2 /* The industrial I/O core
4 * Copyright (c) 2008 Jonathan Cameron
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.
10 #ifndef _INDUSTRIAL_IO_H_
11 #define _INDUSTRIAL_IO_H_
13 #include <linux/device.h>
14 #include <linux/cdev.h>
15 #include <linux/iio/types.h>
18 * Provide means of adjusting timer accuracy.
19 * Currently assumes nano seconds.
22 enum iio_chan_info_enum {
23 IIO_CHAN_INFO_RAW = 0,
24 IIO_CHAN_INFO_PROCESSED,
27 IIO_CHAN_INFO_CALIBSCALE,
28 IIO_CHAN_INFO_CALIBBIAS,
30 IIO_CHAN_INFO_PEAK_SCALE,
31 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW,
32 IIO_CHAN_INFO_AVERAGE_RAW,
33 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY,
34 IIO_CHAN_INFO_SAMP_FREQ,
35 IIO_CHAN_INFO_FREQUENCY,
37 IIO_CHAN_INFO_HARDWAREGAIN,
38 IIO_CHAN_INFO_HYSTERESIS,
39 IIO_CHAN_INFO_INT_TIME,
59 * struct iio_chan_spec_ext_info - Extended channel info attribute
60 * @name: Info attribute name
61 * @shared: Whether this attribute is shared between all channels.
62 * @read: Read callback for this info attribute, may be NULL.
63 * @write: Write callback for this info attribute, may be NULL.
64 * @private: Data private to the driver.
66 struct iio_chan_spec_ext_info {
68 enum iio_shared_by shared;
69 ssize_t (*read)(struct iio_dev *, uintptr_t private,
70 struct iio_chan_spec const *, char *buf);
71 ssize_t (*write)(struct iio_dev *, uintptr_t private,
72 struct iio_chan_spec const *, const char *buf,
78 * struct iio_enum - Enum channel info attribute
79 * @items: An array of strings.
80 * @num_items: Length of the item array.
81 * @set: Set callback function, may be NULL.
82 * @get: Get callback function, may be NULL.
84 * The iio_enum struct can be used to implement enum style channel attributes.
85 * Enum style attributes are those which have a set of strings which map to
86 * unsigned integer values. The IIO enum helper code takes care of mapping
87 * between value and string as well as generating a "_available" file which
88 * contains a list of all available items. The set callback will be called when
89 * the attribute is updated. The last parameter is the index to the newly
90 * activated item. The get callback will be used to query the currently active
91 * item and is supposed to return the index for it.
94 const char * const *items;
95 unsigned int num_items;
96 int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
97 int (*get)(struct iio_dev *, const struct iio_chan_spec *);
100 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
101 uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
102 ssize_t iio_enum_read(struct iio_dev *indio_dev,
103 uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
104 ssize_t iio_enum_write(struct iio_dev *indio_dev,
105 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
109 * IIO_ENUM() - Initialize enum extended channel attribute
110 * @_name: Attribute name
111 * @_shared: Whether the attribute is shared between all channels
112 * @_e: Pointer to an iio_enum struct
114 * This should usually be used together with IIO_ENUM_AVAILABLE()
116 #define IIO_ENUM(_name, _shared, _e) \
119 .shared = (_shared), \
120 .read = iio_enum_read, \
121 .write = iio_enum_write, \
122 .private = (uintptr_t)(_e), \
126 * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
127 * @_name: Attribute name ("_available" will be appended to the name)
128 * @_e: Pointer to an iio_enum struct
130 * Creates a read only attribute which lists all the available enum items in a
131 * space separated list. This should usually be used together with IIO_ENUM()
133 #define IIO_ENUM_AVAILABLE(_name, _e) \
135 .name = (_name "_available"), \
136 .shared = IIO_SHARED_BY_TYPE, \
137 .read = iio_enum_available_read, \
138 .private = (uintptr_t)(_e), \
142 * struct iio_chan_spec - specification of a single channel
143 * @type: What type of measurement is the channel making.
144 * @channel: What number do we wish to assign the channel.
145 * @channel2: If there is a second number for a differential
146 * channel then this is it. If modified is set then the
147 * value here specifies the modifier.
148 * @address: Driver specific identifier.
149 * @scan_index: Monotonic index to give ordering in scans when read
151 * @scan_type: Sign: 's' or 'u' to specify signed or unsigned
152 * realbits: Number of valid bits of data
153 * storage_bits: Realbits + padding
154 * shift: Shift right by this before masking out
156 * endianness: little or big endian
157 * @info_mask_separate: What information is to be exported that is specific to
159 * @info_mask_shared_by_type: What information is to be exported that is shared
160 * by all channels of the same type.
