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         /*
 107          * Finger width 0-7 and 15 for a very big contact area.
 108          * 15 value stays until the finger is released.
 109          * Width is reported only in absolute packets.
 110          * Since hardware reports width only for last touching finger,
 111          * there is no need to store width for every specific finger,
 112          * so we keep only last value reported.
 113          */
 114         unsigned int width;
 115
 116         /* True if the clickpad has been pressed. */
 117         bool pressed;
 118 };
 119
 120 struct focaltech_data {
 121         unsigned int x_max, y_max;
 122         struct focaltech_hw_state state;
 123 };
 124
 125 static void focaltech_report_state(struct psmouse *psmouse)
 126 {
 127         struct focaltech_data *priv = psmouse->private;
 128         struct focaltech_hw_state *state = &priv->state;
 129         struct input_dev *dev = psmouse->dev;
 130         int i;
 131
 132         for (i = 0; i < FOC_MAX_FINGERS; i++) {
 133                 struct focaltech_finger_state *finger = &state->fingers[i];
 134                 bool active = finger->active && finger->valid;
 135
 136                 input_mt_slot(dev, i);
 137                 input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
 138                 if (active) {
 139                         unsigned int clamped_x, clamped_y;
 140                         /*
 141                          * The touchpad might report invalid data, so we clamp
 142                          * the resulting values so that we do not confuse
 143                          * userspace.
 144                          */
 145                         clamped_x = clamp(finger->x, 0U, priv->x_max);
 146                         clamped_y = clamp(finger->y, 0U, priv->y_max);
 147                         input_report_abs(dev, ABS_MT_POSITION_X, clamped_x);
 148                         input_report_abs(dev, ABS_MT_POSITION_Y,
 149                                          priv->y_max - clamped_y);
 150                         input_report_abs(dev, ABS_TOOL_WIDTH, state->width);
 151                 }
 152         }
 153         input_mt_report_pointer_emulation(dev, true);
 154
 155         input_report_key(psmouse->dev, BTN_LEFT, state->pressed);
 156         input_sync(psmouse->dev);
 157 }
 158
 159 static void focaltech_process_touch_packet(struct psmouse *psmouse,
 160                                            unsigned char *packet)
 161 {
 162         struct focaltech_data *priv = psmouse->private;
 163         struct focaltech_hw_state *state = &priv->state;
 164         unsigned char fingers = packet[1];
 165         int i;
 166
 167         state->pressed = (packet[0] >> 4) & 1;
 168
 169         /* the second byte contains a bitmap of all fingers touching the pad */
 170         for (i = 0; i < FOC_MAX_FINGERS; i++) {
 171                 state->fingers[i].active = fingers & 0x1;
 172                 if (!state->fingers[i].active) {
 173                         /*
 174                          * Even when the finger becomes active again, we still
 175                          * will have to wait for the first valid position.
 176                          */
 177                         state->fingers[i].valid = false;
 178                 }
 179                 fingers >>= 1;
 180         }
 181 }
 182
 183 static void focaltech_process_abs_packet(struct psmouse *psmouse,
 184                                          unsigned char *packet)
 185 {
 186         struct focaltech_data *priv = psmouse->private;
 187         struct focaltech_hw_state *state = &priv->state;
 188         unsigned int finger;
 189
 190         finger = (packet[1] >> 4) - 1;
 191         if (finger >= FOC_MAX_FINGERS) {
 192                 psmouse_err(psmouse, "Invalid finger in abs packet: %d\n",
 193                             finger);
 194                 return;
 195         }
 196
 197         state->pressed = (packet[0] >> 4) & 1;
 198
 199         state->fingers[finger].x = ((packet[1] & 0xf) << 8) | packet[2];
 200         state->fingers[finger].y = (packet[3] << 8) | packet[4];
 201         state->width = packet[5] >> 4;
 202         state->fingers[finger].valid = true;
 203 }
 204
 205 static void focaltech_process_rel_packet(struct psmouse *psmouse,
 206                                          unsigned char *packet)
 207 {
 208         struct focaltech_data *priv = psmouse->private;
 209         struct focaltech_hw_state *state = &priv->state;
 210         int finger1, finger2;
 211
 212         state->pressed = packet[0] >> 7;
 213         finger1 = ((packet[0] >> 4) & 0x7) - 1;
 214         if (finger1 < FOC_MAX_FINGERS) {
 215                 state->fingers[finger1].x += (char)packet[1];
 216                 state->fingers[finger1].y += (char)packet[2];
 217         } else {
 218                 psmouse_err(psmouse, "First finger in rel packet invalid: %d\n",
 219                             finger1);
 220         }
 221
 222         /*
 223          * If there is an odd number of fingers, the last relative
 224          * packet only contains one finger. In this case, the second
 225          * finger index in the packet is 0 (we subtract 1 in the lines
 226          * above to create array indices, so the finger will overflow
 227          * and be above FOC_MAX_FINGERS).
