1 2 /* The industrial I/O core 3 * 4 * Copyright (c) 2008 Jonathan Cameron 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 as published by 8 * the Free Software Foundation. 9 */ 10 #ifndef _INDUSTRIAL_IO_H_ 11 #define _INDUSTRIAL_IO_H_ 12 13 #include <linux/device.h> 14 #include <linux/cdev.h> 15 #include <linux/iio/types.h> 16 #include <linux/of.h> 17 /* IIO TODO LIST */ 18 /* 19 * Provide means of adjusting timer accuracy. 20 * Currently assumes nano seconds. 21 */ 22 23 enum iio_chan_info_enum { 24 IIO_CHAN_INFO_RAW = 0, 25 IIO_CHAN_INFO_PROCESSED, 26 IIO_CHAN_INFO_SCALE, 27 IIO_CHAN_INFO_OFFSET, 28 IIO_CHAN_INFO_CALIBSCALE, 29 IIO_CHAN_INFO_CALIBBIAS, 30 IIO_CHAN_INFO_PEAK, 31 IIO_CHAN_INFO_PEAK_SCALE, 32 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW, 33 IIO_CHAN_INFO_AVERAGE_RAW, 34 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY, 35 IIO_CHAN_INFO_SAMP_FREQ, 36 IIO_CHAN_INFO_FREQUENCY, 37 IIO_CHAN_INFO_PHASE, 38 IIO_CHAN_INFO_HARDWAREGAIN, 39 IIO_CHAN_INFO_HYSTERESIS, 40 IIO_CHAN_INFO_INT_TIME, 41 IIO_CHAN_INFO_ENABLE, 42 IIO_CHAN_INFO_CALIBHEIGHT, 43 IIO_CHAN_INFO_CALIBWEIGHT, 44 IIO_CHAN_INFO_DEBOUNCE_COUNT, 45 IIO_CHAN_INFO_DEBOUNCE_TIME, 46 }; 47 48 enum iio_shared_by { 49 IIO_SEPARATE, 50 IIO_SHARED_BY_TYPE, 51 IIO_SHARED_BY_DIR, 52 IIO_SHARED_BY_ALL 53 }; 54 55 enum iio_endian { 56 IIO_CPU, 57 IIO_BE, 58 IIO_LE, 59 }; 60 61 struct iio_chan_spec; 62 struct iio_dev; 63 64 /** 65 * struct iio_chan_spec_ext_info - Extended channel info attribute 66 * @name: Info attribute name 67 * @shared: Whether this attribute is shared between all channels. 68 * @read: Read callback for this info attribute, may be NULL. 69 * @write: Write callback for this info attribute, may be NULL. 70 * @private: Data private to the driver. 71 */ 72 struct iio_chan_spec_ext_info { 73 const char *name; 74 enum iio_shared_by shared; 75 ssize_t (*read)(struct iio_dev *, uintptr_t private, 76 struct iio_chan_spec const *, char *buf); 77 ssize_t (*write)(struct iio_dev *, uintptr_t private, 78 struct iio_chan_spec const *, const char *buf, 79 size_t len); 80 uintptr_t private; 81 }; 82 83 /** 84 * struct iio_enum - Enum channel info attribute 85 * @items: An array of strings. 86 * @num_items: Length of the item array. 87 * @set: Set callback function, may be NULL. 88 * @get: Get callback function, may be NULL. 89 * 90 * The iio_enum struct can be used to implement enum style channel attributes. 91 * Enum style attributes are those which have a set of strings which map to 92 * unsigned integer values. The IIO enum helper code takes care of mapping 93 * between value and string as well as generating a "_available" file which 94 * contains a list of all available items. The set callback will be called when 95 * the attribute is updated. The last parameter is the index to the newly 96 * activated item. The get callback will be used to query the currently active 97 * item and is supposed to return the index for it. 98 */ 99 struct iio_enum { 100 const char * const *items; 101 unsigned int num_items; 102 int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int); 103 int (*get)(struct iio_dev *, const struct iio_chan_spec *); 104 }; 105 106 ssize_t iio_enum_available_read(struct iio_dev *indio_dev, 107 uintptr_t priv, const struct iio_chan_spec *chan, char *buf); 108 ssize_t iio_enum_read(struct iio_dev *indio_dev, 109 uintptr_t priv, const struct iio_chan_spec *chan, char *buf); 110 ssize_t iio_enum_write(struct iio_dev *indio_dev, 111 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf, 112 size_t len); 113 114 /** 115 * IIO_ENUM() - Initialize enum extended channel attribute 116 * @_name: Attribute name 117 * @_shared: Whether the attribute is shared between all channels 118 * @_e: Pointer to an