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/types.h> 19 #include <linux/module.h> 20 #include <linux/regmap.h> 21 #include <linux/bitops.h> 22 #include <linux/delay.h> 23 #include <linux/regulator/consumer.h> 24 #include <linux/pm_runtime.h> 25 #include <linux/iio/iio.h> 26 #include <linux/iio/sysfs.h> 27 #include <linux/iio/buffer.h> 28 #include <linux/iio/triggered_buffer.h> 29 #include <linux/iio/trigger_consumer.h> 30 31 #include "kxsd9.h" 32 33 #define KXSD9_REG_X 0x00 34 #define KXSD9_REG_Y 0x02 35 #define KXSD9_REG_Z 0x04 36 #define KXSD9_REG_AUX 0x06 37 #define KXSD9_REG_RESET 0x0a 38 #define KXSD9_REG_CTRL_C 0x0c 39 40 #define KXSD9_CTRL_C_FS_MASK 0x03 41 #define KXSD9_CTRL_C_FS_8G 0x00 42 #define KXSD9_CTRL_C_FS_6G 0x01 43 #define KXSD9_CTRL_C_FS_4G 0x02 44 #define KXSD9_CTRL_C_FS_2G 0x03 45 #define KXSD9_CTRL_C_MOT_LAT BIT(3) 46 #define KXSD9_CTRL_C_MOT_LEV BIT(4) 47 #define KXSD9_CTRL_C_LP_MASK 0xe0 48 #define KXSD9_CTRL_C_LP_NONE 0x00 49 #define KXSD9_CTRL_C_LP_2000HZC BIT(5) 50 #define KXSD9_CTRL_C_LP_2000HZB BIT(6) 51 #define KXSD9_CTRL_C_LP_2000HZA (BIT(5)|BIT(6)) 52 #define KXSD9_CTRL_C_LP_1000HZ BIT(7) 53 #define KXSD9_CTRL_C_LP_500HZ (BIT(7)|BIT(5)) 54 #define KXSD9_CTRL_C_LP_100HZ (BIT(7)|BIT(6)) 55 #define KXSD9_CTRL_C_LP_50HZ (BIT(7)|BIT(6)|BIT(5)) 56 57 #define KXSD9_REG_CTRL_B 0x0d 58 59 #define KXSD9_CTRL_B_CLK_HLD BIT(7) 60 #define KXSD9_CTRL_B_ENABLE BIT(6) 61 #define KXSD9_CTRL_B_ST BIT(5) /* Self-test */ 62 63 #define KXSD9_REG_CTRL_A 0x0e 64 65 /** 66 * struct kxsd9_state - device related storage 67 * @dev: pointer to the parent device 68 * @map: regmap to the device 69 * @orientation: mounting matrix, flipped axis etc 70 * @regs: regulators for this device, VDD and IOVDD 71 * @scale: the current scaling setting 72 */ 73 struct kxsd9_state { 74 struct device *dev; 75 struct regmap *map; 76 struct iio_mount_matrix orientation; 77 struct regulator_bulk_data regs[2]; 78 u8 scale; 79 }; 80 81 #define KXSD9_SCALE_2G "0.011978" 82 #define KXSD9_SCALE_4G "0.023927" 83 #define KXSD9_SCALE_6G "0.035934" 84 #define KXSD9_SCALE_8G "0.047853" 85 86 /* reverse order */ 87 static const int kxsd9_micro_scales[4] = { 47853, 35934, 23927, 11978 }; 88 89 #define KXSD9_ZERO_G_OFFSET -2048 90 91 /* 92 * Regulator names 93 */ 94 static const char kxsd9_reg_vdd[] = "vdd"; 95 static const char kxsd9_reg_iovdd[] = "iovdd"; 96 97 static int kxsd9_write_scale(struct iio_dev *indio_dev, int micro) 98 { 99 int ret, i; 100 struct kxsd9_state *st = iio_priv(indio_dev); 101 bool foundit = false; 102 103 for (i = 0; i < 4; i++) 104 if (micro == kxsd9_micro_scales[i]) { 105 foundit = true; 106 break; 107 } 108 if (!foundit) 109 return -EINVAL; 110 111 ret = regmap_update_bits(st->map, 112 KXSD9_REG_CTRL_C, 113 KXSD9_CTRL_C_FS_MASK, 114 i); 115 if (ret < 0) 116 goto error_ret; 117 118 /* Cached scale when the sensor is powered down */ 119 st->scale = i; 120 121 error_ret: 122 return ret; 123 } 124 125 static IIO_CONST_ATTR(accel_scale_available, 126 KXSD9_SCALE_2G " " 127 KXSD9_SCALE_4G " " 128 KXSD9_SCALE_6G " " 129 KXSD9_SCALE_8G); 130 131 static struct attribute *kxsd9_attributes[] = { 132 &iio_const_attr_accel_scale_available.dev_attr.attr, 133 NULL, 134 }; 135 136 static int kxsd9_write_raw(struct iio_dev *indio_dev, 137 struct iio_chan_spec const *chan, 138 int val, 139 int val2, 140 long mask) 141 { 142 int ret = -EINVAL; 143 struct kxsd9_state *st = iio_priv(indio_dev); 144 145 pm_runtime_get_sync(st->dev); 146 147 if (mask == IIO_CHAN_INFO_SCALE) { 148 /* Check no integer component */ 149 if (val) 150 return -EINVAL; 151 ret = kxsd9_write_scale(indio_dev, val2); 152 } 153 154 pm_runtime_mark_last_busy(st->dev); 155 pm_runtime_put_autosuspend(st->dev); 156 157 return ret; 158 } 159 160 static int kxsd9_read_raw(struct iio_dev *indio_dev, 161 struct iio_chan_spec const *chan, 162 int *val, int *val2, long mask) 163 { 164 int ret = -EINVAL; 165 struct kxsd9_state *st = iio_priv(indio_dev); 166 unsigned int regval; 167 __be16 raw_val; 168 u16 nval; 169 170 pm_runtime_get_sync(st->dev); 171 172 switch (mask) { 173 case IIO_CHAN_INFO_RAW: 174 ret = regmap_bulk_read(st->map, chan->address, &raw_val, 175 sizeof(raw_val)); 176 if (ret) 177 goto error_ret; 178 nval = be16_to_cpu(raw_val); 179 /* Only 12 bits are valid */ 180 nval >>= 4; 181 *val = nval; 182 ret = IIO_VAL_INT; 183 break; 184 case IIO_CHAN_INFO_OFFSET: 185 /* This has a bias of -2048 */ 186 *val = KXSD9_ZERO_G_OFFSET; 187 ret = IIO_VAL_INT; 188 break; 189 case IIO_CHAN_INFO_SCALE: 190 ret = regmap_read(st->map, 191 KXSD9_REG_CTRL_C, 192 ®val); 193 if (ret < 0) 194 goto error_ret; 195 *val = 0; 196 *val2 = kxsd9_micro_scales[regval & KXSD9_CTRL_C_FS_MASK]; 197 ret = IIO_VAL_INT_PLUS_MICRO; 198 break; 199 } 200 201 error_ret: 202 pm_runtime_mark_last_busy(st->dev); 203 pm_runtime_put_autosuspend(st->dev); 204 205 return ret; 206 }; 207 208 static irqreturn_t kxsd9_trigger_handler(int irq, void *p) 209 { 210 const struct iio_poll_func *pf = p; 211 struct iio_dev *indio_dev = pf->indio_dev; 212 struct kxsd9_state *st = iio_priv(indio_dev); 213 /* 214 * Ensure correct positioning and alignment of timestamp. 215 * No need to zero initialize as all elements written. 216 */ 217 struct { 218 __be16 chan[4]; 219 aligned_s64 ts; 220 } hw_values; 221 int ret; 222 223 ret = regmap_bulk_read(st->map, 224 KXSD9_REG_X, 225 hw_values.chan, 226 sizeof(hw_values.chan)); 227 if (ret) { 228 dev_err(st->dev, "error reading data: %d\n", ret); 229 goto out; 230 } 231 232 iio_push_to_buffers_with_ts(indio_dev, &hw_values, sizeof(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_clear_bits(st->map, KXSD9_REG_CTRL_B, KXSD9_CTRL_B_ENABLE); 374 if (ret) 375 return ret; 376 377 /* Disable the regulators */ 378 ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs); 379 if (ret) { 380 dev_err(st->dev, "Cannot disable regulators\n"); 381 return ret; 382 } 383 384 return 0; 385 } 386 387 static const struct iio_info kxsd9_info = { 388 .read_raw = &kxsd9_read_raw, 389 .write_raw = &kxsd9_write_raw, 390 .attrs = &kxsd9_attribute_group, 391 }; 392 393 /* Four channels apart from timestamp, scan mask = 0x0f */ 394 static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 }; 395 396 int kxsd9_common_probe(struct device *dev, 397 struct regmap *map, 398 