drivers/input/mouse/focaltech.c

   1 /*
   2  * Focaltech TouchPad PS/2 mouse driver
   3  *
   4  * Copyright (c) 2014 Red Hat Inc.
   5  * Copyright (c) 2014 Mathias Gottschlag <mgottschlag@gmail.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * Red Hat authors:
  13  *
  14  * Hans de Goede <hdegoede@redhat.com>
  15  */
  16
  17
  18 #include <linux/device.h>
  19 #include <linux/libps2.h>
  20 #include <linux/input/mt.h>
  21 #include <linux/serio.h>
  22 #include <linux/slab.h>
  23 #include "psmouse.h"
  24 #include "focaltech.h"
  25
  26 static const char * const focaltech_pnp_ids[] = {
  27         "FLT0101",
  28         "FLT0102",
  29         "FLT0103",
  30         NULL
  31 };
  32
  33 /*
  34  * Even if the kernel is built without support for Focaltech PS/2 touchpads (or
  35  * when the real driver fails to recognize the device), we still have to detect
  36  * them in order to avoid further detection attempts confusing the touchpad.
  37  * This way it at least works in PS/2 mouse compatibility mode.
  38  */
  39 int focaltech_detect(struct psmouse *psmouse, bool set_properties)
  40 {
  41         if (!psmouse_matches_pnp_id(psmouse, focaltech_pnp_ids))
  42                 return -ENODEV;
  43
  44         if (set_properties) {
  45                 psmouse->vendor = "FocalTech";
  46                 psmouse->name = "FocalTech Touchpad";
  47         }
  48
  49         return 0;
  50 }
  51
  52 static void focaltech_reset(struct psmouse *psmouse)
  53 {
  54         ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
  55         psmouse_reset(psmouse);
  56 }
  57
  58 #ifdef CONFIG_MOUSE_PS2_FOCALTECH
  59
  60 /*
  61  * Packet types - the numbers are not consecutive, so we might be missing
  62  * something here.
  63  */
  64 #define FOC_TOUCH 0x3 /* bitmap of active fingers */
  65 #define FOC_ABS 0x6 /* absolute position of one finger */
  66 #define FOC_REL 0x9 /* relative position of 1-2 fingers */
  67
  68 #define FOC_MAX_FINGERS 5
  69
  70 /*
  71  * Current state of a single finger on the touchpad.
  72  */
  73 struct focaltech_finger_state {
  74         /* The touchpad has generated a touch event for the finger */
  75         bool active;
  76
  77         /*
  78          * The touchpad has sent position data for the finger. The
  79          * flag is 0 when the finger is not active, and there is a
  80          * time between the first touch event for the finger and the
  81          * following absolute position packet for the finger where the
  82          * touchpad has declared the finger to be valid, but we do not
  83          * have any valid position yet.
  84          */
  85         bool valid;
  86
  87         /*
  88          * Absolute position (from the bottom left corner) of the
  89          * finger.
  90          */
  91         unsigned int x;
  92         unsigned int y;
  93 };
  94
  95 /*
  96  * Description of the current state of the touchpad hardware.
  97  */
  98 struct focaltech_hw_state {
  99         /*
 100          * The touchpad tracks the positions of the fingers for us,
 101          * the array indices correspond to the finger indices returned
 102          * in the report packages.
 103          */
 104         struct focaltech_finger_state fingers[FOC_MAX_FINGERS];
 105
 106         /* True if the clickpad has been pressed. */
 107         bool pressed;
 108 };
 109
 110 struct focaltech_data {
 111         unsigned int x_max, y_max;
 112         struct focaltech_hw_state state;
 113 };
 114
 115 static void focaltech_report_state(struct psmouse *psmouse)
 116 {
 117         struct focaltech_data *priv = psmouse->private;
 118         struct focaltech_hw_state *state = &priv->state;
 119         struct input_dev *dev = psmouse->dev;
 120         int i;
 121
 122         for (i = 0; i < FOC_MAX_FINGERS; i++) {
 123                 struct focaltech_finger_state *finger = &state->fingers[i];
 124                 bool active = finger->active && finger->valid;
 125
 126                 input_mt_slot(dev, i);
 127                 input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
 128                 if (active) {
 129                         unsigned int clamped_x, clamped_y;
 130                         /*
 131                          * The touchpad might report invalid data, so we clamp
 132                          * the resulting values so that we do not confuse
 133                          * userspace.
