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-rw-r--r--include/linux/iio/iio.h492
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diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
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--- /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_ */