const char *name) 399 { 400 struct iio_dev *indio_dev; 401 struct kxsd9_state *st; 402 int ret; 403 404 indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); 405 if (!indio_dev) 406 return -ENOMEM; 407 408 st = iio_priv(indio_dev); 409 st->dev = dev; 410 st->map = map; 411 412 indio_dev->channels = kxsd9_channels; 413 indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels); 414 indio_dev->name = name; 415 indio_dev->info = &kxsd9_info; 416 indio_dev->modes = INDIO_DIRECT_MODE; 417 indio_dev->available_scan_masks = kxsd9_scan_masks; 418 419 /* Read the mounting matrix, if present */ 420 ret = iio_read_mount_matrix(dev, &st->orientation); 421 if (ret) 422 return ret; 423 424 /* Fetch and turn on regulators */ 425 st->regs[0].supply = kxsd9_reg_vdd; 426 st->regs[1].supply = kxsd9_reg_iovdd; 427 ret = devm_regulator_bulk_get(dev, 428 ARRAY_SIZE(st->regs), 429 st->regs); 430 if (ret) { 431 dev_err(dev, "Cannot get regulators\n"); 432 return ret; 433 } 434 /* Default scaling */ 435 st->scale = KXSD9_CTRL_C_FS_2G; 436 437 kxsd9_power_up(st); 438 439 ret = iio_triggered_buffer_setup(indio_dev, 440 iio_pollfunc_store_time, 441 kxsd9_trigger_handler, 442 &kxsd9_buffer_setup_ops); 443 if (ret) { 444 dev_err(dev, "triggered buffer setup failed\n"); 445 goto err_power_down; 446 } 447 448 ret = iio_device_register(indio_dev); 449 if (ret) 450 goto err_cleanup_buffer; 451 452 dev_set_drvdata(dev, indio_dev); 453 454 /* Enable runtime PM */ 455 pm_runtime_get_noresume(dev); 456 pm_runtime_set_active(dev); 457 pm_runtime_enable(dev); 458 /* 459 * Set autosuspend to two orders of magnitude larger than the 460 * start-up time. 20ms start-up time means 2000ms autosuspend, 461 * i.e. 2 seconds. 462 */ 463 pm_runtime_set_autosuspend_delay(dev, 2000); 464 pm_runtime_use_autosuspend(dev); 465 pm_runtime_put(dev); 466 467 return 0; 468 469 err_cleanup_buffer: 470 iio_triggered_buffer_cleanup(indio_dev); 471 err_power_down: 472 kxsd9_power_down(st); 473 474 return ret; 475 } 476 EXPORT_SYMBOL_NS(kxsd9_common_probe, "IIO_KXSD9"); 477 478 void kxsd9_common_remove(struct device *dev) 479 { 480 struct iio_dev *indio_dev = dev_get_drvdata(dev); 481 struct kxsd9_state *st = iio_priv(indio_dev); 482 483 iio_triggered_buffer_cleanup(indio_dev); 484 iio_device_unregister(indio_dev); 485 pm_runtime_get_sync(dev); 486 pm_runtime_put_noidle(dev); 487 pm_runtime_disable(dev); 488 kxsd9_power_down(st); 489 } 490 EXPORT_SYMBOL_NS(kxsd9_common_remove, "IIO_KXSD9"); 491 492 static int kxsd9_runtime_suspend(struct device *dev) 493 { 494 struct iio_dev *indio_dev = dev_get_drvdata(dev); 495 struct kxsd9_state *st = iio_priv(indio_dev); 496 497 return kxsd9_power_down(st); 498 } 499 500 static int kxsd9_runtime_resume(struct device *dev) 501 { 502 struct iio_dev *indio_dev = dev_get_drvdata(dev); 503 struct kxsd9_state *st = iio_priv(indio_dev); 504 505 return kxsd9_power_up(st); 506 } 507 508 EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend, 509 kxsd9_runtime_resume, NULL, IIO_KXSD9); 510 511 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>"); 512 MODULE_DESCRIPTION("Kionix KXSD9 driver"); 513 MODULE_LICENSE("GPL v2"); 514