xref: /linux/include/linux/iio/iio.h (revision f58c91ce82cbb55a48fbc1a0cb7c84c0d0a4e1bd)
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 /* IIO TODO LIST */
17 /*
18  * Provide means of adjusting timer accuracy.
19  * Currently assumes nano seconds.
20  */
21 
22 enum iio_chan_info_enum {
23 	IIO_CHAN_INFO_RAW = 0,
24 	IIO_CHAN_INFO_PROCESSED,
25 	IIO_CHAN_INFO_SCALE,
26 	IIO_CHAN_INFO_OFFSET,
27 	IIO_CHAN_INFO_CALIBSCALE,
28 	IIO_CHAN_INFO_CALIBBIAS,
29 	IIO_CHAN_INFO_PEAK,
30 	IIO_CHAN_INFO_PEAK_SCALE,
31 	IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW,
32 	IIO_CHAN_INFO_AVERAGE_RAW,
33 	IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY,
34 	IIO_CHAN_INFO_SAMP_FREQ,
35 	IIO_CHAN_INFO_FREQUENCY,
36 	IIO_CHAN_INFO_PHASE,
37 	IIO_CHAN_INFO_HARDWAREGAIN,
38 	IIO_CHAN_INFO_HYSTERESIS,
39 	IIO_CHAN_INFO_INT_TIME,
40 };
41 
42 enum iio_shared_by {
43 	IIO_SEPARATE,
44 	IIO_SHARED_BY_TYPE,
45 	IIO_SHARED_BY_DIR,
46 	IIO_SHARED_BY_ALL
47 };
48 
49 enum iio_endian {
50 	IIO_CPU,
51 	IIO_BE,
52 	IIO_LE,
53 };
54 
55 struct iio_chan_spec;
56 struct iio_dev;
57 
58 /**
59  * struct iio_chan_spec_ext_info - Extended channel info attribute
60  * @name:	Info attribute name
61  * @shared:	Whether this attribute is shared between all channels.
62  * @read:	Read callback for this info attribute, may be NULL.
63  * @write:	Write callback for this info attribute, may be NULL.
64  * @private:	Data private to the driver.
65  */
66 struct iio_chan_spec_ext_info {
67 	const char *name;
68 	enum iio_shared_by shared;
69 	ssize_t (*read)(struct iio_dev *, uintptr_t private,
70 			struct iio_chan_spec const *, char *buf);
71 	ssize_t (*write)(struct iio_dev *, uintptr_t private,
72 			 struct iio_chan_spec const *, const char *buf,
73 			 size_t len);
74 	uintptr_t private;
75 };
76 
77 /**
78  * struct iio_enum - Enum channel info attribute
79  * @items:	An array of strings.
80  * @num_items:	Length of the item array.
81  * @set:	Set callback function, may be NULL.
82  * @get:	Get callback function, may be NULL.
83  *
84  * The iio_enum struct can be used to implement enum style channel attributes.
85  * Enum style attributes are those which have a set of strings which map to
86  * unsigned integer values. The IIO enum helper code takes care of mapping
87  * between value and string as well as generating a "_available" file which
88  * contains a list of all available items. The set callback will be called when
89  * the attribute is updated. The last parameter is the index to the newly
90  * activated item. The get callback will be used to query the currently active
91  * item and is supposed to return the index for it.
92  */
93 struct iio_enum {
94 	const char * const *items;
95 	unsigned int num_items;
96 	int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
97 	int (*get)(struct iio_dev *, const struct iio_chan_spec *);
98 };
99 
100 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
101 	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
102 ssize_t iio_enum_read(struct iio_dev *indio_dev,
103 	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
104 ssize_t iio_enum_write(struct iio_dev *indio_dev,
105 	uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
106 	size_t len);
107 
108 /**
109  * IIO_ENUM() - Initialize enum extended channel attribute
110  * @_name:	Attribute name
111  * @_shared:	Whether the attribute is shared between all channels
112  * @_e:		Pointer to an iio_enum struct
113  *
114  * This should usually be used together with IIO_ENUM_AVAILABLE()
115  */
116 #define IIO_ENUM(_name, _shared, _e) \
117 { \
118 	.name = (_name), \
119 	.shared = (_shared), \
120 	.read = iio_enum_read, \
121 	.write = iio_enum_write, \
122 	.private = (uintptr_t)(_e), \
123 }
124 
125 /**
126  * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
127  * @_name:	Attribute name ("_available" will be appended to the name)
128  * @_e:		Pointer to an iio_enum struct
129  *
130  * Creates a read only attribute which lists all the available enum items in a
131  * space separated list. This should usually be used together with IIO_ENUM()
132  */
133 #define IIO_ENUM_AVAILABLE(_name, _e) \
134 { \
135 	.name = (_name "_available"), \
136 	.shared = IIO_SHARED_BY_TYPE, \
137 	.read = iio_enum_available_read, \
138 	.private = (uintptr_t)(_e), \
139 }
140 
141 /**
142  * struct iio_event_spec - specification for a channel event
143  * @type:		    Type of the event
144  * @dir:		    Direction of the event
145  * @mask_separate:	    Bit mask of enum iio_event_info values. Attributes
146  *			    set in this mask will be registered per channel.
