drivers/iio/common/hid-sensors/hid-sensor-attributes.c

   1 /*
   2  * HID Sensors Driver
   3  * Copyright (c) 2012, Intel Corporation.
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms and conditions of the GNU General Public License,
   7  * version 2, as published by the Free Software Foundation.
   8  *
   9  * This program is distributed in the hope it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  12  * more details.
  13  *
  14  * You should have received a copy of the GNU General Public License along with
  15  * this program; if not, write to the Free Software Foundation, Inc.,
  16  * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  */
  19 #include <linux/device.h>
  20 #include <linux/platform_device.h>
  21 #include <linux/module.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/irq.h>
  24 #include <linux/slab.h>
  25 #include <linux/hid-sensor-hub.h>
  26 #include <linux/iio/iio.h>
  27 #include <linux/iio/sysfs.h>
  28
  29 static struct {
  30         u32 usage_id;
  31         int unit; /* 0 for default others from HID sensor spec */
  32         int scale_val0; /* scale, whole number */
  33         int scale_val1; /* scale, fraction in nanos */
  34 } unit_conversion[] = {
  35         {HID_USAGE_SENSOR_ACCEL_3D, 0, 9, 806650000},
  36         {HID_USAGE_SENSOR_ACCEL_3D,
  37                 HID_USAGE_SENSOR_UNITS_METERS_PER_SEC_SQRD, 1, 0},
  38         {HID_USAGE_SENSOR_ACCEL_3D,
  39                 HID_USAGE_SENSOR_UNITS_G, 9, 806650000},
  40
  41         {HID_USAGE_SENSOR_GYRO_3D, 0, 0, 17453293},
  42         {HID_USAGE_SENSOR_GYRO_3D,
  43                 HID_USAGE_SENSOR_UNITS_RADIANS_PER_SECOND, 1, 0},
  44         {HID_USAGE_SENSOR_GYRO_3D,
  45                 HID_USAGE_SENSOR_UNITS_DEGREES_PER_SECOND, 0, 17453293},
  46
  47         {HID_USAGE_SENSOR_COMPASS_3D, 0, 0, 1000000},
  48         {HID_USAGE_SENSOR_COMPASS_3D, HID_USAGE_SENSOR_UNITS_GAUSS, 1, 0},
  49
  50         {HID_USAGE_SENSOR_INCLINOMETER_3D, 0, 0, 17453293},
  51         {HID_USAGE_SENSOR_INCLINOMETER_3D,
  52                 HID_USAGE_SENSOR_UNITS_DEGREES, 0, 17453293},
  53         {HID_USAGE_SENSOR_INCLINOMETER_3D,
  54                 HID_USAGE_SENSOR_UNITS_RADIANS, 1, 0},
  55
  56         {HID_USAGE_SENSOR_ALS, 0, 1, 0},
  57         {HID_USAGE_SENSOR_ALS, HID_USAGE_SENSOR_UNITS_LUX, 1, 0},
  58
  59         {HID_USAGE_SENSOR_PRESSURE, 0, 100, 0},
  60         {HID_USAGE_SENSOR_PRESSURE, HID_USAGE_SENSOR_UNITS_PASCAL, 0, 1000000},
  61
  62         {HID_USAGE_SENSOR_TIME_TIMESTAMP, 0, 1000000000, 0},
  63         {HID_USAGE_SENSOR_TIME_TIMESTAMP, HID_USAGE_SENSOR_UNITS_MILLISECOND,
  64                 1000000, 0},
  65 };
  66
  67 static int pow_10(unsigned power)
  68 {
  69         int i;
  70         int ret = 1;
  71         for (i = 0; i < power; ++i)
  72                 ret = ret * 10;
  73
  74         return ret;
  75 }
  76
  77 static void simple_div(int dividend, int divisor, int *whole,
  78                                 int *micro_frac)
  79 {
  80         int rem;
  81         int exp = 0;
  82
  83         *micro_frac = 0;
  84         if (divisor == 0) {
  85                 *whole = 0;
  86                 return;
  87         }
  88         *whole = dividend/divisor;
  89         rem = dividend % divisor;
  90         if (rem) {
  91                 while (rem <= divisor) {
  92                         rem *= 10;
  93                         exp++;
  94                 }
  95                 *micro_frac = (rem / divisor) * pow_10(6-exp);
  96         }
  97 }
  98
  99 static void split_micro_fraction(unsigned int no, int exp, int *val1, int *val2)
 100 {
 101         *val1 = no/pow_10(exp);
 102         *val2 = no%pow_10(exp) * pow_10(6-exp);
 103 }
 104
 105 /*
 106 VTF format uses exponent and variable size format.
 107 For example if the size is 2 bytes
 108 0x0067 with VTF16E14 format -> +1.03
 109 To convert just change to 0x67 to decimal and use two decimal as E14 stands
 110 for 10^-2.
