1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * kxsd9.c simple support for the Kionix KXSD9 3D 4 * accelerometer. 5 * 6 * Copyright (c) 2008-2009 Jonathan Cameron <jic23@kernel.org> 7 * 8 * The i2c interface is very similar, so shouldn't be a problem once 9 * I have a suitable wire made up. 10 * 11 * TODO: Support the motion detector 12 */ 13 14 #include <linux/device.h> 15 #include <linux/kernel.h> 16 #include <linux/sysfs.h> 17 #include <linux/slab.h> 18 #include <linux/module.h> 19 #include <linux/regmap.h> 20 #include <linux/bitops.h> 21 #include <linux/delay.h> 22 #include <linux/regulator/consumer.h> 23 #include <linux/pm_runtime.h> 24 #include <linux/iio/iio.h> 25 #include <linux/iio/sysfs.h> 26 #include <linux/iio/buffer.h> 27 #include <linux/iio/triggered_buffer.h> 28 #include <linux/iio/trigger_consumer.h> 29 30 #include "kxsd9.h" 31 32 #define KXSD9_REG_X 0x00 33 #define KXSD9_REG_Y 0x02 34 #define KXSD9_REG_Z 0x04 35 #define KXSD9_REG_AUX 0x06 36 #define KXSD9_REG_RESET 0x0a 37 #define KXSD9_REG_CTRL_C 0x0c 38 39 #define KXSD9_CTRL_C_FS_MASK 0x03 40 #define KXSD9_CTRL_C_FS_8G 0x00 41 #define KXSD9_CTRL_C_FS_6G 0x01 42 #define KXSD9_CTRL_C_FS_4G 0x02 43 #define KXSD9_CTRL_C_FS_2G 0x03 44 #define KXSD9_CTRL_C_MOT_LAT BIT(3) 45 #define KXSD9_CTRL_C_MOT_LEV BIT(4) 46 #define KXSD9_CTRL_C_LP_MASK 0xe0 47 #define KXSD9_CTRL_C_LP_NONE 0x00 48 #define KXSD9_CTRL_C_LP_2000HZC BIT(5) 49 #define KXSD9_CTRL_C_LP_2000HZB BIT(6) 50 #define KXSD9_CTRL_C_LP_2000HZA (BIT(5)|BIT(6)) 51 #define KXSD9_CTRL_C_LP_1000HZ BIT(7) 52 #define KXSD9_CTRL_C_LP_500HZ (BIT(7)|BIT(5)) 53 #define KXSD9_CTRL_C_LP_100HZ (BIT(7)|BIT(6)) 54 #define KXSD9_CTRL_C_LP_50HZ (BIT(7)|BIT(6)|BIT(5)) 55 56 #define KXSD9_REG_CTRL_B 0x0d 57 58 #define KXSD9_CTRL_B_CLK_HLD BIT(7) 59 #define KXSD9_CTRL_B_ENABLE BIT(6) 60 #define KXSD9_CTRL_B_ST BIT(5) /* Self-test */ 61 62 #define KXSD9_REG_CTRL_A 0x0e 63 64 /** 65 * struct kxsd9_state - device related storage 66 * @dev: pointer to the parent device 67 * @map: regmap to the device 68 * @orientation: mounting matrix, flipped axis etc 69 * @regs: regulators for this device, VDD and IOVDD 70 * @scale: the current scaling setting 71 */ 72 struct kxsd9_state { 73 struct device *dev; 74 struct regmap *map; 75 struct iio_mount_matrix orientation; 76 struct regulator_bulk_data regs[2]; 77 u8 scale; 78 }; 79 80 #define KXSD9_SCALE_2G "0.011978" 81 #define KXSD9_SCALE_4G "0.023927" 82 #define KXSD9_SCALE_6G "0.035934" 83 #define KXSD9_SCALE_8G "0.047853" 84 85 /* reverse order */ 86 static const int kxsd9_micro_scales[4] = { 47853, 35934, 23927, 11978 }; 87 88 #define KXSD9_ZERO_G_OFFSET -2048 89 90 /* 91 * Regulator names 92 */ 93 static const char kxsd9_reg_vdd[] = "vdd"; 94 static const char kxsd9_reg_iovdd[] = "iovdd"; 95 96 static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro) 97 { 98 int ret, i; 99 struct kxsd9_state *st = iio_priv(indio_dev); 100 bool foundit = false; 101 102 for (i = 0; i < 4; i++) 103 if (micro == kxsd9_micro_scales[i]) { 104 foundit = true; 105 break; 106 } 107 if (!foundit) 108 return -EINVAL; 109 110 ret = regmap_update_bits(st->map, 111 KXSD9_REG_CTRL_C, 112 KXSD9_CTRL_C_FS_MASK, 113 i); 114 if (ret < 0) 115 goto error_ret; 116 117 /* Cached scale when the sensor is powered down */ 118 st->scale = i; 119 120 