1 /* SPDX-License-Identifier: GPL-2.0-only */
2 
3 /* The industrial I/O core
4  *
5  * Copyright (c) 2008 Jonathan Cameron
6  */
7 #ifndef _INDUSTRIAL_IO_H_
8 #define _INDUSTRIAL_IO_H_
9 
10 #include <linux/device.h>
11 #include <linux/cdev.h>
12 #include <linux/cleanup.h>
13 #include <linux/compiler_types.h>
14 #include <linux/slab.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 struct fwnode_reference_args;
23 
24 enum iio_shared_by {
25 	IIO_SEPARATE,
26 	IIO_SHARED_BY_TYPE,
27 	IIO_SHARED_BY_DIR,
28 	IIO_SHARED_BY_ALL
29 };
30 
31 enum iio_endian {
32 	IIO_CPU,
33 	IIO_BE,
34 	IIO_LE,
35 };
36 
37 struct iio_chan_spec;
38 struct iio_dev;
39 
40 /**
41  * struct iio_chan_spec_ext_info - Extended channel info attribute
42  * @name:	Info attribute name
43  * @shared:	Whether this attribute is shared between all channels.
44  * @read:	Read callback for this info attribute, may be NULL.
45  * @write:	Write callback for this info attribute, may be NULL.
46  * @private:	Data private to the driver.
47  */
48 struct iio_chan_spec_ext_info {
49 	const char *name;
50 	enum iio_shared_by shared;
51 	ssize_t (*read)(struct iio_dev *, uintptr_t private,
52 			struct iio_chan_spec const *, char *buf);
53 	ssize_t (*write)(struct iio_dev *, uintptr_t private,
54 			 struct iio_chan_spec const *, const char *buf,
55 			 size_t len);
56 	uintptr_t private;
57 };
58 
59 /**
60  * struct iio_enum - Enum channel info attribute
61  * @items:	An array of strings.
62  * @num_items:	Length of the item array.
63  * @set:	Set callback function, may be NULL.
64  * @get:	Get callback function, may be NULL.
65  *
66  * The iio_enum struct can be used to implement enum style channel attributes.
67  * Enum style attributes are those which have a set of strings which map to
68  * unsigned integer values. The IIO enum helper code takes care of mapping
69  * between value and string as well as generating a "_available" file which
70  * contains a list of all available items. The set callback will be called when
71  * the attribute is updated. The last parameter is the index to the newly
72  * activated item. The get callback will be used to query the currently active
73  * item and is supposed to return the index for it.
74  */
75 struct iio_enum {
76 	const char * const *items;
77 	unsigned int num_items;
78 	int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
79 	int (*get)(struct iio_dev *, const struct iio_chan_spec *);
80 };
81 
82 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
83 	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
84 ssize_t iio_enum_read(struct iio_dev *indio_dev,
85 	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
86 ssize_t iio_enum_write(struct iio_dev *indio_dev,
87 	uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
88 	size_t len);
89 
90 /**
91  * IIO_ENUM() - Initialize enum extended channel attribute
92  * @_name:	Attribute name
93  * @_shared:	Whether the attribute is shared between all channels
94  * @_e:		Pointer to an iio_enum struct
95  *
96  * This should usually be used together with IIO_ENUM_AVAILABLE()
97  */
98 #define IIO_ENUM(_name, _shared, _e) \
99 { \
100 	.name = (_name), \
101 	.shared = (_shared), \
102 	.read = iio_enum_read, \
103 	.write = iio_enum_write, \
104 	.private = (uintptr_t)(_e), \
105 }
106 
107 /**
108  * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
109  * @_name:	Attribute name ("_available" will be appended to the name)
110  * @_shared:	Whether the attribute is shared between all channels
111  * @_e:		Pointer to an iio_enum struct
112  *
113  * Creates a read only attribute which lists all the available enum items in a
114  * space separated list. This should usually be used together with IIO_ENUM()
115  */
116 #define IIO_ENUM_AVAILABLE(_name, _shared, _e) \
117 { \
118 	.name = (_name "_available"), \
119 	.shared = _shared, \
120 	.read = iio_enum_available_read, \
121 	.private = (uintptr_t)(_e), \
122 }
123 
124 /**
125  * struct iio_mount_matrix - iio mounting matrix
126  * @rotation: 3 dimensional space rotation matrix defining sensor alignment with
127  *            main hardware
128  */
129 struct iio_mount_matrix {
130 	const char *rotation[9];
131 };
132 
133 ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv,
134 			      const struct iio_chan_spec *chan, char *buf);
135 int iio_read_mount_matrix(struct device *dev, struct iio_mount_matrix *matrix);
136 
137 typedef const struct iio_mount_matrix *
138 	(iio_get_mount_matrix_t)(const struct iio_dev *indio_dev,
139 				 const struct iio_chan_spec *chan);
140 
141 /**
142  * IIO_MOUNT_MATRIX() - Initialize mount matrix extended channel attribute
143  * @_shared:	Whether the attribute is shared between all channels
144  * @_get:	Pointer to an iio_get_mount_matrix_t accessor
145  */
146 #define IIO_MOUNT_MATRIX(_shared, _get) \
147 { \
148 	.name = "mount_matrix", \
149 	.shared = (_shared), \
150 	.read = iio_show_mount_matrix, \
151 	.private = (uintptr_t)(_get), \
152 }
153 
154 /**
155  * struct iio_event_spec - specification for a channel event
156  * @type:		    Type of the event
157  * @dir:		    Direction of the event
158  * @mask_separate:	    Bit mask of enum iio_event_info values. Attributes
159  *			    set in this mask will be registered per channel.
