Merge tag 'iio-for-6.11b' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jic23/iio into char-misc-next

Jonathan writes:

IIO: 2nd set of new device support, features and cleanup for 6.11

The big one here is we finally have Paul Cercueil's (and others)
DMA buffer support for IIO devices enabling high speed zero
copy transfer of data to and from sensors supported by IIO (and for
example USB).  This should aid with upstream support of a range of
higher performance ADCs and DACs.

Two merges from other trees
- spi/spi_devm_optimize used for simplification in ad7944.
- dmaengine/topic_dma_vec to enable the DMABUF series.

One feature with impact outside IIO.
- Richer set of dev_err_probe() like helpers to cover ERR_PTR() cases.

New device support
==================
adi,ad7173
- Add support for AD4111, AD4112, AD4114, AD4115 and ADC4116 pseudo
  differential ADCs. Major driver rework was needed to enabled these.
adi,ad7944
- Use devm_spi_optimize_message() to avoid a local devm cleanup
  callback. This is the example case from the patch set, others will
  follow.
mediatek,mt6359-auxadc
- New driver for this ADC IP found in MT6357, MT6358 and MT6359 PMICs.
st,accel
- Add support for the LIS2DS12 accelerometer
ti,ads1119
- New driver for this 16 bit 2-differential or 4-single ended channel
  ADC.

Features
========
dt-bindings
- Introduce new common-mode-channel property to help handle pseudo
  differential ADCs where we have something that looks like one side
  of differential input, but which is only suited for use with a
  slow moving reference.
adi,adf4350
- Support use as a clock provider.
iio-hmwon
- Support reading of labels from IIO devices by their consumers and
  use this in the hwmon bridge.

Cleanup and minor fixes
=======================
Treewide
- Use regmap_clear_bits() / regmap_set_bits() to simplify open coded
  equivalents.
- Use devm_regulator_get_enable_read_voltage() to replace equivalent
  opencoded boilerplate. In some cases enabled complete conversion to
  devm handling and removal of explicit remove() callbacks.
- Introduce dev_err_ptr_probe() and other variants and make use of
  of them in a couple of examples driver cleanups. Will find use in
  many more drivers soon.
adi,ad7192
- Introduce local struct device *dev and use dev_err_probe() to give
  more readable code.
adi,adi-axi-adc/dac
- Improved consistency of messages using dev_err_probe()
adi,adis
- Split the trigger handling into cases that needed paging and those that
  don't resulting in more readable code.
- Use cleanup.h to simplify error paths via scoped cleanup.
- Add adis specific lock helpers and make use of them in a number of drivers.
adi,ad7192
- Update maintainer (Alisa-Dariana Roman)
adi,ad7606
- dt-binding cleanup.
avago,apds9306
- Add a maintainer entry (Subhajit Ghosh)
linear,ltc2309
- Fix a wrong endian type.
st,stm32-dfsdm
- Fix a missing port property in the dt-binding.
st,sensors
- Relax whoami match failure to a warning print rather than probe failure.
  This enables fallback compatibles to existing parts from those that don't
  necessarily even exit yet.

* tag 'iio-for-6.11b' of ssh://gitolite.kernel.org/pub/scm/linux/kernel/git/jic23/iio: (112 commits)
  iio: adc: ad7173: Fix uninitialized symbol is_current_chan
  iio: adc: Add support for MediaTek MT6357/8/9 Auxiliary ADC
  math.h: Add unsigned 8 bits fractional numbers type
  dt-bindings: iio: adc: Add MediaTek MT6359 PMIC AUXADC
  iio: common: scmi_iio: convert to dev_err_probe()
  iio: backend: make use of dev_err_cast_probe()
  iio: temperature: ltc2983: convert to dev_err_probe()
  dev_printk: add new dev_err_probe() helpers
  iio: xilinx-ams: Add labels
  iio: adc: ad7944: use devm_spi_optimize_message()
  Documentation: iio: Document high-speed DMABUF based API
  iio: buffer-dmaengine: Support new DMABUF based userspace API
  iio: buffer-dma: Enable support for DMABUFs
  iio: core: Add new DMABUF interface infrastructure
  MAINTAINERS: Update AD7192 driver maintainer
  iio: adc: ad7192: use devm_regulator_get_enable_read_voltage
  iio: st_sensors: relax WhoAmI check in st_sensors_verify_id()
  MAINTAINERS: Add AVAGO APDS9306
  dt-bindings: iio: adc: adi,ad7606: comment and sort the compatible names
  dt-bindings: iio: adc: adi,ad7606: add missing datasheet link
  ...

13 files changed, 482 insertions, 4 deletions

diff --git a/Documentation/devicetree/bindings/iio/adc/adc.yaml b/Documentation/devicetree/bindings/iio/adc/adc.yaml
index 0a77592f7388..8e7835cf36fd 100644
--- a/Documentation/devicetree/bindings/iio/adc/adc.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adc.yaml
@@ -46,6 +46,17 @@ properties:
       differential channels). If this and diff-channels are not present reg
       shall be used instead.
 