161 * @info_mask_shared_by_dir: What information is to be exported that is shared
162 * by all channels of the same direction.
163 * @info_mask_shared_by_all: What information is to be exported that is shared
165 * @event_mask: What events can this channel produce.
166 * @ext_info: Array of extended info attributes for this channel.
167 * The array is NULL terminated, the last element should
168 * have its name field set to NULL.
169 * @extend_name: Allows labeling of channel attributes with an
170 * informative name. Note this has no effect codes etc,
172 * @datasheet_name: A name used in in-kernel mapping of channels. It should
173 * correspond to the first name that the channel is referred
174 * to by in the datasheet (e.g. IND), or the nearest
175 * possible compound name (e.g. IND-INC).
176 * @modified: Does a modifier apply to this channel. What these are
177 * depends on the channel type. Modifier is set in
178 * channel2. Examples are IIO_MOD_X for axial sensors about
180 * @indexed: Specify the channel has a numerical index. If not,
181 * the channel index number will be suppressed for sysfs
182 * attributes but not for event codes.
183 * @output: Channel is output.
184 * @differential: Channel is differential.
186 struct iio_chan_spec {
187 enum iio_chan_type type;
190 unsigned long address;
197 enum iio_endian endianness;
199 long info_mask_separate;
200 long info_mask_shared_by_type;
201 long info_mask_shared_by_dir;
202 long info_mask_shared_by_all;
204 const struct iio_chan_spec_ext_info *ext_info;
205 const char *extend_name;
206 const char *datasheet_name;
210 unsigned differential:1;
215 * iio_channel_has_info() - Checks whether a channel supports a info attribute
216 * @chan: The channel to be queried
217 * @type: Type of the info attribute to be checked
219 * Returns true if the channels supports reporting values for the given info
220 * attribute type, false otherwise.
222 static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
223 enum iio_chan_info_enum type)
225 return (chan->info_mask_separate & BIT(type)) |
226 (chan->info_mask_shared_by_type & BIT(type)) |
227 (chan->info_mask_shared_by_dir & BIT(type)) |
228 (chan->info_mask_shared_by_all & BIT(type));
231 #define IIO_ST(si, rb, sb, sh) \
232 { .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
234 #define IIO_CHAN_SOFT_TIMESTAMP(_si) \
235 { .type = IIO_TIMESTAMP, .channel = -1, \
236 .scan_index = _si, .scan_type = IIO_ST('s', 64, 64, 0) }
239 * iio_get_time_ns() - utility function to get a time stamp for events etc
241 static inline s64 iio_get_time_ns(void)
245 * calls getnstimeofday.
246 * If hrtimers then up to ns accurate, if not microsecond.
248 ktime_get_real_ts(&ts);
250 return timespec_to_ns(&ts);
253 /* Device operating modes */
254 #define INDIO_DIRECT_MODE 0x01
255 #define INDIO_BUFFER_TRIGGERED 0x02
256 #define INDIO_BUFFER_HARDWARE 0x08
258 #define INDIO_ALL_BUFFER_MODES \
259 (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE)
261 struct iio_trigger; /* forward declaration */
265 * struct iio_info - constant information about device
266 * @driver_module: module structure used to ensure correct
267 * ownership of chrdevs etc
268 * @event_attrs: event control attributes
269 * @attrs: general purpose device attributes
270 * @read_raw: function to request a value from the device.
271 * mask specifies which value. Note 0 means a reading of
272 * the channel in question. Return value will specify the
273 * type of value returned by the device. val and val2 will
274 * contain the elements making up the returned value.
275 * @write_raw: function to write a value to the device.
276 * Parameters are the same as for read_raw.
277 * @write_raw_get_fmt: callback function to query the expected
278 * format/precision. If not set by the driver, write_raw
279 * returns IIO_VAL_INT_PLUS_MICRO.
280 * @read_event_config: find out if the event is enabled.
281 * @write_event_config: set if the event is enabled.
282 * @read_event_value: read a value associated with the event. Meaning
283 * is event dependant. event_code specifies which event.
284 * @write_event_value: write the value associated with the event.
285 * Meaning is event dependent.
286 * @validate_trigger: function to validate the trigger when the
287 * current trigger gets changed.