160  * @mask_shared_by_type:    Bit mask of enum iio_event_info values. Attributes
161  *			    set in this mask will be shared by channel type.
162  * @mask_shared_by_dir:	    Bit mask of enum iio_event_info values. Attributes
163  *			    set in this mask will be shared by channel type and
164  *			    direction.
165  * @mask_shared_by_all:	    Bit mask of enum iio_event_info values. Attributes
166  *			    set in this mask will be shared by all channels.
167  */
168 struct iio_event_spec {
169 	enum iio_event_type type;
170 	enum iio_event_direction dir;
171 	unsigned long mask_separate;
172 	unsigned long mask_shared_by_type;
173 	unsigned long mask_shared_by_dir;
174 	unsigned long mask_shared_by_all;
175 };
176 
177 /**
178  * struct iio_scan_type - specification for channel data format in buffer
179  * @sign:		's' or 'u' to specify signed or unsigned
180  * @realbits:		Number of valid bits of data
181  * @storagebits:	Realbits + padding
182  * @shift:		Shift right by this before masking out realbits.
183  * @repeat:		Number of times real/storage bits repeats. When the
184  *			repeat element is more than 1, then the type element in
185  *			sysfs will show a repeat value. Otherwise, the number
186  *			of repetitions is omitted.
187  * @endianness:		little or big endian
188  */
189 struct iio_scan_type {
190 	char	sign;
191 	u8	realbits;
192 	u8	storagebits;
193 	u8	shift;
194 	u8	repeat;
195 	enum iio_endian endianness;
196 };
197 
198 /**
199  * struct iio_chan_spec - specification of a single channel
200  * @type:		What type of measurement is the channel making.
201  * @channel:		What number do we wish to assign the channel.
202  * @channel2:		If there is a second number for a differential
203  *			channel then this is it. If modified is set then the
204  *			value here specifies the modifier.
205  * @address:		Driver specific identifier.
206  * @scan_index:		Monotonic index to give ordering in scans when read
207  *			from a buffer.
208  * @scan_type:		struct describing the scan type - mutually exclusive
209  *			with ext_scan_type.
210  * @ext_scan_type:	Used in rare cases where there is more than one scan
211  *			format for a channel. When this is used, the flag
212  *			has_ext_scan_type must be set and the driver must
213  *			implement get_current_scan_type in struct iio_info.
214  * @num_ext_scan_type:	Number of elements in ext_scan_type.
215  * @info_mask_separate: What information is to be exported that is specific to
216  *			this channel.
217  * @info_mask_separate_available: What availability information is to be
218  *			exported that is specific to this channel.
219  * @info_mask_shared_by_type: What information is to be exported that is shared
220  *			by all channels of the same type.
221  * @info_mask_shared_by_type_available: What availability information is to be
222  *			exported that is shared by all channels of the same
223  *			type.
224  * @info_mask_shared_by_dir: What information is to be exported that is shared
225  *			by all channels of the same direction.
226  * @info_mask_shared_by_dir_available: What availability information is to be
227  *			exported that is shared by all channels of the same
228  *			direction.
229  * @info_mask_shared_by_all: What information is to be exported that is shared
230  *			by all channels.
231  * @info_mask_shared_by_all_available: What availability information is to be
232  *			exported that is shared by all channels.
233  * @event_spec:		Array of events which should be registered for this
234  *			channel.
235  * @num_event_specs:	Size of the event_spec array.
236  * @ext_info:		Array of extended info attributes for this channel.
237  *			The array is NULL terminated, the last element should
238  *			have its name field set to NULL.
239  * @extend_name:	Allows labeling of channel attributes with an
240  *			informative name. Note this has no effect codes etc,
241  *			unlike modifiers.
242  *			This field is deprecated in favour of providing
243  *			iio_info->read_label() to override the label, which
244  *			unlike @extend_name does not affect sysfs filenames.
245  * @datasheet_name:	A name used in in-kernel mapping of channels. It should
246  *			correspond to the first name that the channel is referred
247  *			to by in the datasheet (e.g. IND), or the nearest
248  *			possible compound name (e.g. IND-INC).
249  * @modified:		Does a modifier apply to this channel. What these are
250  *			depends on the channel type.  Modifier is set in
251  *			channel2. Examples are IIO_MOD_X for axial sensors about
252  *			the 'x' axis.
253  * @indexed:		Specify the channel has a numerical index. If not,
254  *			the channel index number will be suppressed for sysfs
255  *			attributes but not for event codes.
