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_event_spec - specification for a channel event
143 * @type: Type of the event
144 * @dir: Direction of the event
145 * @mask_separate: Bit mask of enum iio_event_info values. Attributes
146 * set in this mask will be registered per channel.
147 * @mask_shared_by_type: Bit mask of enum iio_event_info values. Attributes
148 * set in this mask will be shared by channel type.
149 * @mask_shared_by_dir: Bit mask of enum iio_event_info values. Attributes
150 * set in this mask will be shared by channel type and
152 * @mask_shared_by_all: Bit mask of enum iio_event_info values. Attributes
153 * set in this mask will be shared by all channels.
155 struct iio_event_spec {
156 enum iio_event_type type;
157 enum iio_event_direction dir;
158 unsigned long mask_separate;
159 unsigned long mask_shared_by_type;
160 unsigned long mask_shared_by_dir;
161 unsigned long mask_shared_by_all;
165 * struct iio_chan_spec - specification of a single channel
166 * @type: What type of measurement is the channel making.
167 * @channel: What number do we wish to assign the channel.
168 * @channel2: If there is a second number for a differential
169 * channel then this is it. If modified is set then the
170 * value here specifies the modifier.
171 * @address: Driver specific identifier.
172 * @scan_index: Monotonic index to give ordering in scans when read
174 * @scan_type: Sign: 's' or 'u' to specify signed or unsigned
175 * realbits: Number of valid bits of data
176 * storage_bits: Realbits + padding
177 * shift: Shift right by this before masking out
179 * endianness: little or big endian
180 * @info_mask_separate: What information is to be exported that is specific to
182 * @info_mask_shared_by_type: What information is to be exported that is shared
183 * by all channels of the same type.
184 * @info_mask_shared_by_dir: What information is to be exported that is shared
185 * by all channels of the same direction.
186 * @info_mask_shared_by_all: What information is to be exported that is shared
188 * @event_mask: What events can this channel produce.
189 * @event_spec: Array of events which should be registered for this
191 * @num_event_specs: Size of the event_spec array.
192 * @ext_info: Array of extended info attributes for this channel.
193 * The array is NULL terminated, the last element should
194 * have its name field set to NULL.
195 * @extend_name: Allows labeling of channel attributes with an
196 * informative name. Note this has no effect codes etc,
198 * @datasheet_name: A name used in in-kernel mapping of channels. It should
199 * correspond to the first name that the channel is referred
200 * to by in the datasheet (e.g. IND), or the nearest
201 * possible compound name (e.g. IND-INC).
202 * @modified: Does a modifier apply to this channel. What these are
203 * depends on the channel type. Modifier is set in
204 * channel2. Examples are IIO_MOD_X for axial sensors about
206 * @indexed: Specify the channel has a numerical index. If not,
207 * the channel index number will be suppressed for sysfs
208 * attributes but not for event codes.
209 * @output: Channel is output.
210 * @differential: Channel is differential.
212 struct iio_chan_spec {
213 enum iio_chan_type type;
216 unsigned long address;
223 enum iio_endian endianness;
225 long info_mask_separate;
226 long info_mask_shared_by_type;
227 long info_mask_shared_by_dir;
228 long info_mask_shared_by_all;
230 const struct iio_event_spec *event_spec;
231 unsigned int num_event_specs;
232 const struct iio_chan_spec_ext_info *ext_info;
233 const char *extend_name;
234 const char *datasheet_name;
238 unsigned differential:1;
243 * iio_channel_has_info() - Checks whether a channel supports a info attribute
244 * @chan: The channel to be queried
245 * @type: Type of the info attribute to be checked
247 * Returns true if the channels supports reporting values for the given info
248 * attribute type, false otherwise.
250 static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
251 enum iio_chan_info_enum type)
253 return (chan->info_mask_separate & BIT(type)) |
254 (chan->info_mask_shared_by_type & BIT(type)) |
255 (chan->info_mask_shared_by_dir & BIT(type)) |
256 (chan->info_mask_shared_by_all & BIT(type));
259 #define IIO_ST(si, rb, sb, sh) \
260 { .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
262 #define IIO_CHAN_SOFT_TIMESTAMP(_si) \
263 { .type = IIO_TIMESTAMP, .channel = -1, \
264 .scan_index = _si, .scan_type = IIO_ST('s', 64, 64, 0) }
267 * iio_get_time_ns() - utility function to get a time stamp for events etc
269 static inline s64 iio_get_time_ns(void)
273 * calls getnstimeofday.
