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/slab.h>
13  #include <linux/iio/types.h>
14  /* IIO TODO LIST */
15  /*
16   * Provide means of adjusting timer accuracy.
17   * Currently assumes nano seconds.
18   */
19  
20  struct fwnode_reference_args;
21  
22  enum iio_shared_by {
23  	IIO_SEPARATE,
24  	IIO_SHARED_BY_TYPE,
25  	IIO_SHARED_BY_DIR,
26  	IIO_SHARED_BY_ALL
27  };
28  
29  enum iio_endian {
30  	IIO_CPU,
31  	IIO_BE,
32  	IIO_LE,
33  };
34  
35  struct iio_chan_spec;
36  struct iio_dev;
37  
38  /**
39   * struct iio_chan_spec_ext_info - Extended channel info attribute
40   * @name:	Info attribute name
41   * @shared:	Whether this attribute is shared between all channels.
42   * @read:	Read callback for this info attribute, may be NULL.
43   * @write:	Write callback for this info attribute, may be NULL.
44   * @private:	Data private to the driver.
45   */
46  struct iio_chan_spec_ext_info {
47  	const char *name;
48  	enum iio_shared_by shared;
49  	ssize_t (*read)(struct iio_dev *, uintptr_t private,
50  			struct iio_chan_spec const *, char *buf);
51  	ssize_t (*write)(struct iio_dev *, uintptr_t private,
52  			 struct iio_chan_spec const *, const char *buf,
53  			 size_t len);
54  	uintptr_t private;
55  };
56  
57  /**
58   * struct iio_enum - Enum channel info attribute
59   * @items:	An array of strings.
60   * @num_items:	Length of the item array.
61   * @set:	Set callback function, may be NULL.
62   * @get:	Get callback function, may be NULL.
63   *
64   * The iio_enum struct can be used to implement enum style channel attributes.
65   * Enum style attributes are those which have a set of strings which map to
66   * unsigned integer values. The IIO enum helper code takes care of mapping
67   * between value and string as well as generating a "_available" file which
68   * contains a list of all available items. The set callback will be called when
69   * the attribute is updated. The last parameter is the index to the newly
70   * activated item. The get callback will be used to query the currently active
71   * item and is supposed to return the index for it.
72   */
73  struct iio_enum {
74  	const char * const *items;
75  	unsigned int num_items;
76  	int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
77  	int (*get)(struct iio_dev *, const struct iio_chan_spec *);
78  };
79  
80  ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
81  	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
82  ssize_t iio_enum_read(struct iio_dev *indio_dev,
83  	uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
84  ssize_t iio_enum_write(struct iio_dev *indio_dev,
85  	uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
86  	size_t len);
87  
88  /**
89   * IIO_ENUM() - Initialize enum extended channel attribute
90   * @_name:	Attribute name
91   * @_shared:	Whether the attribute is shared between all channels
92   * @_e:		Pointer to an iio_enum struct
93   *
94   * This should usually be used together with IIO_ENUM_AVAILABLE()
95   */
96  #define IIO_ENUM(_name, _shared, _e) \
97  { \
98  	.name = (_name), \
99  	.shared = (_shared), \
100  	.read = iio_enum_read, \
101  	.write = iio_enum_write, \
102  	.private = (uintptr_t)(_e), \
103  }
104  
105  /**
106   * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
107   * @_name:	Attribute name ("_available" will be appended to the name)
108   * @_shared:	Whether the attribute is shared between all channels
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, _shared, _e) \
115  { \
116  	.name = (_name "_available"), \
117  	.shared = _shared, \
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 iio_read_mount_matrix(struct device *dev, struct iio_mount_matrix *matrix);
134  
135  typedef const struct iio_mount_matrix *
136  	(iio_get_mount_matrix_t)(const struct iio_dev *indio_dev,
137  				 const struct iio_chan_spec *chan);
138  
139  /**
140   * IIO_MOUNT_MATRIX() - Initialize mount matrix extended channel attribute
141   * @_shared:	Whether the attribute is shared between all channels
142   * @_get:	Pointer to an iio_get_mount_matrix_t accessor
143   */
144  #define IIO_MOUNT_MATRIX(_shared, _get) \
145  { \
146  	.name = "mount_matrix", \
147  	.shared = (_shared), \
148  	.read = iio_show_mount_matrix, \
149  	.private = (uintptr_t)(_get), \
150  }
151  
152  /**
153   * struct iio_event_spec - specification for a channel event
154   * @type:		    Type of the event
155   * @dir:		    Direction of the event
156   * @mask_separate:	    Bit mask of enum iio_event_info values. Attributes
157   *			    set in this mask will be registered per channel.
