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_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_put_autosuspend(st->dev); 202 203 return ret; 204 }; 205 206 static irqreturn_t kxsd9_trigger_handler(int irq, void *p) 207 { 208 const struct iio_poll_func *pf = p; 209 struct iio_dev *indio_dev = pf->indio_dev; 210 struct kxsd9_state *st = iio_priv(indio_dev); 211 /* 212 * Ensure correct positioning and alignment of timestamp. 213 * No need to zero initialize as all elements written. 214 */ 215 struct { 216 __be16 chan[4]; 217 aligned_s64 ts; 218 } hw_values; 219 int ret; 220 221 ret = regmap_bulk_read(st->map, 222 KXSD9_REG_X, 223 hw_values.chan, 224 sizeof(hw_values.chan)); 225 if (ret) { 226 dev_err(st->dev, "error reading data: %d\n", ret); 227 goto out; 228 } 229 230 iio_push_to_buffers_with_ts(indio_dev, &hw_values, sizeof(hw_values), 231 iio_get_time_ns(indio_dev)); 232 out: 233 iio_trigger_notify_done(indio_dev->trig); 234 235 return IRQ_HANDLED; 236 } 237 238 static int kxsd9_buffer_preenable(struct iio_dev *indio_dev) 239 { 240 struct kxsd9_state *st = iio_priv(indio_dev); 241 242 pm_runtime_get_sync(st->dev); 243 244 return 0; 245 } 246 247 static int kxsd9_buffer_postdisable(struct iio_dev *indio_dev) 248 { 249 struct kxsd9_state *st = iio_priv(indio_dev); 250 251 pm_runtime_put_autosuspend(st->dev); 252 253 return 0; 254 } 255 256 static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = { 257 .preenable = kxsd9_buffer_preenable, 258 .postdisable = kxsd9_buffer_postdisable, 259 }; 260 261 static const struct iio_mount_matrix * 262 kxsd9_get_mount_matrix(const struct iio_dev *indio_dev, 263 const struct iio_chan_spec *chan) 264 { 265 struct kxsd9_state *st = iio_priv(indio_dev); 266 267 return &st->orientation; 268 } 269 270 static const struct iio_chan_spec_ext_info kxsd9_ext_info[] = { 271 IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kxsd9_get_mount_matrix), 272 { } 273 }; 274 275 #define KXSD9_ACCEL_CHAN(axis, index) \ 276 { \ 277 .type = IIO_ACCEL, \ 278 .modified = 1, \ 279 .channel2 = IIO_MOD_##axis, \ 280 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 281 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ 282 BIT(IIO_CHAN_INFO_OFFSET), \ 283 .ext_info = kxsd9_ext_info, \ 284 .address = KXSD9_REG_##axis, \ 285 .scan_index = index, \ 286 .scan_type = { \ 287 .sign = 'u', \ 288 .realbits = 12, \ 289 .storagebits = 16, \ 290 .shift = 4, \ 291 .endianness = IIO_BE, \ 292 }, \ 293 } 294 295 static const struct iio_chan_spec kxsd9_channels[] = { 296 KXSD9_ACCEL_CHAN(X, 0), 297 KXSD9_ACCEL_CHAN(Y, 1), 298 KXSD9_ACCEL_CHAN(Z, 2), 299 { 300 .type = IIO_VOLTAGE, 301 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 302 .indexed = 1, 303 .address = KXSD9_REG_AUX, 304 .scan_index = 3, 305 .scan_type = { 306 .sign = 'u', 307 .realbits = 12, 308 .storagebits = 16, 309 .shift = 4, 310 .endianness = IIO_BE, 311 }, 312 }, 313 IIO_CHAN_SOFT_TIMESTAMP(4), 314 }; 315 316 static const struct attribute_group kxsd9_attribute_group = { 317 .attrs = kxsd9_attributes, 318 }; 319 320 static int kxsd9_power_up(struct kxsd9_state *st) 321 { 322 int ret; 323 324 /* Enable the regulators */ 325 ret = regulator_bulk_enable(ARRAY_SIZE(st->regs), st->regs); 326 if (ret) { 327 dev_err(st->dev, "Cannot enable regulators\n"); 328 return ret; 329 } 330 331 /* Power up */ 332 ret = regmap_write(st->map, 333 KXSD9_REG_CTRL_B, 334 KXSD9_CTRL_B_ENABLE); 335 if (ret) 336 return ret; 337 338 /* 339 * Set 1000Hz LPF, 2g fullscale, motion wakeup threshold 1g, 340 * latched wakeup 341 */ 342 ret = regmap_write(st->map, 343 KXSD9_REG_CTRL_C, 344 KXSD9_CTRL_C_LP_1000HZ | 345 KXSD9_CTRL_C_MOT_LEV | 346 KXSD9_CTRL_C_MOT_LAT | 347 st->scale); 348 if (ret) 349 return ret; 350 351 /* 352 * Power-up time depends on the LPF setting, but typ 15.9 ms, let's 353 * set 20 ms to allow for some slack. 