256  * @output:		Channel is output.
257  * @differential:	Channel is differential.
258  * @has_ext_scan_type:	True if ext_scan_type is used instead of scan_type.
259  */
260 struct iio_chan_spec {
261 	enum iio_chan_type	type;
262 	int			channel;
263 	int			channel2;
264 	unsigned long		address;
265 	int			scan_index;
266 	union {
267 		struct iio_scan_type scan_type;
268 		struct {
269 			const struct iio_scan_type *ext_scan_type;
270 			unsigned int num_ext_scan_type;
271 		};
272 	};
273 	long			info_mask_separate;
274 	long			info_mask_separate_available;
275 	long			info_mask_shared_by_type;
276 	long			info_mask_shared_by_type_available;
277 	long			info_mask_shared_by_dir;
278 	long			info_mask_shared_by_dir_available;
279 	long			info_mask_shared_by_all;
280 	long			info_mask_shared_by_all_available;
281 	const struct iio_event_spec *event_spec;
282 	unsigned int		num_event_specs;
283 	const struct iio_chan_spec_ext_info *ext_info;
284 	const char		*extend_name;
285 	const char		*datasheet_name;
286 	unsigned int		modified:1;
287 	unsigned int		indexed:1;
288 	unsigned int		output:1;
289 	unsigned int		differential:1;
290 	unsigned int		has_ext_scan_type:1;
291 };
292 
293 
294 /**
295  * iio_channel_has_info() - Checks whether a channel supports a info attribute
296  * @chan: The channel to be queried
297  * @type: Type of the info attribute to be checked
298  *
299  * Returns true if the channels supports reporting values for the given info
300  * attribute type, false otherwise.
301  */
iio_channel_has_info(const struct iio_chan_spec * chan,enum iio_chan_info_enum type)302 static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
303 	enum iio_chan_info_enum type)
304 {
305 	return (chan->info_mask_separate & BIT(type)) |
306 		(chan->info_mask_shared_by_type & BIT(type)) |
307 		(chan->info_mask_shared_by_dir & BIT(type)) |
308 		(chan->info_mask_shared_by_all & BIT(type));
309 }
310 
311 /**
312  * iio_channel_has_available() - Checks if a channel has an available attribute
313  * @chan: The channel to be queried
314  * @type: Type of the available attribute to be checked
315  *
316  * Returns true if the channel supports reporting available values for the
317  * given attribute type, false otherwise.
318  */
iio_channel_has_available(const struct iio_chan_spec * chan,enum iio_chan_info_enum type)319 static inline bool iio_channel_has_available(const struct iio_chan_spec *chan,
320 					     enum iio_chan_info_enum type)
321 {
322 	return (chan->info_mask_separate_available & BIT(type)) |
323 		(chan->info_mask_shared_by_type_available & BIT(type)) |
324 		(chan->info_mask_shared_by_dir_available & BIT(type)) |
325 		(chan->info_mask_shared_by_all_available & BIT(type));
326 }
327 
328 #define IIO_CHAN_SOFT_TIMESTAMP(_si) {					\
329 	.type = IIO_TIMESTAMP,						\
330 	.channel = -1,							\
331 	.scan_index = _si,						\
332 	.scan_type = {							\
333 		.sign = 's',						\
334 		.realbits = 64,					\
335 		.storagebits = 64,					\
336 		},							\
337 }
338 
339 s64 iio_get_time_ns(const struct iio_dev *indio_dev);
340 
341 /*
342  * Device operating modes
343  * @INDIO_DIRECT_MODE: There is an access to either:
344  * a) The last single value available for devices that do not provide
345  *    on-demand reads.
346  * b) A new value after performing an on-demand read otherwise.
347  * On most devices, this is a single-shot read. On some devices with data
348  * streams without an 'on-demand' function, this might also be the 'last value'
349  * feature. Above all, this mode internally means that we are not in any of the
350  * other modes, and sysfs reads should work.
351  * Device drivers should inform the core if they support this mode.
352  * @INDIO_BUFFER_TRIGGERED: Common mode when dealing with kfifo buffers.
353  * It indicates that an explicit trigger is required. This requests the core to
354  * attach a poll function when enabling the buffer, which is indicated by the
355  * _TRIGGERED suffix.
356  * The core will ensure this mode is set when registering a triggered buffer
357  * with iio_triggered_buffer_setup().
358  * @INDIO_BUFFER_SOFTWARE: Another kfifo buffer mode, but not event triggered.
359  * No poll function can be attached because there is no triggered infrastructure
360  * we can use to cause capture. There is a kfifo that the driver will fill, but
361  * not "only one scan at a time". Typically, hardware will have a buffer that
362  * can hold multiple scans. Software may read one or more scans at a single time
363  * and push the available data to a Kfifo. This means the core will not attach
364  * any poll function when enabling the buffer.
365  * The core will ensure this mode is set when registering a simple kfifo buffer
366  * with devm_iio_kfifo_buffer_setup().
367  * @INDIO_BUFFER_HARDWARE: For specific hardware, if unsure do not use this mode.