158   * @mask_shared_by_type:    Bit mask of enum iio_event_info values. Attributes
159   *			    set in this mask will be shared by channel type.
160   * @mask_shared_by_dir:	    Bit mask of enum iio_event_info values. Attributes
161   *			    set in this mask will be shared by channel type and
162   *			    direction.
163   * @mask_shared_by_all:	    Bit mask of enum iio_event_info values. Attributes
164   *			    set in this mask will be shared by all channels.
165   */
166  struct iio_event_spec {
167  	enum iio_event_type type;
168  	enum iio_event_direction dir;
169  	unsigned long mask_separate;
170  	unsigned long mask_shared_by_type;
171  	unsigned long mask_shared_by_dir;
172  	unsigned long mask_shared_by_all;
173  };
174  
175  /**
176   * struct iio_chan_spec - specification of a single channel
177   * @type:		What type of measurement is the channel making.
178   * @channel:		What number do we wish to assign the channel.
179   * @channel2:		If there is a second number for a differential
180   *			channel then this is it. If modified is set then the
181   *			value here specifies the modifier.
182   * @address:		Driver specific identifier.
183   * @scan_index:		Monotonic index to give ordering in scans when read
184   *			from a buffer.
185   * @scan_type:		struct describing the scan type
186   * @scan_type.sign:		's' or 'u' to specify signed or unsigned
187   * @scan_type.realbits:		Number of valid bits of data
188   * @scan_type.storagebits:	Realbits + padding
189   * @scan_type.shift:		Shift right by this before masking out
190   *				realbits.
191   * @scan_type.repeat:		Number of times real/storage bits repeats.
192   *				When the repeat element is more than 1, then
193   *				the type element in sysfs will show a repeat
194   *				value. Otherwise, the number of repetitions
195   *				is omitted.
196   * @scan_type.endianness:	little or big endian
197   * @info_mask_separate: What information is to be exported that is specific to
198   *			this channel.
199   * @info_mask_separate_available: What availability information is to be
200   *			exported that is specific to this channel.
201   * @info_mask_shared_by_type: What information is to be exported that is shared
202   *			by all channels of the same type.
203   * @info_mask_shared_by_type_available: What availability information is to be
204   *			exported that is shared by all channels of the same
205   *			type.
206   * @info_mask_shared_by_dir: What information is to be exported that is shared
207   *			by all channels of the same direction.
208   * @info_mask_shared_by_dir_available: What availability information is to be
209   *			exported that is shared by all channels of the same
210   *			direction.
211   * @info_mask_shared_by_all: What information is to be exported that is shared
212   *			by all channels.
213   * @info_mask_shared_by_all_available: What availability information is to be
214   *			exported that is shared by all channels.
215   * @event_spec:		Array of events which should be registered for this
216   *			channel.
217   * @num_event_specs:	Size of the event_spec array.
218   * @ext_info:		Array of extended info attributes for this channel.
219   *			The array is NULL terminated, the last element should
220   *			have its name field set to NULL.
221   * @extend_name:	Allows labeling of channel attributes with an
222   *			informative name. Note this has no effect codes etc,
223   *			unlike modifiers.
224   * @datasheet_name:	A name used in in-kernel mapping of channels. It should
225   *			correspond to the first name that the channel is referred
226   *			to by in the datasheet (e.g. IND), or the nearest
227   *			possible compound name (e.g. IND-INC).
228   * @modified:		Does a modifier apply to this channel. What these are
229   *			depends on the channel type.  Modifier is set in
230   *			channel2. Examples are IIO_MOD_X for axial sensors about
231   *			the 'x' axis.
