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 ret = -EINVAL; 151 else 152 ret = kxsd9_write_scale(indio_dev, val2); 153 } 154 155 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_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 aligned_s64 ts; 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_ts(indio_dev, &hw_values, sizeof(hw_values), 232 iio_get_time_ns(indio_dev)); 233 out: 234 iio_trigger_notify_done(indio_dev->trig); 235 236 return IRQ_HANDLED; 237 } 238 239 static int kxsd9_buffer_preenable(struct iio_dev *indio_dev) 240 { 241 struct kxsd9_state *st = iio_priv(indio_dev); 242 243 pm_runtime_get_sync(st->dev); 244 245 return 0; 246 } 247 248 static int kxsd9_buffer_postdisable(struct iio_dev *indio_dev) 249 { 250 struct kxsd9_state *st = iio_priv(indio_dev); 251 252 pm_runtime_put_autosuspend(st->dev); 253 254 return 0; 255 } 256 257 static const struct iio_buffer_setup_ops kxsd9_buffer_setup_ops = { 258 .preenable = kxsd9_buffer_preenable, 259 .postdisable = kxsd9_buffer_postdisable, 260 }; 261 262 static const struct iio_mount_matrix * 263 kxsd9_get_mount_matrix(const struct iio_dev *indio_dev, 264 const struct iio_chan_spec *chan) 265 { 266 struct kxsd9_state *st = iio_priv(indio_dev); 267 268 return &st->orientation; 269 } 270 271 static const struct iio_chan_spec_ext_info kxsd9_ext_info[] = { 272 IIO_MOUNT_MATRIX(IIO_SHARED_BY_TYPE, kxsd9_get_mount_matrix), 273 { } 274 }; 275 276 #define KXSD9_ACCEL_CHAN(axis, index) \ 277 { \ 278 .type = IIO_ACCEL, \ 279 .modified = 1, \ 280 .channel2 = IIO_MOD_##axis, \ 281 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ 282 .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \ 283 BIT(IIO_CHAN_INFO_OFFSET), \ 284 .ext_info = kxsd9_ext_info, \ 285 .address = KXSD9_REG_##axis, \ 286 .scan_index = index, \ 287 .scan_type = { \ 288 .sign = 'u', \ 289 .realbits = 12, \ 290 .storagebits = 16, \ 291 .shift = 4, \ 292 .endianness = IIO_BE, \ 293 }, \ 294 } 295 296 static const struct iio_chan_spec kxsd9_channels[] = { 297 KXSD9_ACCEL_CHAN(X, 0), 298 KXSD9_ACCEL_CHAN(Y, 1), 299 KXSD9_ACCEL_CHAN(Z, 2), 300 { 301 .type = IIO_VOLTAGE, 302 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), 303 .indexed = 1, 304 .address = KXSD9_REG_AUX, 305 .scan_index = 3, 306 .scan_type = { 307 .sign = 'u', 308 .realbits = 12, 309 .storagebits = 16, 310 .shift = 4, 311 .endianness = IIO_BE, 312 }, 313 }, 314 IIO_CHAN_SOFT_TIMESTAMP(4), 315 }; 316 317 static const struct attribute_group kxsd9_attribute_group = { 318 .attrs = kxsd9_attributes, 319 }; 320 321 static int kxsd9_power_up(struct kxsd9_state *st) 322 { 323 int ret; 324 325 /* Enable the regulators */ 326 ret = regulator_bulk_enable(ARRAY_SIZE(st->regs), st->regs); 327 if (ret) { 328 dev_err(st->dev, "Cannot enable regulators\n"); 329 return ret; 330 } 331 332 /* Power up */ 333 ret = regmap_write(st->map, 334 KXSD9_REG_CTRL_B, 335 KXSD9_CTRL_B_ENABLE); 336 if (ret) 337 return ret; 338 339 /* 340 * Set 1000Hz LPF, 2g fullscale, motion wakeup threshold 1g, 341 * latched wakeup 342 */ 343 ret = regmap_write(st->map, 344 KXSD9_REG_CTRL_C, 345 KXSD9_CTRL_C_LP_1000HZ | 346 KXSD9_CTRL_C_MOT_LEV | 347 KXSD9_CTRL_C_MOT_LAT | 348 st->scale); 349 if (ret) 350 return ret; 351 352 /* 353 * Power-up time depends on the LPF setting, but typ 15.9 ms, let's 354 * set 20 ms to allow for some slack. 355 */ 356 msleep(20); 357 358 return 0; 359 }; 360 361 static int kxsd9_power_down(struct kxsd9_state *st) 362 { 363 int ret; 364 365 /* 366 * Set into low power mode - since there may be more users of the 367 * regulators this is the first step of the power saving: it will 368 * make sure we conserve power even if there are others users on the 369 * regulators. 