xref: /linux/include/linux/iio/iio.h (revision be709d48329a500621d2a05835283150ae137b45)
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_shared_by {
24 	IIO_SEPARATE,
25 	IIO_SHARED_BY_TYPE,
26 	IIO_SHARED_BY_DIR,
27 	IIO_SHARED_BY_ALL
28 };
29 
30 enum iio_endian {
31 	IIO_CPU,
32 	IIO_BE,
33 	IIO_LE,
34 };
35 
36 struct iio_chan_spec;
37 struct iio_dev;
38 
39 /**
40  * struct iio_chan_spec_ext_info - Extended channel info attribute
41  * @name:	Info attribute name
42  * @shared:	Whether this attribute is shared between all channels.
43  * @read:	Read callback for this info attribute, may be NULL.
44  * @write:	Write callback for this info attribute, may be NULL.
45  * @private:	Data private to the driver.
46  */
47 struct iio_chan_spec_ext_info {
48 	const char *name;
49 	enum iio_shared_by shared;
50 	ssize_t (*read)(struct iio_dev *, uintptr_t private,
51 			struct iio_chan_spec const *, char *buf);
52 	ssize_t (*write)(struct iio_dev *, uintptr_t private,
53 			 struct iio_chan_spec const *, const char *buf,
54 			 size_t len);
55 	uintptr_t private;
56 };
57 
58 /**
59  * struct iio_enum - Enum channel info attribute
60  * @items:	An array of strings.
61  * @num_items:	Length of the item array.
62  * @set:	Set callback function, may be NULL.
63  * @get:	Get callback function, may be NULL.
64  *
65  * The iio_enum struct can be used to implement enum style channel attributes.
66  * Enum style attributes are those which have a set of strings which map to
67  * unsigned integer values. The IIO enum helper code takes care of mapping
68  * between value and string as well as generating a "_available" file which
69  * contains a list of all available items. The set callback will be called when
70  * the attribute is updated. The last parameter is the index to the newly
71  * activated item. The get callback will be used to query the currently active
72  * item and is supposed to return the index for it.
73  */
74 struct iio_enum {
75 	const char * const *items;
76 	unsigned int num_items;
77 	int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
78 	int (*get)(struct iio_dev *, const struct iio_chan_spec *);
79 };
80 
81 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
82 	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
83 ssize_t iio_enum_read(struct iio_dev *indio_dev,
84 	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
85 ssize_t iio_enum_write(struct iio_dev *indio_dev,
86 	uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
87 	size_t len);
88 
89 /**
90  * IIO_ENUM() - Initialize enum extended channel attribute
91  * @_name:	Attribute name
92  * @_shared:	Whether the attribute is shared between all channels
93  * @_e:		Pointer to an iio_enum struct
94  *
95  * This should usually be used together with IIO_ENUM_AVAILABLE()
96  */
97 #define IIO_ENUM(_name, _shared, _e) \
98 { \
99 	.name = (_name), \
100 	.shared = (_shared), \
101 	.read = iio_enum_read, \
102 	.write = iio_enum_write, \
103 	.private = (uintptr_t)(_e), \
104 }
105 
106 /**
107  * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
108  * @_name:	Attribute name ("_available" will be appended to the name)
109  * @_e:		Pointer to an iio_enum struct
110  *
111  * Creates a read only attribute which lists all the available enum items in a
112  * space separated list. This should usually be used together with IIO_ENUM()
113  */
114 #define IIO_ENUM_AVAILABLE(_name, _e) \
115 { \
116 	.name = (_name "_available"), \
117 	.shared = IIO_SHARED_BY_TYPE, \
118 	.read = iio_enum_available_read, \
119 	.private = (uintptr_t)(_e), \
120 }
121 
122 /**
123  * struct iio_mount_matrix - iio mounting matrix
124  * @rotation: 3 dimensional space rotation matrix defining sensor alignment with
125  *            main hardware
126  */
127 struct iio_mount_matrix {
128 	const char *rotation[9];
129 };
130 
131 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
132 			      const struct iio_chan_spec *chan, char *buf);
133 int of_iio_read_mount_matrix(const struct device *dev, const char *propname,
134 			     struct iio_mount_matrix *matrix);
135 
136 typedef const struct iio_mount_matrix *
137 	(iio_get_mount_matrix_t)(const struct iio_dev *indio_dev,
138 				 const struct iio_chan_spec *chan);
139 
140 /**
141  * IIO_MOUNT_MATRIX() - Initialize mount matrix extended channel attribute
142  * @_shared:	Whether the attribute is shared between all channels
143  * @_get:	Pointer to an iio_get_mount_matrix_t accessor
144  */
145 #define IIO_MOUNT_MATRIX(_shared, _get) \
146 { \
147 	.name = "mount_matrix", \
148 	.shared = (_shared), \
149 	.read = iio_show_mount_matrix, \
150 	.private = (uintptr_t)(_get), \
151 }
152 
153 /**
154  * struct iio_event_spec - specification for a channel event
155  * @type:		    Type of the event
156  * @dir:		    Direction of the event
157  * @mask_separate:	    Bit mask of enum iio_event_info values. Attributes
158  *			    set in this mask will be registered per channel.
