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