  26struct stantum_data {
  27        __s32 x, y, z, w, h;    /* x, y, pressure, width, height */
  28        __u16 id;               /* touch id */
  29        bool valid;             /* valid finger data, or just placeholder? */
  30        bool first;             /* first finger in the HID packet? */
  31        bool activity;          /* at least one active finger so far? */
  32};
  33
  34static int stantum_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        switch (usage->hid & HID_USAGE_PAGE) {
  39
  40        case HID_UP_GENDESK:
  41                switch (usage->hid) {
  42                case HID_GD_X:
  43                        hid_map_usage(hi, usage, bit, max,
  44                                        EV_ABS, ABS_MT_POSITION_X);
  45                        /* touchscreen emulation */
  46                        input_set_abs_params(hi->input, ABS_X,
  47                                                field->logical_minimum,
  48                                                field->logical_maximum, 0, 0);
  49                        return 1;
  50                case HID_GD_Y:
  51                        hid_map_usage(hi, usage, bit, max,
  52                                        EV_ABS, ABS_MT_POSITION_Y);
  53                        /* touchscreen emulation */
  54                        input_set_abs_params(hi->input, ABS_Y,
  55                                                field->logical_minimum,
  56                                                field->logical_maximum, 0, 0);
  57                        return 1;
  58                }
  59                return 0;
  60
  61        case HID_UP_DIGITIZER:
  62                switch (usage->hid) {
  63                case HID_DG_INRANGE:
  64                case HID_DG_CONFIDENCE:
  65                case HID_DG_INPUTMODE:
  66                case HID_DG_DEVICEINDEX:
  67                case HID_DG_CONTACTCOUNT:
  68                case HID_DG_CONTACTMAX:
  69                        return -1;
  70
  71                case HID_DG_TIPSWITCH:
  72                        /* touchscreen emulation */
  73                        hid_map_usage(hi, usage, bit, max, EV_KEY, BTN_TOUCH);
  74                        return 1;
  75
  76                case HID_DG_WIDTH:
  77                        hid_map_usage(hi, usage, bit, max,
  78                                        EV_ABS, ABS_MT_TOUCH_MAJOR);
  79                        return 1;
  80                case HID_DG_HEIGHT:
  81                        hid_map_usage(hi, usage, bit, max,
  82                                        EV_ABS, ABS_MT_TOUCH_MINOR);
  83                        input_set_abs_params(hi->input, ABS_MT_ORIENTATION,
  84                                        1, 1, 0, 0);
  85                        return 1;
  86                case HID_DG_TIPPRESSURE:
  87                        hid_map_usage(hi, usage, bit, max,
  88                                        EV_ABS, ABS_MT_PRESSURE);
  89                        return 1;
  90
  91                case HID_DG_CONTACTID:
  92                        hid_map_usage(hi, usage, bit, max,
  93                                        EV_ABS, ABS_MT_TRACKING_ID);
  94                        return 1;
  95
  96                }
  97                return 0;
  98
  99        case 0xff000000:
 100                /* no input-oriented meaning */
 101                return -1;
 102        }
 103
 104        return 0;
 105}
 106
 107static int stantum_input_mapped(struct hid_device *hdev, struct hid_input *hi,
 108                struct hid_field *field, struct hid_usage *usage,
 109                unsigned long **bit, int *max)
 110{
 111        if (usage->type == EV_KEY || usage->type == EV_ABS)
 112                clear_bit(usage->code, *bit);
 113
 114        return 0;
 115}
 116
 117/*
 118 * this function is called when a whole finger has been parsed,
 119 * so that it can decide what to send to the input layer.