 134                          */
 135                         clamped_x = clamp(finger->x, 0U, priv->x_max);
 136                         clamped_y = clamp(finger->y, 0U, priv->y_max);
 137                         input_report_abs(dev, ABS_MT_POSITION_X, clamped_x);
 138                         input_report_abs(dev, ABS_MT_POSITION_Y,
 139                                          priv->y_max - clamped_y);
 140                 }
 141         }
 142         input_mt_report_pointer_emulation(dev, true);
 143
 144         input_report_key(psmouse->dev, BTN_LEFT, state->pressed);
 145         input_sync(psmouse->dev);
 146 }
 147
 148 static void focaltech_process_touch_packet(struct psmouse *psmouse,
 149                                            unsigned char *packet)
 150 {
 151         struct focaltech_data *priv = psmouse->private;
 152         struct focaltech_hw_state *state = &priv->state;
 153         unsigned char fingers = packet[1];
 154         int i;
 155
 156         state->pressed = (packet[0] >> 4) & 1;
 157
 158         /* the second byte contains a bitmap of all fingers touching the pad */
 159         for (i = 0; i < FOC_MAX_FINGERS; i++) {
 160                 state->fingers[i].active = fingers & 0x1;
 161                 if (!state->fingers[i].active) {
 162                         /*
 163                          * Even when the finger becomes active again, we still
 164                          * will have to wait for the first valid position.
 165                          */
 166                         state->fingers[i].valid = false;
 167                 }
 168                 fingers >>= 1;
 169         }
 170 }
 171
 172 static void focaltech_process_abs_packet(struct psmouse *psmouse,
 173                                          unsigned char *packet)
 174 {
 175         struct focaltech_data *priv = psmouse->private;
 176         struct focaltech_hw_state *state = &priv->state;
 177         unsigned int finger;
 178
 179         finger = (packet[1] >> 4) - 1;
 180         if (finger >= FOC_MAX_FINGERS) {
 181                 psmouse_err(psmouse, "Invalid finger in abs packet: %d\n",
 182                             finger);
 183                 return;
 184         }
 185
 186         state->pressed = (packet[0] >> 4) & 1;
 187
 188         /*
 189          * packet[5] contains some kind of tool size in the most
 190          * significant nibble. 0xff is a special value (latching) that
 191          * signals a large contact area.
 192          */
 193         if (packet[5] == 0xff) {
 194                 state->fingers[finger].valid = false;
 195                 return;
 196         }
 197
 198         state->fingers[finger].x = ((packet[1] & 0xf) << 8) | packet[2];
 199         state->fingers[finger].y = (packet[3] << 8) | packet[4];
 200         state->fingers[finger].valid = true;
 201 }
 202
 203 static void focaltech_process_rel_packet(struct psmouse *psmouse,
 204                                          unsigned char *packet)
 205 {
 206         struct focaltech_data *priv = psmouse->private;
 207         struct focaltech_hw_state *state = &priv->state;
 208         int finger1, finger2;
 209
 210         state->pressed = packet[0] >> 7;
 211         finger1 = ((packet[0] >> 4) & 0x7) - 1;
 212         if (finger1 < FOC_MAX_FINGERS) {
 213                 state->fingers[finger1].x += (char)packet[1];
 214                 state->fingers[finger1].y += (char)packet[2];
 215         } else {
 216                 psmouse_err(psmouse, "First finger in rel packet invalid: %d\n",
 217                             finger1);
 218         }
 219
 220         /*
 221          * If there is an odd number of fingers, the last relative
 222          * packet only contains one finger. In this case, the second
 223          * finger index in the packet is 0 (we subtract 1 in the lines
 224          * above to create array indices, so the finger will overflow
 225          * and be above FOC_MAX_FINGERS).
