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 = "Touchpad";
  47         }
  48
  49         return 0;
  50 }
  51
  52 #ifdef CONFIG_MOUSE_PS2_FOCALTECH
  53
  54 /*
  55  * Packet types - the numbers are not consecutive, so we might be missing
  56  * something here.
  57  */
  58 #define FOC_TOUCH 0x3 /* bitmap of active fingers */
  59 #define FOC_ABS 0x6 /* absolute position of one finger */
  60 #define FOC_REL 0x9 /* relative position of 1-2 fingers */
  61
  62 #define FOC_MAX_FINGERS 5
  63
  64 /*
  65  * Current state of a single finger on the touchpad.
  66  */
  67 struct focaltech_finger_state {
  68         /* The touchpad has generated a touch event for the finger */
  69         bool active;
  70
  71         /*
  72          * The touchpad has sent position data for the finger. The
  73          * flag is 0 when the finger is not active, and there is a
  74          * time between the first touch event for the finger and the
  75          * following absolute position packet for the finger where the
  76          * touchpad has declared the finger to be valid, but we do not
  77          * have any valid position yet.
  78          */
  79         bool valid;
  80
  81         /*
  82          * Absolute position (from the bottom left corner) of the
  83          * finger.
  84          */
  85         unsigned int x;
  86         unsigned int y;
  87 };
  88
  89 /*
  90  * Description of the current state of the touchpad hardware.
  91  */
  92 struct focaltech_hw_state {
  93         /*
  94          * The touchpad tracks the positions of the fingers for us,
  95          * the array indices correspond to the finger indices returned
  96          * in the report packages.
  97          */
  98         struct focaltech_finger_state fingers[FOC_MAX_FINGERS];
  99
 100         /*
 101          * Finger width 0-7 and 15 for a very big contact area.
 102          * 15 value stays until the finger is released.
 103          * Width is reported only in absolute packets.
 104          * Since hardware reports width only for last touching finger,
 105          * there is no need to store width for every specific finger,
 106          * so we keep only last value reported.
 107          */
 108         unsigned int width;
 109
 110         /* True if the clickpad has been pressed. */
 111         bool pressed;
 112 };
 113
 114 struct focaltech_data {
 115         unsigned int x_max, y_max;
 116         struct focaltech_hw_state state;
 117 };
 118
 119 static void focaltech_report_state(struct psmouse *psmouse)
 120 {
 121         struct focaltech_data *priv = psmouse->private;
 122         struct focaltech_hw_state *state = &priv->state;
 123         struct input_dev *dev = psmouse->dev;
 124         int i;
 125
 126         for (i = 0; i < FOC_MAX_FINGERS; i++) {
 127                 struct focaltech_finger_state *finger = &state->fingers[i];
 128                 bool active = finger->active && finger->valid;
 129
 130                 input_mt_slot(dev, i);
 131                 input_mt_report_slot_state(dev, MT_TOOL_FINGER, active);
 132                 if (active) {
 133                         unsigned int clamped_x, clamped_y;
 134                         /*
 135                          * The touchpad might report invalid data, so we clamp
 136                          * the resulting values so that we do not confuse
 137                          * userspace.
 138                          */
 139                         clamped_x = clamp(finger->x, 0U, priv->x_max);
 140                         clamped_y = clamp(finger->y, 0U, priv->y_max);
 141                         input_report_abs(dev, ABS_MT_POSITION_X, clamped_x);
 142                         input_report_abs(dev, ABS_MT_POSITION_Y,
 143                                          priv->y_max - clamped_y);
 144                         input_report_abs(dev, ABS_TOOL_WIDTH, state->width);
 145                 }
 146         }
 147         input_mt_report_pointer_emulation(dev, true);
 148
 149         input_report_key(dev, BTN_LEFT, state->pressed);
 150         input_sync(dev);
 151 }
 152
 153 static void focaltech_process_touch_packet(struct psmouse *psmouse,
 154                                            unsigned char *packet)
 155 {
 156         struct focaltech_data *priv = psmouse->private;
 157         struct focaltech_hw_state *state = &priv->state;
 158         unsigned char fingers = packet[1];
 159         int i;
 160
 161         state->pressed = (packet[0] >> 4) & 1;
 162
 163         /* the second byte contains a bitmap of all fingers touching the pad */
 164         for (i = 0; i < FOC_MAX_FINGERS; i++) {
 165                 state->fingers[i].active = fingers & 0x1;
 166                 if (!state->fingers[i].active) {
 167                         /*
 168                          * Even when the finger becomes active again, we still
 169                          * will have to wait for the first valid position.
