drivers/input/mouse/trackpoint.c

   1 /*
   2  * Stephen Evanchik <evanchsa@gmail.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 as published by
   6  * the Free Software Foundation.
   7  *
   8  * Trademarks are the property of their respective owners.
   9  */
  10
  11 #include <linux/slab.h>
  12 #include <linux/delay.h>
  13 #include <linux/serio.h>
  14 #include <linux/module.h>
  15 #include <linux/input.h>
  16 #include <linux/libps2.h>
  17 #include <linux/proc_fs.h>
  18 #include <linux/uaccess.h>
  19 #include "psmouse.h"
  20 #include "trackpoint.h"
  21
  22 static const char * const trackpoint_variants[] = {
  23         [TP_VARIANT_IBM]        = "IBM",
  24         [TP_VARIANT_ALPS]       = "ALPS",
  25         [TP_VARIANT_ELAN]       = "Elan",
  26         [TP_VARIANT_NXP]        = "NXP",
  27 };
  28
  29 /*
  30  * Power-on Reset: Resets all trackpoint parameters, including RAM values,
  31  * to defaults.
  32  * Returns zero on success, non-zero on failure.
  33  */
  34 static int trackpoint_power_on_reset(struct ps2dev *ps2dev)
  35 {
  36         u8 results[2];
  37         int tries = 0;
  38
  39         /* Issue POR command, and repeat up to once if 0xFC00 received */
  40         do {
  41                 if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
  42                     ps2_command(ps2dev, results, MAKE_PS2_CMD(0, 2, TP_POR)))
  43                         return -1;
  44         } while (results[0] == 0xFC && results[1] == 0x00 && ++tries < 2);
  45
  46         /* Check for success response -- 0xAA00 */
  47         if (results[0] != 0xAA || results[1] != 0x00)
  48                 return -ENODEV;
  49
  50         return 0;
  51 }
  52
  53 /*
  54  * Device IO: read, write and toggle bit
  55  */
  56 static int trackpoint_read(struct ps2dev *ps2dev, u8 loc, u8 *results)
  57 {
  58         if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
  59             ps2_command(ps2dev, results, MAKE_PS2_CMD(0, 1, loc))) {
  60                 return -1;
  61         }
  62
  63         return 0;
  64 }
  65
  66 static int trackpoint_write(struct ps2dev *ps2dev, u8 loc, u8 val)
  67 {
  68         if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
  69             ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_WRITE_MEM)) ||
  70             ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, loc)) ||
  71             ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, val))) {
  72                 return -1;
  73         }
  74
  75         return 0;
  76 }
  77
  78 static int trackpoint_toggle_bit(struct ps2dev *ps2dev, u8 loc, u8 mask)
  79 {
  80         /* Bad things will happen if the loc param isn't in this range */
  81         if (loc < 0x20 || loc >= 0x2F)
  82                 return -1;
  83
  84         if (ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_COMMAND)) ||
  85             ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, TP_TOGGLE)) ||
  86             ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, loc)) ||
  87             ps2_command(ps2dev, NULL, MAKE_PS2_CMD(0, 0, mask))) {
  88                 return -1;
  89         }
  90
  91         return 0;
  92 }
  93
  94 static int trackpoint_update_bit(struct ps2dev *ps2dev,
  95                                  u8 loc, u8 mask, u8 value)
  96 {
  97         int retval = 0;
  98         u8 data;
  99
 100         trackpoint_read(ps2dev, loc, &data);
 101         if (((data & mask) == mask) != !!value)
 102                 retval = trackpoint_toggle_bit(ps2dev, loc, mask);
 103
 104         return retval;
 105 }
 106
 107 /*
 108  * Trackpoint-specific attributes
 109  */
 110 struct trackpoint_attr_data {
 111         size_t field_offset;
 112         u8 command;
 113         u8 mask;
 114         bool inverted;
 115         u8 power_on_default;
 116 };
 117
 118 static ssize_t trackpoint_show_int_attr(struct psmouse *psmouse,
 119                                         void *data, char *buf)
 120 {
 121         struct trackpoint_data *tp = psmouse->private;