error_ret: 121 return ret; 122 } 123 124 static IIO_CONST_ATTR(accel_scale_available, 125 KXSD9_SCALE_2G " " 126 KXSD9_SCALE_4G " " 127 KXSD9_SCALE_6G " " 128 KXSD9_SCALE_8G); 129 130 static struct attribute *kxsd9_attributes[] = { 131 &iio_const_attr_accel_scale_available.dev_attr.attr, 132 NULL, 133 }; 134 135 static int kxsd9_write_raw(struct iio_dev *indio_dev, 136 struct iio_chan_spec const *chan, 137 int val, 138 int val2, 139 long mask) 140 { 141 int ret = -EINVAL; 142 struct kxsd9_state *st = iio_priv(indio_dev); 143 144 pm_runtime_get_sync(st->dev); 145 146 if (mask == IIO_CHAN_INFO_SCALE) { 147 /* Check no integer component */ 148 if (val) 149 return -EINVAL; 150 ret = kxsd9_write_scale(indio_dev, val2); 151 } 152 153 pm_runtime_mark_last_busy(st->dev); 154 pm_runtime_put_autosuspend(st->dev); 155 156 return ret; 157 } 158 159 static int kxsd9_read_raw(struct iio_dev *indio_dev, 160 struct iio_chan_spec const *chan, 161 int *val, int *val2, long mask) 162 { 163 int ret = -EINVAL; 164 struct kxsd9_state *st = iio_priv(indio_dev); 165 unsigned int regval; 166 __be16 raw_val; 167 u16 nval; 168 169 pm_runtime_get_sync(st->dev); 170 171 switch (mask) { 172 case IIO_CHAN_INFO_RAW: 173 ret = regmap_bulk_read(st->map, chan->address, &raw_val, 174 sizeof(raw_val)); 175 if (ret) 176 goto error_ret; 177 nval = be16_to_cpu(raw_val); 178 /* Only 12 bits are valid */ 179 nval >>= 4; 180 *val = nval; 181 ret = IIO_VAL_INT; 182 break; 183 case IIO_CHAN_INFO_OFFSET: 184 /* This has a bias of -2048 */ 185 *val = KXSD9_ZERO_G_OFFSET; 186 ret = IIO_VAL_INT; 187 break; 188 case IIO_CHAN_INFO_SCALE: 189 ret = regmap_read(st->map, 190 KXSD9_REG_CTRL_C, 191 ®val); 192 if (ret < 0) 193 goto error_ret; 194 *val = 0; 195 *val2 = kxsd9_micro_scales[regval & KXSD9_CTRL_C_FS_MASK]; 196 ret = IIO_VAL_INT_PLUS_MICRO; 197 break; 198 } 199 200 error_ret: 201 pm_runtime_mark_last_busy(st->dev); 202 pm_runtime_put_autosuspend(st->dev); 203 204 return ret; 205 }; 206 207 static irqreturn_t kxsd9_trigger_handler(int irq, void *p) 208 { 209 const struct iio_poll_func *pf = p; 210 struct iio_dev *indio_dev = pf->indio_dev; 211 struct kxsd9_state *st = iio_priv(indio_dev); 212 /* 213 * Ensure correct positioning and alignment of timestamp. 214 * No need to zero initialize as all elements written. 215 */ 216 struct { 217 __be16 chan[4]; 218 s64 ts __aligned(8); 219 } hw_values; 220 int ret; 221 222 ret = regmap_bulk_read(st->map, 223 KXSD9_REG_X, 224 hw_values.chan, 225 sizeof(hw_values.chan)); 226 if (ret) { 227 dev_err(st->dev, "error reading data: %d\n", ret); 228 goto out; 229 } 230 231 iio_push_to_buffers_with_timestamp(indio_dev, 232 &hw_values, 233 iio_get_time_ns(indio_dev)); 234 out: 235 iio_trigger_notify_done(indio_dev->trig); 236 237 return IRQ_HANDLED; 238 } 239 240 static int kxsd9_buffer_preenable(struct iio_dev *indio_dev) 241 { 242 struct kxsd9_state *st = iio_priv(indio_dev); 243 244 pm_runtime_get_sync(st->dev); 245 246 return 0; 247 } 248 249 static int kxsd9_buffer_postdisable(struct iio_dev *indio_dev) 250 { 251 struct kxsd9_state *st = iio_priv(indio_dev); 252 253 pm_runtime_mark_last_busy(st->dev); 254 pm_runtime_put_autosuspend(st->dev); 255 256 return 0; 257 } 258 259 static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = { 260 .preenable = kxsd9_buffer_preenable, 