iio_enum struct 119 * 120 * This should usually be used together with IIO_ENUM_AVAILABLE() 121 */ 122 #define IIO_ENUM(_name, _shared, _e) \ 123 { \ 124 .name = (_name), \ 125 .shared = (_shared), \ 126 .read = iio_enum_read, \ 127 .write = iio_enum_write, \ 128 .private = (uintptr_t)(_e), \ 129 } 130 131 /** 132 * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute 133 * @_name: Attribute name ("_available" will be appended to the name) 134 * @_e: Pointer to an iio_enum struct 135 * 136 * Creates a read only attribute which lists all the available enum items in a 137 * space separated list. This should usually be used together with IIO_ENUM() 138 */ 139 #define IIO_ENUM_AVAILABLE(_name, _e) \ 140 { \ 141 .name = (_name "_available"), \ 142 .shared = IIO_SHARED_BY_TYPE, \ 143 .read = iio_enum_available_read, \ 144 .private = (uintptr_t)(_e), \ 145 } 146 147 /** 148 * struct iio_event_spec - specification for a channel event 149 * @type: Type of the event 150 * @dir: Direction of the event 151 * @mask_separate: Bit mask of enum iio_event_info values. Attributes 152 * set in this mask will be registered per channel. 153 * @mask_shared_by_type: Bit mask of enum iio_event_info values. Attributes 154 * set in this mask will be shared by channel type. 155 * @mask_shared_by_dir: Bit mask of enum iio_event_info values. Attributes 156 * set in this mask will be shared by channel type and 157 * direction. 158 * @mask_shared_by_all: Bit mask of enum iio_event_info values. Attributes 159 * set in this mask will be shared by all channels. 160 */ 161 struct iio_event_spec { 162 enum iio_event_type type; 163 enum iio_event_direction dir; 164 unsigned long mask_separate; 165 unsigned long mask_shared_by_type; 166 unsigned long mask_shared_by_dir; 167 unsigned long mask_shared_by_all; 168 }; 169 170 /** 171 * struct iio_chan_spec - specification of a single channel 172 * @type: What type of measurement is the channel making. 173 * @channel: What number do we wish to assign the channel. 174 * @channel2: If there is a second number for a differential 175 * channel then this is it. If modified is set then the 176 * value here specifies the modifier. 177 * @address: Driver specific identifier. 178 * @scan_index: Monotonic index to give ordering in scans when read 179 * from a buffer. 180 * @scan_type: Sign: 's' or 'u' to specify signed or unsigned 181 * realbits: Number of valid bits of data 182 * storage_bits: Realbits + padding 183 * shift: Shift right by this before masking out 184 * realbits. 185 * endianness: little or big endian 186 * repeat: Number of times real/storage bits 187 * repeats. When the repeat element is 188 * more than 1, then the type element in 189 * sysfs will show a repeat value. 190 * Otherwise, the number of repetitions is 191 * omitted. 192 * @info_mask_separate: What information is to be exported that is specific to 193 * this channel. 194 * @info_mask_shared_by_type: What information is to be exported that is shared 195 * by all channels of the same type. 196 * @info_mask_shared_by_dir: What information is to be exported that is shared 197 * by all channels of the same direction. 198 * @info_mask_shared_by_all: What information is to be exported that is shared 199 * by all channels. 200 * @event_spec: Array of events which should be registered for this 201 * channel. 202 * @num_event_specs: Size of the event_spec array. 203 * @ext_info: Array of extended info attributes for this channel. 204 * The array is NULL terminated, the last element should 205 * have its name field set to NULL. 206 * @extend_name: Allows labeling of channel attributes with an 207 * informative name. Note this has no effect codes etc, 208 * unlike modifiers. 