Merge tag 'iio-for-6.10a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio into char-misc-next

Jonathan writes:

IIO: 1st set of new device support, features and cleanup for 6.10

The Analog Device team (Paul Cercueil and Nuno Sa) have been working on
improving high speed device handling. They have had some support in their
own tree for many years, so it is great to see them bring it to upstream.
Some of that is seen here, with the first output device using the
IIO dmaengine infrastructure and a new DAC backend FPGA IP driver.
This makes use of a new set of interfaces to allow backend and
front end driver communication in a fashion that in theory at least
allows for a single driver for a given ADC / DAC independent of
the IP to which is being used to deal with the data bus and DMA aspects
of working with these devices. It is early days for this new
generic way of handling split devices, but as it's kernel internals only
we can merrily change anything about it as a wider diversity of devices
show up and we get a better feel for what works.

Alongside the usual set of new drivers and features we have
the automatic cleanup of fwnode_handle_put() which didn't quite make
it in last cycle. The equivalent DT version was merged by Rob Herring
via the DT binding tree and one patch using that in IIO can also be
found in this pull request. Rob has been making extensive use of that
infrastructure in the DT core which is good to see and provides more
evidence this basic approach is useful.

In some cases, the IIO driver was converted over from DT only to
using the generic firmware description handling of property.h
including using the new macros. The general preference for IIO
is to use this more generic handling where possible - a bunch of other
drivers have been converted this cycle as well.

New device support
==================

adi,ad7173
- New driver supporting AD7172-2, AD7172-4 AD7173-9, AD7175-2, AD7175-8,
  AD7176-2 and AD7177-2 ADCs.
- Follow up fix for an accidental use of logic not instead of bitwise.

adi,ad7944
- New driver supporting AD7944, AD7985 and AD7986 pin compatible ADCs.
- Later patch added use of new spi_optimize_message() to reduce overheads
  of setting up a reused message.
- Additional changes later in series reduced code duplication.

adi,ad9739a RF DAC
- New driver for this 14-bit 2.5 GSPS DAC via an LVDS interface.

adi,axi-dac
- Support for this FPGA IP used to send data to high performance DACs over
  an interface such as JESD204B/C or parallel interfaces.  Used in
  conjunction with a DAC driver. The initial user is the ad9739a.
  The dmaengine-buffer needed various changes to make it bidirectional.

avago,apds9306
- New driver for this ambient light sensor.
- Fix much later in this pull for an off by 1 error.

New device IDs
==============

For these at most an ID and a instance of chip specific data was needed.
Always nice to see manufacturers sticking to an existing software interface
for new parts.

allwinner,sun20i
- Add support for h616.
invensense,mpu6050
- Add support for ICM42688
maxim,max30102
- Add compatible for MAX30101
ti,dac5571
- Add compatible for DAC081C081

General
=======

fwnode_handle
- Support for cleanup.h based __free(fwnode_handle)
- Loop macro using this for looping over child nodes without needing to
  call fwnode_handle_put() in ever early exit from the loop.
- Used in:
  * adi,ad3552r
  * adi,ad4130
  * adi,ad5770r
  * adi,ad74413r
  * adi,ad7173
  * adi,adfm2000
  * linear,ltc2688
  * linear,ltc2983
  * maxim,max11410
  * microchip,pac1934
  * qcom,spmi-adc
  * renesas,rz2gl
  * st,ab8500
  * st,stm32 (Fix for failure to set return value precedes this patch,
    providing an example of why enabling direct returns makes bugs
    less likely)
- Conversions to fwnode also using the cleanup logic
  * adi,ad7124
  * adi,ad7292
  * freescale,fsl-imx25-gcq

- Other conversions to fwnode where the new cleanup handling isn't useful
  * adi,ad7192
  * avia,hx711
  * freescale,mma8452
  * nxp,fxls8962af
  * st,spear
  * ti,twl4030

Features
========

adi,adxl345
- Support SPI_3WIRE mode.

adi,ad9944
- Support 3-wire mode, note this isn't normal 3-wire SPI (unlike the
  adxl345 change above), but rather   a wiring scheme where the SPI
  chip select is used to trigger conversions rather than using a
  separate pin.
- Add some device specific documentation, mostly around the various wiring
  schemes.

invensense,mpu6050
- Add Wake on Motion support as an IIO event and as a wake-up source.

linear,ltc2983
- Add vdd-supply.

ti,hdc3020
- Add power management using trigger on demand mode and adding suspend and
  resume handling.
- Use reset GPIO if available.