261 .postdisable = kxsd9_buffer_postdisable, 262 }; 263 264 static const struct iio_mount_matrix * 265 kxsd9_get_mount_matrix(const struct iio_dev *indio_dev, 266 const struct iio_chan_spec *chan) 267 { 268 struct kxsd9_state *st = iio_priv(indio_dev); 269 270 return &st->orientation; 271 } 272 273 static const struct iio_chan_spec_ext_info kxsd9_ext_info[] = { 274 IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kxsd9_get_mount_matrix), 275 { }, 276 }; 277 278 #define KXSD9_ACCEL_CHAN(axis, index) \ 279 { \ 280 .type = IIO_ACCEL, \ 281 .modified = 1, \ 282 .channel2 = IIO_MOD_##axis, \ 283 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 284 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ 285 BIT(IIO_CHAN_INFO_OFFSET), \ 286 .ext_info = kxsd9_ext_info, \ 287 .address = KXSD9_REG_##axis, \ 288 .scan_index = index, \ 289 .scan_type = { \ 290 .sign = 'u', \ 291 .realbits = 12, \ 292 .storagebits = 16, \ 293 .shift = 4, \ 294 .endianness = IIO_BE, \ 295 }, \ 296 } 297 298 static const struct iio_chan_spec kxsd9_channels[] = { 299 KXSD9_ACCEL_CHAN(X, 0), 300 KXSD9_ACCEL_CHAN(Y, 1), 301 KXSD9_ACCEL_CHAN(Z, 2), 302 { 303 .type = IIO_VOLTAGE, 304 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 305 .indexed = 1, 306 .address = KXSD9_REG_AUX, 307 .scan_index = 3, 308 .scan_type = { 309 .sign = 'u', 310 .realbits = 12, 311 .storagebits = 16, 312 .shift = 4, 313 .endianness = IIO_BE, 314 }, 315 }, 316 IIO_CHAN_SOFT_TIMESTAMP(4), 317 }; 318 319 static const struct attribute_group kxsd9_attribute_group = { 320 .attrs = kxsd9_attributes, 321 }; 322 323 static int kxsd9_power_up(struct kxsd9_state *st) 324 { 325 int ret; 326 327 /* Enable the regulators */ 328 ret = regulator_bulk_enable(ARRAY_SIZE(st->regs), st->regs); 329 if (ret) { 330 dev_err(st->dev, "Cannot enable regulators\n"); 331 return ret; 332 } 333 334 /* Power up */ 335 ret = regmap_write(st->map, 336 KXSD9_REG_CTRL_B, 337 KXSD9_CTRL_B_ENABLE); 338 if (ret) 339 return ret; 340 341 /* 342 * Set 1000Hz LPF, 2g fullscale, motion wakeup threshold 1g, 343 * latched wakeup 344 */ 345 ret = regmap_write(st->map, 346 KXSD9_REG_CTRL_C, 347 KXSD9_CTRL_C_LP_1000HZ | 348 KXSD9_CTRL_C_MOT_LEV | 349 KXSD9_CTRL_C_MOT_LAT | 350 st->scale); 351 if (ret) 352 return ret; 353 354 /* 355 * Power-up time depends on the LPF setting, but typ 15.9 ms, let's 356 * set 20 ms to allow for some slack. 357 */ 358 msleep(20); 359 360 return 0; 361 }; 362 363 static int kxsd9_power_down(struct kxsd9_state *st) 364 { 365 int ret; 366 367 /* 368 * Set into low power mode - since there may be more users of the 369 * regulators this is the first step of the power saving: it will 370 * make sure we conserve power even if there are others users on the 371 * regulators. 372 */ 373 ret = regmap_update_bits(st->map, 374 KXSD9_REG_CTRL_B, 375 KXSD9_CTRL_B_ENABLE, 376 0); 377 if (ret) 378 return ret; 379 380 /* Disable the regulators */ 381 ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs); 382 if (ret) { 383 dev_err(st->dev, "Cannot disable regulators\n"); 384 return ret; 385 } 386 387 return 0; 388 } 389 390 static const struct iio_info kxsd9_info = { 391 .read_raw = &kxsd9_read_raw, 392 .write_raw = &kxsd9_write_raw, 393 .attrs = &kxsd9_attribute_group, 394 }; 395 396 /* Four channels apart from timestamp, scan