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,
40 #define IIO_CHAN_INFO_SHARED_BIT(type) BIT(type*2)
41 #define IIO_CHAN_INFO_SEPARATE_BIT(type) BIT(type*2 + 1)
43 #define IIO_CHAN_INFO_RAW_SEPARATE_BIT \
44 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_RAW)
45 #define IIO_CHAN_INFO_PROCESSED_SEPARATE_BIT \
46 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PROCESSED)
47 #define IIO_CHAN_INFO_SCALE_SEPARATE_BIT \
48 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SCALE)
49 #define IIO_CHAN_INFO_SCALE_SHARED_BIT \
50 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SCALE)
51 #define IIO_CHAN_INFO_OFFSET_SEPARATE_BIT \
52 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_OFFSET)
53 #define IIO_CHAN_INFO_OFFSET_SHARED_BIT \
54 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_OFFSET)
55 #define IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT \
56 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBSCALE)
57 #define IIO_CHAN_INFO_CALIBSCALE_SHARED_BIT \
58 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_CALIBSCALE)
59 #define IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT \
60 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBBIAS)
61 #define IIO_CHAN_INFO_CALIBBIAS_SHARED_BIT \
62 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_CALIBBIAS)
63 #define IIO_CHAN_INFO_PEAK_SEPARATE_BIT \
64 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PEAK)
65 #define IIO_CHAN_INFO_PEAK_SHARED_BIT \
66 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PEAK)
67 #define IIO_CHAN_INFO_PEAKSCALE_SEPARATE_BIT \
68 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PEAKSCALE)
69 #define IIO_CHAN_INFO_PEAKSCALE_SHARED_BIT \
70 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PEAKSCALE)
71 #define IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SEPARATE_BIT \
72 IIO_CHAN_INFO_SEPARATE_BIT( \
73 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW)
74 #define IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SHARED_BIT \
75 IIO_CHAN_INFO_SHARED_BIT( \
76 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW)
77 #define IIO_CHAN_INFO_AVERAGE_RAW_SEPARATE_BIT \
78 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_AVERAGE_RAW)
79 #define IIO_CHAN_INFO_AVERAGE_RAW_SHARED_BIT \
80 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_AVERAGE_RAW)
81 #define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SHARED_BIT \
82 IIO_CHAN_INFO_SHARED_BIT( \
83 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)
84 #define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT \
85 IIO_CHAN_INFO_SEPARATE_BIT( \
86 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)
87 #define IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT \
88 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SAMP_FREQ)
89 #define IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT \
90 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SAMP_FREQ)
91 #define IIO_CHAN_INFO_FREQUENCY_SEPARATE_BIT \
92 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_FREQUENCY)
93 #define IIO_CHAN_INFO_FREQUENCY_SHARED_BIT \
94 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_FREQUENCY)
95 #define IIO_CHAN_INFO_PHASE_SEPARATE_BIT \
96 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PHASE)
97 #define IIO_CHAN_INFO_PHASE_SHARED_BIT \
98 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PHASE)
99 #define IIO_CHAN_INFO_HARDWAREGAIN_SEPARATE_BIT \
100 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_HARDWAREGAIN)
101 #define IIO_CHAN_INFO_HARDWAREGAIN_SHARED_BIT \
102 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_HARDWAREGAIN)
110 struct iio_chan_spec;
114 * struct iio_chan_spec_ext_info - Extended channel info attribute
115 * @name: Info attribute name
116 * @shared: Whether this attribute is shared between all channels.
117 * @read: Read callback for this info attribute, may be NULL.
118 * @write: Write callback for this info attribute, may be NULL.
119 * @private: Data private to the driver.
121 struct iio_chan_spec_ext_info {
124 ssize_t (*read)(struct iio_dev *, uintptr_t private,
125 struct iio_chan_spec const *, char *buf);
126 ssize_t (*write)(struct iio_dev *, uintptr_t private,
127 struct iio_chan_spec const *, const char *buf,
133 * struct iio_enum - Enum channel info attribute
134 * @items: An array of strings.
135 * @num_items: Length of the item array.
136 * @set: Set callback function, may be NULL.
137 * @get: Get callback function, may be NULL.
139 * The iio_enum struct can be used to implement enum style channel attributes.