354 */ 355 msleep(20); 356 357 return 0; 358 }; 359 360 static int kxsd9_power_down(struct kxsd9_state *st) 361 { 362 int ret; 363 364 /* 365 * Set into low power mode - since there may be more users of the 366 * regulators this is the first step of the power saving: it will 367 * make sure we conserve power even if there are others users on the 368 * regulators. 369 */ 370 ret = regmap_clear_bits(st->map, KXSD9_REG_CTRL_B, KXSD9_CTRL_B_ENABLE); 371 if (ret) 372 return ret; 373 374 /* Disable the regulators */ 375 ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs); 376 if (ret) { 377 dev_err(st->dev, "Cannot disable regulators\n"); 378 return ret; 379 } 380 381 return 0; 382 } 383 384 static const struct iio_info kxsd9_info = { 385 .read_raw = &kxsd9_read_raw, 386 .write_raw = &kxsd9_write_raw, 387 .attrs = &kxsd9_attribute_group, 388 }; 389 390 /* Four channels apart from timestamp, scan mask = 0x0f */ 391 static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 }; 392 393 int kxsd9_common_probe(struct device *dev, 394 struct regmap *map, 395 const char *name) 396 { 397 struct iio_dev *indio_dev; 398 struct kxsd9_state *st; 399 int ret; 400 401 indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); 402 if (!indio_dev) 403 return -ENOMEM; 404 405 st = iio_priv(indio_dev); 406 st->dev = dev; 407 st->map = map; 408 409 indio_dev->channels = kxsd9_channels; 410 indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels); 411 indio_dev->name = name; 412 indio_dev->info = &kxsd9_info; 413 indio_dev->modes = INDIO_DIRECT_MODE; 414 indio_dev->available_scan_masks = kxsd9_scan_masks; 415 416 /* Read the mounting matrix, if present */ 417 ret = iio_read_mount_matrix(dev, &st->orientation); 418 if (ret) 419 return ret; 420 421 /* Fetch and turn on regulators */ 422 st->regs[0].supply = kxsd9_reg_vdd; 423 st->regs[1].supply = kxsd9_reg_iovdd; 424 ret = devm_regulator_bulk_get(dev, 425 ARRAY_SIZE(st->regs), 426 st->regs); 427 if (ret) { 428 dev_err(dev, "Cannot get regulators\n"); 429 return ret; 430 } 431 /* Default scaling */ 432 st->scale = KXSD9_CTRL_C_FS_2G; 433 434 kxsd9_power_up(st); 435 436 ret = iio_triggered_buffer_setup(indio_dev, 437 iio_pollfunc_store_time, 438 kxsd9_trigger_handler, 439 &kxsd9_buffer_setup_ops); 440 if (ret) { 441 dev_err(dev, "triggered buffer setup failed\n"); 442 goto err_power_down; 443 } 444 445 ret = iio_device_register(indio_dev); 446 if (ret) 447 goto err_cleanup_buffer; 448 449 dev_set_drvdata(dev, indio_dev); 450 451 /* Enable runtime PM */ 452 pm_runtime_get_noresume(dev); 453 pm_runtime_set_active(dev); 454 pm_runtime_enable(dev); 455 /* 456 * Set autosuspend to two orders of magnitude larger than the 457 * start-up time. 20ms start-up time means 2000ms autosuspend, 458 * i.e. 2 seconds. 459 */ 460 pm_runtime_set_autosuspend_delay(dev, 2000); 461 pm_runtime_use_autosuspend(dev); 462 pm_runtime_put(dev); 463 464 return 0; 465 466 err_cleanup_buffer: 467 iio_triggered_buffer_cleanup(indio_dev); 468 err_power_down: 469 kxsd9_power_down(st); 470 471 return ret; 472 } 473 EXPORT_SYMBOL_NS(kxsd9_common_probe, "IIO_KXSD9"); 474 475 void kxsd9_common_remove(struct device *dev) 476 { 477 struct iio_dev *indio_dev = dev_get_drvdata(dev); 478 struct kxsd9_state *st = iio_priv(indio_dev); 479 480 iio_triggered_buffer_cleanup(indio_dev); 481 iio_device_unregister(indio_dev); 482 pm_runtime_get_sync(dev); 483 pm_runtime_put_noidle(dev); 484 pm_runtime_disable(dev); 485 kxsd9_power_down(st); 486 } 487 EXPORT_SYMBOL_NS(kxsd9_common_remove, "IIO_KXSD9"); 488 489 static int kxsd9_runtime_suspend(struct device *dev) 490 { 491 struct iio_dev *indio_dev = dev_get_drvdata(dev); 492 struct kxsd9_state *st = iio_priv(indio_dev); 493 494 return kxsd9_power_down(st); 495 } 496 497 static int kxsd9_runtime_resume(struct device *dev) 498 { 499 struct iio_dev *indio_dev = dev_get_drvdata(dev); 500 struct kxsd9_state *st = iio_priv(indio_dev); 501 502 return kxsd9_power_up(st); 503 } 504 505 EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend, 506 kxsd9_runtime_resume, NULL, IIO_KXSD9); 507 508 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>"); 509 MODULE_DESCRIPTION("Kionix KXSD9 driver"); 510 MODULE_LICENSE("GPL v2"); 511