/* 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/iio/types.h>
/* IIO TODO LIST */
/*
* Provide means of adjusting timer accuracy.
* Currently assumes nano seconds.
*/
enum iio_chan_info_enum {
IIO_CHAN_INFO_RAW = 0,
IIO_CHAN_INFO_PROCESSED,
IIO_CHAN_INFO_SCALE,
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,
IIO_CHAN_INFO_SAMP_FREQ,
IIO_CHAN_INFO_FREQUENCY,
IIO_CHAN_INFO_PHASE,
IIO_CHAN_INFO_HARDWAREGAIN,
IIO_CHAN_INFO_HYSTERESIS,
};
enum iio_endian {
IIO_CPU,
IIO_BE,
IIO_LE,
};
struct iio_chan_spec;
struct iio_dev;
/**
* struct iio_chan_spec_ext_info - Extended channel info attribute
* @name: Info attribute name
* @shared: Whether this attribute is shared between all channels.
* @read: Read callback for this info attribute, may be NULL.
* @write: Write callback for this info attribute, may be NULL.
* @private: Data private to the driver.
*/
struct iio_chan_spec_ext_info {
const char *name;
bool shared;
ssize_t (*read)(struct iio_dev *, uintptr_t private,
struct iio_chan_spec const *, char *buf);
ssize_t (*write)(struct iio_dev *, uintptr_t private,
struct iio_chan_spec const *, const char *buf,
size_t len);
uintptr_t private;
};
/**
* struct iio_enum - Enum channel info attribute
* @items: An array of strings.
* @num_items: Length of the item array.
* @set: Set callback function, may be NULL.
* @get: Get callback function, may be NULL.
*
* The iio_enum struct can be used to implement enum style channel attributes.
* Enum style attributes are those which have a set of strings which map to
* unsigned integer values. The IIO enum helper code takes care of mapping
* between value and string as well as generating a "_available" file which
* contains a list of all available items. The set callback will be called when
* the attribute is updated. The last parameter is the index to the newly
* activated item. The get callback will be used to query the currently active
* item and is supposed to return the index for it.
*/
struct iio_enum {
const char * const *items;
unsigned int num_items;
int (*set)(struct iio_dev *, const struct iio_chan_spec *, unsigned int);
int (*get)(struct iio_dev *, const struct iio_chan_spec *);
};
ssize_t iio_enum_available_read(struct iio_dev *indio_dev,
uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
ssize_t iio_enum_read(struct iio_dev *indio_dev,
uintptr_t priv, const struct iio_chan_spec *chan, char *buf);
ssize_t iio_enum_write(struct iio_dev *indio_dev,
uintptr_t priv, const struct iio_chan_spec *chan, const char *buf,
size_t len);
/**
* IIO_ENUM() - Initialize enum extended channel attribute
* @_name: Attribute name
* @_shared: Whether the attribute is shared between all channels
* @_e: Pointer to an iio_enum struct
*
* This should usually be used together with IIO_ENUM_AVAILABLE()
*/
#define IIO_ENUM(_name, _shared, _e) \
{ \
.name = (_name), \
.shared = (_shared), \
.read = iio_enum_read, \
.write = iio_enum_write, \
.private = (uintptr_t)(_e), \
}
/**
* IIO_ENUM_AVAILABLE() - Initialize enum available extended channel attribute
* @_name: Attribute name ("_available" will be appended to the name)
* @_e: Pointer to an iio_enum struct
*
* Creates a read only attribute which lists all the available enum items in a
* space separated list. This should usually be used together with IIO_ENUM()
*/
#define IIO_ENUM_AVAILABLE(_name, _e) \
{ \
.name = (_name "_available"), \
.shared = true, \
.read = iio_enum_available_read, \
.private = (uintptr_t)(_e), \
}
/**
* struct iio_chan_spec - specification of a single channel
* @type: What type of measurement is the channel making.
* @channel: What number do we wish to assign 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.
* @info_mask_separate: What information is to be exported that is specific to
* this channel.
* @info_mask_shared_by_type: What information is to be exported that is shared
* by all channels of the same type.
* @event_mask: What events can this channel produce.
* @ext_info: Array of extended info attributes for this channel.
* The array is NULL terminated, the last element should
* have its name field set to NULL.
* @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
* correspond 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).
* @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 channel index number will be suppressed for sysfs
* attributes but not for event codes.
* @output: Channel is output.
* @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 info_mask_separate;
long info_mask_shared_by_type;
long event_mask;
const struct iio_chan_spec_ext_info *ext_info;
const char *extend_name;
const char *datasheet_name;
unsigned modified:1;
unsigned indexed:1;
unsigned output:1;
unsigned differential:1;
};
/**
* iio_channel_has_info() - Checks whether a channel supports a info attribute
* @chan: The channel to be queried
* @type: Type of the info attribute to be checked
*
* Returns true if the channels supports reporting values for the given info
* attribute type, false otherwise.
*/
static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
enum iio_chan_info_enum type)
{
return (chan->info_mask_separate & type) |
(chan->info_mask_shared_by_type & type);
}
#define IIO_ST(si, rb, sb, sh) \
{ .sign = si, .realbits = rb, .storagebits = sb, .shift = sh }
#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)
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 associated with the event.
