Merge tag 'iio-for-3.12d' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Fourth round of IIO new drivers, functionality and cleanups for the 3.13 cycle.

New Drivers
* cm36651 combined RGB light and proximity sensor.

Core improvements

* Some more fixes and cleanups related to buffers.  These include the second
  half of a series which went is as fixes.  The basis for delaying until the
  next merge window is that some are too invasive for this late in a cycle
  and others only effect code paths current unused in the mainline tree.
  In this case we have:
   * protecting against concurrent userspace access
   * fixing a memory leak if a device goes away
   * avoiding always reallocating the buffer whether or not it has changed
     (a bug fix, but one with no functional changes other than a small speed
     improvement.)
   * Add reference counting for buffers to ensure they hang around if open
     from userspace or in kernel when the device is forcefully removed.
   * Return -ENODEV for buffer access operations when the device has gone
     away.
   * Add proper locking for iio_update_buffers (currently we only have one
     buffer per device in mainline, but an input bridge driver is under
     development which would make this bug 'real'.)
   * Wake up anyone waiting on a buffer if the device is unregistered.  A
     subsequent read will fail, notifying userspace that the device is no
     longer there rather than having it wait possibly for ever.

* Move the iio_sw_preenable functionality into the core.  This avoids drivers
  having to 'know' about how the buffers are implemented and is called by
  almost all drivers anyway.  Those that don't call it are not harmed by it
  being called.
* New registration approach for information (i.e. sysfs attributes) about
  events.  Much more generic and now similar to how the equivalent is
  handled for channel information.  The events infrastructure had been left
  behind by other changes so this brings it back in line.
* Using the new events registration approach, add a hysterisis event_info
  element and apply this to those drivers with this property.
* A little unitialized variable bug in the generic_buffer.c example.
* Factor out the code for freeing lists of IIO Device attributes to avoid
  some repitition.

Driver cleanups
* At91 driver gains touch screen support and some related fixes.
* Follow up series of patches removing the now redundant
  iio_sw_buffer_preenable calls.
* Lots of conversions to the new event registration methods.
* Another round of hmc5843 cleanups as that driver moves towards graduating
  from staging.
* Make some SoC drivers buildable if COMPILE_TEST is used.  Follow up fixes
  for a few bits and bobs that revealed.
* Add explicit includes of linux/of.h to those drivers making us of linux/of.h

4 files changed, 106 insertions, 16 deletions

diff --git a/include/linux/iio/buffer.h b/include/linux/iio/buffer.h
index a1124bdc4cac..15607b45221a 100644
--- a/include/linux/iio/buffer.h
+++ b/include/linux/iio/buffer.h
@@ -11,6 +11,7 @@
 #define _IIO_BUFFER_GENERIC_H_
 #include <linux/sysfs.h>
 #include <linux/iio/iio.h>
+#include <linux/kref.h>
 
 #ifdef CONFIG_IIO_BUFFER
 
@@ -26,6 +27,8 @@ struct iio_buffer;
  * @set_bytes_per_datum:set number of bytes per datum
  * @get_length:		get number of datums in buffer
  * @set_length:		set number of datums in buffer
+ * @release:		called when the last reference to the buffer is dropped,
+ *			should free all resources allocated by the buffer.
  *
  * The purpose of this structure is to make the buffer element
  * modular as event for a given driver, different usecases may require
@@ -47,6 +50,8 @@ struct iio_buffer_access_funcs {
 	int (*set_bytes_per_datum)(struct iio_buffer *buffer, size_t bpd);
 	int (*get_length)(struct iio_buffer *buffer);
 	int (*set_length)(struct iio_buffer *buffer, int length);
+
+	void (*release)(struct iio_buffer *buffer);
 };
 
 /**
@@ -67,6 +72,7 @@ struct iio_buffer_access_funcs {
  * @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.
+ * @ref:		[INTERN] reference count of the buffer.
  */
 struct iio_buffer {
 	int					length;
@@ -83,6 +89,7 @@ struct iio_buffer {
 	struct list_head			demux_list;
 	void					*demux_bounce;
 	struct list_head			buffer_list;
+	struct kref				ref;
 };
 
 /**
@@ -199,11 +206,27 @@ ssize_t iio_buffer_show_enable(struct device *dev,
 					   iio_buffer_show_enable,	\
 					   iio_buffer_store_enable)
 
-int iio_sw_buffer_preenable(struct iio_dev *indio_dev);
-
 bool iio_validate_scan_mask_onehot(struct iio_dev *indio_dev,
 	const unsigned long *mask);
 
