- 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 <linux/irq.h>
#include "sysfs.h"
#include "chrdev.h"
/* IIO TODO LIST */
/*
* Provide means of adjusting timer accuracy.
* Currently assumes nano seconds.
*/
/* Event interface flags */
#define IIO_BUSY_BIT_POS 1
/* naughty temporary hack to match these against the event version
- need to flattern these together */
enum iio_chan_type {
/* real channel types */
IIO_IN,
IIO_CURRENT,
IIO_POWER,
IIO_ACCEL,
IIO_IN_DIFF,
IIO_GYRO,
IIO_MAGN,
IIO_LIGHT,
IIO_INTENSITY,
IIO_PROXIMITY,
IIO_TEMP,
IIO_INCLI,
IIO_ROT,
IIO_ANGL,
IIO_TIMESTAMP,
};
#define IIO_MOD_X 0
#define IIO_MOD_LIGHT_BOTH 0
#define IIO_MOD_Y 1
#define IIO_MOD_LIGHT_IR 1
#define IIO_MOD_Z 2
#define IIO_MOD_X_AND_Y 3
#define IIO_MOD_X_ANX_Z 4
#define IIO_MOD_Y_AND_Z 5
#define IIO_MOD_X_AND_Y_AND_Z 6
#define IIO_MOD_X_OR_Y 7
#define IIO_MOD_X_OR_Z 8
#define IIO_MOD_Y_OR_Z 9
#define IIO_MOD_X_OR_Y_OR_Z 10
/* Could add the raw attributes as well - allowing buffer only devices */
enum iio_chan_info_enum {
IIO_CHAN_INFO_SCALE_SHARED,
IIO_CHAN_INFO_SCALE_SEPARATE,
IIO_CHAN_INFO_OFFSET_SHARED,
IIO_CHAN_INFO_OFFSET_SEPARATE,
IIO_CHAN_INFO_CALIBSCALE_SHARED,
IIO_CHAN_INFO_CALIBSCALE_SEPARATE,
IIO_CHAN_INFO_CALIBBIAS_SHARED,
IIO_CHAN_INFO_CALIBBIAS_SEPARATE,
IIO_CHAN_INFO_PEAK_SHARED,
IIO_CHAN_INFO_PEAK_SEPARATE,
IIO_CHAN_INFO_PEAK_SCALE_SHARED,
IIO_CHAN_INFO_PEAK_SCALE_SEPARATE,
};
/**
* 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.
* @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.
* @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.
*/
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;
} scan_type;
const long info_mask;
const long event_mask;
const char *extend_name;
unsigned processed_val:1;
unsigned modified:1;
unsigned indexed:1;
};
/* Meant for internal use only */
void __iio_device_attr_deinit(struct device_attribute *dev_attr);
int __iio_device_attr_init(struct device_attribute *dev_attr,
const char *postfix,
struct iio_chan_spec const *chan,
ssize_t (*readfunc)(struct device *dev,
struct device_attribute *attr,
char *buf),
ssize_t (*writefunc)(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len),
bool generic);
#define IIO_ST(si, rb, sb, sh) \
{ .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
#define IIO_CHAN(_type, _mod, _indexed, _proc, _name, _chan, _chan2, \
_inf_mask, _address, _si, _stype, _event_mask) \
{ .type = _type, \
.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) }
int __iio_add_chan_devattr(const char *postfix,
const char *group,
struct iio_chan_spec const *chan,
ssize_t (*func)(struct device *dev,
struct device_attribute *attr,
char *buf),
ssize_t (*writefunc)(struct device *dev,
struct device_attribute *attr,
const char *buf,
size_t len),
int mask,
bool generic,
struct device *dev,
struct list_head *attr_list);
/**
* 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_RING_TRIGGERED 0x02
#define INDIO_RING_HARDWARE_BUFFER 0x08
#define INDIO_ALL_RING_MODES (INDIO_RING_TRIGGERED | INDIO_RING_HARDWARE_BUFFER)
/* 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
/**
* struct iio_info - constant information about device
* @driver_module: module structure used to ensure correct
* ownership of chrdevs etc
* @num_interrupt_lines:number of physical interrupt lines from device
* @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.