370 */ 371 ret = regmap_clear_bits(st->map, KXSD9_REG_CTRL_B, KXSD9_CTRL_B_ENABLE); 372 if (ret) 373 return ret; 374 375 /* Disable the regulators */ 376 ret = regulator_bulk_disable(ARRAY_SIZE(st->regs), st->regs); 377 if (ret) { 378 dev_err(st->dev, "Cannot disable regulators\n"); 379 return ret; 380 } 381 382 return 0; 383 } 384 385 static const struct iio_info kxsd9_info = { 386 .read_raw = &kxsd9_read_raw, 387 .write_raw = &kxsd9_write_raw, 388 .attrs = &kxsd9_attribute_group, 389 }; 390 391 /* Four channels apart from timestamp, scan mask = 0x0f */ 392 static const unsigned long kxsd9_scan_masks[] = { 0xf, 0 }; 393 394 int kxsd9_common_probe(struct device *dev, 395 struct regmap *map, 396 const char *name) 397 { 398 struct iio_dev *indio_dev; 399 struct kxsd9_state *st; 400 int ret; 401 402 indio_dev = devm_iio_device_alloc(dev, sizeof(*st)); 403 if (!indio_dev) 404 return -ENOMEM; 405 406 st = iio_priv(indio_dev); 407 st->dev = dev; 408 st->map = map; 409 410 indio_dev->channels = kxsd9_channels; 411 indio_dev->num_channels = ARRAY_SIZE(kxsd9_channels); 412 indio_dev->name = name; 413 indio_dev->info = &kxsd9_info; 414 indio_dev->modes = INDIO_DIRECT_MODE; 415 indio_dev->available_scan_masks = kxsd9_scan_masks; 416 417 /* Read the mounting matrix, if present */ 418 ret = iio_read_mount_matrix(dev, &st->orientation); 419 if (ret) 420 return ret; 421 422 /* Fetch and turn on regulators */ 423 st->regs[0].supply = kxsd9_reg_vdd; 424 st->regs[1].supply = kxsd9_reg_iovdd; 425 ret = devm_regulator_bulk_get(dev, 426 ARRAY_SIZE(st->regs), 427 st->regs); 428 if (ret) { 429 dev_err(dev, "Cannot get regulators\n"); 430 return ret; 431 } 432 /* Default scaling */ 433 st->scale = KXSD9_CTRL_C_FS_2G; 434 435 kxsd9_power_up(st); 436 437 ret = iio_triggered_buffer_setup(indio_dev, 438 iio_pollfunc_store_time, 439 kxsd9_trigger_handler, 440 &kxsd9_buffer_setup_ops); 441 if (ret) { 442 dev_err(dev, "triggered buffer setup failed\n"); 443 goto err_power_down; 444 } 445 446 ret = iio_device_register(indio_dev); 447 if (ret) 448 goto err_cleanup_buffer; 449 450 dev_set_drvdata(dev, indio_dev); 451 452 /* Enable runtime PM */ 453 pm_runtime_get_noresume(dev); 454 pm_runtime_set_active(dev); 455 pm_runtime_enable(dev); 456 /* 457 * Set autosuspend to two orders of magnitude larger than the 458 * start-up time. 20ms start-up time means 2000ms autosuspend, 459 * i.e. 2 seconds. 460 */ 461 pm_runtime_set_autosuspend_delay(dev, 2000); 462 pm_runtime_use_autosuspend(dev); 463 pm_runtime_put(dev); 464 465 return 0; 466 467 err_cleanup_buffer: 468 iio_triggered_buffer_cleanup(indio_dev); 469 err_power_down: 470 kxsd9_power_down(st); 471 472 return ret; 473 } 474 EXPORT_SYMBOL_NS(kxsd9_common_probe, "IIO_KXSD9"); 475 476 void kxsd9_common_remove(struct device *dev) 477 { 478 struct iio_dev *indio_dev = dev_get_drvdata(dev); 479 struct kxsd9_state *st = iio_priv(indio_dev); 480 481 iio_triggered_buffer_cleanup(indio_dev); 482 iio_device_unregister(indio_dev); 483 pm_runtime_get_sync(dev); 484 pm_runtime_put_noidle(dev); 485 pm_runtime_disable(dev); 486 kxsd9_power_down(st); 487 } 488 EXPORT_SYMBOL_NS(kxsd9_common_remove, "IIO_KXSD9"); 489 490 static int kxsd9_runtime_suspend(struct device *dev) 491 { 492 struct iio_dev *indio_dev = dev_get_drvdata(dev); 493 struct kxsd9_state *st = iio_priv(indio_dev); 494 495 return kxsd9_power_down(st); 496 } 497 498 static int kxsd9_runtime_resume(struct device *dev) 499 { 500 struct iio_dev *indio_dev = dev_get_drvdata(dev); 501 struct kxsd9_state *st = iio_priv(indio_dev); 502 503 return kxsd9_power_up(st); 504 } 505 506 EXPORT_NS_RUNTIME_DEV_PM_OPS(kxsd9_dev_pm_ops, kxsd9_runtime_suspend, 507 kxsd9_runtime_resume, NULL, IIO_KXSD9); 508 509 MODULE_AUTHOR("Jonathan Cameron <jic23@kernel.org>"); 510 MODULE_DESCRIPTION("Kionix KXSD9 driver"); 511 MODULE_LICENSE("GPL v2"); 512