 228          */
 229         finger2 = ((packet[3] >> 4) & 0x7) - 1;
 230         if (finger2 < FOC_MAX_FINGERS) {
 231                 state->fingers[finger2].x += (char)packet[4];
 232                 state->fingers[finger2].y += (char)packet[5];
 233         }
 234 }
 235
 236 static void focaltech_process_packet(struct psmouse *psmouse)
 237 {
 238         unsigned char *packet = psmouse->packet;
 239
 240         switch (packet[0] & 0xf) {
 241         case FOC_TOUCH:
 242                 focaltech_process_touch_packet(psmouse, packet);
 243                 break;
 244
 245         case FOC_ABS:
 246                 focaltech_process_abs_packet(psmouse, packet);
 247                 break;
 248
 249         case FOC_REL:
 250                 focaltech_process_rel_packet(psmouse, packet);
 251                 break;
 252
 253         default:
 254                 psmouse_err(psmouse, "Unknown packet type: %02x\n", packet[0]);
 255                 break;
 256         }
 257
 258         focaltech_report_state(psmouse);
 259 }
 260
 261 static psmouse_ret_t focaltech_process_byte(struct psmouse *psmouse)
 262 {
 263         if (psmouse->pktcnt >= 6) { /* Full packet received */
 264                 focaltech_process_packet(psmouse);
 265                 return PSMOUSE_FULL_PACKET;
 266         }
 267
 268         /*
 269          * We might want to do some validation of the data here, but
 270          * we do not know the protocol well enough
 271          */
 272         return PSMOUSE_GOOD_DATA;
 273 }
 274
 275 static int focaltech_switch_protocol(struct psmouse *psmouse)
 276 {
 277         struct ps2dev *ps2dev = &psmouse->ps2dev;
 278         unsigned char param[3];
 279
 280         param[0] = 0;
 281         if (ps2_command(ps2dev, param, 0x10f8))
 282                 return -EIO;
 283
 284         if (ps2_command(ps2dev, param, 0x10f8))
 285                 return -EIO;
 286
 287         if (ps2_command(ps2dev, param, 0x10f8))
 288                 return -EIO;
 289
 290         param[0] = 1;
 291         if (ps2_command(ps2dev, param, 0x10f8))
 292                 return -EIO;
 293
 294         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
 295                 return -EIO;
 296
 297         if (ps2_command(ps2dev, param, PSMOUSE_CMD_ENABLE))
 298                 return -EIO;
 299
 300         return 0;
 301 }
 302
 303 static void focaltech_disconnect(struct psmouse *psmouse)
 304 {
 305         focaltech_reset(psmouse);
 306         kfree(psmouse->private);
 307         psmouse->private = NULL;
 308 }
 309
 310 static int focaltech_reconnect(struct psmouse *psmouse)
 311 {
 312         int error;
 313
 314         focaltech_reset(psmouse);
 315
 316         error = focaltech_switch_protocol(psmouse);
 317         if (error) {
 318                 psmouse_err(psmouse, "Unable to initialize the device\n");
 319                 return error;
 320         }
 321
 322         return 0;
 323 }
 324
 325 static void focaltech_set_input_params(struct psmouse *psmouse)
 326 {
 327         struct input_dev *dev = psmouse->dev;
 328         struct focaltech_data *priv = psmouse->private;
 329
 330         /*
 331          * Undo part of setup done for us by psmouse core since touchpad
 332          * is not a relative device.
 333          */
 334         __clear_bit(EV_REL, dev->evbit);
 335         __clear_bit(REL_X, dev->relbit);
 336         __clear_bit(REL_Y, dev->relbit);
 337         __clear_bit(BTN_RIGHT, dev->keybit);
 338         __clear_bit(BTN_MIDDLE, dev->keybit);
 339
 340         /*
 341          * Now set up our capabilities.
