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,
37 #define IIO_CHAN_INFO_SHARED_BIT(type) BIT(type*2)
38 #define IIO_CHAN_INFO_SEPARATE_BIT(type) BIT(type*2 + 1)
40 #define IIO_CHAN_INFO_RAW_SEPARATE_BIT \
41 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_RAW)
42 #define IIO_CHAN_INFO_PROCESSED_SEPARATE_BIT \
43 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PROCESSED)
44 #define IIO_CHAN_INFO_SCALE_SEPARATE_BIT \
45 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SCALE)
46 #define IIO_CHAN_INFO_SCALE_SHARED_BIT \
47 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SCALE)
48 #define IIO_CHAN_INFO_OFFSET_SEPARATE_BIT \
49 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_OFFSET)
50 #define IIO_CHAN_INFO_OFFSET_SHARED_BIT \
51 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_OFFSET)
52 #define IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT \
53 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBSCALE)
54 #define IIO_CHAN_INFO_CALIBSCALE_SHARED_BIT \
55 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_CALIBSCALE)
56 #define IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT \
57 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBBIAS)
58 #define IIO_CHAN_INFO_CALIBBIAS_SHARED_BIT \
59 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_CALIBBIAS)
60 #define IIO_CHAN_INFO_PEAK_SEPARATE_BIT \
61 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PEAK)
62 #define IIO_CHAN_INFO_PEAK_SHARED_BIT \
63 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PEAK)
64 #define IIO_CHAN_INFO_PEAKSCALE_SEPARATE_BIT \
65 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PEAKSCALE)
66 #define IIO_CHAN_INFO_PEAKSCALE_SHARED_BIT \
67 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PEAKSCALE)
68 #define IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SEPARATE_BIT \
69 IIO_CHAN_INFO_SEPARATE_BIT( \
70 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW)
71 #define IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SHARED_BIT \
72 IIO_CHAN_INFO_SHARED_BIT( \
73 IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW)
74 #define IIO_CHAN_INFO_AVERAGE_RAW_SEPARATE_BIT \
75 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_AVERAGE_RAW)
76 #define IIO_CHAN_INFO_AVERAGE_RAW_SHARED_BIT \
77 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_AVERAGE_RAW)
78 #define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SHARED_BIT \
79 IIO_CHAN_INFO_SHARED_BIT( \
80 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)
81 #define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT \
82 IIO_CHAN_INFO_SEPARATE_BIT( \
83 IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)
84 #define IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT \
85 IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SAMP_FREQ)
86 #define IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT \
87 IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SAMP_FREQ)
99 * struct iio_chan_spec_ext_info - Extended channel info attribute
100 * @name: Info attribute name
101 * @shared: Whether this attribute is shared between all channels.
102 * @read: Read callback for this info attribute, may be NULL.
103 * @write: Write callback for this info attribute, may be NULL.
105 struct iio_chan_spec_ext_info {
108 ssize_t (*read)(struct iio_dev *, struct iio_chan_spec const *,
110 ssize_t (*write)(struct iio_dev *, struct iio_chan_spec const *,
111 const char *buf, size_t len);
115 * struct iio_chan_spec - specification of a single channel
116 * @type: What type of measurement is the channel making.
117 * @channel: What number or name do we wish to assign the channel.
118 * @channel2: If there is a second number for a differential
119 * channel then this is it. If modified is set then the
120 * value here specifies the modifier.
121 * @address: Driver specific identifier.
122 * @scan_index: Monotonic index to give ordering in scans when read
124 * @scan_type: Sign: 's' or 'u' to specify signed or unsigned
125 * realbits: Number of valid bits of data
126 * storage_bits: Realbits + padding
127 * shift: Shift right by this before masking out
129 * endianness: little or big endian
130 * @info_mask: What information is to be exported about this channel.
131 * This includes calibbias, scale etc.
132 * @event_mask: What events can this channel produce.
133 * @ext_info: Array of extended info attributes for this channel.
134 * The array is NULL terminated, the last element should
135 * have it's name field set to NULL.
136 * @extend_name: Allows labeling of channel attributes with an
137 * informative name. Note this has no effect codes etc,
139 * @datasheet_name: A name used in in kernel mapping of channels. It should
140 * correspond to the first name that the channel is referred
141 * to by in the datasheet (e.g. IND), or the nearest
142 * possible compound name (e.g. IND-INC).
143 * @modified: Does a modifier apply to this channel. What these are
144 * depends on the channel type. Modifier is set in
145 * channel2. Examples are IIO_MOD_X for axial sensors about
147 * @indexed: Specify the channel has a numerical index. If not,
148 * the value in channel will be suppressed for attribute
149 * but not for event codes. Typically set it to 0 when
150 * the index is false.