159  * @mask_shared_by_type:    Bit mask of enum iio_event_info values. Attributes
160  *			    set in this mask will be shared by channel type.
161  * @mask_shared_by_dir:	    Bit mask of enum iio_event_info values. Attributes
162  *			    set in this mask will be shared by channel type and
163  *			    direction.
164  * @mask_shared_by_all:	    Bit mask of enum iio_event_info values. Attributes
165  *			    set in this mask will be shared by all channels.
166  */
167 struct iio_event_spec {
168 	enum iio_event_type type;
169 	enum iio_event_direction dir;
170 	unsigned long mask_separate;
171 	unsigned long mask_shared_by_type;
172 	unsigned long mask_shared_by_dir;
173 	unsigned long mask_shared_by_all;
174 };
175 
176 /**
177  * struct iio_chan_spec - specification of a single channel
178  * @type:		What type of measurement is the channel making.
179  * @channel:		What number do we wish to assign the channel.
180  * @channel2:		If there is a second number for a differential
181  *			channel then this is it. If modified is set then the
182  *			value here specifies the modifier.
183  * @address:		Driver specific identifier.
184  * @scan_index:		Monotonic index to give ordering in scans when read
185  *			from a buffer.
186  * @scan_type:		struct describing the scan type
187  * @scan_type.sign:		's' or 'u' to specify signed or unsigned
188  * @scan_type.realbits:		Number of valid bits of data
189  * @scan_type.storagebits:	Realbits + padding
190  * @scan_type.shift:		Shift right by this before masking out
191  *				realbits.
192  * @scan_type.repeat:		Number of times real/storage bits repeats.
193  *				When the repeat element is more than 1, then
194  *				the type element in sysfs will show a repeat
195  *				value. Otherwise, the number of repetitions
196  *				is omitted.
197  * @scan_type.endianness:	little or big endian
198  * @info_mask_separate: What information is to be exported that is specific to
199  *			this channel.
200  * @info_mask_separate_available: What availability information is to be
201  *			exported that is specific to this channel.
202  * @info_mask_shared_by_type: What information is to be exported that is shared
203  *			by all channels of the same type.
204  * @info_mask_shared_by_type_available: What availability information is to be
205  *			exported that is shared by all channels of the same
206  *			type.
207  * @info_mask_shared_by_dir: What information is to be exported that is shared
208  *			by all channels of the same direction.
209  * @info_mask_shared_by_dir_available: What availability information is to be
210  *			exported that is shared by all channels of the same
211  *			direction.
212  * @info_mask_shared_by_all: What information is to be exported that is shared
213  *			by all channels.
214  * @info_mask_shared_by_all_available: What availability information is to be
215  *			exported that is shared by all channels.
216  * @event_spec:		Array of events which should be registered for this
217  *			channel.
218  * @num_event_specs:	Size of the event_spec array.
219  * @ext_info:		Array of extended info attributes for this channel.
220  *			The array is NULL terminated, the last element should
221  *			have its name field set to NULL.
222  * @extend_name:	Allows labeling of channel attributes with an
223  *			informative name. Note this has no effect codes etc,
224  *			unlike modifiers.
225  * @datasheet_name:	A name used in in-kernel mapping of channels. It should
226  *			correspond to the first name that the channel is referred
227  *			to by in the datasheet (e.g. IND), or the nearest
228  *			possible compound name (e.g. IND-INC).