 170                          */
 171                         state->fingers[i].valid = false;
 172                 }
 173                 fingers >>= 1;
 174         }
 175 }
 176
 177 static void focaltech_process_abs_packet(struct psmouse *psmouse,
 178                                          unsigned char *packet)
 179 {
 180         struct focaltech_data *priv = psmouse->private;
 181         struct focaltech_hw_state *state = &priv->state;
 182         unsigned int finger;
 183
 184         finger = (packet[1] >> 4) - 1;
 185         if (finger >= FOC_MAX_FINGERS) {
 186                 psmouse_err(psmouse, "Invalid finger in abs packet: %d\n",
 187                             finger);
 188                 return;
 189         }
 190
 191         state->pressed = (packet[0] >> 4) & 1;
 192
 193         state->fingers[finger].x = ((packet[1] & 0xf) << 8) | packet[2];
 194         state->fingers[finger].y = (packet[3] << 8) | packet[4];
 195         state->width = packet[5] >> 4;
 196         state->fingers[finger].valid = true;
 197 }
 198
 199 static void focaltech_process_rel_packet(struct psmouse *psmouse,
 200                                          unsigned char *packet)
 201 {
 202         struct focaltech_data *priv = psmouse->private;
 203         struct focaltech_hw_state *state = &priv->state;
 204         int finger1, finger2;
 205
 206         state->pressed = packet[0] >> 7;
 207         finger1 = ((packet[0] >> 4) & 0x7) - 1;
 208         if (finger1 < FOC_MAX_FINGERS) {
 209                 state->fingers[finger1].x += (char)packet[1];
 210                 state->fingers[finger1].y += (char)packet[2];
 211         } else {
 212                 psmouse_err(psmouse, "First finger in rel packet invalid: %d\n",
 213                             finger1);
 214         }
 215
 216         /*
 217          * If there is an odd number of fingers, the last relative
 218          * packet only contains one finger. In this case, the second
 219          * finger index in the packet is 0 (we subtract 1 in the lines
 220          * above to create array indices, so the finger will overflow
 221          * and be above FOC_MAX_FINGERS).
 222          */
 223         finger2 = ((packet[3] >> 4) & 0x7) - 1;
 224         if (finger2 < FOC_MAX_FINGERS) {
 225                 state->fingers[finger2].x += (char)packet[4];
 226                 state->fingers[finger2].y += (char)packet[5];
 227         }
 228 }
 229
 230 static void focaltech_process_packet(struct psmouse *psmouse)
 231 {
 232         unsigned char *packet = psmouse->packet;
 233
 234         switch (packet[0] & 0xf) {
 235         case FOC_TOUCH:
 236                 focaltech_process_touch_packet(psmouse, packet);
 237                 break;
 238
 239         case FOC_ABS:
 240                 focaltech_process_abs_packet(psmouse, packet);
 241                 break;
 242
 243         case FOC_REL:
 244                 focaltech_process_rel_packet(psmouse, packet);
 245                 break;
 246
 247         default:
 248                 psmouse_err(psmouse, "Unknown packet type: %02x\n", packet[0]);
 249                 break;
 250         }
 251
 252         focaltech_report_state(psmouse);
 253 }
 254
 255 static psmouse_ret_t focaltech_process_byte(struct psmouse *psmouse)
 256 {
 257         if (psmouse->pktcnt >= 6) { /* Full packet received */
 258                 focaltech_process_packet(psmouse);
 259                 return PSMOUSE_FULL_PACKET;
 260         }
 261
 262         /*