 122         struct trackpoint_attr_data *attr = data;
 123         u8 value = *(u8 *)((void *)tp + attr->field_offset);
 124
 125         if (attr->inverted)
 126                 value = !value;
 127
 128         return sprintf(buf, "%u\n", value);
 129 }
 130
 131 static ssize_t trackpoint_set_int_attr(struct psmouse *psmouse, void *data,
 132                                         const char *buf, size_t count)
 133 {
 134         struct trackpoint_data *tp = psmouse->private;
 135         struct trackpoint_attr_data *attr = data;
 136         u8 *field = (void *)tp + attr->field_offset;
 137         u8 value;
 138         int err;
 139
 140         err = kstrtou8(buf, 10, &value);
 141         if (err)
 142                 return err;
 143
 144         *field = value;
 145         trackpoint_write(&psmouse->ps2dev, attr->command, value);
 146
 147         return count;
 148 }
 149
 150 #define TRACKPOINT_INT_ATTR(_name, _command, _default)                          \
 151         static struct trackpoint_attr_data trackpoint_attr_##_name = {          \
 152                 .field_offset = offsetof(struct trackpoint_data, _name),        \
 153                 .command = _command,                                            \
 154                 .power_on_default = _default,                                   \
 155         };                                                                      \
 156         PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,                           \
 157                             &trackpoint_attr_##_name,                           \
 158                             trackpoint_show_int_attr, trackpoint_set_int_attr)
 159
 160 static ssize_t trackpoint_set_bit_attr(struct psmouse *psmouse, void *data,
 161                                         const char *buf, size_t count)
 162 {
 163         struct trackpoint_data *tp = psmouse->private;
 164         struct trackpoint_attr_data *attr = data;
 165         bool *field = (void *)tp + attr->field_offset;
 166         bool value;
 167         int err;
 168
 169         err = kstrtobool(buf, &value);
 170         if (err)
 171                 return err;
 172
 173         if (attr->inverted)
 174                 value = !value;
 175
 176         if (*field != value) {
 177                 *field = value;
 178                 trackpoint_toggle_bit(&psmouse->ps2dev, attr->command, attr->mask);
 179         }
 180
 181         return count;
 182 }
 183
 184
 185 #define TRACKPOINT_BIT_ATTR(_name, _command, _mask, _inv, _default)     \
 186 static struct trackpoint_attr_data trackpoint_attr_##_name = {          \
 187         .field_offset           = offsetof(struct trackpoint_data,      \
 188                                            _name),                      \
 189         .command                = _command,                             \
 190         .mask                   = _mask,                                \
 191         .inverted               = _inv,                                 \
 192         .power_on_default       = _default,                             \
 193         };                                                              \
 194 PSMOUSE_DEFINE_ATTR(_name, S_IWUSR | S_IRUGO,                           \
 195                     &trackpoint_attr_##_name,                           \
 196                     trackpoint_show_int_attr, trackpoint_set_bit_attr)
 197
 198 TRACKPOINT_INT_ATTR(sensitivity, TP_SENS, TP_DEF_SENS);
 199 TRACKPOINT_INT_ATTR(speed, TP_SPEED, TP_DEF_SPEED);
 200 TRACKPOINT_INT_ATTR(inertia, TP_INERTIA, TP_DEF_INERTIA);
 201 TRACKPOINT_INT_ATTR(reach, TP_REACH, TP_DEF_REACH);
 202 TRACKPOINT_INT_ATTR(draghys, TP_DRAGHYS, TP_DEF_DRAGHYS);
 203 TRACKPOINT_INT_ATTR(mindrag, TP_MINDRAG, TP_DEF_MINDRAG);
 204 TRACKPOINT_INT_ATTR(thresh, TP_THRESH, TP_DEF_THRESH);
 205 TRACKPOINT_INT_ATTR(upthresh, TP_UP_THRESH, TP_DEF_UP_THRESH);
 206 TRACKPOINT_INT_ATTR(ztime, TP_Z_TIME, TP_DEF_Z_TIME);
 207 TRACKPOINT_INT_ATTR(jenks, TP_JENKS_CURV, TP_DEF_JENKS_CURV);
 208 TRACKPOINT_INT_ATTR(drift_time, TP_DRIFT_TIME, TP_DEF_DRIFT_TIME);
