Merge tag 'iio-for-4.8c' of git://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into staging-next

Jonathan writes:

Third set of IIO new device support, features and cleanups for the 4.8 cycle.

New core features
- Selection of the clock source for IIO timestamps.  This is done per device
  as it makes little sense to have events in one timebase and data timestamped
  on another.  Biggest reason for this is that we currently use a clock
  source which is non monotonic which can result in 'interesting' data sets.
  (Includes export for get_monotonic_corse64 which Thomas Gleixner didn't mind
   in an earlier version.)
- MAINTAINERS add the git tree to the list for IIO.

New device support + a kind of indirect staging graduation.
* Broadcom iproc-static-adc
  - new driver
* mcp4531
  - support for MCP454x, MCP456x, MCP464x and MCP466x potentiometers
* mpu6050
  - support the IC20608 6 axis motion tracking device
* st-sensors
  - support the lis3l02dq + drop the lis3l02dq driver from staging.
  The general purpose driver is missing event support, but good to get
  rid of this driver which was rather long in the tooth.

New driver features
* ak8975
  - Add vid regulator support and refactor handling in general.
  - Allow a delay after enabling regulators.
  - Runtime and system PM.
* bmg160
  - filter frequency control support.
* bmp280
  - SPI device support.
  - EOC interrupt support for the BMP085
  - power management support.
  - supply regulator support.
  - reset gpio support
  - dt bindings for reset gpio and regulators.
  - of table to support device tree registration
* max1363
  - Device tree bindings.
* mcp4531
  - Device tree bindings.
* st-pressure
  - temperature channels as part of triggered buffer (previously not due
  probably to alignment issues - see below).
  - lps22hb open drain interrupt support.
  - lps22hb temperature channel support

Cleanups and reworkings.
* numerous ADC drivers
  - ensure the iio_dev->dev.of_node is set to the parent dev.of_node so
  as to allow client bindings to find the device.
* ak8975
  - Fix incorrect handling of missing regulator
  - make sure power is down and remove.
* bmp280
  - read the calibration data only once as it doesn't change.
* isl29125
  - Use a few macros to make code a touch more readable.
* mma8452
  - fix a memory leak on error.
  - drop an unecessary bit of return value handling.
* potentiometer kconfig
  - typo fix.
* st-pressure
  - drop some uninformative default assignments of elements of the channel
  array structure (aids readability).
* st-sensors
  - Harden interrupt handling considerably.  These are actually all using
  level interrupts, but at least two known boards have them wired to
  edge only interrupt chips.  Hence a slightly interesting bit of handling
  is needed in which we first allow for the easy option (level triggered) and
  secondly check the status registers before reenabling edge interrupts and
  fall back to a tight loop in the thread until we successfully clear the
  interrupt.  No harm is done if we never succeed in doing so.  It's an odd
  patch that has been through a lot of revisions to reach a consensus on how
  to handle what is basically broken hardware (which the previous defaults
  allowed to kind of work).
  - Fix alignment to defined storagebytes boundaries.
  - Ensure alignment of power of 2 byte boundaries.  This has always in theory
  been part of the ABI of IIO, but we missed a few that snuck in that need
  fixing.  The effect was minor as they were only followed by timestamp
  channels which were correctly aligned,
  - Add some docs to explain the gain calculations.

2 files changed, 16 insertions, 8 deletions

diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h
index 28052cddaa03..228bd44efa4c 100644
--- a/include/linux/iio/common/st_sensors.h
+++ b/include/linux/iio/common/st_sensors.h
@@ -223,6 +223,7 @@ struct st_sensor_settings {
  * @get_irq_data_ready: Function to get the IRQ used for data ready signal.
  * @tf: Transfer function structure used by I/O operations.
  * @tb: Transfer buffers and mutex used by I/O operations.
+ * @edge_irq: the IRQ triggers on edges and need special handling.
  * @hw_irq_trigger: if we're using the hardware interrupt on the sensor.
  * @hw_timestamp: Latest timestamp from the interrupt handler, when in use.
  */
@@ -250,6 +251,7 @@ struct st_sensor_data {
 	const struct st_sensor_transfer_function *tf;
 	struct st_sensor_transfer_buffer tb;
 
+	bool edge_irq;
 	bool hw_irq_trigger;
 	s64 hw_timestamp;
 };
diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
index 7c29cb0124ae..854e2dad1e0d 100644
--- a/include/linux/iio/iio.h
+++ b/include/linux/iio/iio.h
@@ -312,13 +312,8 @@ static inline bool iio_channel_has_info(const struct iio_chan_spec *chan,
 		},							\
 }
 
-/**
- * iio_get_time_ns() - utility function to get a time stamp for events etc
- **/
-static inline s64 iio_get_time_ns(void)
-{
-	return ktime_get_real_ns();
-}
+s64 iio_get_time_ns(const struct iio_dev *indio_dev);
+unsigned int iio_get_time_res(const struct iio_dev *indio_dev);
 
 /* Device operating modes */
 #define INDIO_DIRECT_MODE		0x01
@@ -497,6 +492,7 @@ struct iio_buffer_setup_ops {
  * @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
+ * @clock_id:		[INTERN] timestamping clock posix identifier
  * @info_exist_lock:	[INTERN] lock to prevent use during removal
  * @setup_ops:		[DRIVER] callbacks to call before and after buffer
  *			enable/disable
@@ -537,6 +533,7 @@ struct iio_dev {
 	struct attribute_group		chan_attr_group;
 	const char			*name;
 	const struct iio_info		*info;
+	clockid_t			clock_id;
 	struct mutex			info_exist_lock;
 	const struct iio_buffer_setup_ops	*setup_ops;
 	struct cdev			chrdev;
@@ -565,7 +562,7 @@ extern struct bus_type iio_bus_type;
 
 /**
  * iio_device_put() - reference counted deallocation of struct device
- * @indio_dev: 		IIO device structure containing the device
+ * @indio_dev: IIO device structure containing the device
  **/
 static inline void iio_device_put(struct iio_dev *indio_dev)
 {
@@ -574,6 +571,15 @@ static inline void iio_device_put(struct iio_dev *indio_dev)
 }
 
 /**
+ * iio_device_get_clock() - Retrieve current timestamping clock for the device
+ * @indio_dev: IIO device structure containing the device
+ */
+static inline clockid_t iio_device_get_clock(const struct iio_dev *indio_dev)
+{
+	return indio_dev->clock_id;
+}
+
+/**
  * dev_to_iio_dev() - Get IIO device struct from a device struct
  * @dev: 		The device embedded in the IIO device
  *