232   * @indexed:		Specify the channel has a numerical index. If not,
233   *			the channel index number will be suppressed for sysfs
234   *			attributes but not for event codes.
235   * @output:		Channel is output.
236   * @differential:	Channel is differential.
237   */
238  struct iio_chan_spec {
239  	enum iio_chan_type	type;
240  	int			channel;
241  	int			channel2;
242  	unsigned long		address;
243  	int			scan_index;
244  	struct {
245  		char	sign;
246  		u8	realbits;
247  		u8	storagebits;
248  		u8	shift;
249  		u8	repeat;
250  		enum iio_endian endianness;
251  	} scan_type;
252  	long			info_mask_separate;
253  	long			info_mask_separate_available;
254  	long			info_mask_shared_by_type;
255  	long			info_mask_shared_by_type_available;
256  	long			info_mask_shared_by_dir;
257  	long			info_mask_shared_by_dir_available;
258  	long			info_mask_shared_by_all;
259  	long			info_mask_shared_by_all_available;
260  	const struct iio_event_spec *event_spec;
261  	unsigned int		num_event_specs;
262  	const struct iio_chan_spec_ext_info *ext_info;
263  	const char		*extend_name;
264  	const char		*datasheet_name;
265  	unsigned		modified:1;
266  	unsigned		indexed:1;
267  	unsigned		output:1;
268  	unsigned		differential:1;
269  };
270  
271  
272  /**
273   * iio_channel_has_info() - Checks whether a channel supports a info attribute
274   * @chan: The channel to be queried
275   * @type: Type of the info attribute to be checked
276   *
277   * Returns true if the channels supports reporting values for the given info
278   * attribute type, false otherwise.
279   */
iio_channel_has_info(const struct iio_chan_spec * chan,enum iio_chan_info_enum type)280  static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
281  	enum iio_chan_info_enum type)
282  {
283  	return (chan->info_mask_separate & BIT(type)) |
284  		(chan->info_mask_shared_by_type & BIT(type)) |
285  		(chan->info_mask_shared_by_dir & BIT(type)) |
286  		(chan->info_mask_shared_by_all & BIT(type));
287  }
288  
289  /**
290   * iio_channel_has_available() - Checks if a channel has an available attribute
291   * @chan: The channel to be queried
292   * @type: Type of the available attribute to be checked
293   *
294   * Returns true if the channel supports reporting available values for the
295   * given attribute type, false otherwise.
296   */
iio_channel_has_available(const struct iio_chan_spec * chan,enum iio_chan_info_enum type)297  static inline bool iio_channel_has_available(const struct iio_chan_spec *chan,
298  					     enum iio_chan_info_enum type)
299  {
300  	return (chan->info_mask_separate_available & BIT(type)) |
301  		(chan->info_mask_shared_by_type_available & BIT(type)) |
302  		(chan->info_mask_shared_by_dir_available & BIT(type)) |
303  		(chan->info_mask_shared_by_all_available & BIT(type));
304  }
305  
306  #define IIO_CHAN_SOFT_TIMESTAMP(_si) {					\
307  	.type = IIO_TIMESTAMP,						\
308  	.channel = -1,							\
309  	.scan_index = _si,						\
310  	.scan_type = {							\
311  		.sign = 's',						\
312  		.realbits = 64,					\
313  		.storagebits = 64,					\
314  		},							\
315  }
316  
317  s64 iio_get_time_ns(const struct iio_dev *indio_dev);
318  
319  /*
320   * Device operating modes
321   * @INDIO_DIRECT_MODE: There is an access to either:
322   * a) The last single value available for devices that do not provide
323   *    on-demand reads.
324   * b) A new value after performing an on-demand read otherwise.
325   * On most devices, this is a single-shot read. On some devices with data
326   * streams without an 'on-demand' function, this might also be the 'last value'
327   * feature. Above all, this mode internally means that we are not in any of the
328   * other modes, and sysfs reads should work.
329   * Device drivers should inform the core if they support this mode.