mask = 0x0f */ 397 static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 }; 398 399 int kxsd9_common_probe(struct device *dev, 400 struct regmap *map, 401 const char *name) 402 { 403 struct iio_dev *indio_dev; 404 struct kxsd9_state *st; 405 int ret; 406 407 indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); 408 if (!indio_dev) 409 return -ENOMEM; 410 411 st = iio_priv(indio_dev); 412 st->dev = dev; 413 st->map = map; 414 415 indio_dev->channels = kxsd9_channels; 416 indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels); 417 indio_dev->name = name; 418 indio_dev->info = &kxsd9_info; 419 indio_dev->modes = INDIO_DIRECT_MODE; 420 indio_dev->available_scan_masks = kxsd9_scan_masks; 421 422 /* Read the mounting matrix, if present */ 423 ret = iio_read_mount_matrix(dev, &st->orientation); 424 if (ret) 425 return ret; 426 427 /* Fetch and turn on regulators */ 428 st->regs[0].supply = kxsd9_reg_vdd; 429 st->regs[1].supply = kxsd9_reg_iovdd; 430 ret = devm_regulator_bulk_get(dev, 431 ARRAY_SIZE(st->regs), 432 st->regs); 433 if (ret) { 434 dev_err(dev, "Cannot get regulators\n"); 435 return ret; 436 } 437 /* Default scaling */ 438 st->scale = KXSD9_CTRL_C_FS_2G; 439 440 kxsd9_power_up(st); 441 442 ret = iio_triggered_buffer_setup(indio_dev, 443 iio_pollfunc_store_time, 444 kxsd9_trigger_handler, 445 &kxsd9_buffer_setup_ops); 446 if (ret) { 447 dev_err(dev, "triggered buffer setup failed\n"); 448 goto err_power_down; 449 } 450 451 ret = iio_device_register(indio_dev); 452 if (ret) 453 goto err_cleanup_buffer; 454 455 dev_set_drvdata(dev, indio_dev); 456 457 /* Enable runtime PM */ 458 pm_runtime_get_noresume(dev); 459 pm_runtime_set_active(dev); 460 pm_runtime_enable(dev); 461 /* 462 * Set autosuspend to two orders of magnitude larger than the 463 * start-up time. 20ms start-up time means 2000ms autosuspend, 464 * i.e. 2 seconds. 465 */ 466 pm_runtime_set_autosuspend_delay(dev, 2000); 467 pm_runtime_use_autosuspend(dev); 468 pm_runtime_put(dev); 469 470 return 0; 471 472 err_cleanup_buffer: 473 iio_triggered_buffer_cleanup(indio_dev); 474 err_power_down: 475 kxsd9_power_down(st); 476 477 return ret; 478 } 479 EXPORT_SYMBOL_NS(kxsd9_common_probe, IIO_KXSD9); 480 481 void kxsd9_common_remove(struct device *dev) 482 { 483 struct iio_dev *indio_dev = dev_get_drvdata(dev); 484 struct kxsd9_state *st = iio_priv(indio_dev); 485 486 iio_triggered_buffer_cleanup(indio_dev); 487 iio_device_unregister(indio_dev); 488 pm_runtime_get_sync(dev); 489 pm_runtime_put_noidle(dev); 490 pm_runtime_disable(dev); 491 kxsd9_power_down(st); 492 } 493 EXPORT_SYMBOL_NS(kxsd9_common_remove, IIO_KXSD9); 494 495 static int kxsd9_runtime_suspend(struct device *dev) 496 { 497 struct iio_dev *indio_dev = dev_get_drvdata(dev); 498 struct kxsd9_state *st = iio_priv(indio_dev); 499 500 return kxsd9_power_down(st); 501 } 502 503 static int kxsd9_runtime_resume(struct device *dev) 504 { 505 struct iio_dev *indio_dev = dev_get_drvdata(dev); 506 struct kxsd9_state *st = iio_priv(indio_dev); 507 508 return kxsd9_power_up(st); 509 } 510 511 EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend, 512 kxsd9_runtime_resume, NULL, IIO_KXSD9); 513 514 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>"); 515 MODULE_DESCRIPTION("Kionix KXSD9 driver"); 516 MODULE_LICENSE("GPL v2"); 517