368  * Same as above but this time the buffer is not a kfifo where we have direct
369  * access to the data. Instead, the consumer driver must access the data through
370  * non software visible channels (or DMA when there is no demux possible in
371  * software)
372  * The core will ensure this mode is set when registering a dmaengine buffer
373  * with devm_iio_dmaengine_buffer_setup().
374  * @INDIO_EVENT_TRIGGERED: Very unusual mode.
375  * Triggers usually refer to an external event which will start data capture.
376  * Here it is kind of the opposite as, a particular state of the data might
377  * produce an event which can be considered as an event. We don't necessarily
378  * have access to the data itself, but to the event produced. For example, this
379  * can be a threshold detector. The internal path of this mode is very close to
380  * the INDIO_BUFFER_TRIGGERED mode.
381  * The core will ensure this mode is set when registering a triggered event.
382  * @INDIO_HARDWARE_TRIGGERED: Very unusual mode.
383  * Here, triggers can result in data capture and can be routed to multiple
384  * hardware components, which make them close to regular triggers in the way
385  * they must be managed by the core, but without the entire interrupts/poll
386  * functions burden. Interrupts are irrelevant as the data flow is hardware
387  * mediated and distributed.
388  */
389 #define INDIO_DIRECT_MODE		0x01
390 #define INDIO_BUFFER_TRIGGERED		0x02
391 #define INDIO_BUFFER_SOFTWARE		0x04
392 #define INDIO_BUFFER_HARDWARE		0x08
393 #define INDIO_EVENT_TRIGGERED		0x10
394 #define INDIO_HARDWARE_TRIGGERED	0x20
395 
396 #define INDIO_ALL_BUFFER_MODES					\
397 	(INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE | INDIO_BUFFER_SOFTWARE)
398 
399 #define INDIO_ALL_TRIGGERED_MODES	\
400 	(INDIO_BUFFER_TRIGGERED		\
401 	 | INDIO_EVENT_TRIGGERED	\
402 	 | INDIO_HARDWARE_TRIGGERED)
403 
404 #define INDIO_MAX_RAW_ELEMENTS		4
405 
406 struct iio_val_int_plus_micro {
407 	int integer;
408 	int micro;
409 };
410 
411 struct iio_trigger; /* forward declaration */
412 
413 /**
414  * struct iio_info - constant information about device
415  * @event_attrs:	event control attributes
416  * @attrs:		general purpose device attributes
417  * @read_raw:		function to request a value from the device.
418  *			mask specifies which value. Note 0 means a reading of
419  *			the channel in question.  Return value will specify the
420  *			type of value returned by the device. val and val2 will
421  *			contain the elements making up the returned value.
422  * @read_raw_multi:	function to return values from the device.
423  *			mask specifies which value. Note 0 means a reading of
424  *			the channel in question.  Return value will specify the
425  *			type of value returned by the device. vals pointer
426  *			contain the elements making up the returned value.
427  *			max_len specifies maximum number of elements
428  *			vals pointer can contain. val_len is used to return
429  *			length of valid elements in vals.
430  * @read_avail:		function to return the available values from the device.
431  *			mask specifies which value. Note 0 means the available
432  *			values for the channel in question.  Return value
433  *			specifies if a IIO_AVAIL_LIST or a IIO_AVAIL_RANGE is
434  *			returned in vals. The type of the vals are returned in
435  *			type and the number of vals is returned in length. For
436  *			ranges, there are always three vals returned; min, step
437  *			and max. For lists, all possible values are enumerated.
438  * @write_raw:		function to write a value to the device.
439  *			Parameters are the same as for read_raw.
440  * @read_label:		function to request label name for a specified label,
441  *			for better channel identification.
442  * @write_raw_get_fmt:	callback function to query the expected
443  *			format/precision. If not set by the driver, write_raw
444  *			returns IIO_VAL_INT_PLUS_MICRO.
445  * @read_event_config:	find out if the event is enabled.
446  * @write_event_config:	set if the event is enabled.
447  * @read_event_value:	read a configuration value associated with the event.
448  * @write_event_value:	write a configuration value for the event.
449  * @read_event_label:	function to request label name for a specified label,
450  *			for better event identification.
451  * @validate_trigger:	function to validate the trigger when the
452  *			current trigger gets changed.
453  * @get_current_scan_type: must be implemented by drivers that use ext_scan_type
454  *			in the channel spec to return the index of the currently
455  *			active ext_scan type for a channel.
456  * @update_scan_mode:	function to configure device and scan buffer when
457  *			channels have changed
458  * @debugfs_reg_access:	function to read or write register value of device
459  * @fwnode_xlate:	fwnode based function pointer to obtain channel specifier index.
460  * @hwfifo_set_watermark: function pointer to set the current hardware
461  *			fifo watermark level; see hwfifo_* entries in
462  *			Documentation/ABI/testing/sysfs-bus-iio for details on
463  *			how the hardware fifo operates
464  * @hwfifo_flush_to_buffer: function pointer to flush the samples stored
465  *			in the hardware fifo to the device buffer. The driver
466  *			should not flush more than count samples. The function
467  *			must return the number of samples flushed, 0 if no
468  *			samples were flushed or a negative integer if no samples
469  *			were flushed and there was an error.