229  * @modified:		Does a modifier apply to this channel. What these are
230  *			depends on the channel type.  Modifier is set in
231  *			channel2. Examples are IIO_MOD_X for axial sensors about
232  *			the 'x' axis.
233  * @indexed:		Specify the channel has a numerical index. If not,
234  *			the channel index number will be suppressed for sysfs
235  *			attributes but not for event codes.
236  * @output:		Channel is output.
237  * @differential:	Channel is differential.
238  */
239 struct iio_chan_spec {
240 	enum iio_chan_type	type;
241 	int			channel;
242 	int			channel2;
243 	unsigned long		address;
244 	int			scan_index;
245 	struct {
246 		char	sign;
247 		u8	realbits;
248 		u8	storagebits;
249 		u8	shift;
250 		u8	repeat;
251 		enum iio_endian endianness;
252 	} scan_type;
253 	long			info_mask_separate;
254 	long			info_mask_separate_available;
255 	long			info_mask_shared_by_type;
256 	long			info_mask_shared_by_type_available;
257 	long			info_mask_shared_by_dir;
258 	long			info_mask_shared_by_dir_available;
259 	long			info_mask_shared_by_all;
260 	long			info_mask_shared_by_all_available;
261 	const struct iio_event_spec *event_spec;
262 	unsigned int		num_event_specs;
263 	const struct iio_chan_spec_ext_info *ext_info;
264 	const char		*extend_name;
265 	const char		*datasheet_name;
266 	unsigned		modified:1;
267 	unsigned		indexed:1;
268 	unsigned		output:1;
269 	unsigned		differential:1;
270 };
271 
272 
273 /**
274  * iio_channel_has_info() - Checks whether a channel supports a info attribute
275  * @chan: The channel to be queried
276  * @type: Type of the info attribute to be checked
277  *
278  * Returns true if the channels supports reporting values for the given info
279  * attribute type, false otherwise.
280  */
281 static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
282 	enum iio_chan_info_enum type)
283 {
284 	return (chan->info_mask_separate & BIT(type)) |
285 		(chan->info_mask_shared_by_type & BIT(type)) |
286 		(chan->info_mask_shared_by_dir & BIT(type)) |
287 		(chan->info_mask_shared_by_all & BIT(type));
288 }
289 
290 /**
291  * iio_channel_has_available() - Checks if a channel has an available attribute
292  * @chan: The channel to be queried
293  * @type: Type of the available attribute to be checked
294  *
295  * Returns true if the channel supports reporting available values for the
296  * given attribute type, false otherwise.
297  */
298 static inline bool iio_channel_has_available(const struct iio_chan_spec *chan,
299 					     enum iio_chan_info_enum type)
300 {
301 	return (chan->info_mask_separate_available & BIT(type)) |
302 		(chan->info_mask_shared_by_type_available & BIT(type)) |
303 		(chan->info_mask_shared_by_dir_available & BIT(type)) |
304 		(chan->info_mask_shared_by_all_available & BIT(type));
305 }
306 
307 #define IIO_CHAN_SOFT_TIMESTAMP(_si) {					\
308 	.type = IIO_TIMESTAMP,						\
309 	.channel = -1,							\
310 	.scan_index = _si,						\
311 	.scan_type = {							\
312 		.sign = 's',						\
313 		.realbits = 64,					\
314 		.storagebits = 64,					\
315 		},							\
316 }
317 
318 s64 iio_get_time_ns(const struct iio_dev *indio_dev);
319 unsigned int iio_get_time_res(const struct iio_dev *indio_dev);
320 
321 /* Device operating modes */
322 #define INDIO_DIRECT_MODE		0x01
323 #define INDIO_BUFFER_TRIGGERED		0x02
324 #define INDIO_BUFFER_SOFTWARE		0x04
325 #define INDIO_BUFFER_HARDWARE		0x08
326 #define INDIO_EVENT_TRIGGERED		0x10
327 #define INDIO_HARDWARE_TRIGGERED	0x20
328 
329 #define INDIO_ALL_BUFFER_MODES					\
330 	(INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE | INDIO_BUFFER_SOFTWARE)
331 
332 #define INDIO_ALL_TRIGGERED_MODES	\
333 	(INDIO_BUFFER_TRIGGERED		\
334 	 | INDIO_EVENT_TRIGGERED	\
335 	 | INDIO_HARDWARE_TRIGGERED)
336 
337 #define INDIO_MAX_RAW_ELEMENTS		4
338 
339 struct iio_trigger; /* forward declaration */
340 
341 /**
342  * struct iio_info - constant information about device
343  * @event_attrs:	event control attributes
344  * @attrs:		general purpose device attributes
345  * @read_raw:		function to request a value from the device.
