Merge tag 'iio-for-3.8d' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

IIO cleanups and fixes from Jonathan:

"4th set of IIO driver updates and new functionality for the 3.8 cycle.

2 drivers going through final cleanup and moving out of staging.

Addition to the core of support for multiple buffers from a single
datastream.  This functionality is core in allowing multiple users
of interrupt driven data streams from the devices.  First user
will shortly be an input bridge driver.  This has been in review
/ revision for over a year resulting in a far cleaner result.
Much of the work had been in precursor patches. Here we just
add the buffer set tear up and down support + switch to multiple
buffer pushing in the drivers (a one line change in all users).
Thanks to those who have tested / reviewed this set."

4 files changed, 71 insertions, 5 deletions

diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h
index c629b3a1d9a9..027040569180 100644
--- a/include/linux/iio/buffer.h
+++ b/include/linux/iio/buffer.h
@@ -66,7 +66,8 @@ struct iio_buffer_access_funcs {
  * @stufftoread:	[INTERN] flag to indicate new data.
  * @demux_list:		[INTERN] list of operations required to demux the scan.
  * @demux_bounce:	[INTERN] buffer for doing gather from incoming scan.
- **/
+ * @buffer_list:	[INTERN] entry in the devices list of current buffers.
+ */
 struct iio_buffer {
 	int					length;
 	int					bytes_per_datum;
@@ -81,9 +82,22 @@ struct iio_buffer {
 	const struct attribute_group *attrs;
 	struct list_head			demux_list;
 	unsigned char				*demux_bounce;
+	struct list_head			buffer_list;
 };
 
 /**
+ * iio_update_buffers() - add or remove buffer from active list
+ * @indio_dev:		device to add buffer to
+ * @insert_buffer:	buffer to insert
+ * @remove_buffer:	buffer_to_remove
+ *
+ * Note this will tear down the all buffering and build it up again
+ */
+int iio_update_buffers(struct iio_dev *indio_dev,
+		       struct iio_buffer *insert_buffer,
+		       struct iio_buffer *remove_buffer);
+
+/**
  * iio_buffer_init() - Initialize the buffer structure
  * @buffer:		buffer to be initialized
  **/
@@ -115,11 +129,11 @@ int iio_scan_mask_set(struct iio_dev *indio_dev,
 		      struct iio_buffer *buffer, int bit);
 
 /**
- * iio_push_to_buffer() - push to a registered buffer.
- * @buffer:		IIO buffer structure for device
- * @data:		the data to push to the buffer
+ * iio_push_to_buffers() - push to a registered buffer.
+ * @indio_dev:		iio_dev structure for device.
+ * @data:		Full scan.
  */
-int iio_push_to_buffer(struct iio_buffer *buffer, unsigned char *data);
+int iio_push_to_buffers(struct iio_dev *indio_dev, unsigned char *data);
 
 int iio_update_demux(struct iio_dev *indio_dev);
 
diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h
index e875bcf0478f..126c0a9375f2 100644
--- a/include/linux/iio/consumer.h
+++ b/include/linux/iio/consumer.h
@@ -18,10 +18,12 @@ struct iio_chan_spec;
  * 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;
 };
 
 /**
@@ -59,6 +61,52 @@ struct iio_channel *iio_channel_get_all(const char *name);
  */
 void iio_channel_release_all(struct iio_channel *chan);
 
+struct iio_cb_buffer;
+/**
+ * iio_channel_get_all_cb() - register callback for triggered capture
+ * @name:		Name of 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(const char *name,
+					     int (*cb)(u8 *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.
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index 7806c24e5bc8..adca93a999a7 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -410,6 +410,7 @@ struct iio_buffer_setup_ops {
  *			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
@@ -448,6 +449,7 @@ struct iio_dev {
 	struct iio_event_interface	*event_interface;
 
 	struct iio_buffer		*buffer;
+	struct list_head		buffer_list;
 	int				scan_bytes;
 	struct mutex			mlock;
 
diff --git a/include/linux/iio/machine.h b/include/linux/iio/machine.h
index 809a3f08d5a5..1601a2a63a72 100644
--- a/include/linux/iio/machine.h
+++ b/include/linux/iio/machine.h
@@ -19,11 +19,13 @@
  * @consumer_dev_name:	Name to uniquely identify the consumer device.
  * @consumer_channel:	Unique name used to identify the channel on the
  *			consumer side.
+ * @consumer_data:	Data about the channel for use by the consumer driver.
  */
 struct iio_map {
 	const char *adc_channel_label;
 	const char *consumer_dev_name;
 	const char *consumer_channel;
+	void *consumer_data;
 };
 
 #endif