288 * @update_scan_mode: function to configure device and scan buffer when
289 * channels have changed
290 * @debugfs_reg_access: function to read or write register value of device
293 struct module *driver_module;
294 struct attribute_group *event_attrs;
295 const struct attribute_group *attrs;
297 int (*read_raw)(struct iio_dev *indio_dev,
298 struct iio_chan_spec const *chan,
303 int (*write_raw)(struct iio_dev *indio_dev,
304 struct iio_chan_spec const *chan,
309 int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
310 struct iio_chan_spec const *chan,
313 int (*read_event_config)(struct iio_dev *indio_dev,
316 int (*write_event_config)(struct iio_dev *indio_dev,
320 int (*read_event_value)(struct iio_dev *indio_dev,
323 int (*write_event_value)(struct iio_dev *indio_dev,
326 int (*validate_trigger)(struct iio_dev *indio_dev,
327 struct iio_trigger *trig);
328 int (*update_scan_mode)(struct iio_dev *indio_dev,
329 const unsigned long *scan_mask);
330 int (*debugfs_reg_access)(struct iio_dev *indio_dev,
331 unsigned reg, unsigned writeval,
336 * struct iio_buffer_setup_ops - buffer setup related callbacks
337 * @preenable: [DRIVER] function to run prior to marking buffer enabled
338 * @postenable: [DRIVER] function to run after marking buffer enabled
339 * @predisable: [DRIVER] function to run prior to marking buffer
341 * @postdisable: [DRIVER] function to run after marking buffer disabled
342 * @validate_scan_mask: [DRIVER] function callback to check whether a given
343 * scan mask is valid for the device.
345 struct iio_buffer_setup_ops {
346 int (*preenable)(struct iio_dev *);
347 int (*postenable)(struct iio_dev *);
348 int (*predisable)(struct iio_dev *);
349 int (*postdisable)(struct iio_dev *);
350 bool (*validate_scan_mask)(struct iio_dev *indio_dev,
351 const unsigned long *scan_mask);
355 * struct iio_dev - industrial I/O device
356 * @id: [INTERN] used to identify device internally
357 * @modes: [DRIVER] operating modes supported by device
358 * @currentmode: [DRIVER] current operating mode
359 * @dev: [DRIVER] device structure, should be assigned a parent
361 * @event_interface: [INTERN] event chrdevs associated with interrupt lines
362 * @buffer: [DRIVER] any buffer present
363 * @buffer_list: [INTERN] list of all buffers currently attached
364 * @scan_bytes: [INTERN] num bytes captured to be fed to buffer demux
365 * @mlock: [INTERN] lock used to prevent simultaneous device state
367 * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
368 * @masklength: [INTERN] the length of the mask established from
370 * @active_scan_mask: [INTERN] union of all scan masks requested by buffers
371 * @scan_timestamp: [INTERN] set if any buffers have requested timestamp
372 * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
373 * @trig: [INTERN] current device trigger (buffer modes)
374 * @pollfunc: [DRIVER] function run on trigger being received
375 * @channels: [DRIVER] channel specification structure table
376 * @num_channels: [DRIVER] number of channels specified in @channels.
377 * @channel_attr_list: [INTERN] keep track of automatically created channel
379 * @chan_attr_group: [INTERN] group for all attrs in base directory
380 * @name: [DRIVER] name of the device.
381 * @info: [DRIVER] callbacks and constant info from driver
382 * @info_exist_lock: [INTERN] lock to prevent use during removal
383 * @setup_ops: [DRIVER] callbacks to call before and after buffer
385 * @chrdev: [INTERN] associated character device
386 * @groups: [INTERN] attribute groups
387 * @groupcounter: [INTERN] index of next attribute group
388 * @flags: [INTERN] file ops related flags including busy flag.
389 * @debugfs_dentry: [INTERN] device specific debugfs dentry.
390 * @cached_reg_addr: [INTERN] cached register address for debugfs reads.
399 struct iio_event_interface *event_interface;
401 struct iio_buffer *buffer;
402 struct list_head buffer_list;
406 const unsigned long *available_scan_masks;
408 const unsigned long *active_scan_mask;
410 unsigned scan_index_timestamp;
411 struct iio_trigger *trig;
412 struct iio_poll_func *pollfunc;
414 struct iio_chan_spec const *channels;
417 struct list_head channel_attr_list;
418 struct attribute_group chan_attr_group;
420 const struct iio_info *info;
421 struct mutex info_exist_lock;
422 const struct iio_buffer_setup_ops *setup_ops;
424 #define IIO_MAX_GROUPS 6
425 const struct attribute_group *groups[IIO_MAX_GROUPS + 1];
429 #if defined(CONFIG_DEBUG_FS)
430 struct dentry *debugfs_dentry;
431 unsigned cached_reg_addr;
436 * iio_find_channel_from_si() - get channel from its scan index
438 * @si: scan index to match
440 const struct iio_chan_spec
441 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
444 * iio_device_register() - register a device with the IIO subsystem
445 * @indio_dev: Device structure filled by the device driver
447 int iio_device_register(struct iio_dev *indio_dev);
450 * iio_device_unregister() - unregister a device from the IIO subsystem
451 * @indio_dev: Device structure representing the device.