140 * Enum style attributes are those which have a set of strings which map to
141 * unsigned integer values. The IIO enum helper code takes care of mapping
142 * between value and string as well as generating a "_available" file which
143 * contains a list of all available items. The set callback will be called when
144 * the attribute is updated. The last parameter is the index to the newly
145 * activated item. The get callback will be used to query the currently active
146 * item and is supposed to return the index for it.
149 const char * const *items;
150 unsigned int num_items;
151 int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
152 int (*get)(struct iio_dev *, const struct iio_chan_spec *);
155 ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
156 uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
157 ssize_t iio_enum_read(struct iio_dev *indio_dev,
158 uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
159 ssize_t iio_enum_write(struct iio_dev *indio_dev,
160 uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
164 * IIO_ENUM() - Initialize enum extended channel attribute
165 * @_name: Attribute name
166 * @_shared: Whether the attribute is shared between all channels
167 * @_e: Pointer to a iio_enum struct
169 * This should usually be used together with IIO_ENUM_AVAILABLE()
171 #define IIO_ENUM(_name, _shared, _e) \
174 .shared = (_shared), \
175 .read = iio_enum_read, \
176 .write = iio_enum_write, \
177 .private = (uintptr_t)(_e), \
181 * IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
182 * @_name: Attribute name ("_available" will be appended to the name)
183 * @_e: Pointer to a iio_enum struct
185 * Creates a read only attribute which list all the available enum items in a
186 * space separated list. This should usually be used together with IIO_ENUM()
188 #define IIO_ENUM_AVAILABLE(_name, _e) \
190 .name = (_name "_available"), \
192 .read = iio_enum_available_read, \
193 .private = (uintptr_t)(_e), \
197 * struct iio_chan_spec - specification of a single channel
198 * @type: What type of measurement is the channel making.
199 * @channel: What number do we wish to assign the channel.
200 * @channel2: If there is a second number for a differential
201 * channel then this is it. If modified is set then the
202 * value here specifies the modifier.
203 * @address: Driver specific identifier.
204 * @scan_index: Monotonic index to give ordering in scans when read
206 * @scan_type: Sign: 's' or 'u' to specify signed or unsigned
207 * realbits: Number of valid bits of data
208 * storage_bits: Realbits + padding
209 * shift: Shift right by this before masking out
211 * endianness: little or big endian
212 * @info_mask: What information is to be exported about this channel.
213 * This includes calibbias, scale etc.
214 * @event_mask: What events can this channel produce.
215 * @ext_info: Array of extended info attributes for this channel.
216 * The array is NULL terminated, the last element should
217 * have its name field set to NULL.
218 * @extend_name: Allows labeling of channel attributes with an
219 * informative name. Note this has no effect codes etc,
221 * @datasheet_name: A name used in in-kernel mapping of channels. It should
222 * correspond to the first name that the channel is referred
223 * to by in the datasheet (e.g. IND), or the nearest
224 * possible compound name (e.g. IND-INC).
225 * @modified: Does a modifier apply to this channel. What these are
226 * depends on the channel type. Modifier is set in
227 * channel2. Examples are IIO_MOD_X for axial sensors about
229 * @indexed: Specify the channel has a numerical index. If not,
230 * the channel index number will be suppressed for sysfs
231 * attributes but not for event codes.
232 * @differential: Channel is differential.
234 struct iio_chan_spec {
235 enum iio_chan_type type;
238 unsigned long address;
245 enum iio_endian endianness;
249 const struct iio_chan_spec_ext_info *ext_info;
250 const char *extend_name;
251 const char *datasheet_name;
255 unsigned differential:1;
258 #define IIO_ST(si, rb, sb, sh) \
259 { .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
261 #define IIO_CHAN_SOFT_TIMESTAMP(_si) \
262 { .type = IIO_TIMESTAMP, .channel = -1, \
263 .scan_index = _si, .scan_type = IIO_ST('s', 64, 64, 0) }
266 * iio_get_time_ns() - utility function to get a time stamp for events etc
268 static inline s64 iio_get_time_ns(void)
272 * calls getnstimeofday.
273 * If hrtimers then up to ns accurate, if not microsecond.