147  * @mask_shared_by_type:    Bit mask of enum iio_event_info values. Attributes
148  *			    set in this mask will be shared by channel type.
149  * @mask_shared_by_dir:	    Bit mask of enum iio_event_info values. Attributes
150  *			    set in this mask will be shared by channel type and
151  *			    direction.
152  * @mask_shared_by_all:	    Bit mask of enum iio_event_info values. Attributes
153  *			    set in this mask will be shared by all channels.
154  */
155 struct iio_event_spec {
156 	enum iio_event_type type;
157 	enum iio_event_direction dir;
158 	unsigned long mask_separate;
159 	unsigned long mask_shared_by_type;
160 	unsigned long mask_shared_by_dir;
161 	unsigned long mask_shared_by_all;
162 };
163 
164 /**
165  * struct iio_chan_spec - specification of a single channel
166  * @type:		What type of measurement is the channel making.
167  * @channel:		What number do we wish to assign the channel.
168  * @channel2:		If there is a second number for a differential
169  *			channel then this is it. If modified is set then the
170  *			value here specifies the modifier.
171  * @address:		Driver specific identifier.
172  * @scan_index:		Monotonic index to give ordering in scans when read
173  *			from a buffer.
174  * @scan_type:		Sign:		's' or 'u' to specify signed or unsigned
175  *			realbits:	Number of valid bits of data
176  *			storage_bits:	Realbits + padding
177  *			shift:		Shift right by this before masking out
178  *					realbits.
179  *			endianness:	little or big endian
180  * @info_mask_separate: What information is to be exported that is specific to
181  *			this channel.
182  * @info_mask_shared_by_type: What information is to be exported that is shared
183  *			by all channels of the same type.
184  * @info_mask_shared_by_dir: What information is to be exported that is shared
185  *			by all channels of the same direction.
186  * @info_mask_shared_by_all: What information is to be exported that is shared
187  *			by all channels.
188  * @event_mask:		What events can this channel produce.
189  * @event_spec:		Array of events which should be registered for this
190  *			channel.
191  * @num_event_specs:	Size of the event_spec array.
192  * @ext_info:		Array of extended info attributes for this channel.
193  *			The array is NULL terminated, the last element should
194  *			have its name field set to NULL.
195  * @extend_name:	Allows labeling of channel attributes with an
196  *			informative name. Note this has no effect codes etc,
197  *			unlike modifiers.
198  * @datasheet_name:	A name used in in-kernel mapping of channels. It should
199  *			correspond to the first name that the channel is referred
200  *			to by in the datasheet (e.g. IND), or the nearest
201  *			possible compound name (e.g. IND-INC).
202  * @modified:		Does a modifier apply to this channel. What these are
203  *			depends on the channel type.  Modifier is set in
204  *			channel2. Examples are IIO_MOD_X for axial sensors about
205  *			the 'x' axis.
206  * @indexed:		Specify the channel has a numerical index. If not,
207  *			the channel index number will be suppressed for sysfs
208  *			attributes but not for event codes.
209  * @output:		Channel is output.
210  * @differential:	Channel is differential.