470  **/
471 struct iio_info {
472 	const struct attribute_group	*event_attrs;
473 	const struct attribute_group	*attrs;
474 
475 	int (*read_raw)(struct iio_dev *indio_dev,
476 			struct iio_chan_spec const *chan,
477 			int *val,
478 			int *val2,
479 			long mask);
480 
481 	int (*read_raw_multi)(struct iio_dev *indio_dev,
482 			struct iio_chan_spec const *chan,
483 			int max_len,
484 			int *vals,
485 			int *val_len,
486 			long mask);
487 
488 	int (*read_avail)(struct iio_dev *indio_dev,
489 			  struct iio_chan_spec const *chan,
490 			  const int **vals,
491 			  int *type,
492 			  int *length,
493 			  long mask);
494 
495 	int (*write_raw)(struct iio_dev *indio_dev,
496 			 struct iio_chan_spec const *chan,
497 			 int val,
498 			 int val2,
499 			 long mask);
500 
501 	int (*read_label)(struct iio_dev *indio_dev,
502 			 struct iio_chan_spec const *chan,
503 			 char *label);
504 
505 	int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
506 			 struct iio_chan_spec const *chan,
507 			 long mask);
508 
509 	int (*read_event_config)(struct iio_dev *indio_dev,
510 				 const struct iio_chan_spec *chan,
511 				 enum iio_event_type type,
512 				 enum iio_event_direction dir);
513 
514 	int (*write_event_config)(struct iio_dev *indio_dev,
515 				  const struct iio_chan_spec *chan,
516 				  enum iio_event_type type,
517 				  enum iio_event_direction dir,
518 				  bool state);
519 
520 	int (*read_event_value)(struct iio_dev *indio_dev,
521 				const struct iio_chan_spec *chan,
522 				enum iio_event_type type,
523 				enum iio_event_direction dir,
524 				enum iio_event_info info, int *val, int *val2);
525 
526 	int (*write_event_value)(struct iio_dev *indio_dev,
527 				 const struct iio_chan_spec *chan,
528 				 enum iio_event_type type,
529 				 enum iio_event_direction dir,
530 				 enum iio_event_info info, int val, int val2);
531 
532 	int (*read_event_label)(struct iio_dev *indio_dev,
533 				struct iio_chan_spec const *chan,
534 				enum iio_event_type type,
535 				enum iio_event_direction dir,
536 				char *label);
537 
538 	int (*validate_trigger)(struct iio_dev *indio_dev,
539 				struct iio_trigger *trig);
540 	int (*get_current_scan_type)(const struct iio_dev *indio_dev,
541 				     const struct iio_chan_spec *chan);
542 	int (*update_scan_mode)(struct iio_dev *indio_dev,
543 				const unsigned long *scan_mask);
544 	int (*debugfs_reg_access)(struct iio_dev *indio_dev,
545 				  unsigned int reg, unsigned int writeval,
546 				  unsigned int *readval);
547 	int (*fwnode_xlate)(struct iio_dev *indio_dev,
548 			    const struct fwnode_reference_args *iiospec);
549 	int (*hwfifo_set_watermark)(struct iio_dev *indio_dev, unsigned int val);
550 	int (*hwfifo_flush_to_buffer)(struct iio_dev *indio_dev,
551 				      unsigned int count);
552 };
553 
554 /**
555  * struct iio_buffer_setup_ops - buffer setup related callbacks
556  * @preenable:		[DRIVER] function to run prior to marking buffer enabled
557  * @postenable:		[DRIVER] function to run after marking buffer enabled
558  * @predisable:		[DRIVER] function to run prior to marking buffer
559  *			disabled
560  * @postdisable:	[DRIVER] function to run after marking buffer disabled
561  * @validate_scan_mask: [DRIVER] function callback to check whether a given
562  *			scan mask is valid for the device.
563  */
564 struct iio_buffer_setup_ops {
565 	int (*preenable)(struct iio_dev *);
566 	int (*postenable)(struct iio_dev *);
567 	int (*predisable)(struct iio_dev *);
568 	int (*postdisable)(struct iio_dev *);
569 	bool (*validate_scan_mask)(struct iio_dev *indio_dev,
570 				   const unsigned long *scan_mask);
571 };
572 
573 /**
574  * struct iio_dev - industrial I/O device
575  * @modes:		[DRIVER] bitmask listing all the operating modes
576  *			supported by the IIO device. This list should be
577  *			initialized before registering the IIO device. It can
578  *			also be filed up by the IIO core, as a result of
579  *			enabling particular features in the driver
580  *			(see iio_triggered_event_setup()).
581  * @dev:		[DRIVER] device structure, should be assigned a parent
582  *			and owner
583  * @buffer:		[DRIVER] any buffer present
584  * @scan_bytes:		[INTERN] num bytes captured to be fed to buffer demux
585  * @available_scan_masks: [DRIVER] optional array of allowed bitmasks. Sort the
586  *			   array in order of preference, the most preferred
587  *			   masks first.
