- 根目录:
- drivers
- staging
- iio
- iio.h
/* The industrial I/O core
*
* Copyright (c) 2008 Jonathan Cameron
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 as published by
* the Free Software Foundation.
*/
#ifndef _INDUSTRIAL_IO_H_
#define _INDUSTRIAL_IO_H_
#include <linux/device.h>
#include <linux/cdev.h>
#include "types.h"
/* IIO TODO LIST */
/*
* Provide means of adjusting timer accuracy.
* Currently assumes nano seconds.
*/
enum iio_data_type {
IIO_RAW,
IIO_PROCESSED,
};
/* Could add the raw attributes as well - allowing buffer only devices */
enum iio_chan_info_enum {
/* 0 is reserverd for raw attributes */
IIO_CHAN_INFO_SCALE = 1,
IIO_CHAN_INFO_OFFSET,
IIO_CHAN_INFO_CALIBSCALE,
IIO_CHAN_INFO_CALIBBIAS,
IIO_CHAN_INFO_PEAK,
IIO_CHAN_INFO_PEAK_SCALE,
IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW,
IIO_CHAN_INFO_AVERAGE_RAW,
IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY,
};
#define IIO_CHAN_INFO_SHARED_BIT(type) BIT(type*2)
#define IIO_CHAN_INFO_SEPARATE_BIT(type) BIT(type*2 + 1)
#define IIO_CHAN_INFO_SCALE_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SCALE)
#define IIO_CHAN_INFO_SCALE_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SCALE)
#define IIO_CHAN_INFO_OFFSET_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_OFFSET)
#define IIO_CHAN_INFO_OFFSET_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_OFFSET)
#define IIO_CHAN_INFO_CALIBSCALE_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBSCALE)
#define IIO_CHAN_INFO_CALIBSCALE_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_CALIBSCALE)
#define IIO_CHAN_INFO_CALIBBIAS_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_CALIBBIAS)
#define IIO_CHAN_INFO_CALIBBIAS_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_CALIBBIAS)
#define IIO_CHAN_INFO_PEAK_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PEAK)
#define IIO_CHAN_INFO_PEAK_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PEAK)
#define IIO_CHAN_INFO_PEAKSCALE_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PEAKSCALE)
#define IIO_CHAN_INFO_PEAKSCALE_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PEAKSCALE)
#define IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT( \
IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW)
#define IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT( \
IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW)
#define IIO_CHAN_INFO_AVERAGE_RAW_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_AVERAGE_RAW)
#define IIO_CHAN_INFO_AVERAGE_RAW_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_AVERAGE_RAW)
#define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SHARED_BIT \
IIO_CHAN_INFO_SHARED_BIT( \
IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)
#define IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY_SEPARATE_BIT \
IIO_CHAN_INFO_SEPARATE_BIT( \
IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY)
enum iio_endian {
IIO_CPU,
IIO_BE,
IIO_LE,
};
/**
* struct iio_chan_spec - specification of a single channel
* @type: What type of measurement is the channel making.
* @channel: What number or name do we wish to asign the channel.
* @channel2: If there is a second number for a differential
* channel then this is it. If modified is set then the
* value here specifies the modifier.
* @address: Driver specific identifier.
* @scan_index: Monotonic index to give ordering in scans when read
* from a buffer.
* @scan_type: Sign: 's' or 'u' to specify signed or unsigned
* realbits: Number of valid bits of data
* storage_bits: Realbits + padding
* shift: Shift right by this before masking out
* realbits.
* endianness: little or big endian
* @info_mask: What information is to be exported about this channel.
* This includes calibbias, scale etc.
* @event_mask: What events can this channel produce.
* @extend_name: Allows labeling of channel attributes with an
* informative name. Note this has no effect codes etc,
* unlike modifiers.
* @datasheet_name: A name used in in kernel mapping of channels. It should
* corrspond to the first name that the channel is referred
* to by in the datasheet (e.g. IND), or the nearest
* possible compound name (e.g. IND-INC).
* @processed_val: Flag to specify the data access attribute should be
* *_input rather than *_raw.
* @modified: Does a modifier apply to this channel. What these are
* depends on the channel type. Modifier is set in
* channel2. Examples are IIO_MOD_X for axial sensors about
* the 'x' axis.
* @indexed: Specify the channel has a numerical index. If not,
* the value in channel will be suppressed for attribute
* but not for event codes. Typically set it to 0 when
* the index is false.
* @differential: Channel is differential.
