Edit File: 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/iio/types.h> #include <linux/of.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_HIGH_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, IIO_CHAN_INFO_INT_TIME, IIO_CHAN_INFO_ENABLE, IIO_CHAN_INFO_CALIBHEIGHT, IIO_CHAN_INFO_CALIBWEIGHT, IIO_CHAN_INFO_DEBOUNCE_COUNT, IIO_CHAN_INFO_DEBOUNCE_TIME, IIO_CHAN_INFO_CALIBEMISSIVITY, IIO_CHAN_INFO_OVERSAMPLING_RATIO, }; enum iio_shared_by { IIO_SEPARATE, IIO_SHARED_BY_TYPE, IIO_SHARED_BY_DIR, IIO_SHARED_BY_ALL }; 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; enum iio_shared_by 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 = IIO_SHARED_BY_TYPE, \ .read = iio_enum_available_read, \ .private = (uintptr_t)(_e), \ } /** * struct iio_mount_matrix - iio mounting matrix * @rotation: 3 dimensional space rotation matrix defining sensor alignment with * main hardware */ struct iio_mount_matrix { const char *rotation[9]; }; ssize_t iio_show_mount_matrix(struct iio_dev *indio_dev, uintptr_t priv, const struct iio_chan_spec *chan, char *buf); int of_iio_read_mount_matrix(const struct device *dev, const char *propname, struct iio_mount_matrix *matrix); typedef const struct iio_mount_matrix * (iio_get_mount_matrix_t)(const struct iio_dev *indio_dev, const struct iio_chan_spec *chan); /** * IIO_MOUNT_MATRIX() - Initialize mount matrix extended channel attribute * @_shared: Whether the attribute is shared between all channels * @_get: Pointer to an iio_get_mount_matrix_t accessor */ #define IIO_MOUNT_MATRIX(_shared, _get) \ { \ .name = "mount_matrix", \ .shared = (_shared), \ .read = iio_show_mount_matrix, \ .private = (uintptr_t)(_get), \ } /** * struct iio_event_spec - specification for a channel event * @type: Type of the event * @dir: Direction of the event * @mask_separate: Bit mask of enum iio_event_info values. Attributes * set in this mask will be registered per channel. * @mask_shared_by_type: Bit mask of enum iio_event_info values. Attributes * set in this mask will be shared by channel type. * @mask_shared_by_dir: Bit mask of enum iio_event_info values. Attributes * set in this mask will be shared by channel type and * direction. * @mask_shared_by_all: Bit mask of enum iio_event_info values. Attributes * set in this mask will be shared by all channels. */ struct iio_event_spec { enum iio_event_type type; enum iio_event_direction dir; unsigned long mask_separate; unsigned long mask_shared_by_type; unsigned long mask_shared_by_dir; unsigned long mask_shared_by_all; }; /** * 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 * storagebits: Realbits + padding * shift: Shift right by this before masking out * realbits. * repeat: Number of times real/storage bits * repeats. When the repeat element is * more than 1, then the type element in * sysfs will show a repeat value. * Otherwise, the number of repetitions is * omitted. * endianness: little or big endian * @info_mask_separate: What information is to be exported that is specific to * this channel. * @info_mask_separate_available: What availability 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. * @info_mask_shared_by_type_available: What availability information is to be * exported that is shared by all channels of the same * type. * @info_mask_shared_by_dir: What information is to be exported that is shared * by all channels of the same direction. * @info_mask_shared_by_dir_available: What availability information is to be * exported that is shared by all channels of the same * direction. * @info_mask_shared_by_all: What information is to be exported that is shared * by all channels. * @info_mask_shared_by_all_available: What availability information is to be * exported that is shared by all channels. * @event_spec: Array of events which should be registered for this * channel. * @num_event_specs: Size of the event_spec array. * @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; u8 repeat; enum iio_endian endianness; } scan_type; long info_mask_separate; long info_mask_separate_available; long info_mask_shared_by_type; long info_mask_shared_by_type_available; long info_mask_shared_by_dir; long info_mask_shared_by_dir_available; long info_mask_shared_by_all; long info_mask_shared_by_all_available; const struct iio_event_spec *event_spec; unsigned int num_event_specs; 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 & BIT(type)) | (chan->info_mask_shared_by_type & BIT(type)) | (chan->info_mask_shared_by_dir & BIT(type)) | (chan->info_mask_shared_by_all & BIT(type)); } /** * iio_channel_has_available() - Checks if a channel has an available attribute * @chan: The channel to be queried * @type: Type of the available attribute to be checked * * Returns true if the channel supports reporting available values for the * given attribute type, false otherwise. */ static inline bool iio_channel_has_available(const struct iio_chan_spec *chan, enum iio_chan_info_enum type) { return (chan->info_mask_separate_available & BIT(type)) | (chan->info_mask_shared_by_type_available & BIT(type)) | (chan->info_mask_shared_by_dir_available & BIT(type)) | (chan->info_mask_shared_by_all_available & BIT(type)); } #define IIO_CHAN_SOFT_TIMESTAMP(_si) { \ .type = IIO_TIMESTAMP, \ .channel = -1, \ .scan_index = _si, \ .scan_type = { \ .sign = 's', \ .realbits = 64, \ .storagebits = 64, \ }, \ } /** * iio_get_time_ns() - utility function to get a time stamp for events etc **/ static inline s64 iio_get_time_ns(void) { return