211  */
212 struct iio_chan_spec {
213 	enum iio_chan_type	type;
214 	int			channel;
215 	int			channel2;
216 	unsigned long		address;
217 	int			scan_index;
218 	struct {
219 		char	sign;
220 		u8	realbits;
221 		u8	storagebits;
222 		u8	shift;
223 		enum iio_endian endianness;
224 	} scan_type;
225 	long			info_mask_separate;
226 	long			info_mask_shared_by_type;
227 	long			info_mask_shared_by_dir;
228 	long			info_mask_shared_by_all;
229 	long			event_mask;
230 	const struct iio_event_spec *event_spec;
231 	unsigned int		num_event_specs;
232 	const struct iio_chan_spec_ext_info *ext_info;
233 	const char		*extend_name;
234 	const char		*datasheet_name;
235 	unsigned		modified:1;
236 	unsigned		indexed:1;
237 	unsigned		output:1;
238 	unsigned		differential:1;
239 };
240 
241 
242 /**
243  * iio_channel_has_info() - Checks whether a channel supports a info attribute
244  * @chan: The channel to be queried
245  * @type: Type of the info attribute to be checked
246  *
247  * Returns true if the channels supports reporting values for the given info
248  * attribute type, false otherwise.
249  */
250 static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
251 	enum iio_chan_info_enum type)
252 {
253 	return (chan->info_mask_separate & BIT(type)) |
254 		(chan->info_mask_shared_by_type & BIT(type)) |
255 		(chan->info_mask_shared_by_dir & BIT(type)) |
256 		(chan->info_mask_shared_by_all & BIT(type));
257 }
258 
259 #define IIO_ST(si, rb, sb, sh)						\
260 	{ .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
261 
262 #define IIO_CHAN_SOFT_TIMESTAMP(_si)					\
263 	{ .type = IIO_TIMESTAMP, .channel = -1,				\
264 			.scan_index = _si, .scan_type = IIO_ST('s', 64, 64, 0) }
265 
266 /**
267  * iio_get_time_ns() - utility function to get a time stamp for events etc
268  **/
269 static inline s64 iio_get_time_ns(void)
270 {
271 	struct timespec ts;
272 	/*
273 	 * calls getnstimeofday.
274 	 * If hrtimers then up to ns accurate, if not microsecond.
275 	 */
276 	ktime_get_real_ts(&ts);
277 
278 	return timespec_to_ns(&ts);
279 }
280 
281 /* Device operating modes */
282 #define INDIO_DIRECT_MODE		0x01
283 #define INDIO_BUFFER_TRIGGERED		0x02
284 #define INDIO_BUFFER_HARDWARE		0x08
285 
286 #define INDIO_ALL_BUFFER_MODES					\
287 	(INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE)
288 
289 struct iio_trigger; /* forward declaration */
290 struct iio_dev;
291 
292 /**
293  * struct iio_info - constant information about device
294  * @driver_module:	module structure used to ensure correct
295  *			ownership of chrdevs etc
296  * @event_attrs:	event control attributes
297  * @attrs:		general purpose device attributes
298  * @read_raw:		function to request a value from the device.
299  *			mask specifies which value. Note 0 means a reading of
300  *			the channel in question.  Return value will specify the
301  *			type of value returned by the device. val and val2 will
302  *			contain the elements making up the returned value.
303  * @write_raw:		function to write a value to the device.
304  *			Parameters are the same as for read_raw.
305  * @write_raw_get_fmt:	callback function to query the expected
306  *			format/precision. If not set by the driver, write_raw
307  *			returns IIO_VAL_INT_PLUS_MICRO.
308  * @read_event_config:	find out if the event is enabled.
309  * @write_event_config:	set if the event is enabled.
310  * @read_event_value:	read a value associated with the event. Meaning
311  *			is event dependant. event_code specifies which event.
312  * @write_event_value:	write the value associated with the event.
313  *			Meaning is event dependent.
314  * @read_event_config_new: find out if the event is enabled. New style interface.
315  * @write_event_config_new: set if the event is enabled. New style interface.
316  * @read_event_value_new: read a configuration value associated with the event.
317  *                         New style interface.
318  * @write_event_value_new: write a configuration value for the event. New style
319  *			   interface.
320  * @validate_trigger:	function to validate the trigger when the
321  *			current trigger gets changed.