453 void iio_device_unregister(struct iio_dev *indio_dev);
456 * iio_push_event() - try to add event to the list for userspace reading
457 * @indio_dev: IIO device structure
458 * @ev_code: What event
459 * @timestamp: When the event occurred
461 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
463 extern struct bus_type iio_bus_type;
466 * iio_device_put() - reference counted deallocation of struct device
467 * @indio_dev: IIO device structure containing the device
469 static inline void iio_device_put(struct iio_dev *indio_dev)
472 put_device(&indio_dev->dev);
476 * dev_to_iio_dev() - Get IIO device struct from a device struct
477 * @dev: The device embedded in the IIO device
479 * Note: The device must be a IIO device, otherwise the result is undefined.
481 static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
483 return container_of(dev, struct iio_dev, dev);
487 * iio_device_get() - increment reference count for the device
488 * @indio_dev: IIO device structure
490 * Returns: The passed IIO device
492 static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
494 return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
499 * iio_device_set_drvdata() - Set device driver data
500 * @indio_dev: IIO device structure
501 * @data: Driver specific data
503 * Allows to attach an arbitrary pointer to an IIO device, which can later be
504 * retrieved by iio_device_get_drvdata().
506 static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
508 dev_set_drvdata(&indio_dev->dev, data);
512 * iio_device_get_drvdata() - Get device driver data
513 * @indio_dev: IIO device structure
515 * Returns the data previously set with iio_device_set_drvdata()
517 static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev)
519 return dev_get_drvdata(&indio_dev->dev);
522 /* Can we make this smaller? */
523 #define IIO_ALIGN L1_CACHE_BYTES
525 * iio_device_alloc() - allocate an iio_dev from a driver
526 * @sizeof_priv: Space to allocate for private structure.
528 struct iio_dev *iio_device_alloc(int sizeof_priv);
530 static inline void *iio_priv(const struct iio_dev *indio_dev)
532 return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
535 static inline struct iio_dev *iio_priv_to_dev(void *priv)
537 return (struct iio_dev *)((char *)priv -
538 ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
542 * iio_device_free() - free an iio_dev from a driver
543 * @indio_dev: the iio_dev associated with the device
545 void iio_device_free(struct iio_dev *indio_dev);
548 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
549 * @dev: Device to allocate iio_dev for
550 * @sizeof_priv: Space to allocate for private structure.
552 * Managed iio_device_alloc. iio_dev allocated with this function is
553 * automatically freed on driver detach.
555 * If an iio_dev allocated with this function needs to be freed separately,
556 * devm_iio_device_free() must be used.
559 * Pointer to allocated iio_dev on success, NULL on failure.
561 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv);
564 * devm_iio_device_free - Resource-managed iio_device_free()
565 * @dev: Device this iio_dev belongs to
566 * @indio_dev: the iio_dev associated with the device
568 * Free iio_dev allocated with devm_iio_device_alloc().
570 void devm_iio_device_free(struct device *dev, struct iio_dev *indio_dev);
573 * devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc()
574 * @dev: Device to allocate iio_trigger for
575 * @fmt: trigger name format. If it includes format
576 * specifiers, the additional arguments following
577 * format are formatted and inserted in the resulting
578 * string replacing their respective specifiers.
580 * Managed iio_trigger_alloc. iio_trigger allocated with this function is
581 * automatically freed on driver detach.
583 * If an iio_trigger allocated with this function needs to be freed separately,
584 * devm_iio_trigger_free() must be used.
587 * Pointer to allocated iio_trigger on success, NULL on failure.
589 struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
590 const char *fmt, ...);
593 * devm_iio_trigger_free - Resource-managed iio_trigger_free()
594 * @dev: Device this iio_dev belongs to
595 * @iio_trig: the iio_trigger associated with the device
597 * Free iio_trigger allocated with devm_iio_trigger_alloc().
599 void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig);
602 * iio_buffer_enabled() - helper function to test if the buffer is enabled
603 * @indio_dev: IIO device structure for device
605 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
607 return indio_dev->currentmode
608 & (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE);
612 * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
613 * @indio_dev: IIO device structure for device
615 #if defined(CONFIG_DEBUG_FS)
616 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
618 return indio_dev->debugfs_dentry;
621 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
627 int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
631 * IIO_DEGREE_TO_RAD() - Convert degree to rad
632 * @deg: A value in degree
634 * Returns the given value converted from degree to rad
636 #define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
639 * IIO_G_TO_M_S_2() - Convert g to meter / second**2
642 * Returns the given value converted from g to meter / second**2
644 #define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
646 #endif /* _INDUSTRIAL_IO_H_ */