 111 Negative numbers are 2's complement
 112 */
 113 static void convert_from_vtf_format(u32 value, int size, int exp,
 114                                         int *val1, int *val2)
 115 {
 116         int sign = 1;
 117
 118         if (value & BIT(size*8 - 1)) {
 119                 value =  ((1LL << (size * 8)) - value);
 120                 sign = -1;
 121         }
 122         exp = hid_sensor_convert_exponent(exp);
 123         if (exp >= 0) {
 124                 *val1 = sign * value * pow_10(exp);
 125                 *val2 = 0;
 126         } else {
 127                 split_micro_fraction(value, -exp, val1, val2);
 128                 if (*val1)
 129                         *val1 = sign * (*val1);
 130                 else
 131                         *val2 = sign * (*val2);
 132         }
 133 }
 134
 135 static u32 convert_to_vtf_format(int size, int exp, int val1, int val2)
 136 {
 137         u32 value;
 138         int sign = 1;
 139
 140         if (val1 < 0 || val2 < 0)
 141                 sign = -1;
 142         exp = hid_sensor_convert_exponent(exp);
 143         if (exp < 0) {
 144                 value = abs(val1) * pow_10(-exp);
 145                 value += abs(val2) / pow_10(6+exp);
 146         } else
 147                 value = abs(val1) / pow_10(exp);
 148         if (sign < 0)
 149                 value =  ((1LL << (size * 8)) - value);
 150
 151         return value;
 152 }
 153
 154 s32 hid_sensor_read_poll_value(struct hid_sensor_common *st)
 155 {
 156         s32 value = 0;
 157         int ret;
 158
 159         ret = sensor_hub_get_feature(st->hsdev,
 160                                      st->poll.report_id,
 161                                      st->poll.index, sizeof(value), &value);
 162
 163         if (ret < 0 || value < 0) {
 164                 return -EINVAL;
 165         } else {
 166                 if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
 167                         value = value * 1000;
 168         }
 169
 170         return value;
 171 }
 172 EXPORT_SYMBOL(hid_sensor_read_poll_value);
 173
 174 int hid_sensor_read_samp_freq_value(struct hid_sensor_common *st,
 175                                 int *val1, int *val2)
 176 {
 177         s32 value;
 178         int ret;
 179
 180         ret = sensor_hub_get_feature(st->hsdev,
 181                                      st->poll.report_id,
 182                                      st->poll.index, sizeof(value), &value);
 183         if (ret < 0 || value < 0) {
 184                 *val1 = *val2 = 0;
 185                 return -EINVAL;
 186         } else {
 187                 if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
 188                         simple_div(1000, value, val1, val2);
 189                 else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
 190                         simple_div(1, value, val1, val2);
 191                 else {
 192                         *val1 = *val2 = 0;
 193                         return -EINVAL;
 194                 }
 195         }
 196
 197         return IIO_VAL_INT_PLUS_MICRO;
 198 }
 199 EXPORT_SYMBOL(hid_sensor_read_samp_freq_value);
 200
 201 int hid_sensor_write_samp_freq_value(struct hid_sensor_common *st,
 202                                 int val1, int val2)
 203 {
 204         s32 value;
 205         int ret;
 206
 207         if (val1 < 0 || val2 < 0)
 208                 return -EINVAL;
 209
 210         value = val1 * pow_10(6) + val2;
 211         if (value) {
 212                 if (st->poll.units == HID_USAGE_SENSOR_UNITS_MILLISECOND)
 213                         value = pow_10(9)/value;
 214                 else if (st->poll.units == HID_USAGE_SENSOR_UNITS_SECOND)
 215                         value = pow_10(6)/value;
 216                 else
 217                         value = 0;
 218         }
 219         ret = sensor_hub_set_feature(st->hsdev, st->poll.report_id,
 220                                      st->poll.index, sizeof(value), &value);
 221         if (ret < 0 || value < 0)
 222                 ret = -EINVAL;
 223
 224         return ret;
 225 }
 226 EXPORT_SYMBOL(hid_sensor_write_samp_freq_value);
 227
 228 int hid_sensor_read_raw_hyst_value(struct hid_sensor_common *st,
 229                                 int *val1, int *val2)