 226          */
 227         finger2 = ((packet[3] >> 4) & 0x7) - 1;
 228         if (finger2 < FOC_MAX_FINGERS) {
 229                 state->fingers[finger2].x += (char)packet[4];
 230                 state->fingers[finger2].y += (char)packet[5];
 231         }
 232 }
 233
 234 static void focaltech_process_packet(struct psmouse *psmouse)
 235 {
 236         unsigned char *packet = psmouse->packet;
 237
 238         switch (packet[0] & 0xf) {
 239         case FOC_TOUCH:
 240                 focaltech_process_touch_packet(psmouse, packet);
 241                 break;
 242
 243         case FOC_ABS:
 244                 focaltech_process_abs_packet(psmouse, packet);
 245                 break;
 246
 247         case FOC_REL:
 248                 focaltech_process_rel_packet(psmouse, packet);
 249                 break;
 250
 251         default:
 252                 psmouse_err(psmouse, "Unknown packet type: %02x\n", packet[0]);
 253                 break;
 254         }
 255
 256         focaltech_report_state(psmouse);
 257 }
 258
 259 static psmouse_ret_t focaltech_process_byte(struct psmouse *psmouse)
 260 {
 261         if (psmouse->pktcnt >= 6) { /* Full packet received */
 262                 focaltech_process_packet(psmouse);
 263                 return PSMOUSE_FULL_PACKET;
 264         }
 265
 266         /*
 267          * We might want to do some validation of the data here, but
 268          * we do not know the protocol well enough
 269          */
 270         return PSMOUSE_GOOD_DATA;
 271 }
 272
 273 static int focaltech_switch_protocol(struct psmouse *psmouse)
 274 {
 275         struct ps2dev *ps2dev = &psmouse->ps2dev;
 276         unsigned char param[3];
 277
 278         param[0] = 0;
 279         if (ps2_command(ps2dev, param, 0x10f8))
 280                 return -EIO;
 281
 282         if (ps2_command(ps2dev, param, 0x10f8))
 283                 return -EIO;
 284
 285         if (ps2_command(ps2dev, param, 0x10f8))
 286                 return -EIO;
 287
 288         param[0] = 1;
 289         if (ps2_command(ps2dev, param, 0x10f8))
 290                 return -EIO;
 291
 292         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
 293                 return -EIO;
 294
 295         if (ps2_command(ps2dev, param, PSMOUSE_CMD_ENABLE))
 296                 return -EIO;
 297
 298         return 0;
 299 }
 300
 301 static void focaltech_disconnect(struct psmouse *psmouse)
 302 {
 303         focaltech_reset(psmouse);
 304         kfree(psmouse->private);
 305         psmouse->private = NULL;
 306 }
 307
 308 static int focaltech_reconnect(struct psmouse *psmouse)
 309 {
 310         int error;
 311
 312         focaltech_reset(psmouse);
 313
 314         error = focaltech_switch_protocol(psmouse);
 315         if (error) {
 316                 psmouse_err(psmouse, "Unable to initialize the device\n");
 317                 return error;
 318         }
 319
 320         return 0;
 321 }
 322
 323 static void focaltech_set_input_params(struct psmouse *psmouse)
 324 {
 325         struct input_dev *dev = psmouse->dev;
 326         struct focaltech_data *priv = psmouse->private;
 327
 328         /*
 329          * Undo part of setup done for us by psmouse core since touchpad
 330          * is not a relative device.
 331          */
 332         __clear_bit(EV_REL, dev->evbit);
 333         __clear_bit(REL_X, dev->relbit);
 334         __clear_bit(REL_Y, dev->relbit);
 335         __clear_bit(BTN_RIGHT, dev->keybit);
 336         __clear_bit(BTN_MIDDLE, dev->keybit);
 337
 338         /*
 339          * Now set up our capabilities.