330   * @INDIO_BUFFER_TRIGGERED: Common mode when dealing with kfifo buffers.
331   * It indicates that an explicit trigger is required. This requests the core to
332   * attach a poll function when enabling the buffer, which is indicated by the
333   * _TRIGGERED suffix.
334   * The core will ensure this mode is set when registering a triggered buffer
335   * with iio_triggered_buffer_setup().
336   * @INDIO_BUFFER_SOFTWARE: Another kfifo buffer mode, but not event triggered.
337   * No poll function can be attached because there is no triggered infrastructure
338   * we can use to cause capture. There is a kfifo that the driver will fill, but
339   * not "only one scan at a time". Typically, hardware will have a buffer that
340   * can hold multiple scans. Software may read one or more scans at a single time
341   * and push the available data to a Kfifo. This means the core will not attach
342   * any poll function when enabling the buffer.
343   * The core will ensure this mode is set when registering a simple kfifo buffer
344   * with devm_iio_kfifo_buffer_setup().
345   * @INDIO_BUFFER_HARDWARE: For specific hardware, if unsure do not use this mode.
346   * Same as above but this time the buffer is not a kfifo where we have direct
347   * access to the data. Instead, the consumer driver must access the data through
348   * non software visible channels (or DMA when there is no demux possible in
349   * software)
350   * The core will ensure this mode is set when registering a dmaengine buffer
351   * with devm_iio_dmaengine_buffer_setup().
352   * @INDIO_EVENT_TRIGGERED: Very unusual mode.
353   * Triggers usually refer to an external event which will start data capture.
354   * Here it is kind of the opposite as, a particular state of the data might
355   * produce an event which can be considered as an event. We don't necessarily
356   * have access to the data itself, but to the event produced. For example, this
357   * can be a threshold detector. The internal path of this mode is very close to
358   * the INDIO_BUFFER_TRIGGERED mode.
359   * The core will ensure this mode is set when registering a triggered event.
360   * @INDIO_HARDWARE_TRIGGERED: Very unusual mode.
361   * Here, triggers can result in data capture and can be routed to multiple
362   * hardware components, which make them close to regular triggers in the way
363   * they must be managed by the core, but without the entire interrupts/poll
364   * functions burden. Interrupts are irrelevant as the data flow is hardware
365   * mediated and distributed.
366   */
367  #define INDIO_DIRECT_MODE		0x01
368  #define INDIO_BUFFER_TRIGGERED		0x02
369  #define INDIO_BUFFER_SOFTWARE		0x04
370  #define INDIO_BUFFER_HARDWARE		0x08
371  #define INDIO_EVENT_TRIGGERED		0x10
372  #define INDIO_HARDWARE_TRIGGERED	0x20
373  
374  #define INDIO_ALL_BUFFER_MODES					\
375  	(INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE | INDIO_BUFFER_SOFTWARE)
376  
377  #define INDIO_ALL_TRIGGERED_MODES	\
378  	(INDIO_BUFFER_TRIGGERED		\
379  	 | INDIO_EVENT_TRIGGERED	\
380  	 | INDIO_HARDWARE_TRIGGERED)
381  
382  #define INDIO_MAX_RAW_ELEMENTS		4
383  
384  struct iio_val_int_plus_micro {
385  	int integer;
386  	int micro;
387  };
388  
389  struct iio_trigger; /* forward declaration */
390  
391  /**
392   * struct iio_info - constant information about device
393   * @event_attrs:	event control attributes
394   * @attrs:		general purpose device attributes
395   * @read_raw:		function to request a value from the device.
396   *			mask specifies which value. Note 0 means a reading of
397   *			the channel in question.  Return value will specify the
398   *			type of value returned by the device. val and val2 will
399   *			contain the elements making up the returned value.
400   * @read_raw_multi:	function to return values from the device.
401   *			mask specifies which value. Note 0 means a reading of
402   *			the channel in question.  Return value will specify the
403   *			type of value returned by the device. vals pointer
404   *			contain the elements making up the returned value.
405   *			max_len specifies maximum number of elements
406   *			vals pointer can contain. val_len is used to return
407   *			length of valid elements in vals.