275 ktime_get_real_ts(&ts);
277 return timespec_to_ns(&ts);
280 /* Device operating modes */
281 #define INDIO_DIRECT_MODE 0x01
282 #define INDIO_BUFFER_TRIGGERED 0x02
283 #define INDIO_BUFFER_HARDWARE 0x08
285 #define INDIO_ALL_BUFFER_MODES \
286 (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE)
288 struct iio_trigger; /* forward declaration */
292 * struct iio_info - constant information about device
293 * @driver_module: module structure used to ensure correct
294 * ownership of chrdevs etc
295 * @event_attrs: event control attributes
296 * @attrs: general purpose device attributes
297 * @read_raw: function to request a value from the device.
298 * mask specifies which value. Note 0 means a reading of
299 * the channel in question. Return value will specify the
300 * type of value returned by the device. val and val2 will
301 * contain the elements making up the returned value.
302 * @write_raw: function to write a value to the device.
303 * Parameters are the same as for read_raw.
304 * @write_raw_get_fmt: callback function to query the expected
305 * format/precision. If not set by the driver, write_raw
306 * returns IIO_VAL_INT_PLUS_MICRO.
307 * @read_event_config: find out if the event is enabled.
308 * @write_event_config: set if the event is enabled.
309 * @read_event_value: read a value associated with the event. Meaning
310 * is event dependant. event_code specifies which event.
311 * @write_event_value: write the value associated with the event.
312 * Meaning is event dependent.
313 * @validate_trigger: function to validate the trigger when the
314 * current trigger gets changed.
317 struct module *driver_module;
318 struct attribute_group *event_attrs;
319 const struct attribute_group *attrs;
321 int (*read_raw)(struct iio_dev *indio_dev,
322 struct iio_chan_spec const *chan,
327 int (*write_raw)(struct iio_dev *indio_dev,
328 struct iio_chan_spec const *chan,
333 int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
334 struct iio_chan_spec const *chan,
337 int (*read_event_config)(struct iio_dev *indio_dev,
340 int (*write_event_config)(struct iio_dev *indio_dev,
344 int (*read_event_value)(struct iio_dev *indio_dev,
347 int (*write_event_value)(struct iio_dev *indio_dev,
350 int (*validate_trigger)(struct iio_dev *indio_dev,
351 struct iio_trigger *trig);
352 int (*update_scan_mode)(struct iio_dev *indio_dev,
353 const unsigned long *scan_mask);
354 int (*debugfs_reg_access)(struct iio_dev *indio_dev,
355 unsigned reg, unsigned writeval,
360 * struct iio_buffer_setup_ops - buffer setup related callbacks
361 * @preenable: [DRIVER] function to run prior to marking buffer enabled
362 * @postenable: [DRIVER] function to run after marking buffer enabled
363 * @predisable: [DRIVER] function to run prior to marking buffer
365 * @postdisable: [DRIVER] function to run after marking buffer disabled
366 * @validate_scan_mask: [DRIVER] function callback to check whether a given
367 * scan mask is valid for the device.
369 struct iio_buffer_setup_ops {
370 int (*preenable)(struct iio_dev *);
371 int (*postenable)(struct iio_dev *);
372 int (*predisable)(struct iio_dev *);
373 int (*postdisable)(struct iio_dev *);
374 bool (*validate_scan_mask)(struct iio_dev *indio_dev,
375 const unsigned long *scan_mask);
379 * struct iio_dev - industrial I/O device
380 * @id: [INTERN] used to identify device internally
381 * @modes: [DRIVER] operating modes supported by device
382 * @currentmode: [DRIVER] current operating mode
383 * @dev: [DRIVER] device structure, should be assigned a parent
385 * @event_interface: [INTERN] event chrdevs associated with interrupt lines
386 * @buffer: [DRIVER] any buffer present
387 * @scan_bytes: [INTERN] num bytes captured to be fed to buffer demux
388 * @mlock: [INTERN] lock used to prevent simultaneous device state
390 * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
391 * @masklength: [INTERN] the length of the mask established from
393 * @active_scan_mask: [INTERN] union of all scan masks requested by buffers
394 * @scan_timestamp: [INTERN] set if any buffers have requested timestamp
395 * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
396 * @trig: [INTERN] current device trigger (buffer modes)
397 * @pollfunc: [DRIVER] function run on trigger being received
398 * @channels: [DRIVER] channel specification structure table
399 * @num_channels: [DRIVER] number of channels specified in @channels.