 263          * We might want to do some validation of the data here, but
 264          * we do not know the protocol well enough
 265          */
 266         return PSMOUSE_GOOD_DATA;
 267 }
 268
 269 static int focaltech_switch_protocol(struct psmouse *psmouse)
 270 {
 271         struct ps2dev *ps2dev = &psmouse->ps2dev;
 272         unsigned char param[3];
 273
 274         param[0] = 0;
 275         if (ps2_command(ps2dev, param, 0x10f8))
 276                 return -EIO;
 277
 278         if (ps2_command(ps2dev, param, 0x10f8))
 279                 return -EIO;
 280
 281         if (ps2_command(ps2dev, param, 0x10f8))
 282                 return -EIO;
 283
 284         param[0] = 1;
 285         if (ps2_command(ps2dev, param, 0x10f8))
 286                 return -EIO;
 287
 288         if (ps2_command(ps2dev, param, PSMOUSE_CMD_SETSCALE11))
 289                 return -EIO;
 290
 291         if (ps2_command(ps2dev, param, PSMOUSE_CMD_ENABLE))
 292                 return -EIO;
 293
 294         return 0;
 295 }
 296
 297 static void focaltech_reset(struct psmouse *psmouse)
 298 {
 299         ps2_command(&psmouse->ps2dev, NULL, PSMOUSE_CMD_RESET_DIS);
 300         psmouse_reset(psmouse);
 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 static void focaltech_set_resolution(struct psmouse *psmouse,
 394                                      unsigned int resolution)
 395 {
 396         /* not supported yet */
 397 }
 398
 399 static void focaltech_set_rate(struct psmouse *psmouse, unsigned int rate)
 400 {
 401         /* not supported yet */
 402 }
 403
 404 static void focaltech_set_scale(struct psmouse *psmouse,
 405                                 enum psmouse_scale scale)
 406 {
 407         /* not supported yet */
 408 }
 409
 410 int focaltech_init(struct psmouse *psmouse)
 411 {
 412         struct focaltech_data *priv;
 413         int error;
 414
 415         psmouse->private = priv = kzalloc(sizeof(struct focaltech_data),
 416                                           GFP_KERNEL);
 417         if (!priv)
 418                 return -ENOMEM;
 419
 420         focaltech_reset(psmouse);
 421
 422         error = focaltech_read_size(psmouse);
 423         if (error) {
 424                 psmouse_err(psmouse,
 425                             "Unable to read the size of the touchpad\n");
 426                 goto fail;
 427         }
 428
 429         error = focaltech_switch_protocol(psmouse);
 430         if (error) {
 431                 psmouse_err(psmouse, "Unable to initialize the device\n");
 432                 goto fail;
 433         }
 434
 435         focaltech_set_input_params(psmouse);
 436
 437         psmouse->protocol_handler = focaltech_process_byte;
 438         psmouse->pktsize = 6;
 439         psmouse->disconnect = focaltech_disconnect;
 440         psmouse->reconnect = focaltech_reconnect;
 441         psmouse->cleanup = focaltech_reset;
 442         /* resync is not supported yet */
 443         psmouse->resync_time = 0;
 444         /*
 445          * rate/resolution/scale changes are not supported yet, and
 446          * the generic implementations of these functions seem to
 447          * confuse some touchpads
 448          */
 449         psmouse->set_resolution = focaltech_set_resolution;
 450         psmouse->set_rate = focaltech_set_rate;
 451         psmouse->set_scale = focaltech_set_scale;
 452
 453         return 0;
 454
 455 fail:
 456         focaltech_reset(psmouse);
 457         kfree(priv);
 458         return error;
 459 }
 460 #endif /* CONFIG_MOUSE_PS2_FOCALTECH */