+struct iio_buffer *iio_buffer_get(struct iio_buffer *buffer);
+void iio_buffer_put(struct iio_buffer *buffer);
+
+/**
+ * iio_device_attach_buffer - Attach a buffer to a IIO device
+ * @indio_dev: The device the buffer should be attached to
+ * @buffer: The buffer to attach to the device
+ *
+ * This function attaches a buffer to a IIO device. The buffer stays attached to
+ * the device until the device is freed. The function should only be called at
+ * most once per device.
+ */
+static inline void iio_device_attach_buffer(struct iio_dev *indio_dev,
+	struct iio_buffer *buffer)
+{
+	indio_dev->buffer = iio_buffer_get(buffer);
+}
+
 #else /* CONFIG_IIO_BUFFER */
 
 static inline int iio_buffer_register(struct iio_dev *indio_dev,
@@ -216,6 +239,9 @@ static inline int iio_buffer_register(struct iio_dev *indio_dev,
 static inline void iio_buffer_unregister(struct iio_dev *indio_dev)
 {}
 
+static inline void iio_buffer_get(struct iio_buffer *buffer) {}
+static inline void iio_buffer_put(struct iio_buffer *buffer) {}
+
 #endif /* CONFIG_IIO_BUFFER */
 
 #endif /* _IIO_BUFFER_GENERIC_H_ */
diff --git a/include/linux/iio/events.h b/include/linux/iio/events.h
index 13ce220c7003..5dab2c41031f 100644
--- a/include/linux/iio/events.h
+++ b/include/linux/iio/events.h
@@ -26,20 +26,6 @@ struct iio_event_data {
 
 #define IIO_GET_EVENT_FD_IOCTL _IOR('i', 0x90, int)
 
-enum iio_event_type {
-	IIO_EV_TYPE_THRESH,
-	IIO_EV_TYPE_MAG,
-	IIO_EV_TYPE_ROC,
-	IIO_EV_TYPE_THRESH_ADAPTIVE,
-	IIO_EV_TYPE_MAG_ADAPTIVE,
-};
-
-enum iio_event_direction {
-	IIO_EV_DIR_EITHER,
-	IIO_EV_DIR_RISING,
-	IIO_EV_DIR_FALLING,
-};
-
 /**
  * IIO_EVENT_CODE() - create event identifier
  * @chan_type:	Type of the channel. Should be one of enum iio_chan_type.
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index ac1cb8f1858c..256a90a1bea6 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -139,6 +139,29 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
 }
 
 /**
+ * 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.
@@ -163,6 +186,9 @@ ssize_t iio_enum_write(struct iio_dev *indio_dev,
  * @info_mask_shared_by_all: What information is to be exported that is shared
  *			by all channels.
  * @event_mask:		What events can this channel produce.
+ * @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.
@@ -201,6 +227,8 @@ struct iio_chan_spec {
 	long			info_mask_shared_by_dir;
 	long			info_mask_shared_by_all;
 	long			event_mask;
+	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;
@@ -283,6 +311,12 @@ struct iio_dev;
  *			is event dependant. event_code specifies which event.
  * @write_event_value:	write the value associated with the event.
  *			Meaning is event dependent.
+ * @read_event_config_new: find out if the event is enabled. New style interface.
+ * @write_event_config_new: set if the event is enabled. New style interface.
+ * @read_event_value_new: read a configuration value associated with the event.
+ *                         New style interface.
+ * @write_event_value_new: write a configuration value for the event. New style
+ *			   interface.
  * @validate_trigger:	function to validate the trigger when the
  *			current trigger gets changed.
  * @update_scan_mode:	function to configure device and scan buffer when
@@ -323,6 +357,30 @@ struct iio_info {
 	int (*write_event_value)(struct iio_dev *indio_dev,
 				 u64 event_code,
 				 int val);
+
+	int (*read_event_config_new)(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_new)(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_new)(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_new)(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,
diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h
index 88bf0f0d27b4..4ac928ee31c5 100644
--- a/include/linux/iio/types.h
+++ b/include/linux/iio/types.h
@@ -54,6 +54,26 @@ enum iio_modifier {
 	IIO_MOD_LIGHT_BLUE,
 };
 
+enum iio_event_type {
+	IIO_EV_TYPE_THRESH,
+	IIO_EV_TYPE_MAG,
+	IIO_EV_TYPE_ROC,
+	IIO_EV_TYPE_THRESH_ADAPTIVE,
+	IIO_EV_TYPE_MAG_ADAPTIVE,
+};
+
+enum iio_event_info {
+	IIO_EV_INFO_ENABLE,
+	IIO_EV_INFO_VALUE,
+	IIO_EV_INFO_HYSTERESIS,
+};
+
+enum iio_event_direction {
+	IIO_EV_DIR_EITHER,
+	IIO_EV_DIR_RISING,
+	IIO_EV_DIR_FALLING,
+};
+
 #define IIO_VAL_INT 1
 #define IIO_VAL_INT_PLUS_MICRO 2
 #define IIO_VAL_INT_PLUS_NANO 3