588  * @masklength:		[INTERN] the length of the mask established from
589  *			channels
590  * @active_scan_mask:	[INTERN] union of all scan masks requested by buffers
591  * @scan_timestamp:	[INTERN] set if any buffers have requested timestamp
592  * @trig:		[INTERN] current device trigger (buffer modes)
593  * @pollfunc:		[DRIVER] function run on trigger being received
594  * @pollfunc_event:	[DRIVER] function run on events trigger being received
595  * @channels:		[DRIVER] channel specification structure table
596  * @num_channels:	[DRIVER] number of channels specified in @channels.
597  * @name:		[DRIVER] name of the device.
598  * @label:              [DRIVER] unique name to identify which device this is
599  * @info:		[DRIVER] callbacks and constant info from driver
600  * @setup_ops:		[DRIVER] callbacks to call before and after buffer
601  *			enable/disable
602  * @priv:		[DRIVER] reference to driver's private information
603  *			**MUST** be accessed **ONLY** via iio_priv() helper
604  */
605 struct iio_dev {
606 	int				modes;
607 	struct device			dev;
608 
609 	struct iio_buffer		*buffer;
610 	int				scan_bytes;
611 
612 	const unsigned long		*available_scan_masks;
613 	unsigned int			__private masklength;
614 	const unsigned long		*active_scan_mask;
615 	bool				__private scan_timestamp;
616 	struct iio_trigger		*trig;
617 	struct iio_poll_func		*pollfunc;
618 	struct iio_poll_func		*pollfunc_event;
619 
620 	struct iio_chan_spec const	*channels;
621 	int				num_channels;
622 
623 	const char			*name;
624 	const char			*label;
625 	const struct iio_info		*info;
626 	const struct iio_buffer_setup_ops	*setup_ops;
627 
628 	void				*__private priv;
629 };
630 
631 int iio_device_id(struct iio_dev *indio_dev);
632 int iio_device_get_current_mode(struct iio_dev *indio_dev);
633 bool iio_buffer_enabled(struct iio_dev *indio_dev);
634 
635 const struct iio_chan_spec
636 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
637 /**
638  * iio_device_register() - register a device with the IIO subsystem
639  * @indio_dev:		Device structure filled by the device driver
640  **/
641 #define iio_device_register(indio_dev) \
642 	__iio_device_register((indio_dev), THIS_MODULE)
643 int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod);
644 void iio_device_unregister(struct iio_dev *indio_dev);
645 /**
646  * devm_iio_device_register - Resource-managed iio_device_register()
647  * @dev:	Device to allocate iio_dev for
648  * @indio_dev:	Device structure filled by the device driver
649  *
650  * Managed iio_device_register.  The IIO device registered with this
651  * function is automatically unregistered on driver detach. This function
652  * calls iio_device_register() internally. Refer to that function for more
653  * information.
654  *
655  * RETURNS:
656  * 0 on success, negative error number on failure.
657  */
658 #define devm_iio_device_register(dev, indio_dev) \
659 	__devm_iio_device_register((dev), (indio_dev), THIS_MODULE)
660 int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,
661 			       struct module *this_mod);
662 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
663 int iio_device_claim_direct_mode(struct iio_dev *indio_dev);
664 void iio_device_release_direct_mode(struct iio_dev *indio_dev);
665 
666 /*
667  * Helper functions that allow claim and release of direct mode
668  * in a fashion that doesn't generate many false positives from sparse.
669  * Note this must remain static inline in the header so that sparse
670  * can see the __acquire() marking. Revisit when sparse supports
671  * __cond_acquires()
672  */
iio_device_claim_direct(struct iio_dev * indio_dev)673 static inline bool iio_device_claim_direct(struct iio_dev *indio_dev)
674 {
675 	int ret = iio_device_claim_direct_mode(indio_dev);
676 
677 	if (ret)
678 		return false;
679 
680 	__acquire(iio_dev);
681 
682 	return true;
683 }
684 
iio_device_release_direct(struct iio_dev * indio_dev)685 static inline void iio_device_release_direct(struct iio_dev *indio_dev)
686 {
687 	iio_device_release_direct_mode(indio_dev);
688 	__release(indio_dev);
689 }
690 
691 /*
692  * This autocleanup logic is normally used via
693  * iio_device_claim_direct_scoped().
694  */
695 DEFINE_GUARD(iio_claim_direct, struct iio_dev *, iio_device_claim_direct_mode(_T),
696 	     iio_device_release_direct_mode(_T))
697 
698 DEFINE_GUARD_COND(iio_claim_direct, _try, ({
699 			struct iio_dev *dev;
700 			int d = iio_device_claim_direct_mode(_T);
701 
702 			if (d < 0)
703 				dev = NULL;
704 			else
705 				dev = _T;
706 			dev;
707 		}))
708 
709 /**
710  * iio_device_claim_direct_scoped() - Scoped call to iio_device_claim_direct.
711  * @fail: What to do on failure to claim device.