346  *			mask specifies which value. Note 0 means a reading of
347  *			the channel in question.  Return value will specify the
348  *			type of value returned by the device. val and val2 will
349  *			contain the elements making up the returned value.
350  * @read_raw_multi:	function to return values from the device.
351  *			mask specifies which value. Note 0 means a reading of
352  *			the channel in question.  Return value will specify the
353  *			type of value returned by the device. vals pointer
354  *			contain the elements making up the returned value.
355  *			max_len specifies maximum number of elements
356  *			vals pointer can contain. val_len is used to return
357  *			length of valid elements in vals.
358  * @read_avail:		function to return the available values from the device.
359  *			mask specifies which value. Note 0 means the available
360  *			values for the channel in question.  Return value
361  *			specifies if a IIO_AVAIL_LIST or a IIO_AVAIL_RANGE is
362  *			returned in vals. The type of the vals are returned in
363  *			type and the number of vals is returned in length. For
364  *			ranges, there are always three vals returned; min, step
365  *			and max. For lists, all possible values are enumerated.
366  * @write_raw:		function to write a value to the device.
367  *			Parameters are the same as for read_raw.
368  * @write_raw_get_fmt:	callback function to query the expected
369  *			format/precision. If not set by the driver, write_raw
370  *			returns IIO_VAL_INT_PLUS_MICRO.
371  * @read_event_config:	find out if the event is enabled.
372  * @write_event_config:	set if the event is enabled.
373  * @read_event_value:	read a configuration value associated with the event.
374  * @write_event_value:	write a configuration value for the event.
375  * @validate_trigger:	function to validate the trigger when the
376  *			current trigger gets changed.
377  * @update_scan_mode:	function to configure device and scan buffer when
378  *			channels have changed
379  * @debugfs_reg_access:	function to read or write register value of device
380  * @of_xlate:		function pointer to obtain channel specifier index.
381  *			When #iio-cells is greater than '0', the driver could
382  *			provide a custom of_xlate function that reads the
383  *			*args* and returns the appropriate index in registered
384  *			IIO channels array.
385  * @hwfifo_set_watermark: function pointer to set the current hardware
386  *			fifo watermark level; see hwfifo_* entries in
387  *			Documentation/ABI/testing/sysfs-bus-iio for details on
388  *			how the hardware fifo operates
389  * @hwfifo_flush_to_buffer: function pointer to flush the samples stored
390  *			in the hardware fifo to the device buffer. The driver
391  *			should not flush more than count samples. The function
392  *			must return the number of samples flushed, 0 if no
393  *			samples were flushed or a negative integer if no samples
394  *			were flushed and there was an error.