274 * If hrtimers then up to ns accurate, if not microsecond.
276 ktime_get_real_ts(&ts);
278 return timespec_to_ns(&ts);
281 /* Device operating modes */
282 #define INDIO_DIRECT_MODE 0x01
283 #define INDIO_BUFFER_TRIGGERED 0x02
284 #define INDIO_BUFFER_HARDWARE 0x08
286 #define INDIO_ALL_BUFFER_MODES \
287 (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE)
289 struct iio_trigger; /* forward declaration */
293 * struct iio_info - constant information about device
294 * @driver_module: module structure used to ensure correct
295 * ownership of chrdevs etc
296 * @event_attrs: event control attributes
297 * @attrs: general purpose device attributes
298 * @read_raw: function to request a value from the device.
299 * mask specifies which value. Note 0 means a reading of
300 * the channel in question. Return value will specify the
301 * type of value returned by the device. val and val2 will
302 * contain the elements making up the returned value.
303 * @write_raw: function to write a value to the device.
304 * Parameters are the same as for read_raw.
305 * @write_raw_get_fmt: callback function to query the expected
306 * format/precision. If not set by the driver, write_raw
307 * returns IIO_VAL_INT_PLUS_MICRO.
308 * @read_event_config: find out if the event is enabled.
309 * @write_event_config: set if the event is enabled.
310 * @read_event_value: read a value associated with the event. Meaning
311 * is event dependant. event_code specifies which event.
312 * @write_event_value: write the value associated with the event.
313 * Meaning is event dependent.
314 * @read_event_config_new: find out if the event is enabled. New style interface.
315 * @write_event_config_new: set if the event is enabled. New style interface.
316 * @read_event_value_new: read a configuration value associated with the event.
317 * New style interface.
318 * @write_event_value_new: write a configuration value for the event. New style
320 * @validate_trigger: function to validate the trigger when the
321 * current trigger gets changed.
322 * @update_scan_mode: function to configure device and scan buffer when
323 * channels have changed
324 * @debugfs_reg_access: function to read or write register value of device
327 struct module *driver_module;
328 struct attribute_group *event_attrs;
329 const struct attribute_group *attrs;
331 int (*read_raw)(struct iio_dev *indio_dev,
332 struct iio_chan_spec const *chan,
337 int (*write_raw)(struct iio_dev *indio_dev,
338 struct iio_chan_spec const *chan,
343 int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
344 struct iio_chan_spec const *chan,
347 int (*read_event_config)(struct iio_dev *indio_dev,
350 int (*write_event_config)(struct iio_dev *indio_dev,
354 int (*read_event_value)(struct iio_dev *indio_dev,
357 int (*write_event_value)(struct iio_dev *indio_dev,
361 int (*read_event_config_new)(struct iio_dev *indio_dev,
362 const struct iio_chan_spec *chan,
363 enum iio_event_type type,
364 enum iio_event_direction dir);
366 int (*write_event_config_new)(struct iio_dev *indio_dev,
367 const struct iio_chan_spec *chan,
368 enum iio_event_type type,
369 enum iio_event_direction dir,
372 int (*read_event_value_new)(struct iio_dev *indio_dev,
373 const struct iio_chan_spec *chan,
374 enum iio_event_type type,
375 enum iio_event_direction dir,
376 enum iio_event_info info, int *val, int *val2);
378 int (*write_event_value_new)(struct iio_dev *indio_dev,
379 const struct iio_chan_spec *chan,
380 enum iio_event_type type,
381 enum iio_event_direction dir,
382 enum iio_event_info info, int val, int val2);
384 int (*validate_trigger)(struct iio_dev *indio_dev,
385 struct iio_trigger *trig);
386 int (*update_scan_mode)(struct iio_dev *indio_dev,
387 const unsigned long *scan_mask);
388 int (*debugfs_reg_access)(struct iio_dev *indio_dev,
389 unsigned reg, unsigned writeval,
394 * struct iio_buffer_setup_ops - buffer setup related callbacks
395 * @preenable: [DRIVER] function to run prior to marking buffer enabled
396 * @postenable: [DRIVER] function to run after marking buffer enabled
397 * @predisable: [DRIVER] function to run prior to marking buffer
399 * @postdisable: [DRIVER] function to run after marking buffer disabled
400 * @validate_scan_mask: [DRIVER] function callback to check whether a given
401 * scan mask is valid for the device.