712  * @iio_dev: Pointer to the IIO devices structure
713  */
714 #define iio_device_claim_direct_scoped(fail, iio_dev) \
715 	scoped_cond_guard(iio_claim_direct_try, fail, iio_dev)
716 
717 int iio_device_claim_buffer_mode(struct iio_dev *indio_dev);
718 void iio_device_release_buffer_mode(struct iio_dev *indio_dev);
719 
720 extern const struct bus_type iio_bus_type;
721 
722 /**
723  * iio_device_put() - reference counted deallocation of struct device
724  * @indio_dev: IIO device structure containing the device
725  **/
iio_device_put(struct iio_dev * indio_dev)726 static inline void iio_device_put(struct iio_dev *indio_dev)
727 {
728 	if (indio_dev)
729 		put_device(&indio_dev->dev);
730 }
731 
732 clockid_t iio_device_get_clock(const struct iio_dev *indio_dev);
733 int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id);
734 
735 /**
736  * dev_to_iio_dev() - Get IIO device struct from a device struct
737  * @dev: 		The device embedded in the IIO device
738  *
739  * Note: The device must be a IIO device, otherwise the result is undefined.
740  */
dev_to_iio_dev(struct device * dev)741 static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
742 {
743 	return container_of(dev, struct iio_dev, dev);
744 }
745 
746 /**
747  * iio_device_get() - increment reference count for the device
748  * @indio_dev: 		IIO device structure
749  *
750  * Returns: The passed IIO device
751  **/
iio_device_get(struct iio_dev * indio_dev)752 static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
753 {
754 	return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
755 }
756 
757 /**
758  * iio_device_set_parent() - assign parent device to the IIO device object
759  * @indio_dev: 		IIO device structure
760  * @parent:		reference to parent device object
761  *
762  * This utility must be called between IIO device allocation
763  * (via devm_iio_device_alloc()) & IIO device registration
764  * (via iio_device_register() and devm_iio_device_register())).
765  * By default, the device allocation will also assign a parent device to
766  * the IIO device object. In cases where devm_iio_device_alloc() is used,
767  * sometimes the parent device must be different than the device used to
768  * manage the allocation.
769  * In that case, this helper should be used to change the parent, hence the
770  * requirement to call this between allocation & registration.
771  **/
iio_device_set_parent(struct iio_dev * indio_dev,struct device * parent)772 static inline void iio_device_set_parent(struct iio_dev *indio_dev,
773 					 struct device *parent)
774 {
775 	indio_dev->dev.parent = parent;
776 }
777 
778 /**
779  * iio_device_set_drvdata() - Set device driver data
780  * @indio_dev: IIO device structure
781  * @data: Driver specific data
782  *
783  * Allows to attach an arbitrary pointer to an IIO device, which can later be
784  * retrieved by iio_device_get_drvdata().
785  */
iio_device_set_drvdata(struct iio_dev * indio_dev,void * data)786 static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
787 {
788 	dev_set_drvdata(&indio_dev->dev, data);
789 }
790 
791 /**
792  * iio_device_get_drvdata() - Get device driver data
793  * @indio_dev: IIO device structure
794  *
795  * Returns the data previously set with iio_device_set_drvdata()
796  */
iio_device_get_drvdata(const struct iio_dev * indio_dev)797 static inline void *iio_device_get_drvdata(const struct iio_dev *indio_dev)
798 {
799 	return dev_get_drvdata(&indio_dev->dev);
800 }
801 
802 /*
803  * Used to ensure the iio_priv() structure is aligned to allow that structure
804  * to in turn include IIO_DMA_MINALIGN'd elements such as buffers which
805  * must not share  cachelines with the rest of the structure, thus making
806  * them safe for use with non-coherent DMA.