322  * @update_scan_mode:	function to configure device and scan buffer when
323  *			channels have changed
324  * @debugfs_reg_access:	function to read or write register value of device
325  **/
326 struct iio_info {
327 	struct module			*driver_module;
328 	struct attribute_group		*event_attrs;
329 	const struct attribute_group	*attrs;
330 
331 	int (*read_raw)(struct iio_dev *indio_dev,
332 			struct iio_chan_spec const *chan,
333 			int *val,
334 			int *val2,
335 			long mask);
336 
337 	int (*write_raw)(struct iio_dev *indio_dev,
338 			 struct iio_chan_spec const *chan,
339 			 int val,
340 			 int val2,
341 			 long mask);
342 
343 	int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
344 			 struct iio_chan_spec const *chan,
345 			 long mask);
346 
347 	int (*read_event_config)(struct iio_dev *indio_dev,
348 				 u64 event_code);
349 
350 	int (*write_event_config)(struct iio_dev *indio_dev,
351 				  u64 event_code,
352 				  int state);
353 
354 	int (*read_event_value)(struct iio_dev *indio_dev,
355 				u64 event_code,
356 				int *val);
357 	int (*write_event_value)(struct iio_dev *indio_dev,
358 				 u64 event_code,
359 				 int val);
360 
361 	int (*read_event_config_new)(struct iio_dev *indio_dev,
362 				 const struct iio_chan_spec *chan,
363 				 enum iio_event_type type,
364 				 enum iio_event_direction dir);
365 
366 	int (*write_event_config_new)(struct iio_dev *indio_dev,
367 				  const struct iio_chan_spec *chan,
368 				  enum iio_event_type type,
369 				  enum iio_event_direction dir,
370 				  int state);
371 
372 	int (*read_event_value_new)(struct iio_dev *indio_dev,
373 				const struct iio_chan_spec *chan,
374 				enum iio_event_type type,
375 				enum iio_event_direction dir,
376 				enum iio_event_info info, int *val, int *val2);
377 
378 	int (*write_event_value_new)(struct iio_dev *indio_dev,
379 				 const struct iio_chan_spec *chan,
380 				 enum iio_event_type type,
381 				 enum iio_event_direction dir,
382 				 enum iio_event_info info, int val, int val2);
383 
384 	int (*validate_trigger)(struct iio_dev *indio_dev,
385 				struct iio_trigger *trig);
386 	int (*update_scan_mode)(struct iio_dev *indio_dev,
387 				const unsigned long *scan_mask);
388 	int (*debugfs_reg_access)(struct iio_dev *indio_dev,
389 				  unsigned reg, unsigned writeval,
390 				  unsigned *readval);
391 };
392 
393 /**
394  * struct iio_buffer_setup_ops - buffer setup related callbacks
395  * @preenable:		[DRIVER] function to run prior to marking buffer enabled
396  * @postenable:		[DRIVER] function to run after marking buffer enabled
397  * @predisable:		[DRIVER] function to run prior to marking buffer
398  *			disabled
399  * @postdisable:	[DRIVER] function to run after marking buffer disabled
400  * @validate_scan_mask: [DRIVER] function callback to check whether a given
401  *			scan mask is valid for the device.
402  */
403 struct iio_buffer_setup_ops {
404 	int (*preenable)(struct iio_dev *);
405 	int (*postenable)(struct iio_dev *);
406 	int (*predisable)(struct iio_dev *);
407 	int (*postdisable)(struct iio_dev *);
408 	bool (*validate_scan_mask)(struct iio_dev *indio_dev,
409 				   const unsigned long *scan_mask);
410 };
411 
412 /**
413  * struct iio_dev - industrial I/O device
414  * @id:			[INTERN] used to identify device internally
415  * @modes:		[DRIVER] operating modes supported by device
416  * @currentmode:	[DRIVER] current operating mode
417  * @dev:		[DRIVER] device structure, should be assigned a parent
418  *			and owner
419  * @event_interface:	[INTERN] event chrdevs associated with interrupt lines
420  * @buffer:		[DRIVER] any buffer present
421  * @buffer_list:	[INTERN] list of all buffers currently attached
422  * @scan_bytes:		[INTERN] num bytes captured to be fed to buffer demux
423  * @mlock:		[INTERN] lock used to prevent simultaneous device state
424  *			changes
425  * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
426  * @masklength:		[INTERN] the length of the mask established from
427  *			channels
428  * @active_scan_mask:	[INTERN] union of all scan masks requested by buffers
429  * @scan_timestamp:	[INTERN] set if any buffers have requested timestamp
430  * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
431  * @trig:		[INTERN] current device trigger (buffer modes)
432  * @pollfunc:		[DRIVER] function run on trigger being received
433  * @channels:		[DRIVER] channel specification structure table
434  * @num_channels:	[DRIVER] number of channels specified in @channels.