151 * @differential: Channel is differential.
153 struct iio_chan_spec {
154 enum iio_chan_type type;
157 unsigned long address;
164 enum iio_endian endianness;
168 const struct iio_chan_spec_ext_info *ext_info;
169 const char *extend_name;
170 const char *datasheet_name;
174 unsigned differential:1;
177 #define IIO_ST(si, rb, sb, sh) \
178 { .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
180 #define IIO_CHAN_SOFT_TIMESTAMP(_si) \
181 { .type = IIO_TIMESTAMP, .channel = -1, \
182 .scan_index = _si, .scan_type = IIO_ST('s', 64, 64, 0) }
185 * iio_get_time_ns() - utility function to get a time stamp for events etc
187 static inline s64 iio_get_time_ns(void)
191 * calls getnstimeofday.
192 * If hrtimers then up to ns accurate, if not microsecond.
194 ktime_get_real_ts(&ts);
196 return timespec_to_ns(&ts);
199 /* Device operating modes */
200 #define INDIO_DIRECT_MODE 0x01
201 #define INDIO_BUFFER_TRIGGERED 0x02
202 #define INDIO_BUFFER_HARDWARE 0x08
204 #define INDIO_ALL_BUFFER_MODES \
205 (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE)
207 struct iio_trigger; /* forward declaration */
211 * struct iio_info - constant information about device
212 * @driver_module: module structure used to ensure correct
213 * ownership of chrdevs etc
214 * @event_attrs: event control attributes
215 * @attrs: general purpose device attributes
216 * @read_raw: function to request a value from the device.
217 * mask specifies which value. Note 0 means a reading of
218 * the channel in question. Return value will specify the
219 * type of value returned by the device. val and val2 will
220 * contain the elements making up the returned value.
221 * @write_raw: function to write a value to the device.
222 * Parameters are the same as for read_raw.
223 * @write_raw_get_fmt: callback function to query the expected
224 * format/precision. If not set by the driver, write_raw
225 * returns IIO_VAL_INT_PLUS_MICRO.
226 * @read_event_config: find out if the event is enabled.
227 * @write_event_config: set if the event is enabled.
228 * @read_event_value: read a value associated with the event. Meaning
229 * is event dependant. event_code specifies which event.
230 * @write_event_value: write the value associated with the event.
231 * Meaning is event dependent.
232 * @validate_trigger: function to validate the trigger when the
233 * current trigger gets changed.
236 struct module *driver_module;
237 struct attribute_group *event_attrs;
238 const struct attribute_group *attrs;
240 int (*read_raw)(struct iio_dev *indio_dev,
241 struct iio_chan_spec const *chan,
246 int (*write_raw)(struct iio_dev *indio_dev,
247 struct iio_chan_spec const *chan,
252 int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
253 struct iio_chan_spec const *chan,
256 int (*read_event_config)(struct iio_dev *indio_dev,
259 int (*write_event_config)(struct iio_dev *indio_dev,
263 int (*read_event_value)(struct iio_dev *indio_dev,
266 int (*write_event_value)(struct iio_dev *indio_dev,
269 int (*validate_trigger)(struct iio_dev *indio_dev,
270 struct iio_trigger *trig);
271 int (*update_scan_mode)(struct iio_dev *indio_dev,
272 const unsigned long *scan_mask);
273 int (*debugfs_reg_access)(struct iio_dev *indio_dev,
274 unsigned reg, unsigned writeval,
279 * struct iio_buffer_setup_ops - buffer setup related callbacks
280 * @preenable: [DRIVER] function to run prior to marking buffer enabled
281 * @postenable: [DRIVER] function to run after marking buffer enabled
282 * @predisable: [DRIVER] function to run prior to marking buffer
284 * @postdisable: [DRIVER] function to run after marking buffer disabled
286 struct iio_buffer_setup_ops {
287 int (*preenable)(struct iio_dev *);
288 int (*postenable)(struct iio_dev *);
289 int (*predisable)(struct iio_dev *);
290 int (*postdisable)(struct iio_dev *);
294 * struct iio_dev - industrial I/O device
295 * @id: [INTERN] used to identify device internally
296 * @modes: [DRIVER] operating modes supported by device
297 * @currentmode: [DRIVER] current operating mode
298 * @dev: [DRIVER] device structure, should be assigned a parent
300 * @event_interface: [INTERN] event chrdevs associated with interrupt lines
301 * @buffer: [DRIVER] any buffer present
302 * @scan_bytes: [INTERN] num bytes captured to be fed to buffer demux
303 * @mlock: [INTERN] lock used to prevent simultaneous device state
305 * @available_scan_masks: [DRIVER] optional array of allowed bitmasks
306 * @masklength: [INTERN] the length of the mask established from
308 * @active_scan_mask: [INTERN] union of all scan masks requested by buffers
309 * @scan_timestamp: [INTERN] set if any buffers have requested timestamp
310 * @scan_index_timestamp:[INTERN] cache of the index to the timestamp
311 * @trig: [INTERN] current device trigger (buffer modes)
312 * @pollfunc: [DRIVER] function run on trigger being received
313 * @channels: [DRIVER] channel specification structure table
314 * @num_channels: [DRIVER] number of chanels specified in @channels.