395  **/
396 struct iio_info {
397 	const struct attribute_group	*event_attrs;
398 	const struct attribute_group	*attrs;
399 
400 	int (*read_raw)(struct iio_dev *indio_dev,
401 			struct iio_chan_spec const *chan,
402 			int *val,
403 			int *val2,
404 			long mask);
405 
406 	int (*read_raw_multi)(struct iio_dev *indio_dev,
407 			struct iio_chan_spec const *chan,
408 			int max_len,
409 			int *vals,
410 			int *val_len,
411 			long mask);
412 
413 	int (*read_avail)(struct iio_dev *indio_dev,
414 			  struct iio_chan_spec const *chan,
415 			  const int **vals,
416 			  int *type,
417 			  int *length,
418 			  long mask);
419 
420 	int (*write_raw)(struct iio_dev *indio_dev,
421 			 struct iio_chan_spec const *chan,
422 			 int val,
423 			 int val2,
424 			 long mask);
425 
426 	int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
427 			 struct iio_chan_spec const *chan,
428 			 long mask);
429 
430 	int (*read_event_config)(struct iio_dev *indio_dev,
431 				 const struct iio_chan_spec *chan,
432 				 enum iio_event_type type,
433 				 enum iio_event_direction dir);
434 
435 	int (*write_event_config)(struct iio_dev *indio_dev,
436 				  const struct iio_chan_spec *chan,
437 				  enum iio_event_type type,
438 				  enum iio_event_direction dir,
439 				  int state);
440 
441 	int (*read_event_value)(struct iio_dev *indio_dev,
442 				const struct iio_chan_spec *chan,
443 				enum iio_event_type type,
444 				enum iio_event_direction dir,
445 				enum iio_event_info info, int *val, int *val2);
446 
447 	int (*write_event_value)(struct iio_dev *indio_dev,
448 				 const struct iio_chan_spec *chan,
449 				 enum iio_event_type type,
450 				 enum iio_event_direction dir,
451 				 enum iio_event_info info, int val, int val2);
452 
453 	int (*validate_trigger)(struct iio_dev *indio_dev,
454 				struct iio_trigger *trig);
455 	int (*update_scan_mode)(struct iio_dev *indio_dev,
456 				const unsigned long *scan_mask);
457 	int (*debugfs_reg_access)(struct iio_dev *indio_dev,
458 				  unsigned reg, unsigned writeval,
459 				  unsigned *readval);
460 	int (*of_xlate)(struct iio_dev *indio_dev,
461 			const struct of_phandle_args *iiospec);
462 	int (*hwfifo_set_watermark)(struct iio_dev *indio_dev, unsigned val);
463 	int (*hwfifo_flush_to_buffer)(struct iio_dev *indio_dev,
464 				      unsigned count);
465 };
466 
467 /**
468  * struct iio_buffer_setup_ops - buffer setup related callbacks
469  * @preenable:		[DRIVER] function to run prior to marking buffer enabled
470  * @postenable:		[DRIVER] function to run after marking buffer enabled
471  * @predisable:		[DRIVER] function to run prior to marking buffer
472  *			disabled
473  * @postdisable:	[DRIVER] function to run after marking buffer disabled
474  * @validate_scan_mask: [DRIVER] function callback to check whether a given
475  *			scan mask is valid for the device.
476  */
477 struct iio_buffer_setup_ops {
478 	int (*preenable)(struct iio_dev *);
479 	int (*postenable)(struct iio_dev *);
480 	int (*predisable)(struct iio_dev *);
481 	int (*postdisable)(struct iio_dev *);
482 	bool (*validate_scan_mask)(struct iio_dev *indio_dev,
483 				   const unsigned long *scan_mask);
484 };
485 
486 /**
487  * struct iio_dev - industrial I/O device
488  * @id:			[INTERN] used to identify device internally
489  * @driver_module:	[INTERN] used to make it harder to undercut users
490  * @modes:		[DRIVER] operating modes supported by device
491  * @currentmode:	[DRIVER] current operating mode
492  * @dev:		[DRIVER] device structure, should be assigned a parent
493  *			and owner
494  * @event_interface:	[INTERN] event chrdevs associated with interrupt lines
495  * @buffer:		[DRIVER] any buffer present
496  * @buffer_list:	[INTERN] list of all buffers currently attached
497  * @scan_bytes:		[INTERN] num bytes captured to be fed to buffer demux
498  * @mlock:		[DRIVER] lock used to prevent simultaneous device state
499  *			changes
500  * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
501  * @masklength:		[INTERN] the length of the mask established from
502  *			channels
503  * @active_scan_mask:	[INTERN] union of all scan masks requested by buffers
504  * @scan_timestamp:	[INTERN] set if any buffers have requested timestamp
505  * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
506  * @trig:		[INTERN] current device trigger (buffer modes)
507  * @trig_readonly:	[INTERN] mark the current trigger immutable
508  * @pollfunc:		[DRIVER] function run on trigger being received
509  * @pollfunc_event:	[DRIVER] function run on events trigger being received
510  * @channels:		[DRIVER] channel specification structure table
511  * @num_channels:	[DRIVER] number of channels specified in @channels.
512  * @channel_attr_list:	[INTERN] keep track of automatically created channel
513  *			attributes
514  * @chan_attr_group:	[INTERN] group for all attrs in base directory
515  * @name:		[DRIVER] name of the device.