408   * @read_avail:		function to return the available values from the device.
409   *			mask specifies which value. Note 0 means the available
410   *			values for the channel in question.  Return value
411   *			specifies if a IIO_AVAIL_LIST or a IIO_AVAIL_RANGE is
412   *			returned in vals. The type of the vals are returned in
413   *			type and the number of vals is returned in length. For
414   *			ranges, there are always three vals returned; min, step
415   *			and max. For lists, all possible values are enumerated.
416   * @write_raw:		function to write a value to the device.
417   *			Parameters are the same as for read_raw.
418   * @read_label:		function to request label name for a specified label,
419   *			for better channel identification.
420   * @write_raw_get_fmt:	callback function to query the expected
421   *			format/precision. If not set by the driver, write_raw
422   *			returns IIO_VAL_INT_PLUS_MICRO.
423   * @read_event_config:	find out if the event is enabled.
424   * @write_event_config:	set if the event is enabled.
425   * @read_event_value:	read a configuration value associated with the event.
426   * @write_event_value:	write a configuration value for the event.
427   * @validate_trigger:	function to validate the trigger when the
428   *			current trigger gets changed.
429   * @update_scan_mode:	function to configure device and scan buffer when
430   *			channels have changed
431   * @debugfs_reg_access:	function to read or write register value of device
432   * @of_xlate:		function pointer to obtain channel specifier index.
433   *			When #iio-cells is greater than '0', the driver could
434   *			provide a custom of_xlate function that reads the
435   *			*args* and returns the appropriate index in registered
436   *			IIO channels array.
437   * @fwnode_xlate:	fwnode based function pointer to obtain channel specifier index.
438   *			Functionally the same as @of_xlate.
439   * @hwfifo_set_watermark: function pointer to set the current hardware
440   *			fifo watermark level; see hwfifo_* entries in
441   *			Documentation/ABI/testing/sysfs-bus-iio for details on
442   *			how the hardware fifo operates
443   * @hwfifo_flush_to_buffer: function pointer to flush the samples stored
444   *			in the hardware fifo to the device buffer. The driver
445   *			should not flush more than count samples. The function
446   *			must return the number of samples flushed, 0 if no
447   *			samples were flushed or a negative integer if no samples
448   *			were flushed and there was an error.
449   **/
450  struct iio_info {
451  	const struct attribute_group	*event_attrs;
452  	const struct attribute_group	*attrs;
453  
454  	int (*read_raw)(struct iio_dev *indio_dev,
455  			struct iio_chan_spec const *chan,
456  			int *val,
457  			int *val2,
458  			long mask);
459  
460  	int (*read_raw_multi)(struct iio_dev *indio_dev,
461  			struct iio_chan_spec const *chan,
462  			int max_len,
463  			int *vals,
464  			int *val_len,
465  			long mask);
466  
467  	int (*read_avail)(struct iio_dev *indio_dev,
468  			  struct iio_chan_spec const *chan,
469  			  const int **vals,
470  			  int *type,
471  			  int *length,
472  			  long mask);
473  
474  	int (*write_raw)(struct iio_dev *indio_dev,
475  			 struct iio_chan_spec const *chan,
476  			 int val,
477  			 int val2,
478  			 long mask);
479  
480  	int (*read_label)(struct iio_dev *indio_dev,
481  			 struct iio_chan_spec const *chan,
482  			 char *label);
483  
484  	int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
485  			 struct iio_chan_spec const *chan,
486  			 long mask);
487  