 209
 210 TRACKPOINT_BIT_ATTR(press_to_select, TP_TOGGLE_PTSON, TP_MASK_PTSON, false,
 211                     TP_DEF_PTSON);
 212 TRACKPOINT_BIT_ATTR(skipback, TP_TOGGLE_SKIPBACK, TP_MASK_SKIPBACK, false,
 213                     TP_DEF_SKIPBACK);
 214 TRACKPOINT_BIT_ATTR(ext_dev, TP_TOGGLE_EXT_DEV, TP_MASK_EXT_DEV, true,
 215                     TP_DEF_EXT_DEV);
 216
 217 static bool trackpoint_is_attr_available(struct psmouse *psmouse,
 218                                          struct attribute *attr)
 219 {
 220         struct trackpoint_data *tp = psmouse->private;
 221
 222         return tp->variant_id == TP_VARIANT_IBM ||
 223                 attr == &psmouse_attr_sensitivity.dattr.attr ||
 224                 attr == &psmouse_attr_press_to_select.dattr.attr;
 225 }
 226
 227 static umode_t trackpoint_is_attr_visible(struct kobject *kobj,
 228                                           struct attribute *attr, int n)
 229 {
 230         struct device *dev = container_of(kobj, struct device, kobj);
 231         struct serio *serio = to_serio_port(dev);
 232         struct psmouse *psmouse = serio_get_drvdata(serio);
 233
 234         return trackpoint_is_attr_available(psmouse, attr) ? attr->mode : 0;
 235 }
 236
 237 static struct attribute *trackpoint_attrs[] = {
 238         &psmouse_attr_sensitivity.dattr.attr,
 239         &psmouse_attr_speed.dattr.attr,
 240         &psmouse_attr_inertia.dattr.attr,
 241         &psmouse_attr_reach.dattr.attr,
 242         &psmouse_attr_draghys.dattr.attr,
 243         &psmouse_attr_mindrag.dattr.attr,
 244         &psmouse_attr_thresh.dattr.attr,
 245         &psmouse_attr_upthresh.dattr.attr,
 246         &psmouse_attr_ztime.dattr.attr,
 247         &psmouse_attr_jenks.dattr.attr,
 248         &psmouse_attr_drift_time.dattr.attr,
 249         &psmouse_attr_press_to_select.dattr.attr,
 250         &psmouse_attr_skipback.dattr.attr,
 251         &psmouse_attr_ext_dev.dattr.attr,
 252         NULL
 253 };
 254
 255 static struct attribute_group trackpoint_attr_group = {
 256         .is_visible     = trackpoint_is_attr_visible,
 257         .attrs          = trackpoint_attrs,
 258 };
 259
 260 #define TRACKPOINT_UPDATE(_power_on, _psmouse, _tp, _name)              \
 261 do {                                                                    \
 262         struct trackpoint_attr_data *_attr = &trackpoint_attr_##_name;  \
 263                                                                         \
 264         if ((!_power_on || _tp->_name != _attr->power_on_default) &&    \
 265             trackpoint_is_attr_available(_psmouse,                      \
 266                                 &psmouse_attr_##_name.dattr.attr)) {    \
 267                 if (!_attr->mask)                                       \
 268                         trackpoint_write(&_psmouse->ps2dev,             \
 269                                          _attr->command, _tp->_name);   \
 270                 else                                                    \
 271                         trackpoint_update_bit(&_psmouse->ps2dev,        \
 272                                         _attr->command, _attr->mask,    \
 273                                         _tp->_name);                    \
 274         }                                                               \
 275 } while (0)
 276
 277 #define TRACKPOINT_SET_POWER_ON_DEFAULT(_tp, _name)                     \
 278 do {                                                                    \
 279         _tp->_name = trackpoint_attr_##_name.power_on_default;          \
 280 } while (0)
 281
 282 static int trackpoint_start_protocol(struct psmouse *psmouse,
 283                                      u8 *variant_id, u8 *firmware_id)
 284 {
 285         u8 param[2] = { 0 };
 286         int error;
 287
 288         error = ps2_command(&psmouse->ps2dev,
 289                             param, MAKE_PS2_CMD(0, 2, TP_READ_ID));
 290         if (error)
 291                 return error;
 292
 293         switch (param[0]) {