209 * @datasheet_name: A name used in in-kernel mapping of channels. It should 210 * correspond to the first name that the channel is referred 211 * to by in the datasheet (e.g. IND), or the nearest 212 * possible compound name (e.g. IND-INC). 213 * @modified: Does a modifier apply to this channel. What these are 214 * depends on the channel type. Modifier is set in 215 * channel2. Examples are IIO_MOD_X for axial sensors about 216 * the 'x' axis. 217 * @indexed: Specify the channel has a numerical index. If not, 218 * the channel index number will be suppressed for sysfs 219 * attributes but not for event codes. 220 * @output: Channel is output. 221 * @differential: Channel is differential. 222 */ 223 struct iio_chan_spec { 224 enum iio_chan_type type; 225 int channel; 226 int channel2; 227 unsigned long address; 228 int scan_index; 229 struct { 230 char sign; 231 u8 realbits; 232 u8 storagebits; 233 u8 shift; 234 u8 repeat; 235 enum iio_endian endianness; 236 } scan_type; 237 long info_mask_separate; 238 long info_mask_shared_by_type; 239 long info_mask_shared_by_dir; 240 long info_mask_shared_by_all; 241 const struct iio_event_spec *event_spec; 242 unsigned int num_event_specs; 243 const struct iio_chan_spec_ext_info *ext_info; 244 const char *extend_name; 245 const char *datasheet_name; 246 unsigned modified:1; 247 unsigned indexed:1; 248 unsigned output:1; 249 unsigned differential:1; 250 }; 251 252 253 /** 254 * iio_channel_has_info() - Checks whether a channel supports a info attribute 255 * @chan: The channel to be queried 256 * @type: Type of the info attribute to be checked 257 * 258 * Returns true if the channels supports reporting values for the given info 259 * attribute type, false otherwise. 260 */ 261 static inline bool iio_channel_has_info(const struct iio_chan_spec *chan, 262 enum iio_chan_info_enum type) 263 { 264 return (chan->info_mask_separate & BIT(type)) | 265 (chan->info_mask_shared_by_type & BIT(type)) | 266 (chan->info_mask_shared_by_dir & BIT(type)) | 267 (chan->info_mask_shared_by_all & BIT(type)); 268 } 269 270 #define IIO_CHAN_SOFT_TIMESTAMP(_si) { \ 271 .type = IIO_TIMESTAMP, \ 272 .channel = -1, \ 273 .scan_index = _si, \ 274 .scan_type = { \ 275 .sign = 's', \ 276 .realbits = 64, \ 277 .storagebits = 64, \ 278 }, \ 279 } 280 281 /** 282 * iio_get_time_ns() - utility function to get a time stamp for events etc 283 **/ 284 static inline s64 iio_get_time_ns(void) 285 { 286 return ktime_get_real_ns(); 287 } 288 289 /* Device operating modes */ 290 #define INDIO_DIRECT_MODE 0x01 291 #define INDIO_BUFFER_TRIGGERED 0x02 292 #define INDIO_BUFFER_SOFTWARE 0x04 293 #define INDIO_BUFFER_HARDWARE 0x08 294 295 #define INDIO_ALL_BUFFER_MODES \ 296 (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE | INDIO_BUFFER_SOFTWARE) 297 298 #define INDIO_MAX_RAW_ELEMENTS 4 299 300 struct iio_trigger; /* forward declaration */ 301 struct iio_dev; 302 303 /** 304 * struct iio_info - constant information about device 305 * @driver_module: module structure used to ensure correct 306 * ownership of chrdevs etc 307 * @event_attrs: event control attributes 308 * @attrs: general purpose device attributes 309 * @read_raw: function to request a value from the device. 310 * mask specifies which value. Note 0 means a reading of 311 * the channel in question. Return value will specify the 312 * type of value returned by the device. val and val2 will 313 * contain the elements making up the returned value. 314 * @read_raw_multi: function to return values from the device. 315 * mask specifies which value. Note 0 means a reading of 316 * the channel in question. Return value will specify the 317 * type of value returned by the device. vals pointer 318 * contain the elements making up the returned value. 