*/
struct iio_chan_spec {
enum iio_chan_type type;
int channel;
int channel2;
unsigned long address;
int scan_index;
struct {
char sign;
u8 realbits;
u8 storagebits;
u8 shift;
enum iio_endian endianness;
} scan_type;
long info_mask;
long event_mask;
char *extend_name;
const char *datasheet_name;
unsigned processed_val:1;
unsigned modified:1;
unsigned indexed:1;
unsigned output:1;
unsigned differential:1;
};
#define IIO_ST(si, rb, sb, sh) \
{ .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
/* Macro assumes input channels */
#define IIO_CHAN(_type, _mod, _indexed, _proc, _name, _chan, _chan2, \
_inf_mask, _address, _si, _stype, _event_mask) \
{ .type = _type, \
.output = 0, \
.modified = _mod, \
.indexed = _indexed, \
.processed_val = _proc, \
.extend_name = _name, \
.channel = _chan, \
.channel2 = _chan2, \
.info_mask = _inf_mask, \
.address = _address, \
.scan_index = _si, \
.scan_type = _stype, \
.event_mask = _event_mask }
#define IIO_CHAN_SOFT_TIMESTAMP(_si) \
{ .type = IIO_TIMESTAMP, .channel = -1, \
.scan_index = _si, .scan_type = IIO_ST('s', 64, 64, 0) }
/**
* iio_get_time_ns() - utility function to get a time stamp for events etc
**/
static inline s64 iio_get_time_ns(void)
{
struct timespec ts;
/*
* calls getnstimeofday.
* If hrtimers then up to ns accurate, if not microsecond.
*/
ktime_get_real_ts(&ts);
return timespec_to_ns(&ts);
}
/* Device operating modes */
#define INDIO_DIRECT_MODE 0x01
#define INDIO_BUFFER_TRIGGERED 0x02
#define INDIO_BUFFER_HARDWARE 0x08
#define INDIO_ALL_BUFFER_MODES \
(INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE)
/* Vast majority of this is set by the industrialio subsystem on a
* call to iio_device_register. */
#define IIO_VAL_INT 1
#define IIO_VAL_INT_PLUS_MICRO 2
#define IIO_VAL_INT_PLUS_NANO 3
struct iio_trigger; /* forward declaration */
struct iio_dev;
/**
* struct iio_info - constant information about device
* @driver_module: module structure used to ensure correct
* ownership of chrdevs etc
* @event_attrs: event control attributes
* @attrs: general purpose device attributes
* @read_raw: function to request a value from the device.
* mask specifies which value. Note 0 means a reading of
* the channel in question. Return value will specify the
* type of value returned by the device. val and val2 will
* contain the elements making up the returned value.
* @write_raw: function to write a value to the device.
* Parameters are the same as for read_raw.
* @write_raw_get_fmt: callback function to query the expected
* format/precision. If not set by the driver, write_raw
* returns IIO_VAL_INT_PLUS_MICRO.
* @read_event_config: find out if the event is enabled.
* @write_event_config: set if the event is enabled.
* @read_event_value: read a value associated with the event. Meaning
* is event dependant. event_code specifies which event.
* @write_event_value: write the value associate with the event.
* Meaning is event dependent.
* @validate_trigger: function to validate the trigger when the
* current trigger gets changed.
**/
struct iio_info {
struct module *driver_module;
struct attribute_group *event_attrs;
const struct attribute_group *attrs;
int (*read_raw)(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val,
int *val2,
long mask);
int (*write_raw)(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val,
int val2,
long mask);
int (*write_raw_get_fmt)(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
long mask);
int (*read_event_config)(struct iio_dev *indio_dev,
u64 event_code);
int (*write_event_config)(struct iio_dev *indio_dev,
u64 event_code,
int state);
int (*read_event_value)(struct iio_dev *indio_dev,
u64 event_code,
int *val);
int (*write_event_value)(struct iio_dev *indio_dev,
u64 event_code,
int val);
int (*validate_trigger)(struct iio_dev *indio_dev,
struct iio_trigger *trig);
int (*update_scan_mode)(struct iio_dev *indio_dev,
const unsigned long *scan_mask);
};
/**
* struct iio_buffer_setup_ops - buffer setup related callbacks
* @preenable: [DRIVER] function to run prior to marking buffer enabled
* @postenable: [DRIVER] function to run after marking buffer enabled
* @predisable: [DRIVER] function to run prior to marking buffer
* disabled
* @postdisable: [DRIVER] function to run after marking buffer disabled
*/
struct iio_buffer_setup_ops {
int (*preenable)(struct iio_dev *);
int (*postenable)(struct iio_dev *);
int (*predisable)(struct iio_dev *);
int (*postdisable)(struct iio_dev *);
};
/**
* struct iio_dev - industrial I/O device
* @id: [INTERN] used to identify device internally
* @modes: [DRIVER] operating modes supported by device
* @currentmode: [DRIVER] current operating mode
* @dev: [DRIVER] device structure, should be assigned a parent
* and owner
* @event_interface: [INTERN] event chrdevs associated with interrupt lines
* @buffer: [DRIVER] any buffer present
* @mlock: [INTERN] lock used to prevent simultaneous device state
* changes
* @available_scan_masks: [DRIVER] optional array of allowed bitmasks
* @masklength: [INTERN] the length of the mask established from
* channels
* @active_scan_mask: [INTERN] union of all scan masks requested by buffers
* @trig: [INTERN] current device trigger (buffer modes)
* @pollfunc: [DRIVER] function run on trigger being received
* @channels: [DRIVER] channel specification structure table
* @num_channels: [DRIVER] number of chanels specified in @channels.