ktime_get_real_ns(); } /* Device operating modes */ #define INDIO_DIRECT_MODE 0x01 #define INDIO_BUFFER_TRIGGERED 0x02 #define INDIO_BUFFER_SOFTWARE 0x04 #define INDIO_BUFFER_HARDWARE 0x08 #define INDIO_EVENT_TRIGGERED 0x10 #define INDIO_ALL_BUFFER_MODES \ (INDIO_BUFFER_TRIGGERED | INDIO_BUFFER_HARDWARE | INDIO_BUFFER_SOFTWARE) #define INDIO_MAX_RAW_ELEMENTS 4 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. * @read_raw_multi: function to return values 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. vals pointer * contain the elements making up the returned value. * max_len specifies maximum number of elements * vals pointer can contain. val_len is used to return * length of valid elements in vals. * @read_avail: function to return the available values from the device. * mask specifies which value. Note 0 means the available * values for the channel in question. Return value * specifies if a IIO_AVAIL_LIST or a IIO_AVAIL_RANGE is * returned in vals. The type of the vals are returned in * type and the number of vals is returned in length. For * ranges, there are always three vals returned; min, step * and max. For lists, all possible values are enumerated. * @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 configuration value associated with the event. * @write_event_value: write a configuration value for the event. * @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 * @of_xlate: function pointer to obtain channel specifier index. * When #iio-cells is greater than '0', the driver could * provide a custom of_xlate function that reads the * *args* and returns the appropriate index in registered * IIO channels array. * @hwfifo_set_watermark: function pointer to set the current hardware * fifo watermark level; see hwfifo_* entries in * Documentation/ABI/testing/sysfs-bus-iio for details on * how the hardware fifo operates * @hwfifo_flush_to_buffer: function pointer to flush the samples stored * in the hardware fifo to the device buffer. The driver * should not flush more than count samples. The function * must return the number of samples flushed, 0 if no * samples were flushed or a negative integer if no samples * were flushed and there was an error. **/ struct iio_info { struct module *driver_module; const 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 (*read_raw_multi)(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int max_len, int *vals, int *val_len, long mask); int (*read_avail)(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, const int **vals, int *type, int *length, 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, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir); int (*write_event_config)(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, int state); int (*read_event_value)(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, enum iio_event_info info, int *val, int *val2); int (*write_event_value)(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, enum iio_event_info info, int val, int val2); 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); int (*of_xlate)(struct iio_dev *indio_dev, const struct of_phandle_args *iiospec); int (*hwfifo_set_watermark)(struct iio_dev *indio_dev, unsigned val); int (*hwfifo_flush_to_buffer)(struct iio_dev *indio_dev, unsigned count); }; /** * 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 * @pollfunc_event: [DRIVER] function run on events 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_poll_func *pollfunc_event; 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 }; const struct iio_chan_spec *iio_find_channel_from_si(struct iio_dev *indio_dev, int si); int iio_device_register(struct iio_dev *indio_dev); void iio_device_unregister(struct iio_dev *indio_dev); int devm_iio_device_register(struct device *dev, struct iio_dev *indio_dev); void devm_iio_device_unregister(struct device *dev, struct iio_dev *indio_dev); int iio_push_event(struct iio_dev *indio_dev, u64 ev_code, s64 timestamp); int iio_device_claim_direct_mode(struct iio_dev *indio_dev); void iio_device_release_direct_mode(struct iio_dev *indio_dev); 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 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)); } void iio_device_free(struct iio_dev *indio_dev); int devm_iio_device_match(struct device *dev, void *res, void *data); struct iio_dev *devm_iio_device_alloc(struct device *dev, int sizeof_priv); void devm_iio_device_free(struct device *dev, struct iio_dev *indio_dev); struct iio_trigger *devm_iio_trigger_alloc(struct device *dev, const char *fmt, ...); void devm_iio_trigger_free(struct device *dev, struct iio_trigger *iio_trig); /** * 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 | INDIO_BUFFER_SOFTWARE); } /** * 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 ssize_t iio_format_value(char *buf, unsigned int type, int size, int *vals); 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_RAD_TO_DEGREE() - Convert rad to degree * @rad: A value in rad * * Returns the given value converted from rad to degree */ #define IIO_RAD_TO_DEGREE(rad) \ (((rad) * 18000000ULL + 314159ULL / 2) / 314159ULL) /** * 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) /** * IIO_M_S_2_TO_G() - Convert meter / second**2 to g * @ms2: A value in meter / second**2 * * Returns the given value converted from meter / second**2 to g */ #define IIO_M_S_2_TO_G(ms2) (((ms2) * 100000ULL + 980665ULL / 2) / 980665ULL) #endif /* _INDUSTRIAL_IO_H_ */