435  * @channel_attr_list:	[INTERN] keep track of automatically created channel
436  *			attributes
437  * @chan_attr_group:	[INTERN] group for all attrs in base directory
438  * @name:		[DRIVER] name of the device.
439  * @info:		[DRIVER] callbacks and constant info from driver
440  * @info_exist_lock:	[INTERN] lock to prevent use during removal
441  * @setup_ops:		[DRIVER] callbacks to call before and after buffer
442  *			enable/disable
443  * @chrdev:		[INTERN] associated character device
444  * @groups:		[INTERN] attribute groups
445  * @groupcounter:	[INTERN] index of next attribute group
446  * @flags:		[INTERN] file ops related flags including busy flag.
447  * @debugfs_dentry:	[INTERN] device specific debugfs dentry.
448  * @cached_reg_addr:	[INTERN] cached register address for debugfs reads.
449  */
450 struct iio_dev {
451 	int				id;
452 
453 	int				modes;
454 	int				currentmode;
455 	struct device			dev;
456 
457 	struct iio_event_interface	*event_interface;
458 
459 	struct iio_buffer		*buffer;
460 	struct list_head		buffer_list;
461 	int				scan_bytes;
462 	struct mutex			mlock;
463 
464 	const unsigned long		*available_scan_masks;
465 	unsigned			masklength;
466 	const unsigned long		*active_scan_mask;
467 	bool				scan_timestamp;
468 	unsigned			scan_index_timestamp;
469 	struct iio_trigger		*trig;
470 	struct iio_poll_func		*pollfunc;
471 
472 	struct iio_chan_spec const	*channels;
473 	int				num_channels;
474 
475 	struct list_head		channel_attr_list;
476 	struct attribute_group		chan_attr_group;
477 	const char			*name;
478 	const struct iio_info		*info;
479 	struct mutex			info_exist_lock;
480 	const struct iio_buffer_setup_ops	*setup_ops;
481 	struct cdev			chrdev;
482 #define IIO_MAX_GROUPS 6
483 	const struct attribute_group	*groups[IIO_MAX_GROUPS + 1];
484 	int				groupcounter;
485 
486 	unsigned long			flags;
487 #if defined(CONFIG_DEBUG_FS)
488 	struct dentry			*debugfs_dentry;
489 	unsigned			cached_reg_addr;
490 #endif
491 };
492 
493 /**
494  * iio_find_channel_from_si() - get channel from its scan index
495  * @indio_dev:		device
496  * @si:			scan index to match
497  */
498 const struct iio_chan_spec
499 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
500 
501 /**
502  * iio_device_register() - register a device with the IIO subsystem
503  * @indio_dev:		Device structure filled by the device driver
504  **/
505 int iio_device_register(struct iio_dev *indio_dev);
506 
507 /**
508  * iio_device_unregister() - unregister a device from the IIO subsystem
509  * @indio_dev:		Device structure representing the device.
510  **/
511 void iio_device_unregister(struct iio_dev *indio_dev);
512 
513 /**
514  * iio_push_event() - try to add event to the list for userspace reading
515  * @indio_dev:		IIO device structure
516  * @ev_code:		What event
517  * @timestamp:		When the event occurred
518  **/
519 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
520 
521 extern struct bus_type iio_bus_type;
522 
523 /**
524  * iio_device_put() - reference counted deallocation of struct device
525  * @indio_dev: 		IIO device structure containing the device
526  **/
527 static inline void iio_device_put(struct iio_dev *indio_dev)
528 {
529 	if (indio_dev)
530 		put_device(&indio_dev->dev);
531 }
532 
533 /**
534  * dev_to_iio_dev() - Get IIO device struct from a device struct
535  * @dev: 		The device embedded in the IIO device
536  *
537  * Note: The device must be a IIO device, otherwise the result is undefined.
538  */
539 static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
540 {
541 	return container_of(dev, struct iio_dev, dev);
542 }
543 
544 /**
545  * iio_device_get() - increment reference count for the device
546  * @indio_dev: 		IIO device structure
547  *
548  * Returns: The passed IIO device
549  **/
550 static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
551 {
552 	return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
553 }
554 
555 
556 /**
557  * iio_device_set_drvdata() - Set device driver data
558  * @indio_dev: IIO device structure
559  * @data: Driver specific data
560  *
561  * Allows to attach an arbitrary pointer to an IIO device, which can later be
562  * retrieved by iio_device_get_drvdata().