516  * @info:		[DRIVER] callbacks and constant info from driver
517  * @clock_id:		[INTERN] timestamping clock posix identifier
518  * @info_exist_lock:	[INTERN] lock to prevent use during removal
519  * @setup_ops:		[DRIVER] callbacks to call before and after buffer
520  *			enable/disable
521  * @chrdev:		[INTERN] associated character device
522  * @groups:		[INTERN] attribute groups
523  * @groupcounter:	[INTERN] index of next attribute group
524  * @flags:		[INTERN] file ops related flags including busy flag.
525  * @debugfs_dentry:	[INTERN] device specific debugfs dentry.
526  * @cached_reg_addr:	[INTERN] cached register address for debugfs reads.
527  */
528 struct iio_dev {
529 	int				id;
530 	struct module			*driver_module;
531 
532 	int				modes;
533 	int				currentmode;
534 	struct device			dev;
535 
536 	struct iio_event_interface	*event_interface;
537 
538 	struct iio_buffer		*buffer;
539 	struct list_head		buffer_list;
540 	int				scan_bytes;
541 	struct mutex			mlock;
542 
543 	const unsigned long		*available_scan_masks;
544 	unsigned			masklength;
545 	const unsigned long		*active_scan_mask;
546 	bool				scan_timestamp;
547 	unsigned			scan_index_timestamp;
548 	struct iio_trigger		*trig;
549 	bool				trig_readonly;
550 	struct iio_poll_func		*pollfunc;
551 	struct iio_poll_func		*pollfunc_event;
552 
553 	struct iio_chan_spec const	*channels;
554 	int				num_channels;
555 
556 	struct list_head		channel_attr_list;
557 	struct attribute_group		chan_attr_group;
558 	const char			*name;
559 	const struct iio_info		*info;
560 	clockid_t			clock_id;
561 	struct mutex			info_exist_lock;
562 	const struct iio_buffer_setup_ops	*setup_ops;
563 	struct cdev			chrdev;
564 #define IIO_MAX_GROUPS 6
565 	const struct attribute_group	*groups[IIO_MAX_GROUPS + 1];
566 	int				groupcounter;
567 
568 	unsigned long			flags;
569 #if defined(CONFIG_DEBUG_FS)
570 	struct dentry			*debugfs_dentry;
571 	unsigned			cached_reg_addr;
572 #endif
573 };
574 
575 const struct iio_chan_spec
576 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
577 /**
578  * iio_device_register() - register a device with the IIO subsystem
579  * @indio_dev:		Device structure filled by the device driver
580  **/
581 #define iio_device_register(indio_dev) \
582 	__iio_device_register((indio_dev), THIS_MODULE)
583 int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod);
584 void iio_device_unregister(struct iio_dev *indio_dev);
585 /**
586  * devm_iio_device_register - Resource-managed iio_device_register()
587  * @dev:	Device to allocate iio_dev for
588  * @indio_dev:	Device structure filled by the device driver
589  *
590  * Managed iio_device_register.  The IIO device registered with this
591  * function is automatically unregistered on driver detach. This function
592  * calls iio_device_register() internally. Refer to that function for more
593  * information.
594  *
595  * If an iio_dev registered with this function needs to be unregistered
596  * separately, devm_iio_device_unregister() must be used.
597  *
598  * RETURNS:
599  * 0 on success, negative error number on failure.
600  */
601 #define devm_iio_device_register(dev, indio_dev) \
602 	__devm_iio_device_register((dev), (indio_dev), THIS_MODULE);
603 int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,
604 			       struct module *this_mod);
605 void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev);
606 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
607 int iio_device_claim_direct_mode(struct iio_dev *indio_dev);
608 void iio_device_release_direct_mode(struct iio_dev *indio_dev);
609 
610 extern struct bus_type iio_bus_type;
611 
612 /**
613  * iio_device_put() - reference counted deallocation of struct device
614  * @indio_dev: IIO device structure containing the device
615  **/
616 static inline void iio_device_put(struct iio_dev *indio_dev)
617 {
618 	if (indio_dev)
619 		put_device(&indio_dev->dev);
620 }
621 
622 /**
623  * iio_device_get_clock() - Retrieve current timestamping clock for the device
624  * @indio_dev: IIO device structure containing the device
625  */
626 static inline clockid_t iio_device_get_clock(const struct iio_dev *indio_dev)
627 {
628 	return indio_dev->clock_id;
629 }
630 
631 /**
632  * dev_to_iio_dev() - Get IIO device struct from a device struct
633  * @dev: 		The device embedded in the IIO device
634  *
635  * Note: The device must be a IIO device, otherwise the result is undefined.