400 * @channel_attr_list: [INTERN] keep track of automatically created channel
402 * @chan_attr_group: [INTERN] group for all attrs in base directory
403 * @name: [DRIVER] name of the device.
404 * @info: [DRIVER] callbacks and constant info from driver
405 * @info_exist_lock: [INTERN] lock to prevent use during removal
406 * @setup_ops: [DRIVER] callbacks to call before and after buffer
408 * @chrdev: [INTERN] associated character device
409 * @groups: [INTERN] attribute groups
410 * @groupcounter: [INTERN] index of next attribute group
411 * @flags: [INTERN] file ops related flags including busy flag.
412 * @debugfs_dentry: [INTERN] device specific debugfs dentry.
413 * @cached_reg_addr: [INTERN] cached register address for debugfs reads.
422 struct iio_event_interface *event_interface;
424 struct iio_buffer *buffer;
428 const unsigned long *available_scan_masks;
430 const unsigned long *active_scan_mask;
432 unsigned scan_index_timestamp;
433 struct iio_trigger *trig;
434 struct iio_poll_func *pollfunc;
436 struct iio_chan_spec const *channels;
439 struct list_head channel_attr_list;
440 struct attribute_group chan_attr_group;
442 const struct iio_info *info;
443 struct mutex info_exist_lock;
444 const struct iio_buffer_setup_ops *setup_ops;
446 #define IIO_MAX_GROUPS 6
447 const struct attribute_group *groups[IIO_MAX_GROUPS + 1];
451 #if defined(CONFIG_DEBUG_FS)
452 struct dentry *debugfs_dentry;
453 unsigned cached_reg_addr;
458 * iio_find_channel_from_si() - get channel from its scan index
460 * @si: scan index to match
462 const struct iio_chan_spec
463 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
466 * iio_device_register() - register a device with the IIO subsystem
467 * @indio_dev: Device structure filled by the device driver
469 int iio_device_register(struct iio_dev *indio_dev);
472 * iio_device_unregister() - unregister a device from the IIO subsystem
473 * @indio_dev: Device structure representing the device.
475 void iio_device_unregister(struct iio_dev *indio_dev);
478 * iio_push_event() - try to add event to the list for userspace reading
479 * @indio_dev: IIO device structure
480 * @ev_code: What event
481 * @timestamp: When the event occurred
483 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
485 extern struct bus_type iio_bus_type;
488 * iio_device_put() - reference counted deallocation of struct device
489 * @indio_dev: IIO device structure containing the device
491 static inline void iio_device_put(struct iio_dev *indio_dev)
494 put_device(&indio_dev->dev);
498 * dev_to_iio_dev() - Get IIO device struct from a device struct
499 * @dev: The device embedded in the IIO device
501 * Note: The device must be a IIO device, otherwise the result is undefined.
503 static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
505 return container_of(dev, struct iio_dev, dev);
509 * iio_device_get() - increment reference count for the device
510 * @indio_dev: IIO device structure
512 * Returns: The passed IIO device
514 static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
516 return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
519 /* Can we make this smaller? */
520 #define IIO_ALIGN L1_CACHE_BYTES
522 * iio_device_alloc() - allocate an iio_dev from a driver
523 * @sizeof_priv: Space to allocate for private structure.
525 struct iio_dev *iio_device_alloc(int sizeof_priv);
527 static inline void *iio_priv(const struct iio_dev *indio_dev)
529 return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
532 static inline struct iio_dev *iio_priv_to_dev(void *priv)
534 return (struct iio_dev *)((char *)priv -
535 ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
539 * iio_device_free() - free an iio_dev from a driver
540 * @indio_dev: the iio_dev associated with the device
542 void iio_device_free(struct iio_dev *indio_dev);
545 * iio_buffer_enabled() - helper function to test if the buffer is enabled
546 * @indio_dev: IIO device structure for device
548 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
550 return indio_dev->currentmode
551 & (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE);
555 * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
556 * @indio_dev: IIO device structure for device
558 #if defined(CONFIG_DEBUG_FS)
559 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
561 return indio_dev->debugfs_dentry;
564 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
570 #endif /* _INDUSTRIAL_IO_H_ */