 340          */
 341         __set_bit(EV_ABS, dev->evbit);
 342         input_set_abs_params(dev, ABS_MT_POSITION_X, 0, priv->x_max, 0, 0);
 343         input_set_abs_params(dev, ABS_MT_POSITION_Y, 0, priv->y_max, 0, 0);
 344         input_mt_init_slots(dev, 5, INPUT_MT_POINTER);
 345         __set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
 346 }
 347
 348 static int focaltech_read_register(struct ps2dev *ps2dev, int reg,
 349                                    unsigned char *param)
 350 {
 351         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
 352                 return -EIO;
 353
 354         param[0] = 0;
 355         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 356                 return -EIO;
 357
 358         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 359                 return -EIO;
 360
 361         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 362                 return -EIO;
 363
 364         param[0] = reg;
 365         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 366                 return -EIO;
 367
 368         if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
 369                 return -EIO;
 370
 371         return 0;
 372 }
 373
 374 static int focaltech_read_size(struct psmouse *psmouse)
 375 {
 376         struct ps2dev *ps2dev = &psmouse->ps2dev;
 377         struct focaltech_data *priv = psmouse->private;
 378         char param[3];
 379
 380         if (focaltech_read_register(ps2dev, 2, param))
 381                 return -EIO;
 382
 383         /* not sure whether this is 100% correct */
 384         priv->x_max = (unsigned char)param[1] * 128;
 385         priv->y_max = (unsigned char)param[2] * 128;
 386
 387         return 0;
 388 }
 389
 390 void focaltech_set_resolution(struct psmouse *psmouse, unsigned int resolution)
 391 {
 392         /* not supported yet */
 393 }
 394
 395 static void focaltech_set_rate(struct psmouse *psmouse, unsigned int rate)
 396 {
 397         /* not supported yet */
 398 }
 399
 400 static void focaltech_set_scale(struct psmouse *psmouse,
 401                                 enum psmouse_scale scale)
 402 {
 403         /* not supported yet */
 404 }
 405
 406 int focaltech_init(struct psmouse *psmouse)
 407 {
 408         struct focaltech_data *priv;
 409         int error;
 410
 411         psmouse->private = priv = kzalloc(sizeof(struct focaltech_data),
 412                                           GFP_KERNEL);
 413         if (!priv)
 414                 return -ENOMEM;
 415
 416         focaltech_reset(psmouse);
 417
 418         error = focaltech_read_size(psmouse);
 419         if (error) {
 420                 psmouse_err(psmouse,
 421                             "Unable to read the size of the touchpad\n");
 422                 goto fail;
 423         }
 424
 425         error = focaltech_switch_protocol(psmouse);
 426         if (error) {
 427                 psmouse_err(psmouse, "Unable to initialize the device\n");
 428                 goto fail;
 429         }
 430
 431         focaltech_set_input_params(psmouse);
 432
 433         psmouse->protocol_handler = focaltech_process_byte;
 434         psmouse->pktsize = 6;
 435         psmouse->disconnect = focaltech_disconnect;
 436         psmouse->reconnect = focaltech_reconnect;
 437         psmouse->cleanup = focaltech_reset;
 438         /* resync is not supported yet */
 439         psmouse->resync_time = 0;
 440         /*
 441          * rate/resolution/scale changes are not supported yet, and
 442          * the generic implementations of these functions seem to
 443          * confuse some touchpads
 444          */
 445         psmouse->set_resolution = focaltech_set_resolution;
 446         psmouse->set_rate = focaltech_set_rate;
 447         psmouse->set_scale = focaltech_set_scale;
 448
 449         return 0;
 450
 451 fail:
 452         focaltech_reset(psmouse);
 453         kfree(priv);
 454         return error;
 455 }
 456
 457 #else /* CONFIG_MOUSE_PS2_FOCALTECH */
 458
 459 int focaltech_init(struct psmouse *psmouse)
 460 {
 461         focaltech_reset(psmouse);
 462
 463         return 0;
 464 }
 465
 466 #endif /* CONFIG_MOUSE_PS2_FOCALTECH */