488  	int (*read_event_config)(struct iio_dev *indio_dev,
489  				 const struct iio_chan_spec *chan,
490  				 enum iio_event_type type,
491  				 enum iio_event_direction dir);
492  
493  	int (*write_event_config)(struct iio_dev *indio_dev,
494  				  const struct iio_chan_spec *chan,
495  				  enum iio_event_type type,
496  				  enum iio_event_direction dir,
497  				  int state);
498  
499  	int (*read_event_value)(struct iio_dev *indio_dev,
500  				const struct iio_chan_spec *chan,
501  				enum iio_event_type type,
502  				enum iio_event_direction dir,
503  				enum iio_event_info info, int *val, int *val2);
504  
505  	int (*write_event_value)(struct iio_dev *indio_dev,
506  				 const struct iio_chan_spec *chan,
507  				 enum iio_event_type type,
508  				 enum iio_event_direction dir,
509  				 enum iio_event_info info, int val, int val2);
510  
511  	int (*validate_trigger)(struct iio_dev *indio_dev,
512  				struct iio_trigger *trig);
513  	int (*update_scan_mode)(struct iio_dev *indio_dev,
514  				const unsigned long *scan_mask);
515  	int (*debugfs_reg_access)(struct iio_dev *indio_dev,
516  				  unsigned reg, unsigned writeval,
517  				  unsigned *readval);
518  	int (*fwnode_xlate)(struct iio_dev *indio_dev,
519  			    const struct fwnode_reference_args *iiospec);
520  	int (*hwfifo_set_watermark)(struct iio_dev *indio_dev, unsigned val);
521  	int (*hwfifo_flush_to_buffer)(struct iio_dev *indio_dev,
522  				      unsigned count);
523  };
524  
525  /**
526   * struct iio_buffer_setup_ops - buffer setup related callbacks
527   * @preenable:		[DRIVER] function to run prior to marking buffer enabled
528   * @postenable:		[DRIVER] function to run after marking buffer enabled
529   * @predisable:		[DRIVER] function to run prior to marking buffer
530   *			disabled
531   * @postdisable:	[DRIVER] function to run after marking buffer disabled
532   * @validate_scan_mask: [DRIVER] function callback to check whether a given
533   *			scan mask is valid for the device.
534   */
535  struct iio_buffer_setup_ops {
536  	int (*preenable)(struct iio_dev *);
537  	int (*postenable)(struct iio_dev *);
538  	int (*predisable)(struct iio_dev *);
539  	int (*postdisable)(struct iio_dev *);
540  	bool (*validate_scan_mask)(struct iio_dev *indio_dev,
541  				   const unsigned long *scan_mask);
542  };
543  
544  /**
545   * struct iio_dev - industrial I/O device
546   * @modes:		[DRIVER] bitmask listing all the operating modes
547   *			supported by the IIO device. This list should be
548   *			initialized before registering the IIO device. It can
549   *			also be filed up by the IIO core, as a result of
550   *			enabling particular features in the driver
551   *			(see iio_triggered_event_setup()).
552   * @dev:		[DRIVER] device structure, should be assigned a parent
553   *			and owner
554   * @buffer:		[DRIVER] any buffer present
555   * @scan_bytes:		[INTERN] num bytes captured to be fed to buffer demux
556   * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
557   * @masklength:		[INTERN] the length of the mask established from
558   *			channels
559   * @active_scan_mask:	[INTERN] union of all scan masks requested by buffers
560   * @scan_timestamp:	[INTERN] set if any buffers have requested timestamp
561   * @trig:		[INTERN] current device trigger (buffer modes)
562   * @pollfunc:		[DRIVER] function run on trigger being received
563   * @pollfunc_event:	[DRIVER] function run on events trigger being received
564   * @channels:		[DRIVER] channel specification structure table
565   * @num_channels:	[DRIVER] number of channels specified in @channels.
566   * @name:		[DRIVER] name of the device.