Cleanup and fixes
================

iio core
- Use the various autocleanup and lock guards from cleanup.h to simplify
  the IIO core.
- Don't set the pointer used for iio_priv() if it is zero sized as that
  points beyond the end of the allocation. No driver actually uses it
  in that case but good to clean this up.

various drivers
- Drop unnecessary casts of other pointer types to void *

docs
- Add missing ABI entry for in_temp_input.

adi,adx345
- General cleanup prior to adding spi-3wire mode.

adi,axi-adc
- Be more flexible and allow minor version changes as these are expected
  to be backwards compatible.

avago,apds9300/9600
- Merge near identical bindings. The drivers are quite different, but
  the bindings can be shared. The apds9306 binding introduced in this
  series uses this shared binding doc as well.
- Add missing vdd-supply
- Update binding to use IRQ_TYPE_LEVEL_LOW instead of 8.

bosch,bmp280
- Organize headers

freescale,fxl-imx25-gcq
- Use devm_ for remaining probe() time setup allowing dropping
  of specific error handling and remove() functions.

infineon,dps310
- Fix handling of negative temperatures
- Bring style of other similar calls inline with the form needed
  for temperatures
- Ensure error handling of regmap calls is consistent within the driver.
- Simplify scale reading logic.

invensense,mpu6050
- Flip logic in binding to exclude devices without i2c-gate instead
  of opting in.  The list is expected to be much shorter as all recent
  devices support this feature.

honeywell,hsc030pa
- Use spi_read() instead of opening coding.

renesas,rcar
- Use device_for_each_child_of_node_scoped() to remove need to manually
  release. Left over from series the rest of which went in during 6.9.

st,ab8500
- Fix naming of function parameters in kernel-doc

* tag 'iio-for-6.10a' of https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (108 commits)
  iio: adc: ti-ads131e08: Use device_for_each_child_node_scoped() to simplify error paths.
  iio: adc: adi-axi-adc: only error out in major version mismatch
  iio: dac: support the ad9739a RF DAC
  iio: dac: add support for AXI DAC IP core
  iio: backend: add new functionality
  dt-bindings: iio: dac: add docs for AD9739A
  dt-bindings: iio: dac: add docs for AXI DAC IP
  iio: buffer-dmaengine: Enable write support
  iio: buffer-dmaengine: Support specifying buffer direction
  iio: buffer-dma: Enable buffer write support
  iio: buffer-dma: Rename iio_dma_buffer_data_available()
  iio: buffer-dma: add iio_dmaengine_buffer_setup()
  iio: pressure: dps310: simplify scale factor reading
  iio: pressure: dps310: consistently check return value of `regmap_read`
  iio: pressure: dps310: introduce consistent error handling
  iio: pressure: dps310: support negative temperature values
  dt-bindings: iio: adc: Add GPADC for Allwinner H616
  iio: dac: ad5755: make use of of_device_id table
  iio: imu: inv_icm42600: add support of ICM-42688-P
  dt-bindings: iio: imu: add icm42688 inside inv_icm42600
  ...

5 files changed, 95 insertions, 7 deletions

diff --git a/include/linux/iio/adc/ad_sigma_delta.h b/include/linux/iio/adc/ad_sigma_delta.h
index 719cf9cc6e1a..383614ebd760 100644
--- a/include/linux/iio/adc/ad_sigma_delta.h
+++ b/include/linux/iio/adc/ad_sigma_delta.h
@@ -48,6 +48,7 @@ struct iio_dev;
  *   be used.
  * @irq_flags: flags for the interrupt used by the triggered buffer
  * @num_slots: Number of sequencer slots
+ * @irq_line: IRQ for reading conversions. If 0, spi->irq will be used
  */
 struct ad_sigma_delta_info {
 	int (*set_channel)(struct ad_sigma_delta *, unsigned int channel);
@@ -62,6 +63,7 @@ struct ad_sigma_delta_info {
 	unsigned int data_reg;
 	unsigned long irq_flags;
 	unsigned int num_slots;
+	int irq_line;
 };
 
 /**
@@ -89,6 +91,7 @@ struct ad_sigma_delta {
 	unsigned int		active_slots;
 	unsigned int		current_slot;
 	unsigned int		num_slots;
+	int		irq_line;
 	bool			status_appended;
 	/* map slots to channels in order to know what to expect from devices */
 	unsigned int		*slots;
diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h
index a6d79381866e..9d144631134d 100644
--- a/include/linux/iio/backend.h
+++ b/include/linux/iio/backend.h
@@ -4,6 +4,7 @@
 
 #include <linux/types.h>
 
+struct iio_chan_spec;
 struct fwnode_handle;
 struct iio_backend;
 struct device;
@@ -15,6 +16,26 @@ enum iio_backend_data_type {
 	IIO_BACKEND_DATA_TYPE_MAX
 };
 