563  */
564 static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
565 {
566 	dev_set_drvdata(&indio_dev->dev, data);
567 }
568 
569 /**
570  * iio_device_get_drvdata() - Get device driver data
571  * @indio_dev: IIO device structure
572  *
573  * Returns the data previously set with iio_device_set_drvdata()
574  */
575 static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev)
576 {
577 	return dev_get_drvdata(&indio_dev->dev);
578 }
579 
580 /* Can we make this smaller? */
581 #define IIO_ALIGN L1_CACHE_BYTES
582 /**
583  * iio_device_alloc() - allocate an iio_dev from a driver
584  * @sizeof_priv: 	Space to allocate for private structure.
585  **/
586 struct iio_dev *iio_device_alloc(int sizeof_priv);
587 
588 static inline void *iio_priv(const struct iio_dev *indio_dev)
589 {
590 	return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
591 }
592 
593 static inline struct iio_dev *iio_priv_to_dev(void *priv)
594 {
595 	return (struct iio_dev *)((char *)priv -
596 				  ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
597 }
598 
599 /**
600  * iio_device_free() - free an iio_dev from a driver
601  * @indio_dev: 		the iio_dev associated with the device
602  **/
603 void iio_device_free(struct iio_dev *indio_dev);
604 
605 /**
606  * devm_iio_device_alloc - Resource-managed iio_device_alloc()
607  * @dev: 		Device to allocate iio_dev for
608  * @sizeof_priv: 	Space to allocate for private structure.
609  *
610  * Managed iio_device_alloc.  iio_dev allocated with this function is
611  * automatically freed on driver detach.
612  *
613  * If an iio_dev allocated with this function needs to be freed separately,
614  * devm_iio_device_free() must be used.
615  *
616  * RETURNS:
617  * Pointer to allocated iio_dev on success, NULL on failure.
618  */
619 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv);
620 
621 /**
622  * devm_iio_device_free - Resource-managed iio_device_free()
623  * @dev:		Device this iio_dev belongs to
624  * @indio_dev: 		the iio_dev associated with the device
625  *
626  * Free iio_dev allocated with devm_iio_device_alloc().
627  */
628 void devm_iio_device_free(struct device *dev, struct iio_dev *indio_dev);
629 
630 /**
631  * devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc()
632  * @dev:		Device to allocate iio_trigger for
633  * @fmt:		trigger name format. If it includes format
634  *			specifiers, the additional arguments following
635  *			format are formatted and inserted in the resulting
636  *			string replacing their respective specifiers.
637  *
638  * Managed iio_trigger_alloc.  iio_trigger allocated with this function is
639  * automatically freed on driver detach.
640  *
641  * If an iio_trigger allocated with this function needs to be freed separately,
642  * devm_iio_trigger_free() must be used.
643  *
644  * RETURNS:
645  * Pointer to allocated iio_trigger on success, NULL on failure.
646  */
647 struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
648 						const char *fmt, ...);
649 
650 /**
651  * devm_iio_trigger_free - Resource-managed iio_trigger_free()
652  * @dev:		Device this iio_dev belongs to
653  * @iio_trig:		the iio_trigger associated with the device
654  *
655  * Free iio_trigger allocated with devm_iio_trigger_alloc().
656  */
657 void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig);
658 
659 /**
660  * iio_buffer_enabled() - helper function to test if the buffer is enabled
661  * @indio_dev:		IIO device structure for device
662  **/
663 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
664 {
665 	return indio_dev->currentmode
666 		& (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE);
667 }
668 
669 /**
670  * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
671  * @indio_dev:		IIO device structure for device
672  **/
673 #if defined(CONFIG_DEBUG_FS)
674 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
675 {
676 	return indio_dev->debugfs_dentry;
677 }
678 #else
679 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
680 {
681 	return NULL;
682 }
683 #endif
684 
685 int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
686 	int *fract);
687 
688 /**
689  * IIO_DEGREE_TO_RAD() - Convert degree to rad
690  * @deg: A value in degree
691  *
692  * Returns the given value converted from degree to rad
693  */
694 #define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
695 
696 /**
697  * IIO_G_TO_M_S_2() - Convert g to meter / second**2
698  * @g: A value in g
699  *
700  * Returns the given value converted from g to meter / second**2
701  */
702 #define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
703 
704 #endif /* _INDUSTRIAL_IO_H_ */
705