567   * @label:              [DRIVER] unique name to identify which device this is
568   * @info:		[DRIVER] callbacks and constant info from driver
569   * @setup_ops:		[DRIVER] callbacks to call before and after buffer
570   *			enable/disable
571   * @priv:		[DRIVER] reference to driver's private information
572   *			**MUST** be accessed **ONLY** via iio_priv() helper
573   */
574  struct iio_dev {
575  	int				modes;
576  	struct device			dev;
577  
578  	struct iio_buffer		*buffer;
579  	int				scan_bytes;
580  
581  	const unsigned long		*available_scan_masks;
582  	unsigned			masklength;
583  	const unsigned long		*active_scan_mask;
584  	bool				scan_timestamp;
585  	struct iio_trigger		*trig;
586  	struct iio_poll_func		*pollfunc;
587  	struct iio_poll_func		*pollfunc_event;
588  
589  	struct iio_chan_spec const	*channels;
590  	int				num_channels;
591  
592  	const char			*name;
593  	const char			*label;
594  	const struct iio_info		*info;
595  	const struct iio_buffer_setup_ops	*setup_ops;
596  
597  	void				*priv;
598  };
599  
600  int iio_device_id(struct iio_dev *indio_dev);
601  int iio_device_get_current_mode(struct iio_dev *indio_dev);
602  bool iio_buffer_enabled(struct iio_dev *indio_dev);
603  
604  const struct iio_chan_spec
605  *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
606  /**
607   * iio_device_register() - register a device with the IIO subsystem
608   * @indio_dev:		Device structure filled by the device driver
609   **/
610  #define iio_device_register(indio_dev) \
611  	__iio_device_register((indio_dev), THIS_MODULE)
612  int __iio_device_register(struct iio_dev *indio_dev, struct module *this_mod);
613  void iio_device_unregister(struct iio_dev *indio_dev);
614  /**
615   * devm_iio_device_register - Resource-managed iio_device_register()
616   * @dev:	Device to allocate iio_dev for
617   * @indio_dev:	Device structure filled by the device driver
618   *
619   * Managed iio_device_register.  The IIO device registered with this
620   * function is automatically unregistered on driver detach. This function
621   * calls iio_device_register() internally. Refer to that function for more
622   * information.
623   *
624   * RETURNS:
625   * 0 on success, negative error number on failure.
626   */
627  #define devm_iio_device_register(dev, indio_dev) \
628  	__devm_iio_device_register((dev), (indio_dev), THIS_MODULE)
629  int __devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev,
630  			       struct module *this_mod);
631  int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
632  int iio_device_claim_direct_mode(struct iio_dev *indio_dev);
633  void iio_device_release_direct_mode(struct iio_dev *indio_dev);
634  int iio_device_claim_buffer_mode(struct iio_dev *indio_dev);
635  void iio_device_release_buffer_mode(struct iio_dev *indio_dev);
636  
637  extern struct bus_type iio_bus_type;
638  
639  /**
640   * iio_device_put() - reference counted deallocation of struct device
641   * @indio_dev: IIO device structure containing the device
642   **/
iio_device_put(struct iio_dev * indio_dev)643  static inline void iio_device_put(struct iio_dev *indio_dev)
644  {
645  	if (indio_dev)
646  		put_device(&indio_dev->dev);
647  }
648  
649  clockid_t iio_device_get_clock(const struct iio_dev *indio_dev);
650  int iio_device_set_clock(struct iio_dev *indio_dev, clockid_t clock_id);
651  
652  /**
653   * dev_to_iio_dev() - Get IIO device struct from a device struct
654   * @dev: 		The device embedded in the IIO device
655   *
656   * Note: The device must be a IIO device, otherwise the result is undefined.
657   */
dev_to_iio_dev(struct device * dev)658  static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
659  {
660  	return container_of(dev, struct iio_dev, dev);
661  }
662  
663  /**
664   * iio_device_get() - increment reference count for the device
665   * @indio_dev: 		IIO device structure
666   *
667   * Returns: The passed IIO device
668   **/
iio_device_get(struct iio_dev * indio_dev)669  static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
670  {
671  	return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
672  }
673  
674  /**
675   * iio_device_set_parent() - assign parent device to the IIO device object
676   * @indio_dev: 		IIO device structure
677   * @parent:		reference to parent device object
678   *
679   * This utility must be called between IIO device allocation
680   * (via devm_iio_device_alloc()) & IIO device registration
681   * (via iio_device_register() and devm_iio_device_register())).
682   * By default, the device allocation will also assign a parent device to
683   * the IIO device object. In cases where devm_iio_device_alloc() is used,
684   * sometimes the parent device must be different than the device used to
685   * manage the allocation.
686   * In that case, this helper should be used to change the parent, hence the
687   * requirement to call this between allocation & registration.