+enum iio_backend_data_source {
+	IIO_BACKEND_INTERNAL_CONTINUOS_WAVE,
+	IIO_BACKEND_EXTERNAL,
+	IIO_BACKEND_DATA_SOURCE_MAX
+};
+
+/**
+ * IIO_BACKEND_EX_INFO - Helper for an IIO extended channel attribute
+ * @_name:	Attribute name
+ * @_shared:	Whether the attribute is shared between all channels
+ * @_what:	Data private to the driver
+ */
+#define IIO_BACKEND_EX_INFO(_name, _shared, _what) {	\
+	.name = (_name),				\
+	.shared = (_shared),				\
+	.read =  iio_backend_ext_info_get,		\
+	.write = iio_backend_ext_info_set,		\
+	.private = (_what),				\
+}
+
 /**
  * struct iio_backend_data_fmt - Backend data format
  * @type:		Data type.
@@ -35,8 +56,13 @@ struct iio_backend_data_fmt {
  * @chan_enable:	Enable one channel.
  * @chan_disable:	Disable one channel.
  * @data_format_set:	Configure the data format for a specific channel.
+ * @data_source_set:	Configure the data source for a specific channel.
+ * @set_sample_rate:	Configure the sampling rate for a specific channel.
  * @request_buffer:	Request an IIO buffer.
  * @free_buffer:	Free an IIO buffer.
+ * @extend_chan_spec:	Extend an IIO channel.
+ * @ext_info_set:	Extended info setter.
+ * @ext_info_get:	Extended info getter.
  **/
 struct iio_backend_ops {
 	int (*enable)(struct iio_backend *back);
@@ -45,10 +71,21 @@ struct iio_backend_ops {
 	int (*chan_disable)(struct iio_backend *back, unsigned int chan);
 	int (*data_format_set)(struct iio_backend *back, unsigned int chan,
 			       const struct iio_backend_data_fmt *data);
+	int (*data_source_set)(struct iio_backend *back, unsigned int chan,
+			       enum iio_backend_data_source data);
+	int (*set_sample_rate)(struct iio_backend *back, unsigned int chan,
+			       u64 sample_rate_hz);
 	struct iio_buffer *(*request_buffer)(struct iio_backend *back,
 					     struct iio_dev *indio_dev);
 	void (*free_buffer)(struct iio_backend *back,
 			    struct iio_buffer *buffer);
+	int (*extend_chan_spec)(struct iio_backend *back,
+				struct iio_chan_spec *chan);
+	int (*ext_info_set)(struct iio_backend *back, uintptr_t private,
+			    const struct iio_chan_spec *chan,
+			    const char *buf, size_t len);
+	int (*ext_info_get)(struct iio_backend *back, uintptr_t private,
+			    const struct iio_chan_spec *chan, char *buf);
 };
 
 int iio_backend_chan_enable(struct iio_backend *back, unsigned int chan);
@@ -56,10 +93,22 @@ int iio_backend_chan_disable(struct iio_backend *back, unsigned int chan);
 int devm_iio_backend_enable(struct device *dev, struct iio_backend *back);
 int iio_backend_data_format_set(struct iio_backend *back, unsigned int chan,
 				const struct iio_backend_data_fmt *data);
+int iio_backend_data_source_set(struct iio_backend *back, unsigned int chan,
+				enum iio_backend_data_source data);
+int iio_backend_set_sampling_freq(struct iio_backend *back, unsigned int chan,
+				  u64 sample_rate_hz);
 int devm_iio_backend_request_buffer(struct device *dev,
 				    struct iio_backend *back,
 				    struct iio_dev *indio_dev);
+ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t private,
+				 const struct iio_chan_spec *chan,
+				 const char *buf, size_t len);
+ssize_t iio_backend_ext_info_get(struct iio_dev *indio_dev, uintptr_t private,
+				 const struct iio_chan_spec *chan, char *buf);
 