 230 {
 231         s32 value;
 232         int ret;
 233
 234         ret = sensor_hub_get_feature(st->hsdev,
 235                                      st->sensitivity.report_id,
 236                                      st->sensitivity.index, sizeof(value),
 237                                      &value);
 238         if (ret < 0 || value < 0) {
 239                 *val1 = *val2 = 0;
 240                 return -EINVAL;
 241         } else {
 242                 convert_from_vtf_format(value, st->sensitivity.size,
 243                                         st->sensitivity.unit_expo,
 244                                         val1, val2);
 245         }
 246
 247         return IIO_VAL_INT_PLUS_MICRO;
 248 }
 249 EXPORT_SYMBOL(hid_sensor_read_raw_hyst_value);
 250
 251 int hid_sensor_write_raw_hyst_value(struct hid_sensor_common *st,
 252                                         int val1, int val2)
 253 {
 254         s32 value;
 255         int ret;
 256
 257         if (val1 < 0 || val2 < 0)
 258                 return -EINVAL;
 259
 260         value = convert_to_vtf_format(st->sensitivity.size,
 261                                 st->sensitivity.unit_expo,
 262                                 val1, val2);
 263         ret = sensor_hub_set_feature(st->hsdev, st->sensitivity.report_id,
 264                                      st->sensitivity.index, sizeof(value),
 265                                      &value);
 266         if (ret < 0 || value < 0)
 267                 ret = -EINVAL;
 268
 269         return ret;
 270 }
 271 EXPORT_SYMBOL(hid_sensor_write_raw_hyst_value);
 272
 273 /*
 274  * This fuction applies the unit exponent to the scale.
 275  * For example:
 276  * 9.806650000 ->exp:2-> val0[980]val1[665000000]
 277  * 9.000806000 ->exp:2-> val0[900]val1[80600000]
 278  * 0.174535293 ->exp:2-> val0[17]val1[453529300]
 279  * 1.001745329 ->exp:0-> val0[1]val1[1745329]
 280  * 1.001745329 ->exp:2-> val0[100]val1[174532900]
 281  * 1.001745329 ->exp:4-> val0[10017]val1[453290000]
 282  * 9.806650000 ->exp:-2-> val0[0]val1[98066500]
 283  */
 284 static void adjust_exponent_nano(int *val0, int *val1, int scale0,
 285                                   int scale1, int exp)
 286 {
 287         int i;
 288         int x;
 289         int res;
 290         int rem;
 291
 292         if (exp > 0) {
 293                 *val0 = scale0 * pow_10(exp);
 294                 res = 0;
 295                 if (exp > 9) {
 296                         *val1 = 0;
 297                         return;
 298                 }
 299                 for (i = 0; i < exp; ++i) {
 300                         x = scale1 / pow_10(8 - i);
 301                         res += (pow_10(exp - 1 - i) * x);
 302                         scale1 = scale1 % pow_10(8 - i);
 303                 }
 304                 *val0 += res;
 305                         *val1 = scale1 * pow_10(exp);
 306         } else if (exp < 0) {
 307                 exp = abs(exp);
 308                 if (exp > 9) {
 309                         *val0 = *val1 = 0;
 310                         return;
 311                 }
 312                 *val0 = scale0 / pow_10(exp);
 313                 rem = scale0 % pow_10(exp);
 314                 res = 0;
 315                 for (i = 0; i < (9 - exp); ++i) {
 316                         x = scale1 / pow_10(8 - i);
 317                         res += (pow_10(8 - exp - i) * x);
 318                         scale1 = scale1 % pow_10(8 - i);
 319                 }
 320                 *val1 = rem * pow_10(9 - exp) + res;
 321         } else {
 322                 *val0 = scale0;
 323                 *val1 = scale1;
 324         }
 325 }
 326
 327 int hid_sensor_format_scale(u32 usage_id,
 328                         struct hid_sensor_hub_attribute_info *attr_info,
 329                         int *val0, int *val1)
 330 {
 331         int i;
 332         int exp;
 333
 334         *val0 = 1;
 335         *val1 = 0;
 336
 337         for (i = 0; i < ARRAY_SIZE(unit_conversion); ++i) {
 338                 if (unit_conversion[i].usage_id == usage_id &&
 339                         unit_conversion[i].unit == attr_info->units) {
 340                         exp  = hid_sensor_convert_exponent(
