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Diffstat (limited to 'include/linux/iio/iio.h')
| -rw-r--r-- | include/linux/iio/iio.h | 492 |
1 files changed, 492 insertions, 0 deletions
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h new file mode 100644 index 000000000000..3a4f6a3ab80d --- /dev/null +++ b/include/linux/iio/iio.h @@ -0,0 +1,492 @@ + +/* 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, +}; + +#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_RAW_SEPARATE_BIT \ + IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_RAW) +#define IIO_CHAN_INFO_PROCESSED_SEPARATE_BIT \ + IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PROCESSED) +#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) +#define IIO_CHAN_INFO_SAMP_FREQ_SEPARATE_BIT \ + IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_SAMP_FREQ) +#define IIO_CHAN_INFO_SAMP_FREQ_SHARED_BIT \ + IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_SAMP_FREQ) +#define IIO_CHAN_INFO_FREQUENCY_SEPARATE_BIT \ + IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_FREQUENCY) +#define IIO_CHAN_INFO_FREQUENCY_SHARED_BIT \ + IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_FREQUENCY) +#define IIO_CHAN_INFO_PHASE_SEPARATE_BIT \ + IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_PHASE) +#define IIO_CHAN_INFO_PHASE_SHARED_BIT \ + IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_PHASE) +#define IIO_CHAN_INFO_HARDWAREGAIN_SEPARATE_BIT \ + IIO_CHAN_INFO_SEPARATE_BIT(IIO_CHAN_INFO_HARDWAREGAIN) +#define IIO_CHAN_INFO_HARDWAREGAIN_SHARED_BIT \ + IIO_CHAN_INFO_SHARED_BIT(IIO_CHAN_INFO_HARDWAREGAIN) + +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_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 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. + * @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 it's 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 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; + 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; +}; + +#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. + **/ +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 + */ +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 + * @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 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 + * @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; + 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 + * @dev: the iio_device 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); +} + +/* 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 + * @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 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); +}; + +/** + * iio_get_debugfs_dentry() - helper function to get the debugfs_dentry + * @indio_dev: IIO device info 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 + +#endif /* _INDUSTRIAL_IO_H_ */ |