+int iio_backend_extend_chan_spec(struct iio_dev *indio_dev,
+				 struct iio_backend *back,
+				 struct iio_chan_spec *chan);
 void *iio_backend_get_priv(const struct iio_backend *conv);
 struct iio_backend *devm_iio_backend_get(struct device *dev, const char *name);
 struct iio_backend *
diff --git a/include/linux/iio/buffer-dma.h b/include/linux/iio/buffer-dma.h
index 18d3702fa95d..6e27e47077d5 100644
--- a/include/linux/iio/buffer-dma.h
+++ b/include/linux/iio/buffer-dma.h
@@ -132,7 +132,9 @@ int iio_dma_buffer_disable(struct iio_buffer *buffer,
 	struct iio_dev *indio_dev);
 int iio_dma_buffer_read(struct iio_buffer *buffer, size_t n,
 	char __user *user_buffer);
-size_t iio_dma_buffer_data_available(struct iio_buffer *buffer);
+int iio_dma_buffer_write(struct iio_buffer *buffer, size_t n,
+			 const char __user *user_buffer);
+size_t iio_dma_buffer_usage(struct iio_buffer *buffer);
 int iio_dma_buffer_set_bytes_per_datum(struct iio_buffer *buffer, size_t bpd);
 int iio_dma_buffer_set_length(struct iio_buffer *buffer, unsigned int length);
 int iio_dma_buffer_request_update(struct iio_buffer *buffer);
diff --git a/include/linux/iio/buffer-dmaengine.h b/include/linux/iio/buffer-dmaengine.h
index cbb8ba957fad..81d9a19aeb91 100644
--- a/include/linux/iio/buffer-dmaengine.h
+++ b/include/linux/iio/buffer-dmaengine.h
@@ -7,14 +7,28 @@
 #ifndef __IIO_DMAENGINE_H__
 #define __IIO_DMAENGINE_H__
 
+#include <linux/iio/buffer.h>
+
 struct iio_dev;
 struct device;
 
-struct iio_buffer *iio_dmaengine_buffer_alloc(struct device *dev,
-					      const char *channel);
 void iio_dmaengine_buffer_free(struct iio_buffer *buffer);
-int devm_iio_dmaengine_buffer_setup(struct device *dev,
-				    struct iio_dev *indio_dev,
-				    const char *channel);
+struct iio_buffer *iio_dmaengine_buffer_setup_ext(struct device *dev,
+						  struct iio_dev *indio_dev,
+						  const char *channel,
+						  enum iio_buffer_direction dir);
+
+#define iio_dmaengine_buffer_setup(dev, indio_dev, channel)	\
+	iio_dmaengine_buffer_setup_ext(dev, indio_dev, channel,	\
+				       IIO_BUFFER_DIRECTION_IN)
+
+int devm_iio_dmaengine_buffer_setup_ext(struct device *dev,
+					struct iio_dev *indio_dev,
+					const char *channel,
+					enum iio_buffer_direction dir);
+
+#define devm_iio_dmaengine_buffer_setup(dev, indio_dev, channel)	\
+	devm_iio_dmaengine_buffer_setup_ext(dev, indio_dev, channel,	\
+					    IIO_BUFFER_DIRECTION_IN)
 
 #endif
diff --git a/include/linux/property.h b/include/linux/property.h
index 3a1045eb786c..61fc20e5f81f 100644
--- a/include/linux/property.h
+++ b/include/linux/property.h
@@ -13,6 +13,7 @@
 #include <linux/args.h>
 #include <linux/array_size.h>
 #include <linux/bits.h>
+#include <linux/cleanup.h>
 #include <linux/fwnode.h>
 #include <linux/stddef.h>
 #include <linux/types.h>
@@ -174,13 +175,32 @@ struct fwnode_handle *device_get_next_child_node(const struct device *dev,
 	for (child = device_get_next_child_node(dev, NULL); child;	\
 	     child = device_get_next_child_node(dev, child))
 
+#define device_for_each_child_node_scoped(dev, child)			\
+	for (struct fwnode_handle *child __free(fwnode_handle) =	\
+		device_get_next_child_node(dev, NULL);			\
+	     child; child = device_get_next_child_node(dev, child))
+
 struct fwnode_handle *fwnode_get_named_child_node(const struct fwnode_handle *fwnode,
 						  const char *childname);
 struct fwnode_handle *device_get_named_child_node(const struct device *dev,
 						  const char *childname);
 
 struct fwnode_handle *fwnode_handle_get(struct fwnode_handle *fwnode);
-void fwnode_handle_put(struct fwnode_handle *fwnode);
+
+/**
+ * fwnode_handle_put - Drop reference to a device node
+ * @fwnode: Pointer to the device node to drop the reference to.
+ *
+ * This has to be used when terminating device_for_each_child_node() iteration
+ * with break or return to prevent stale device node references from being left
+ * behind.
+ */
+static inline void fwnode_handle_put(struct fwnode_handle *fwnode)
+{
+	fwnode_call_void_op(fwnode, put);
+}
+
+DEFINE_FREE(fwnode_handle, struct fwnode_handle *, fwnode_handle_put(_T))
 
 int fwnode_irq_get(const struct fwnode_handle *fwnode, unsigned int index);
 int fwnode_irq_get_byname(const struct fwnode_handle *fwnode, const char *name);