688   **/
iio_device_set_parent(struct iio_dev * indio_dev,struct device * parent)689  static inline void iio_device_set_parent(struct iio_dev *indio_dev,
690  					 struct device *parent)
691  {
692  	indio_dev->dev.parent = parent;
693  }
694  
695  /**
696   * iio_device_set_drvdata() - Set device driver data
697   * @indio_dev: IIO device structure
698   * @data: Driver specific data
699   *
700   * Allows to attach an arbitrary pointer to an IIO device, which can later be
701   * retrieved by iio_device_get_drvdata().
702   */
iio_device_set_drvdata(struct iio_dev * indio_dev,void * data)703  static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
704  {
705  	dev_set_drvdata(&indio_dev->dev, data);
706  }
707  
708  /**
709   * iio_device_get_drvdata() - Get device driver data
710   * @indio_dev: IIO device structure
711   *
712   * Returns the data previously set with iio_device_set_drvdata()
713   */
iio_device_get_drvdata(const struct iio_dev * indio_dev)714  static inline void *iio_device_get_drvdata(const struct iio_dev *indio_dev)
715  {
716  	return dev_get_drvdata(&indio_dev->dev);
717  }
718  
719  /*
720   * Used to ensure the iio_priv() structure is aligned to allow that structure
721   * to in turn include IIO_DMA_MINALIGN'd elements such as buffers which
722   * must not share  cachelines with the rest of the structure, thus making
723   * them safe for use with non-coherent DMA.
724   */
725  #define IIO_DMA_MINALIGN ARCH_KMALLOC_MINALIGN
726  struct iio_dev *iio_device_alloc(struct device *parent, int sizeof_priv);
727  
728  /* The information at the returned address is guaranteed to be cacheline aligned */
iio_priv(const struct iio_dev * indio_dev)729  static inline void *iio_priv(const struct iio_dev *indio_dev)
730  {
731  	return indio_dev->priv;
732  }
733  
734  void iio_device_free(struct iio_dev *indio_dev);
735  struct iio_dev *devm_iio_device_alloc(struct device *parent, int sizeof_priv);
736  
737  #define devm_iio_trigger_alloc(parent, fmt, ...) \
738  	__devm_iio_trigger_alloc((parent), THIS_MODULE, (fmt), ##__VA_ARGS__)
739  __printf(3, 4)
740  struct iio_trigger *__devm_iio_trigger_alloc(struct device *parent,
741  					     struct module *this_mod,
742  					     const char *fmt, ...);
743  /**
744   * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
745   * @indio_dev:		IIO device structure for device
746   **/
747  #if defined(CONFIG_DEBUG_FS)
748  struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev);
749  #else
iio_get_debugfs_dentry(struct iio_dev * indio_dev)750  static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
751  {
752  	return NULL;
753  }
754  #endif
755  
756  ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals);
757  
758  int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
759  	int *fract);
760  
761  /**
762   * IIO_DEGREE_TO_RAD() - Convert degree to rad
763   * @deg: A value in degree
764   *
765   * Returns the given value converted from degree to rad
766   */
767  #define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
768  
769  /**
770   * IIO_RAD_TO_DEGREE() - Convert rad to degree
771   * @rad: A value in rad
772   *
773   * Returns the given value converted from rad to degree
774   */
775  #define IIO_RAD_TO_DEGREE(rad) \
776  	(((rad) * 18000000ULL + 314159ULL / 2) / 314159ULL)
777  
778  /**
779   * IIO_G_TO_M_S_2() - Convert g to meter / second**2
780   * @g: A value in g
781   *
782   * Returns the given value converted from g to meter / second**2
783   */
784  #define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
785  
786  /**
787   * IIO_M_S_2_TO_G() - Convert meter / second**2 to g
788   * @ms2: A value in meter / second**2
789   *
790   * Returns the given value converted from meter / second**2 to g
791   */
792  #define IIO_M_S_2_TO_G(ms2) (((ms2) * 100000ULL + 980665ULL / 2) / 980665ULL)
793  
794  #endif /* _INDUSTRIAL_IO_H_ */
795