403 struct iio_buffer_setup_ops {
404 int (*preenable)(struct iio_dev *);
405 int (*postenable)(struct iio_dev *);
406 int (*predisable)(struct iio_dev *);
407 int (*postdisable)(struct iio_dev *);
408 bool (*validate_scan_mask)(struct iio_dev *indio_dev,
409 const unsigned long *scan_mask);
413 * struct iio_dev - industrial I/O device
414 * @id: [INTERN] used to identify device internally
415 * @modes: [DRIVER] operating modes supported by device
416 * @currentmode: [DRIVER] current operating mode
417 * @dev: [DRIVER] device structure, should be assigned a parent
419 * @event_interface: [INTERN] event chrdevs associated with interrupt lines
420 * @buffer: [DRIVER] any buffer present
421 * @buffer_list: [INTERN] list of all buffers currently attached
422 * @scan_bytes: [INTERN] num bytes captured to be fed to buffer demux
423 * @mlock: [INTERN] lock used to prevent simultaneous device state
425 * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
426 * @masklength: [INTERN] the length of the mask established from
428 * @active_scan_mask: [INTERN] union of all scan masks requested by buffers
429 * @scan_timestamp: [INTERN] set if any buffers have requested timestamp
430 * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
431 * @trig: [INTERN] current device trigger (buffer modes)
432 * @pollfunc: [DRIVER] function run on trigger being received
433 * @channels: [DRIVER] channel specification structure table
434 * @num_channels: [DRIVER] number of channels specified in @channels.
435 * @channel_attr_list: [INTERN] keep track of automatically created channel
437 * @chan_attr_group: [INTERN] group for all attrs in base directory
438 * @name: [DRIVER] name of the device.
439 * @info: [DRIVER] callbacks and constant info from driver
440 * @info_exist_lock: [INTERN] lock to prevent use during removal
441 * @setup_ops: [DRIVER] callbacks to call before and after buffer
443 * @chrdev: [INTERN] associated character device
444 * @groups: [INTERN] attribute groups
445 * @groupcounter: [INTERN] index of next attribute group
446 * @flags: [INTERN] file ops related flags including busy flag.
447 * @debugfs_dentry: [INTERN] device specific debugfs dentry.
448 * @cached_reg_addr: [INTERN] cached register address for debugfs reads.
457 struct iio_event_interface *event_interface;
459 struct iio_buffer *buffer;
460 struct list_head buffer_list;
464 const unsigned long *available_scan_masks;
466 const unsigned long *active_scan_mask;
468 unsigned scan_index_timestamp;
469 struct iio_trigger *trig;
470 struct iio_poll_func *pollfunc;
472 struct iio_chan_spec const *channels;
475 struct list_head channel_attr_list;
476 struct attribute_group chan_attr_group;
478 const struct iio_info *info;
479 struct mutex info_exist_lock;
480 const struct iio_buffer_setup_ops *setup_ops;
482 #define IIO_MAX_GROUPS 6
483 const struct attribute_group *groups[IIO_MAX_GROUPS + 1];
487 #if defined(CONFIG_DEBUG_FS)
488 struct dentry *debugfs_dentry;
489 unsigned cached_reg_addr;
494 * iio_find_channel_from_si() - get channel from its scan index
496 * @si: scan index to match
498 const struct iio_chan_spec
499 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
502 * iio_device_register() - register a device with the IIO subsystem
503 * @indio_dev: Device structure filled by the device driver
505 int iio_device_register(struct iio_dev *indio_dev);
508 * iio_device_unregister() - unregister a device from the IIO subsystem
509 * @indio_dev: Device structure representing the device.
511 void iio_device_unregister(struct iio_dev *indio_dev);
514 * iio_push_event() - try to add event to the list for userspace reading
515 * @indio_dev: IIO device structure
516 * @ev_code: What event
517 * @timestamp: When the event occurred
519 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
521 extern struct bus_type iio_bus_type;
524 * iio_device_put() - reference counted deallocation of struct device
525 * @indio_dev: IIO device structure containing the device
527 static inline void iio_device_put(struct iio_dev *indio_dev)
530 put_device(&indio_dev->dev);
534 * dev_to_iio_dev() - Get IIO device struct from a device struct
535 * @dev: The device embedded in the IIO device
537 * Note: The device must be a IIO device, otherwise the result is undefined.