 341                                                 attr_info->unit_expo);
 342                         adjust_exponent_nano(val0, val1,
 343                                         unit_conversion[i].scale_val0,
 344                                         unit_conversion[i].scale_val1, exp);
 345                         break;
 346                 }
 347         }
 348
 349         return IIO_VAL_INT_PLUS_NANO;
 350 }
 351 EXPORT_SYMBOL(hid_sensor_format_scale);
 352
 353 int64_t hid_sensor_convert_timestamp(struct hid_sensor_common *st,
 354                                      int64_t raw_value)
 355 {
 356         return st->timestamp_ns_scale * raw_value;
 357 }
 358 EXPORT_SYMBOL(hid_sensor_convert_timestamp);
 359
 360 static
 361 int hid_sensor_get_reporting_interval(struct hid_sensor_hub_device *hsdev,
 362                                         u32 usage_id,
 363                                         struct hid_sensor_common *st)
 364 {
 365         sensor_hub_input_get_attribute_info(hsdev,
 366                                         HID_FEATURE_REPORT, usage_id,
 367                                         HID_USAGE_SENSOR_PROP_REPORT_INTERVAL,
 368                                         &st->poll);
 369         /* Default unit of measure is milliseconds */
 370         if (st->poll.units == 0)
 371                 st->poll.units = HID_USAGE_SENSOR_UNITS_MILLISECOND;
 372         return 0;
 373
 374 }
 375
 376 int hid_sensor_parse_common_attributes(struct hid_sensor_hub_device *hsdev,
 377                                         u32 usage_id,
 378                                         struct hid_sensor_common *st)
 379 {
 380
 381         struct hid_sensor_hub_attribute_info timestamp;
 382         s32 value;
 383         int ret;
 384
 385         hid_sensor_get_reporting_interval(hsdev, usage_id, st);
 386
 387         sensor_hub_input_get_attribute_info(hsdev,
 388                                         HID_FEATURE_REPORT, usage_id,
 389                                         HID_USAGE_SENSOR_PROP_REPORT_STATE,
 390                                         &st->report_state);
 391
 392         sensor_hub_input_get_attribute_info(hsdev,
 393                                         HID_FEATURE_REPORT, usage_id,
 394                                         HID_USAGE_SENSOR_PROY_POWER_STATE,
 395                                         &st->power_state);
 396
 397         sensor_hub_input_get_attribute_info(hsdev,
 398                         HID_FEATURE_REPORT, usage_id,
 399                         HID_USAGE_SENSOR_PROP_SENSITIVITY_ABS,
 400                          &st->sensitivity);
 401
 402         sensor_hub_input_get_attribute_info(hsdev,
 403                                             HID_INPUT_REPORT, usage_id,
 404                                             HID_USAGE_SENSOR_TIME_TIMESTAMP,
 405                                             &timestamp);
 406         if (timestamp.index >= 0 && timestamp.report_id) {
 407                 int val0, val1;
 408
 409                 hid_sensor_format_scale(HID_USAGE_SENSOR_TIME_TIMESTAMP,
 410                                         &timestamp, &val0, &val1);
 411                 st->timestamp_ns_scale = val0;
 412         } else
 413                 st->timestamp_ns_scale = 1000000000;
 414
 415         hid_dbg(hsdev->hdev, "common attributes: %x:%x, %x:%x, %x:%x %x:%x %x:%x\n",
 416                 st->poll.index, st->poll.report_id,
 417                 st->report_state.index, st->report_state.report_id,
 418                 st->power_state.index, st->power_state.report_id,
 419                 st->sensitivity.index, st->sensitivity.report_id,
 420                 timestamp.index, timestamp.report_id);
 421
 422         ret = sensor_hub_get_feature(hsdev,
 423                                 st->power_state.report_id,
 424                                 st->power_state.index, sizeof(value), &value);
 425         if (ret < 0)
 426                 return ret;
 427         if (value < 0)
 428                 return -EINVAL;
 429
 430         return 0;
 431 }
 432 EXPORT_SYMBOL(hid_sensor_parse_common_attributes);
 433
 434 MODULE_AUTHOR("Srinivas Pandruvada <srinivas.pandruvada@intel.com>");
 435 MODULE_DESCRIPTION("HID Sensor common attribute processing");
 436 MODULE_LICENSE("GPL");