319 * max_len specifies maximum number of elements 320 * vals pointer can contain. val_len is used to return 321 * length of valid elements in vals. 322 * @write_raw: function to write a value to the device. 323 * Parameters are the same as for read_raw. 324 * @write_raw_get_fmt: callback function to query the expected 325 * format/precision. If not set by the driver, write_raw 326 * returns IIO_VAL_INT_PLUS_MICRO. 327 * @read_event_config: find out if the event is enabled. 328 * @write_event_config: set if the event is enabled. 329 * @read_event_value: read a configuration value associated with the event. 330 * @write_event_value: write a configuration value for the event. 331 * @validate_trigger: function to validate the trigger when the 332 * current trigger gets changed. 333 * @update_scan_mode: function to configure device and scan buffer when 334 * channels have changed 335 * @debugfs_reg_access: function to read or write register value of device 336 * @of_xlate: function pointer to obtain channel specifier index. 337 * When #iio-cells is greater than '0', the driver could 338 * provide a custom of_xlate function that reads the 339 * *args* and returns the appropriate index in registered 340 * IIO channels array. 341 **/ 342 struct iio_info { 343 struct module *driver_module; 344 struct attribute_group *event_attrs; 345 const struct attribute_group *attrs; 346 347 int (*read_raw)(struct iio_dev *indio_dev, 348 struct iio_chan_spec const *chan, 349 int *val, 350 int *val2, 351 long mask); 352 353 int (*read_raw_multi)(struct iio_dev *indio_dev, 354 struct iio_chan_spec const *chan, 355 int max_len, 356 int *vals, 357 int *val_len, 358 long mask); 359 360 int (*write_raw)(struct iio_dev *indio_dev, 361 struct iio_chan_spec const *chan, 362 int val, 363 int val2, 364 long mask); 365 366 int (*write_raw_get_fmt)(struct iio_dev *indio_dev, 367 struct iio_chan_spec const *chan, 368 long mask); 369 370 int (*read_event_config)(struct iio_dev *indio_dev, 371 const struct iio_chan_spec *chan, 372 enum iio_event_type type, 373 enum iio_event_direction dir); 374 375 int (*write_event_config)(struct iio_dev *indio_dev, 376 const struct iio_chan_spec *chan, 377 enum iio_event_type type, 378 enum iio_event_direction dir, 379 int state); 380 381 int (*read_event_value)(struct iio_dev *indio_dev, 382 const struct iio_chan_spec *chan, 383 enum iio_event_type type, 384 enum iio_event_direction dir, 385 enum iio_event_info info, int *val, int *val2); 386 387 int (*write_event_value)(struct iio_dev *indio_dev, 388 const struct iio_chan_spec *chan, 389 enum iio_event_type type, 390 enum iio_event_direction dir, 391 enum iio_event_info info, int val, int val2); 392 393 int (*validate_trigger)(struct iio_dev *indio_dev, 394 struct iio_trigger *trig); 395 int (*update_scan_mode)(struct iio_dev *indio_dev, 396 const unsigned long *scan_mask); 397 int (*debugfs_reg_access)(struct iio_dev *indio_dev, 398 unsigned reg, unsigned writeval, 399 unsigned *readval); 400 int (*of_xlate)(struct iio_dev *indio_dev, 401 const struct of_phandle_args *iiospec); 402 }; 403 404 /** 405 * struct iio_buffer_setup_ops - buffer setup related callbacks 406 * @preenable: [DRIVER] function to run prior to marking buffer enabled 407 * @postenable: [DRIVER] function to run after marking buffer enabled 408 * @predisable: [DRIVER] function to run prior to marking buffer 409 * disabled 410 * @postdisable: [DRIVER] function to run after marking buffer disabled 411 * @validate_scan_mask: [DRIVER] function callback to check whether a given 412 * scan mask is valid for the device. 