807  */
808 #define IIO_DMA_MINALIGN ARCH_DMA_MINALIGN
809 struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv);
810 
811 /* The information at the returned address is guaranteed to be cacheline aligned */
iio_priv(const struct iio_dev * indio_dev)812 static inline void *iio_priv(const struct iio_dev *indio_dev)
813 {
814 	return ACCESS_PRIVATE(indio_dev, priv);
815 }
816 
817 void iio_device_free(struct iio_dev *indio_dev);
818 struct iio_dev *devm_iio_device_alloc(struct device *parent, int sizeof_priv);
819 
820 #define devm_iio_trigger_alloc(parent, fmt, ...) \
821 	__devm_iio_trigger_alloc((parent), THIS_MODULE, (fmt), ##__VA_ARGS__)
822 __printf(3, 4)
823 struct iio_trigger *__devm_iio_trigger_alloc(struct device *parent,
824 					     struct module *this_mod,
825 					     const char *fmt, ...);
826 /**
827  * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
828  * @indio_dev:		IIO device structure for device
829  **/
830 #if defined(CONFIG_DEBUG_FS)
831 struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev);
832 #else
iio_get_debugfs_dentry(struct iio_dev * indio_dev)833 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
834 {
835 	return NULL;
836 }
837 #endif
838 
839 /**
840  * iio_device_suspend_triggering() - suspend trigger attached to an iio_dev
841  * @indio_dev: iio_dev associated with the device that will have triggers suspended
842  *
843  * Return 0 if successful, negative otherwise
844  **/
845 int iio_device_suspend_triggering(struct iio_dev *indio_dev);
846 
847 /**
848  * iio_device_resume_triggering() - resume trigger attached to an iio_dev
849  *	that was previously suspended with iio_device_suspend_triggering()
850  * @indio_dev: iio_dev associated with the device that will have triggers resumed
851  *
852  * Return 0 if successful, negative otherwise
853  **/
854 int iio_device_resume_triggering(struct iio_dev *indio_dev);
855 
856 #ifdef CONFIG_ACPI
857 bool iio_read_acpi_mount_matrix(struct device *dev,
858 				struct iio_mount_matrix *orientation,
859 				char *acpi_method);
860 const char *iio_get_acpi_device_name_and_data(struct device *dev, const void **data);
861 #else
iio_read_acpi_mount_matrix(struct device * dev,struct iio_mount_matrix * orientation,char * acpi_method)862 static inline bool iio_read_acpi_mount_matrix(struct device *dev,
863 					      struct iio_mount_matrix *orientation,
864 					      char *acpi_method)
865 {
866 	return false;
867 }
868 static inline const char *
iio_get_acpi_device_name_and_data(struct device * dev,const void ** data)869 iio_get_acpi_device_name_and_data(struct device *dev, const void **data)
870 {
871 	return NULL;
872 }
873 #endif
iio_get_acpi_device_name(struct device * dev)874 static inline const char *iio_get_acpi_device_name(struct device *dev)
875 {
876 	return iio_get_acpi_device_name_and_data(dev, NULL);
877 }
878 
879 /**
880  * iio_get_current_scan_type - Get the current scan type for a channel
881  * @indio_dev:	the IIO device to get the scan type for
882  * @chan:	the channel to get the scan type for
883  *
884  * Most devices only have one scan type per channel and can just access it
885  * directly without calling this function. Core IIO code and drivers that
886  * implement ext_scan_type in the channel spec should use this function to
887  * get the current scan type for a channel.
888  *
889  * Returns: the current scan type for the channel or error.
890  */
891 static inline const struct iio_scan_type
iio_get_current_scan_type(const struct iio_dev * indio_dev,const struct iio_chan_spec * chan)892 *iio_get_current_scan_type(const struct iio_dev *indio_dev,
893 			   const struct iio_chan_spec *chan)
894 {
895 	int ret;
896 
897 	if (chan->has_ext_scan_type) {
898 		ret = indio_dev->info->get_current_scan_type(indio_dev, chan);
899 		if (ret < 0)
900 			return ERR_PTR(ret);
901 
902 		if (ret >= chan->num_ext_scan_type)
903 			return ERR_PTR(-EINVAL);
904 
905 		return &chan->ext_scan_type[ret];
906 	}
907 
908 	return &chan->scan_type;
909 }
910 
911 /**
912  * iio_get_masklength - Get length of the channels mask
913  * @indio_dev: the IIO device to get the masklength for
914  */
iio_get_masklength(const struct iio_dev * indio_dev)915 static inline unsigned int iio_get_masklength(const struct iio_dev *indio_dev)
916 {
917 	return ACCESS_PRIVATE(indio_dev, masklength);
918 }
919 
920 int iio_active_scan_mask_index(struct iio_dev *indio_dev);
921 
922 /**
923  * iio_for_each_active_channel - Iterated over active channels
924  * @indio_dev: the IIO device
925  * @chan: Holds the index of the enabled channel
926  */
927 #define iio_for_each_active_channel(indio_dev, chan) \
928 	for_each_set_bit((chan), (indio_dev)->active_scan_mask, \
929 			 iio_get_masklength(indio_dev))
930 
931 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals);
932 
933 int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
934 	int *fract);
935 
936 /**
937  * IIO_DEGREE_TO_RAD() - Convert degree to rad
938  * @deg: A value in degree
939  *
940  * Returns the given value converted from degree to rad
941  */
942 #define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
943 
944 /**
945  * IIO_RAD_TO_DEGREE() - Convert rad to degree
946  * @rad: A value in rad
947  *
948  * Returns the given value converted from rad to degree
949  */
950 #define IIO_RAD_TO_DEGREE(rad) \
951 	(((rad) * 18000000ULL + 314159ULL / 2) / 314159ULL)
952 
953 /**
954  * IIO_G_TO_M_S_2() - Convert g to meter / second**2
955  * @g: A value in g
956  *
957  * Returns the given value converted from g to meter / second**2
958  */
959 #define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
960 
961 /**
962  * IIO_M_S_2_TO_G() - Convert meter / second**2 to g
963  * @ms2: A value in meter / second**2
964  *
965  * Returns the given value converted from meter / second**2 to g
966  */
967 #define IIO_M_S_2_TO_G(ms2) (((ms2) * 100000ULL + 980665ULL / 2) / 980665ULL)
968 
969 #endif /* _INDUSTRIAL_IO_H_ */
970