 294         case TP_VARIANT_IBM:
 295         case TP_VARIANT_ALPS:
 296         case TP_VARIANT_ELAN:
 297         case TP_VARIANT_NXP:
 298                 if (variant_id)
 299                         *variant_id = param[0];
 300                 if (firmware_id)
 301                         *firmware_id = param[1];
 302                 return 0;
 303         }
 304
 305         return -ENODEV;
 306 }
 307
 308 /*
 309  * Write parameters to trackpad.
 310  * in_power_on_state: Set to true if TP is in default / power-on state (ex. if
 311  *                    power-on reset was run). If so, values will only be
 312  *                    written to TP if they differ from power-on default.
 313  */
 314 static int trackpoint_sync(struct psmouse *psmouse, bool in_power_on_state)
 315 {
 316         struct trackpoint_data *tp = psmouse->private;
 317
 318         if (!in_power_on_state && tp->variant_id == TP_VARIANT_IBM) {
 319                 /*
 320                  * Disable features that may make device unusable
 321                  * with this driver.
 322                  */
 323                 trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_TWOHAND,
 324                                       TP_MASK_TWOHAND, TP_DEF_TWOHAND);
 325
 326                 trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_SOURCE_TAG,
 327                                       TP_MASK_SOURCE_TAG, TP_DEF_SOURCE_TAG);
 328
 329                 trackpoint_update_bit(&psmouse->ps2dev, TP_TOGGLE_MB,
 330                                       TP_MASK_MB, TP_DEF_MB);
 331         }
 332
 333         /*
 334          * These properties can be changed in this driver. Only
 335          * configure them if the values are non-default or if the TP is in
 336          * an unknown state.
 337          */
 338         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, sensitivity);
 339         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, inertia);
 340         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, speed);
 341         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, reach);
 342         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, draghys);
 343         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, mindrag);
 344         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, thresh);
 345         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, upthresh);
 346         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ztime);
 347         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, jenks);
 348         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, drift_time);
 349
 350         /* toggles */
 351         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, press_to_select);
 352         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, skipback);
 353         TRACKPOINT_UPDATE(in_power_on_state, psmouse, tp, ext_dev);
 354
 355         return 0;
 356 }
 357
 358 static void trackpoint_defaults(struct trackpoint_data *tp)
 359 {
 360         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, sensitivity);
 361         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, speed);
 362         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, reach);
 363         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, draghys);
 364         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, mindrag);
 365         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, thresh);
 366         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, upthresh);
 367         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ztime);
 368         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, jenks);
 369         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, drift_time);
 370         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, inertia);
 371
 372         /* toggles */
 373         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, press_to_select);
 374         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, skipback);