315 * @channel_attr_list: [INTERN] keep track of automatically created channel
317 * @chan_attr_group: [INTERN] group for all attrs in base directory
318 * @name: [DRIVER] name of the device.
319 * @info: [DRIVER] callbacks and constant info from driver
320 * @info_exist_lock: [INTERN] lock to prevent use during removal
321 * @setup_ops: [DRIVER] callbacks to call before and after buffer
323 * @chrdev: [INTERN] associated character device
324 * @groups: [INTERN] attribute groups
325 * @groupcounter: [INTERN] index of next attribute group
326 * @flags: [INTERN] file ops related flags including busy flag.
327 * @debugfs_dentry: [INTERN] device specific debugfs dentry.
328 * @cached_reg_addr: [INTERN] cached register address for debugfs reads.
337 struct iio_event_interface *event_interface;
339 struct iio_buffer *buffer;
343 const unsigned long *available_scan_masks;
345 const unsigned long *active_scan_mask;
347 unsigned scan_index_timestamp;
348 struct iio_trigger *trig;
349 struct iio_poll_func *pollfunc;
351 struct iio_chan_spec const *channels;
354 struct list_head channel_attr_list;
355 struct attribute_group chan_attr_group;
357 const struct iio_info *info;
358 struct mutex info_exist_lock;
359 const struct iio_buffer_setup_ops *setup_ops;
361 #define IIO_MAX_GROUPS 6
362 const struct attribute_group *groups[IIO_MAX_GROUPS + 1];
366 #if defined(CONFIG_DEBUG_FS)
367 struct dentry *debugfs_dentry;
368 unsigned cached_reg_addr;
373 * iio_find_channel_from_si() - get channel from its scan index
375 * @si: scan index to match
377 const struct iio_chan_spec
378 *iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
381 * iio_device_register() - register a device with the IIO subsystem
382 * @indio_dev: Device structure filled by the device driver
384 int iio_device_register(struct iio_dev *indio_dev);
387 * iio_device_unregister() - unregister a device from the IIO subsystem
388 * @indio_dev: Device structure representing the device.
390 void iio_device_unregister(struct iio_dev *indio_dev);
393 * iio_push_event() - try to add event to the list for userspace reading
394 * @indio_dev: IIO device structure
395 * @ev_code: What event
396 * @timestamp: When the event occurred
398 int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
400 extern struct bus_type iio_bus_type;
403 * iio_put_device() - reference counted deallocation of struct device
404 * @dev: the iio_device containing the device
406 static inline void iio_put_device(struct iio_dev *indio_dev)
409 put_device(&indio_dev->dev);
412 /* Can we make this smaller? */
413 #define IIO_ALIGN L1_CACHE_BYTES
415 * iio_allocate_device() - allocate an iio_dev from a driver
416 * @sizeof_priv: Space to allocate for private structure.
418 struct iio_dev *iio_allocate_device(int sizeof_priv);
420 static inline void *iio_priv(const struct iio_dev *indio_dev)
422 return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
425 static inline struct iio_dev *iio_priv_to_dev(void *priv)
427 return (struct iio_dev *)((char *)priv -
428 ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
432 * iio_free_device() - free an iio_dev from a driver
433 * @dev: the iio_dev associated with the device
435 void iio_free_device(struct iio_dev *indio_dev);
438 * iio_buffer_enabled() - helper function to test if the buffer is enabled
439 * @indio_dev: IIO device info structure for device
441 static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
443 return indio_dev->currentmode
444 & (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE);
448 * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
449 * @indio_dev: IIO device info structure for device
451 #if defined(CONFIG_DEBUG_FS)
452 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
454 return indio_dev->debugfs_dentry;
457 static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
463 #endif /* _INDUSTRIAL_IO_H_ */