* Meaning is event dependent.
* @validate_trigger: function to validate the trigger when the
* current trigger gets changed.
* @update_scan_mode: function to configure device and scan buffer when
* channels have changed
* @debugfs_reg_access: function to read or write register value of device
**/
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);
int (*debugfs_reg_access)(struct iio_dev *indio_dev,
unsigned reg, unsigned writeval,
unsigned *readval);
};
/**
* 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
* @validate_scan_mask: [DRIVER] function callback to check whether a given
* scan mask is valid for the device.
*/
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 *);
bool (*validate_scan_mask)(struct iio_dev *indio_dev,
const unsigned long *scan_mask);
};
/**
* 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
* @buffer_list: [INTERN] list of all buffers currently attached
* @scan_bytes: [INTERN] num bytes captured to be fed to buffer demux
* @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
* @scan_timestamp: [INTERN] set if any buffers have requested timestamp
* @scan_index_timestamp:[INTERN] cache of the index to the timestamp
* @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 channels 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
* @info_exist_lock: [INTERN] lock to prevent use during removal
* @setup_ops: [DRIVER] callbacks to call before and after buffer
* enable/disable
* @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.
* @debugfs_dentry: [INTERN] device specific debugfs dentry.
* @cached_reg_addr: [INTERN] cached register address for debugfs reads.
*/
struct iio_dev {
int id;
int modes;
int currentmode;
struct device dev;
struct iio_event_interface *event_interface;
struct iio_buffer *buffer;
struct list_head buffer_list;
int scan_bytes;
struct mutex mlock;
const unsigned long *available_scan_masks;
unsigned masklength;
const unsigned long *active_scan_mask;
bool scan_timestamp;
unsigned scan_index_timestamp;
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;
struct mutex info_exist_lock;
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;
#if defined(CONFIG_DEBUG_FS)
struct dentry *debugfs_dentry;
unsigned cached_reg_addr;
#endif
};
/**
* 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_device_put() - reference counted deallocation of struct device
* @indio_dev: IIO device structure containing the device
**/
static inline void iio_device_put(struct iio_dev *indio_dev)
{
if (indio_dev)
put_device(&indio_dev->dev);
};
/**
* dev_to_iio_dev() - Get IIO device struct from a device struct
* @dev: The device embedded in the IIO device
*
* Note: The device must be a IIO device, otherwise the result is undefined.
*/
static inline struct iio_dev *dev_to_iio_dev(struct device *dev)
{
return container_of(dev, struct iio_dev, dev);
}
/**
* iio_device_get() - increment reference count for the device
* @indio_dev: IIO device structure
*
* Returns: The passed IIO device
**/
static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
{
return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
}
/**
* iio_device_set_drvdata() - Set device driver data
* @indio_dev: IIO device structure
* @data: Driver specific data
*
* Allows to attach an arbitrary pointer to an IIO device, which can later be
* retrieved by iio_device_get_drvdata().
*/
static inline void iio_device_set_drvdata(struct iio_dev *indio_dev, void *data)
{
dev_set_drvdata(&indio_dev->dev, data);
}
/**
* iio_device_get_drvdata() - Get device driver data
* @indio_dev: IIO device structure
*
* Returns the data previously set with iio_device_set_drvdata()
*/
static inline void *iio_device_get_drvdata(struct iio_dev *indio_dev)
{
return dev_get_drvdata(&indio_dev->dev);
}
/* Can we make this smaller? */
#define IIO_ALIGN L1_CACHE_BYTES
/**
* iio_device_alloc() - allocate an iio_dev from a driver
* @sizeof_priv: Space to allocate for private structure.
**/
struct iio_dev *iio_device_alloc(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_device_free() - free an iio_dev from a driver
* @indio_dev: the iio_dev associated with the device
**/
void iio_device_free(struct iio_dev *indio_dev);
/**
* iio_buffer_enabled() - helper function to test if the buffer is enabled
* @indio_dev: IIO device structure for device
**/
static inline bool iio_buffer_enabled(struct iio_dev *indio_dev)
{
return indio_dev->currentmode
& (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE);
};
/**
* iio_get_debugfs_dentry() - helper function to get the debugfs_dentry
* @indio_dev: IIO device structure for device
**/
#if defined(CONFIG_DEBUG_FS)
static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
{
return indio_dev->debugfs_dentry;
};
#else
static inline struct dentry *iio_get_debugfs_dentry(struct iio_dev *indio_dev)
{
return NULL;
};
#endif
int iio_str_to_fixpoint(const char *str, int fract_mult, int *integer,
int *fract);
/**
* IIO_DEGREE_TO_RAD() - Convert degree to rad
* @deg: A value in degree
*
* Returns the given value converted from degree to rad
*/
#define IIO_DEGREE_TO_RAD(deg) (((deg) * 314159ULL + 9000000ULL) / 18000000ULL)
/**
* IIO_G_TO_M_S_2() - Convert g to meter / second**2
* @g: A value in g
*
* Returns the given value converted from g to meter / second**2
*/
#define IIO_G_TO_M_S_2(g) ((g) * 980665ULL / 100000ULL)
#endif /* _INDUSTRIAL_IO_H_ */