539 static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
541 return container_of(dev, struct iio_dev, dev);
545 * iio_device_get() - increment reference count for the device
546 * @indio_dev: IIO device structure
548 * Returns: The passed IIO device
550 static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
552 return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
557 * iio_device_set_drvdata() - Set device driver data
558 * @indio_dev: IIO device structure
559 * @data: Driver specific data
561 * Allows to attach an arbitrary pointer to an IIO device, which can later be
562 * retrieved by iio_device_get_drvdata().
564 static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
566 dev_set_drvdata(&indio_dev->dev, data);
570 * iio_device_get_drvdata() - Get device driver data
571 * @indio_dev: IIO device structure
573 * Returns the data previously set with iio_device_set_drvdata()
575 static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev)
577 return dev_get_drvdata(&indio_dev->dev);
580 /* Can we make this smaller? */
581 #define IIO_ALIGN L1_CACHE_BYTES
583 * iio_device_alloc() - allocate an iio_dev from a driver
584 * @sizeof_priv: Space to allocate for private structure.
586 struct iio_dev *iio_device_alloc(int sizeof_priv);
588 static inline void *iio_priv(const struct iio_dev *indio_dev)
590 return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
593 static inline struct iio_dev *iio_priv_to_dev(void *priv)
595 return (struct iio_dev *)((char *)priv -
596 ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
600 * iio_device_free() - free an iio_dev from a driver
601 * @indio_dev: the iio_dev associated with the device
603 void iio_device_free(struct iio_dev *indio_dev);
606 * devm_iio_device_alloc - Resource-managed iio_device_alloc()
607 * @dev: Device to allocate iio_dev for
608 * @sizeof_priv: Space to allocate for private structure.
610 * Managed iio_device_alloc. iio_dev allocated with this function is
611 * automatically freed on driver detach.
613 * If an iio_dev allocated with this function needs to be freed separately,
614 * devm_iio_device_free() must be used.
617 * Pointer to allocated iio_dev on success, NULL on failure.
619 struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv);
622 * devm_iio_device_free - Resource-managed iio_device_free()
623 * @dev: Device this iio_dev belongs to
624 * @indio_dev: the iio_dev associated with the device
626 * Free iio_dev allocated with devm_iio_device_alloc().
628 void devm_iio_device_free(struct device *dev, struct iio_dev *indio_dev);
631 * devm_iio_trigger_alloc - Resource-managed iio_trigger_alloc()
632 * @dev: Device to allocate iio_trigger for
633 * @fmt: trigger name format. If it includes format
634 * specifiers, the additional arguments following
635 * format are formatted and inserted in the resulting
636 * string replacing their respective specifiers.
638 * Managed iio_trigger_alloc. iio_trigger allocated with this function is
639 * automatically freed on driver detach.
641 * If an iio_trigger allocated with this function needs to be freed separately,
642 * devm_iio_trigger_free() must be used.
645 * Pointer to allocated iio_trigger on success, NULL on failure.
647 struct iio_trigger *devm_iio_trigger_alloc(struct device *dev,
648 const char *fmt, ...);
651 * devm_iio_trigger_free - Resource-managed iio_trigger_free()
652 * @dev: Device this iio_dev belongs to
653 * @iio_trig: the iio_trigger associated with the device
655 * Free iio_trigger allocated with devm_iio_trigger_alloc().
657 void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig);
660 * iio_buffer_enabled() - helper function to test if the buffer is enabled
661 * @indio_dev: IIO device structure for device
663 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
665 return indio_dev->currentmode
666 & (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE);
670 * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
671 * @indio_dev: IIO device structure for device
673 #if defined(CONFIG_DEBUG_FS)
674 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
676 return indio_dev->debugfs_dentry;
679 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
685 int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
689 * IIO_DEGREE_TO_RAD() - Convert degree to rad
690 * @deg: A value in degree
692 * Returns the given value converted from degree to rad
694 #define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
697 * IIO_G_TO_M_S_2() - Convert g to meter / second**2
700 * Returns the given value converted from g to meter / second**2
702 #define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
704 #endif /* _INDUSTRIAL_IO_H_ */