413 */ 414 struct iio_buffer_setup_ops { 415 int (*preenable)(struct iio_dev *); 416 int (*postenable)(struct iio_dev *); 417 int (*predisable)(struct iio_dev *); 418 int (*postdisable)(struct iio_dev *); 419 bool (*validate_scan_mask)(struct iio_dev *indio_dev, 420 const unsigned long *scan_mask); 421 }; 422 423 /** 424 * struct iio_dev - industrial I/O device 425 * @id: [INTERN] used to identify device internally 426 * @modes: [DRIVER] operating modes supported by device 427 * @currentmode: [DRIVER] current operating mode 428 * @dev: [DRIVER] device structure, should be assigned a parent 429 * and owner 430 * @event_interface: [INTERN] event chrdevs associated with interrupt lines 431 * @buffer: [DRIVER] any buffer present 432 * @buffer_list: [INTERN] list of all buffers currently attached 433 * @scan_bytes: [INTERN] num bytes captured to be fed to buffer demux 434 * @mlock: [INTERN] lock used to prevent simultaneous device state 435 * changes 436 * @available_scan_masks: [DRIVER] optional array of allowed bitmasks 437 * @masklength: [INTERN] the length of the mask established from 438 * channels 439 * @active_scan_mask: [INTERN] union of all scan masks requested by buffers 440 * @scan_timestamp: [INTERN] set if any buffers have requested timestamp 441 * @scan_index_timestamp:[INTERN] cache of the index to the timestamp 442 * @trig: [INTERN] current device trigger (buffer modes) 443 * @pollfunc: [DRIVER] function run on trigger being received 444 * @channels: [DRIVER] channel specification structure table 445 * @num_channels: [DRIVER] number of channels specified in @channels. 446 * @channel_attr_list: [INTERN] keep track of automatically created channel 447 * attributes 448 * @chan_attr_group: [INTERN] group for all attrs in base directory 449 * @name: [DRIVER] name of the device. 450 * @info: [DRIVER] callbacks and constant info from driver 451 * @info_exist_lock: [INTERN] lock to prevent use during removal 452 * @setup_ops: [DRIVER] callbacks to call before and after buffer 453 * enable/disable 454 * @chrdev: [INTERN] associated character device 455 * @groups: [INTERN] attribute groups 456 * @groupcounter: [INTERN] index of next attribute group 457 * @flags: [INTERN] file ops related flags including busy flag. 458 * @debugfs_dentry: [INTERN] device specific debugfs dentry. 459 * @cached_reg_addr: [INTERN] cached register address for debugfs reads. 460 */ 461 struct iio_dev { 462 int id; 463 464 int modes; 465 int currentmode; 466 struct device dev; 467 468 struct iio_event_interface *event_interface; 469 470 struct iio_buffer *buffer; 471 struct list_head buffer_list; 472 int scan_bytes; 473 struct mutex mlock; 474 475 const unsigned long *available_scan_masks; 476 unsigned masklength; 477 const unsigned long *active_scan_mask; 478 bool scan_timestamp; 479 unsigned scan_index_timestamp; 480 struct iio_trigger *trig; 481 struct iio_poll_func *pollfunc; 482 483 struct iio_chan_spec const *channels; 484 int num_channels; 485 486 struct list_head channel_attr_list; 487 struct attribute_group chan_attr_group; 488 const char *name; 489 const struct iio_info *info; 490 struct mutex info_exist_lock; 491 const struct iio_buffer_setup_ops *setup_ops; 492 struct cdev chrdev; 493 #define IIO_MAX_GROUPS 6 494 const struct attribute_group *groups[IIO_MAX_GROUPS + 1]; 495 int groupcounter; 496 497 unsigned long flags; 498 #if defined(CONFIG_DEBUG_FS) 499 struct dentry *debugfs_dentry; 500 unsigned cached_reg_addr; 501 #endif 502 }; 503 504 const struct iio_chan_spec 505 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si); 506 int iio_device_register(struct iio_dev *indio_dev); 507 void iio_device_unregister(struct iio_dev *indio_dev); 508 int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev); 509 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev); 510 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp); 511 512 extern struct bus_type iio_bus_type; 513 514 /** 515 * iio_device_put() - reference counted deallocation of struct device 516 * @indio_dev: IIO device structure containing the device 517 **/ 518 static inline void iio_device_put(struct iio_dev *indio_dev) 519 { 520 if (indio_dev) 521 put_device(&indio_dev->dev); 522 } 523 524 /** 525 * dev_to_iio_dev() - Get IIO device struct from a device struct 526 * @dev: The device embedded in the IIO device 527 * 528 * Note: The device must be a IIO device, otherwise the result is undefined. 