 120 */
 121static void stantum_filter_event(struct stantum_data *sd,
 122                                        struct input_dev *input)
 123{
 124        bool wide;
 125
 126        if (!sd->valid) {
 127                /*
 128                 * touchscreen emulation: if the first finger is not valid and
 129                 * there previously was finger activity, this is a release
 130                 */
 131                if (sd->first && sd->activity) {
 132                        input_event(input, EV_KEY, BTN_TOUCH, 0);
 133                        sd->activity = false;
 134                }
 135                return;
 136        }
 137
 138        input_event(input, EV_ABS, ABS_MT_TRACKING_ID, sd->id);
 139        input_event(input, EV_ABS, ABS_MT_POSITION_X, sd->x);
 140        input_event(input, EV_ABS, ABS_MT_POSITION_Y, sd->y);
 141
 142        wide = (sd->w > sd->h);
 143        input_event(input, EV_ABS, ABS_MT_ORIENTATION, wide);
 144        input_event(input, EV_ABS, ABS_MT_TOUCH_MAJOR, wide ? sd->w : sd->h);
 145        input_event(input, EV_ABS, ABS_MT_TOUCH_MINOR, wide ? sd->h : sd->w);
 146
 147        input_event(input, EV_ABS, ABS_MT_PRESSURE, sd->z);
 148
 149        input_mt_sync(input);
 150        sd->valid = false;
 151
 152        /* touchscreen emulation */
 153        if (sd->first) {
 154                if (!sd->activity) {
 155                        input_event(input, EV_KEY, BTN_TOUCH, 1);
 156                        sd->activity = true;
 157                }
 158                input_event(input, EV_ABS, ABS_X, sd->x);
 159                input_event(input, EV_ABS, ABS_Y, sd->y);
 160        }
 161        sd->first = false;
 162}
 163
 164
 165static int stantum_event(struct hid_device *hid, struct hid_field *field,
 166                                struct hid_usage *usage, __s32 value)
 167{
 168        struct stantum_data *sd = hid_get_drvdata(hid);
 169
 170        if (hid->claimed & HID_CLAIMED_INPUT) {
 171                struct input_dev *input = field->hidinput->input;
 172
 173                switch (usage->hid) {
 174                case HID_DG_INRANGE:
 175                        /* this is the last field in a finger */
 176                        stantum_filter_event(sd, input);
 177                        break;
 178                case HID_DG_WIDTH:
 179                        sd->w = value;
 180                        break;
 181                case HID_DG_HEIGHT:
 182                        sd->h = value;
 183                        break;
 184                case HID_GD_X:
 185                        sd->x = value;
 186                        break;
 187                case HID_GD_Y:
 188                        sd->y = value;
 189                        break;
 190                case HID_DG_TIPPRESSURE:
 191                        sd->z = value;
 192                        break;
 193                case HID_DG_CONTACTID:
 194                        sd->id = value;
 195                        break;
 196                case HID_DG_CONFIDENCE:
 197                        sd->valid = !!value;
 198                        break;
 199                case 0xff000002:
 200                        /* this comes only before the first finger */
 201                        sd->first = true;
 202                        break;
 203
 204                default:
 205                        /* ignore the others */
 206                        return 1;
 207                }
 208        }
 209
 210        /* we have handled the hidinput part, now remains hiddev */
 211        if (hid->claimed & HID_CLAIMED_HIDDEV && hid->hiddev_hid_event)
 212                hid->hiddev_hid_event(hid, field, usage, value);
 213
 214        return 1;
 215}
 216
 217static int stantum_probe(struct hid_device *hdev,
 218                                const struct hid_device_id *id)
 219{
 220        int ret;
 221        struct stantum_data *sd;
 222
 223        sd = kmalloc(sizeof(struct stantum_data), GFP_KERNEL);
 224        if (!sd) {
 225                hid_err(hdev, "cannot allocate Stantum data\n");
 226                return -ENOMEM;
 227        }
 228        sd->valid = false;
 229        sd->first = false;
 230        sd->activity = false;
 231        hid_set_drvdata(hdev, sd);
 232
 233        ret = hid_parse(hdev);
 234        if (!ret)
 235                ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
 236
 237        if (ret)
 238                kfree(sd);
 239
 240        return ret;
 241}
 242
 243static void stantum_remove(struct hid_device *hdev)
 244{
 245        hid_hw_stop(hdev);
 246        kfree(hid_get_drvdata(hdev));
 247        hid_set_drvdata(hdev, NULL);
 248}
 249
 250static const struct hid_device_id stantum_devices[] = {
 251        { HID_USB_DEVICE(USB_VENDOR_ID_STANTUM, USB_DEVICE_ID_MTP) },
 252        { HID_USB_DEVICE(USB_VENDOR_ID_STANTUM_STM, USB_DEVICE_ID_MTP_STM) },
 253        { HID_USB_DEVICE(USB_VENDOR_ID_STANTUM_SITRONIX, USB_DEVICE_ID_MTP_SITRONIX) },
 254        { }
 255};
 256MODULE_DEVICE_TABLE(hid, stantum_devices);
 257
 258static const struct hid_usage_id stantum_grabbed_usages[] = {
 259        { HID_ANY_ID, HID_ANY_ID, HID_ANY_ID },
 260        { HID_ANY_ID - 1, HID_ANY_ID - 1, HID_ANY_ID - 1}
 261};
 262
 263static struct hid_driver stantum_driver = {
 264        .name = "stantum",
 265        .id_table = stantum_devices,
 266        .probe = stantum_probe,
 267        .remove = stantum_remove,
 268        .input_mapping = stantum_input_mapping,
 269        .input_mapped = stantum_input_mapped,
 270        .usage_table = stantum_grabbed_usages,
 271        .event = stantum_event,
 272};
 273
 274static int __init stantum_init(void)
 275{
 276        return hid_register_driver(&stantum_driver);
 277}
 278
 279static void __exit stantum_exit(void)
 280{
 281        hid_unregister_driver(&stantum_driver);
 282}
 283
 284module_init(stantum_init);
 285module_exit(stantum_exit);
 286
 287