636  */
637 static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
638 {
639 	return container_of(dev, struct iio_dev, dev);
640 }
641 
642 /**
643  * iio_device_get() - increment reference count for the device
644  * @indio_dev: 		IIO device structure
645  *
646  * Returns: The passed IIO device
647  **/
648 static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
649 {
650 	return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
651 }
652 
653 
654 /**
655  * iio_device_set_drvdata() - Set device driver data
656  * @indio_dev: IIO device structure
657  * @data: Driver specific data
658  *
659  * Allows to attach an arbitrary pointer to an IIO device, which can later be
660  * retrieved by iio_device_get_drvdata().
661  */
662 static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
663 {
664 	dev_set_drvdata(&indio_dev->dev, data);
665 }
666 
667 /**
668  * iio_device_get_drvdata() - Get device driver data
669  * @indio_dev: IIO device structure
670  *
671  * Returns the data previously set with iio_device_set_drvdata()
672  */
673 static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev)
674 {
675 	return dev_get_drvdata(&indio_dev->dev);
676 }
677 
678 /* Can we make this smaller? */
679 #define IIO_ALIGN L1_CACHE_BYTES
680 struct iio_dev *iio_device_alloc(int sizeof_priv);
681 
682 static inline void *iio_priv(const struct iio_dev *indio_dev)
683 {
684 	return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
685 }
686 
687 static inline struct iio_dev *iio_priv_to_dev(void *priv)
688 {
689 	return (struct iio_dev *)((char *)priv -
690 				  ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
691 }
692 
693 void iio_device_free(struct iio_dev *indio_dev);
694 int devm_iio_device_match(struct device *dev, void *res, void *data);
695 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv);
696 void devm_iio_device_free(struct device *dev, struct iio_dev *indio_dev);
697 struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
698 						const char *fmt, ...);
699 void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig);
700 
701 /**
702  * iio_buffer_enabled() - helper function to test if the buffer is enabled
703  * @indio_dev:		IIO device structure for device
704  **/
705 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
706 {
707 	return indio_dev->currentmode
708 		& (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE |
709 		   INDIO_BUFFER_SOFTWARE);
710 }
711 
712 /**
713  * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
714  * @indio_dev:		IIO device structure for device
715  **/
716 #if defined(CONFIG_DEBUG_FS)
717 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
718 {
719 	return indio_dev->debugfs_dentry;
720 }
721 #else
722 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
723 {
724 	return NULL;
725 }
726 #endif
727 
728 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals);
729 
730 int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
731 	int *fract);
732 
733 /**
734  * IIO_DEGREE_TO_RAD() - Convert degree to rad
735  * @deg: A value in degree
736  *
737  * Returns the given value converted from degree to rad
738  */
739 #define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
740 
741 /**
742  * IIO_RAD_TO_DEGREE() - Convert rad to degree
743  * @rad: A value in rad
744  *
745  * Returns the given value converted from rad to degree
746  */
747 #define IIO_RAD_TO_DEGREE(rad) \
748 	(((rad) * 18000000ULL + 314159ULL / 2) / 314159ULL)
749 
750 /**
751  * IIO_G_TO_M_S_2() - Convert g to meter / second**2
752  * @g: A value in g
753  *
754  * Returns the given value converted from g to meter / second**2
755  */
756 #define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
757 
758 /**
759  * IIO_M_S_2_TO_G() - Convert meter / second**2 to g
760  * @ms2: A value in meter / second**2
761  *
762  * Returns the given value converted from meter / second**2 to g
763  */
764 #define IIO_M_S_2_TO_G(ms2) (((ms2) * 100000ULL + 980665ULL / 2) / 980665ULL)
765 
766 #endif /* _INDUSTRIAL_IO_H_ */
767