* @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.
**/
struct iio_info {
struct module *driver_module;
int num_interrupt_lines;
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 (*read_event_config)(struct iio_dev *indio_dev,
int event_code);
int (*write_event_config)(struct iio_dev *indio_dev,
int event_code,
int state);
int (*read_event_value)(struct iio_dev *indio_dev,
int event_code,
int *val);
int (*write_event_value)(struct iio_dev *indio_dev,
int event_code,
int val);
};
/**
* struct iio_dev - industrial I/O device
* @id: [INTERN] used to identify device internally
* @dev_data: [DRIVER] device specific data
* @modes: [DRIVER] operating modes supported by device
* @currentmode: [DRIVER] current operating mode
* @dev: [DRIVER] device structure, should be assigned a parent
* and owner
* @event_interfaces: [INTERN] event chrdevs associated with interrupt lines
* @ring: [DRIVER] any ring buffer present
* @mlock: [INTERN] lock used to prevent simultaneous device state
* changes
* @available_scan_masks: [DRIVER] optional array of allowed bitmasks
* @trig: [INTERN] current device trigger (ring 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.
* @name: [DRIVER] name of the device.
**/
struct iio_dev {
int id;
void *dev_data;
int modes;
int currentmode;
struct device dev;
struct iio_event_interface *event_interfaces;
struct iio_ring_buffer *ring;
struct mutex mlock;
u32 *available_scan_masks;
struct iio_trigger *trig;
struct iio_poll_func *pollfunc;
struct iio_chan_spec const *channels;
int num_channels;
struct list_head channel_attr_list;
const char *name;
const struct iio_info *info;
};
/**
* iio_device_register() - register a device with the IIO subsystem
* @dev_info: Device structure filled by the device driver
**/
int iio_device_register(struct iio_dev *dev_info);
/**
* iio_device_unregister() - unregister a device from the IIO subsystem
* @dev_info: Device structure representing the device.
**/
void iio_device_unregister(struct iio_dev *dev_info);
/**
* iio_push_event() - try to add event to the list for userspace reading
* @dev_info: IIO device structure
* @ev_line: Which event line (hardware interrupt)
* @ev_code: What event
* @timestamp: When the event occurred
**/
int iio_push_event(struct iio_dev *dev_info,
int ev_line,
int ev_code,
s64 timestamp);
/* Used to distinguish between bipolar and unipolar scan elemenents.
* Whilst this may seem obvious, we may well want to change the representation
* in the future!*/
#define IIO_SIGNED(a) -(a)
#define IIO_UNSIGNED(a) (a)
extern dev_t iio_devt;
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 *dev)
{
if (dev)
put_device(&dev->dev);
};
/**
* to_iio_dev() - get iio_dev for which we have the struct device
* @d: the struct device
**/
static inline struct iio_dev *to_iio_dev(struct device *d)
{
return container_of(d, struct iio_dev, dev);
};
/**
* iio_dev_get_devdata() - helper function gets device specific data
* @d: the iio_dev associated with the device
**/
static inline void *iio_dev_get_devdata(struct iio_dev *d)
{
return d->dev_data;
}
/* 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 *dev)
{
return (char *)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 *dev);
/**
* iio_put() - internal module reference count reduce
**/
void iio_put(void);
/**
* iio_get() - internal module reference count increase
**/
void iio_get(void);
/**
* iio_device_get_chrdev_minor() - get an unused minor number
**/
int iio_device_get_chrdev_minor(void);
void iio_device_free_chrdev_minor(int val);
/**
* iio_ring_enabled() - helper function to test if any form of ring is enabled
* @dev_info: IIO device info structure for device
**/
static inline bool iio_ring_enabled(struct iio_dev *dev_info)
{
return dev_info->currentmode
& (INDIO_RING_TRIGGERED
| INDIO_RING_HARDWARE_BUFFER);
};
struct ida;
int iio_get_new_ida_val(struct ida *this_ida);
void iio_free_ida_val(struct ida *this_ida, int id);
#endif /* _INDUSTRIAL_IO_H_ */