 375         TRACKPOINT_SET_POWER_ON_DEFAULT(tp, ext_dev);
 376 }
 377
 378 static void trackpoint_disconnect(struct psmouse *psmouse)
 379 {
 380         device_remove_group(&psmouse->ps2dev.serio->dev,
 381                             &trackpoint_attr_group);
 382
 383         kfree(psmouse->private);
 384         psmouse->private = NULL;
 385 }
 386
 387 static int trackpoint_reconnect(struct psmouse *psmouse)
 388 {
 389         struct trackpoint_data *tp = psmouse->private;
 390         int error;
 391         bool was_reset;
 392
 393         error = trackpoint_start_protocol(psmouse, NULL, NULL);
 394         if (error)
 395                 return error;
 396
 397         was_reset = tp->variant_id == TP_VARIANT_IBM &&
 398                     trackpoint_power_on_reset(&psmouse->ps2dev) == 0;
 399
 400         error = trackpoint_sync(psmouse, was_reset);
 401         if (error)
 402                 return error;
 403
 404         return 0;
 405 }
 406
 407 int trackpoint_detect(struct psmouse *psmouse, bool set_properties)
 408 {
 409         struct ps2dev *ps2dev = &psmouse->ps2dev;
 410         struct trackpoint_data *tp;
 411         u8 variant_id;
 412         u8 firmware_id;
 413         u8 button_info;
 414         int error;
 415
 416         error = trackpoint_start_protocol(psmouse, &variant_id, &firmware_id);
 417         if (error)
 418                 return error;
 419
 420         if (!set_properties)
 421                 return 0;
 422
 423         tp = kzalloc(sizeof(*tp), GFP_KERNEL);
 424         if (!tp)
 425                 return -ENOMEM;
 426
 427         trackpoint_defaults(tp);
 428         tp->variant_id = variant_id;
 429         tp->firmware_id = firmware_id;
 430
 431         psmouse->private = tp;
 432
 433         psmouse->vendor = trackpoint_variants[variant_id];
 434         psmouse->name = "TrackPoint";
 435
 436         psmouse->reconnect = trackpoint_reconnect;
 437         psmouse->disconnect = trackpoint_disconnect;
 438
 439         if (variant_id != TP_VARIANT_IBM) {
 440                 /* Newer variants do not support extended button query. */
 441                 button_info = 0x33;
 442         } else {
 443                 error = trackpoint_read(ps2dev, TP_EXT_BTN, &button_info);
 444                 if (error) {
 445                         psmouse_warn(psmouse,
 446                                      "failed to get extended button data, assuming 3 buttons\n");
 447                         button_info = 0x33;
 448                 } else if (!button_info) {
 449                         psmouse_warn(psmouse,
 450                                      "got 0 in extended button data, assuming 3 buttons\n");
 451                         button_info = 0x33;
 452                 }
 453         }
 454
 455         if ((button_info & 0x0f) >= 3)
 456                 input_set_capability(psmouse->dev, EV_KEY, BTN_MIDDLE);
 457
 458         __set_bit(INPUT_PROP_POINTER, psmouse->dev->propbit);
 459         __set_bit(INPUT_PROP_POINTING_STICK, psmouse->dev->propbit);
 460
 461         if (variant_id != TP_VARIANT_IBM ||
 462             trackpoint_power_on_reset(ps2dev) != 0) {
 463                 /*
 464                  * Write defaults to TP if we did not reset the trackpoint.
 465                  */
 466                 trackpoint_sync(psmouse, false);
 467         }
 468
 469         error = device_add_group(&ps2dev->serio->dev, &trackpoint_attr_group);
 470         if (error) {
 471                 psmouse_err(psmouse,
 472                             "failed to create sysfs attributes, error: %d\n",
 473                             error);
 474                 kfree(psmouse->private);
 475                 psmouse->private = NULL;
 476                 return -1;
 477         }
 478
 479         psmouse_info(psmouse,
 480                      "%s TrackPoint firmware: 0x%02x, buttons: %d/%d\n",
 481                      psmouse->vendor, firmware_id,
 482                      (button_info & 0xf0) >> 4, button_info & 0x0f);
 483
 484         return 0;
 485 }
 486