* @channel_attr_list: [INTERN] keep track of automatically created channel
* attributes
* @chan_attr_group: [INTERN] group for all attrs in base directory
* @name: [DRIVER] name of the device.
* @info: [DRIVER] callbacks and constant info from driver
* @chrdev: [INTERN] associated character device
* @groups: [INTERN] attribute groups
* @groupcounter: [INTERN] index of next attribute group
* @flags: [INTERN] file ops related flags including busy flag.
**/
struct iio_dev {
int id;
int modes;
int currentmode;
struct device dev;
struct iio_event_interface *event_interface;
struct iio_buffer *buffer;
struct mutex mlock;
unsigned long *available_scan_masks;
unsigned masklength;
unsigned long *active_scan_mask;
struct iio_trigger *trig;
struct iio_poll_func *pollfunc;
struct iio_chan_spec const *channels;
int num_channels;
struct list_head channel_attr_list;
struct attribute_group chan_attr_group;
const char *name;
const struct iio_info *info;
const struct iio_buffer_setup_ops *setup_ops;
struct cdev chrdev;
#define IIO_MAX_GROUPS 6
const struct attribute_group *groups[IIO_MAX_GROUPS + 1];
int groupcounter;
unsigned long flags;
};
/**
* iio_find_channel_from_si() - get channel from its scan index
* @indio_dev: device
* @si: scan index to match
*/
const struct iio_chan_spec
*iio_find_channel_from_si(struct iio_dev *indio_dev, int si);
/**
* iio_device_register() - register a device with the IIO subsystem
* @indio_dev: Device structure filled by the device driver
**/
int iio_device_register(struct iio_dev *indio_dev);
/**
* iio_device_unregister() - unregister a device from the IIO subsystem
* @indio_dev: Device structure representing the device.
**/
void iio_device_unregister(struct iio_dev *indio_dev);
/**
* iio_push_event() - try to add event to the list for userspace reading
* @indio_dev: IIO device structure
* @ev_code: What event
* @timestamp: When the event occurred
**/
int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp);
extern struct bus_type iio_bus_type;
/**
* iio_put_device() - reference counted deallocation of struct device
* @dev: the iio_device containing the device
**/
static inline void iio_put_device(struct iio_dev *indio_dev)
{
if (indio_dev)
put_device(&indio_dev->dev);
};
/* Can we make this smaller? */
#define IIO_ALIGN L1_CACHE_BYTES
/**
* iio_allocate_device() - allocate an iio_dev from a driver
* @sizeof_priv: Space to allocate for private structure.
**/
struct iio_dev *iio_allocate_device(int sizeof_priv);
static inline void *iio_priv(const struct iio_dev *indio_dev)
{
return (char *)indio_dev + ALIGN(sizeof(struct iio_dev), IIO_ALIGN);
}
static inline struct iio_dev *iio_priv_to_dev(void *priv)
{
return (struct iio_dev *)((char *)priv -
ALIGN(sizeof(struct iio_dev), IIO_ALIGN));
}
/**
* iio_free_device() - free an iio_dev from a driver
* @dev: the iio_dev associated with the device
**/
void iio_free_device(struct iio_dev *indio_dev);
/**
* iio_buffer_enabled() - helper function to test if the buffer is enabled
* @indio_dev: IIO device info structure for device
**/
static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
{
return indio_dev->currentmode
& (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE);
};
#endif /* _INDUSTRIAL_IO_H_ */