529 */ 530 static inline struct iio_dev *dev_to_iio_dev(struct device *dev) 531 { 532 return container_of(dev, struct iio_dev, dev); 533 } 534 535 /** 536 * iio_device_get() - increment reference count for the device 537 * @indio_dev: IIO device structure 538 * 539 * Returns: The passed IIO device 540 **/ 541 static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev) 542 { 543 return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL; 544 } 545 546 547 /** 548 * iio_device_set_drvdata() - Set device driver data 549 * @indio_dev: IIO device structure 550 * @data: Driver specific data 551 * 552 * Allows to attach an arbitrary pointer to an IIO device, which can later be 553 * retrieved by iio_device_get_drvdata(). 554 */ 555 static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data) 556 { 557 dev_set_drvdata(&indio_dev->dev, data); 558 } 559 560 /** 561 * iio_device_get_drvdata() - Get device driver data 562 * @indio_dev: IIO device structure 563 * 564 * Returns the data previously set with iio_device_set_drvdata() 565 */ 566 static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev) 567 { 568 return dev_get_drvdata(&indio_dev->dev); 569 } 570 571 /* Can we make this smaller? */ 572 #define IIO_ALIGN L1_CACHE_BYTES 573 struct iio_dev *iio_device_alloc(int sizeof_priv); 574 575 static inline void *iio_priv(const struct iio_dev *indio_dev) 576 { 577 return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN); 578 } 579 580 static inline struct iio_dev *iio_priv_to_dev(void *priv) 581 { 582 return (struct iio_dev *)((char *)priv - 583 ALIGN(sizeof(struct iio_dev), IIO_ALIGN)); 584 } 585 586 void iio_device_free(struct iio_dev *indio_dev); 587 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv); 588 void devm_iio_device_free(struct device *dev, struct iio_dev *indio_dev); 589 struct iio_trigger *devm_iio_trigger_alloc(struct device *dev, 590 const char *fmt, ...); 591 void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig); 592 593 /** 594 * iio_buffer_enabled() - helper function to test if the buffer is enabled 595 * @indio_dev: IIO device structure for device 596 **/ 597 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev) 598 { 599 return indio_dev->currentmode 600 & (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE | 601 INDIO_BUFFER_SOFTWARE); 602 } 603 604 /** 605 * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry 606 * @indio_dev: IIO device structure for device 607 **/ 608 #if defined(CONFIG_DEBUG_FS) 609 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev) 610 { 611 return indio_dev->debugfs_dentry; 612 } 613 #else 614 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev) 615 { 616 return NULL; 617 } 618 #endif 619 620 int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer, 621 int *fract); 622 623 /** 624 * IIO_DEGREE_TO_RAD() - Convert degree to rad 625 * @deg: A value in degree 626 * 627 * Returns the given value converted from degree to rad 628 */ 629 #define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL) 630 631 /** 632 * IIO_G_TO_M_S_2() - Convert g to meter / second**2 633 * @g: A value in g 634 * 635 * Returns the given value converted from g to meter / second**2 636 */ 637 #define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL) 638 639 #endif /* _INDUSTRIAL_IO_H_ */ 640