Fixed MTP to work with TWRP

include/linux/iio/consumer.h

@@ -0,0 +1,199 @@
+/*
+ * Industrial I/O in kernel consumer interface
+ *
+ * Copyright (c) 2011 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 _IIO_INKERN_CONSUMER_H_
+#define _IIO_INKERN_CONSUMER_H_
+
+#include <linux/types.h>
+#include <linux/iio/types.h>
+
+struct iio_dev;
+struct iio_chan_spec;
+struct device;
+
+/**
+ * struct iio_channel - everything needed for a consumer to use a channel
+ * @indio_dev:		Device on which the channel exists.
+ * @channel:		Full description of the channel.
+ * @data:		Data about the channel used by consumer.
+ */
+struct iio_channel {
+	struct iio_dev *indio_dev;
+	const struct iio_chan_spec *channel;
+	void *data;
+};
+
+/**
+ * iio_channel_get() - get description of all that is needed to access channel.
+ * @dev:		Pointer to consumer device. Device name must match
+ *			the name of the device as provided in the iio_map
+ *			with which the desired provider to consumer mapping
+ *			was registered.
+ * @consumer_channel:	Unique name to identify the channel on the consumer
+ *			side. This typically describes the channels use within
+ *			the consumer. E.g. 'battery_voltage'
+ */
+struct iio_channel *iio_channel_get(struct device *dev,
+				    const char *consumer_channel);
+
+/**
+ * iio_channel_release() - release channels obtained via iio_channel_get
+ * @chan:		The channel to be released.
+ */
+void iio_channel_release(struct iio_channel *chan);
+
+/**
+ * iio_channel_get_all() - get all channels associated with a client
+ * @dev:		Pointer to consumer device.
+ *
+ * Returns an array of iio_channel structures terminated with one with
+ * null iio_dev pointer.
+ * This function is used by fairly generic consumers to get all the
+ * channels registered as having this consumer.
+ */
+struct iio_channel *iio_channel_get_all(struct device *dev);
+
+/**
+ * iio_channel_release_all() - reverse iio_channel_get_all
+ * @chan:		Array of channels to be released.
+ */
+void iio_channel_release_all(struct iio_channel *chan);
+
+struct iio_cb_buffer;
+/**
+ * iio_channel_get_all_cb() - register callback for triggered capture
+ * @dev:		Pointer to client device.
+ * @cb:			Callback function.
+ * @private:		Private data passed to callback.
+ *
+ * NB right now we have no ability to mux data from multiple devices.
+ * So if the channels requested come from different devices this will
+ * fail.
+ */
+struct iio_cb_buffer *iio_channel_get_all_cb(struct device *dev,
+					     int (*cb)(const void *data,
+						       void *private),
+					     void *private);
+/**
+ * iio_channel_release_all_cb() - release and unregister the callback.
+ * @cb_buffer:		The callback buffer that was allocated.
+ */
+void iio_channel_release_all_cb(struct iio_cb_buffer *cb_buffer);
+
+/**
+ * iio_channel_start_all_cb() - start the flow of data through callback.
+ * @cb_buff:		The callback buffer we are starting.
+ */
+int iio_channel_start_all_cb(struct iio_cb_buffer *cb_buff);
+
+/**
+ * iio_channel_stop_all_cb() - stop the flow of data through the callback.
+ * @cb_buff:		The callback buffer we are stopping.
+ */
+void iio_channel_stop_all_cb(struct iio_cb_buffer *cb_buff);
+
+/**
+ * iio_channel_cb_get_channels() - get access to the underlying channels.
+ * @cb_buff:		The callback buffer from whom we want the channel
+ *			information.
+ *
+ * This function allows one to obtain information about the channels.
+ * Whilst this may allow direct reading if all buffers are disabled, the
+ * primary aim is to allow drivers that are consuming a channel to query
+ * things like scaling of the channel.
+ */
+struct iio_channel
+*iio_channel_cb_get_channels(const struct iio_cb_buffer *cb_buffer);
+
+/**
+ * iio_read_channel_raw() - read from a given channel
+ * @chan:		The channel being queried.
+ * @val:		Value read back.
+ *
+ * Note raw reads from iio channels are in adc counts and hence
+ * scale will need to be applied if standard units required.
+ */
+int iio_read_channel_raw(struct iio_channel *chan,
+			 int *val);
+
+/**
+ * iio_read_channel_average_raw() - read from a given channel
+ * @chan:		The channel being queried.
+ * @val:		Value read back.
+ *
+ * Note raw reads from iio channels are in adc counts and hence
+ * scale will need to be applied if standard units required.
+ *
+ * In opposit to the normal iio_read_channel_raw this function
+ * returns the average of multiple reads.
+ */
+int iio_read_channel_average_raw(struct iio_channel *chan, int *val);
+
+/**
+ * iio_read_channel_processed() - read processed value from a given channel
+ * @chan:		The channel being queried.
+ * @val:		Value read back.
+ *
+ * Returns an error code or 0.
+ *
+ * This function will read a processed value from a channel. A processed value
+ * means that this value will have the correct unit and not some device internal
+ * representation. If the device does not support reporting a processed value
+ * the function will query the raw value and the channels scale and offset and
+ * do the appropriate transformation.
+ */
+int iio_read_channel_processed(struct iio_channel *chan, int *val);
+
+/**
+ * iio_get_channel_type() - get the type of a channel
+ * @channel:		The channel being queried.
+ * @type:		The type of the channel.
+ *
+ * returns the enum iio_chan_type of the channel
+ */
+int iio_get_channel_type(struct iio_channel *channel,
+			 enum iio_chan_type *type);
+
+/**
+ * iio_read_channel_scale() - read the scale value for a channel
+ * @chan:		The channel being queried.
+ * @val:		First part of value read back.
+ * @val2:		Second part of value read back.
+ *
+ * Note returns a description of what is in val and val2, such
+ * as IIO_VAL_INT_PLUS_MICRO telling us we have a value of val
+ * + val2/1e6
+ */
+int iio_read_channel_scale(struct iio_channel *chan, int *val,
+			   int *val2);
+
+/**
+ * iio_convert_raw_to_processed() - Converts a raw value to a processed value
+ * @chan:		The channel being queried
+ * @raw:		The raw IIO to convert
+ * @processed:		The result of the conversion
+ * @scale:		Scale factor to apply during the conversion
+ *
+ * Returns an error code or 0.
+ *
+ * This function converts a raw value to processed value for a specific channel.
+ * A raw value is the device internal representation of a sample and the value
+ * returned by iio_read_channel_raw, so the unit of that value is device
+ * depended. A processed value on the other hand is value has a normed unit
+ * according with the IIO specification.
+ *
+ * The scale factor allows to increase the precession of the returned value. For
+ * a scale factor of 1 the function will return the result in the normal IIO
+ * unit for the channel type. E.g. millivolt for voltage channels, if you want
+ * nanovolts instead pass 1000 as the scale factor.
+ */
+int iio_convert_raw_to_processed(struct iio_channel *chan, int raw,
+	int *processed, unsigned int scale);
+
+#endif