 342          */
 343         __set_bit(EV_ABS, dev->evbit);
 344         input_set_abs_params(dev, ABS_MT_POSITION_X, 0, priv->x_max, 0, 0);
 345         input_set_abs_params(dev, ABS_MT_POSITION_Y, 0, priv->y_max, 0, 0);
 346         input_set_abs_params(dev, ABS_TOOL_WIDTH, 0, 15, 0, 0);
 347         input_mt_init_slots(dev, 5, INPUT_MT_POINTER);
 348         __set_bit(INPUT_PROP_BUTTONPAD, dev->propbit);
 349 }
 350
 351 static int focaltech_read_register(struct ps2dev *ps2dev, int reg,
 352                                    unsigned char *param)
 353 {
 354         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
 355                 return -EIO;
 356
 357         param[0] = 0;
 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         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 365                 return -EIO;
 366
 367         param[0] = reg;
 368         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETRES))
 369                 return -EIO;
 370
 371         if (ps2_command(ps2dev, param, PSMOUSE_CMD_GETINFO))
 372                 return -EIO;
 373
 374         return 0;
 375 }
 376
 377 static int focaltech_read_size(struct psmouse *psmouse)
 378 {
 379         struct ps2dev *ps2dev = &psmouse->ps2dev;
 380         struct focaltech_data *priv = psmouse->private;
 381         char param[3];
 382
 383         if (focaltech_read_register(ps2dev, 2, param))
 384                 return -EIO;
 385
 386         /* not sure whether this is 100% correct */
 387         priv->x_max = (unsigned char)param[1] * 128;
 388         priv->y_max = (unsigned char)param[2] * 128;
 389
 390         return 0;
 391 }
 392
 393 void focaltech_set_resolution(struct psmouse *psmouse, unsigned int resolution)
 394 {
 395         /* not supported yet */
 396 }
 397
 398 static void focaltech_set_rate(struct psmouse *psmouse, unsigned int rate)
 399 {
 400         /* not supported yet */
 401 }
 402
 403 static void focaltech_set_scale(struct psmouse *psmouse,
 404                                 enum psmouse_scale scale)
 405 {
 406         /* not supported yet */
 407 }
 408
 409 int focaltech_init(struct psmouse *psmouse)
 410 {
 411         struct focaltech_data *priv;
 412         int error;
 413
 414         psmouse->private = priv = kzalloc(sizeof(struct focaltech_data),
 415                                           GFP_KERNEL);
 416         if (!priv)
 417                 return -ENOMEM;
 418
 419         focaltech_reset(psmouse);
 420
 421         error = focaltech_read_size(psmouse);
 422         if (error) {
 423                 psmouse_err(psmouse,
 424                             "Unable to read the size of the touchpad\n");
 425                 goto fail;
 426         }
 427
 428         error = focaltech_switch_protocol(psmouse);
 429         if (error) {
 430                 psmouse_err(psmouse, "Unable to initialize the device\n");
 431                 goto fail;
 432         }
 433
 434         focaltech_set_input_params(psmouse);
 435
 436         psmouse->protocol_handler = focaltech_process_byte;
 437         psmouse->pktsize = 6;
 438         psmouse->disconnect = focaltech_disconnect;
 439         psmouse->reconnect = focaltech_reconnect;
 440         psmouse->cleanup = focaltech_reset;
 441         /* resync is not supported yet */
 442         psmouse->resync_time = 0;
 443         /*
 444          * rate/resolution/scale changes are not supported yet, and
 445          * the generic implementations of these functions seem to
 446          * confuse some touchpads
 447          */
 448         psmouse->set_resolution = focaltech_set_resolution;
 449         psmouse->set_rate = focaltech_set_rate;
 450         psmouse->set_scale = focaltech_set_scale;
 451
 452         return 0;
 453
 454 fail:
 455         focaltech_reset(psmouse);
 456         kfree(priv);
 457         return error;
 458 }
 459
 460 #else /* CONFIG_MOUSE_PS2_FOCALTECH */
 461
 462 int focaltech_init(struct psmouse *psmouse)
 463 {
 464         focaltech_reset(psmouse);
 465
 466         return 0;
 467 }
 468
 469 #endif /* CONFIG_MOUSE_PS2_FOCALTECH */