+  common-mode-channel:
+    $ref: /schemas/types.yaml#/definitions/uint32
+    description:
+      Some ADCs have differential input pins that can be used to measure
+      single-ended or pseudo-differential inputs. This property can be used
+      in addition to single-channel to signal software that this channel is
+      not differential but still specify two inputs.
+
+      The input pair is specified by setting single-channel to the positive
+      input pin and common-mode-channel to the negative pin.
+
   settling-time-us:
     description:
       Time between enabling the channel and first stable readings.
diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
index ea6cfcd0aff4..17c5d39cc2c1 100644
--- a/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7173.yaml
@@ -19,7 +19,18 @@ description: |
   primarily for measurement of signals close to DC but also delivers
   outstanding performance with input bandwidths out to ~10kHz.
 
+  Analog Devices AD411x ADC's:
+  The AD411X family encompasses a series of low power, low noise, 24-bit,
+  sigma-delta analog-to-digital converters that offer a versatile range of
+  specifications. They integrate an analog front end suitable for processing
+  fully differential/single-ended and bipolar voltage inputs.
+
   Datasheets for supported chips:
+    https://www.analog.com/media/en/technical-documentation/data-sheets/AD4111.pdf
+    https://www.analog.com/media/en/technical-documentation/data-sheets/AD4112.pdf
+    https://www.analog.com/media/en/technical-documentation/data-sheets/AD4114.pdf
+    https://www.analog.com/media/en/technical-documentation/data-sheets/AD4115.pdf
+    https://www.analog.com/media/en/technical-documentation/data-sheets/AD4116.pdf
     https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-2.pdf
     https://www.analog.com/media/en/technical-documentation/data-sheets/AD7172-4.pdf
     https://www.analog.com/media/en/technical-documentation/data-sheets/AD7173-8.pdf
@@ -31,6 +42,11 @@ description: |
 properties:
   compatible:
     enum:
+      - adi,ad4111
+      - adi,ad4112
+      - adi,ad4114
+      - adi,ad4115
+      - adi,ad4116
       - adi,ad7172-2
       - adi,ad7172-4
       - adi,ad7173-8
@@ -129,10 +145,56 @@ patternProperties:
         maximum: 15
 
       diff-channels:
+        description: |
+          This property is used for defining the inputs of a differential
+          voltage channel. The first value is the positive input and the second
+          value is the negative input of the channel.
+
+          Family AD411x supports a dedicated VINCOM voltage input.
+          To select it set the second channel to 16.
+            (VIN2, VINCOM) -> diff-channels = <2 16>
+
+          There are special values that can be selected besides the voltage
+          analog inputs:
+            21: REF+
+            22: REF−
+
+          Supported only by AD7172-2, AD7172-4, AD7175-2, AD7175-8, AD7177-2,
+          must be paired together and can be used to monitor the power supply
+          of the ADC:
+            19: ((AVDD1 − AVSS)/5)+
+            20: ((AVDD1 − AVSS)/5)−
+
         items:
           minimum: 0
           maximum: 31
 
+      single-channel:
+        description: |
+          This property is used for defining a current channel or the positive
+          input of a voltage channel (single-ended or pseudo-differential).
+
+          Models AD4111 and AD4112 support current channels.
+            Example: (IIN2+, IIN2−) -> single-channel = <2>
+          To correctly configure a current channel set the "adi,current-channel"
+          property to true.
+
+          To configure a single-ended/pseudo-differential channel set the
+          "common-mode-channel" property to the desired negative voltage input.
+
+          When used as a voltage channel, special inputs are valid as well.
+        minimum: 0
+        maximum: 31
+
+      common-mode-channel:
+        description:
+          This property is used for defining the negative input of a
+          single-ended or pseudo-differential voltage channel.
+
+          Special inputs are valid as well.
+        minimum: 0
+        maximum: 31
+
       adi,reference-select:
         description: |
           Select the reference source to use when converting on
@@ -154,9 +216,31 @@ patternProperties:
           - avdd
         default: refout-avss
 
+      adi,current-channel:
+        $ref: /schemas/types.yaml#/definitions/flag
+        description: |
+          Signal that the selected inputs are current channels.
+          Only available on AD4111 and AD4112.
+
     required:
       - reg
-      - diff-channels
+
+    allOf:
+      - oneOf:
+          - required: [single-channel]
+            properties:
+              diff-channels: false
+          - required: [diff-channels]
+            properties:
+              single-channel: false
+              adi,current-channel: false
+              common-mode-channel: false
+
+      - if:
+          required: [common-mode-channel]
+        then:
+          properties:
+            adi,current-channel: false
 
 required:
   - compatible
@@ -166,7 +250,6 @@ allOf:
   - $ref: /schemas/spi/spi-peripheral-props.yaml#
 
   # Only ad7172-4, ad7173-8 and ad7175-8 support vref2
-  # Other models have [0-3] channel registers
   - if:
       properties:
         compatible:
@@ -187,6 +270,37 @@ allOf:
                 - vref
                 - refout-avss
                 - avdd
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - adi,ad4114
+              - adi,ad4115
+              - adi,ad4116
+              - adi,ad7173-8
+              - adi,ad7175-8
+    then:
+      patternProperties:
+        "^channel@[0-9a-f]$":
+          properties:
+            reg:
+              maximum: 15
+
+  - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - adi,ad7172-2
+              - adi,ad7175-2
+              - adi,ad7176-2
+              - adi,ad7177-2
+    then:
+      patternProperties:
+        "^channel@[0-9a-f]$":
+          properties:
             reg:
               maximum: 3
 
@@ -211,6 +325,34 @@ allOf:
             - adi,reference-select
 
   - if:
+      properties:
+        compatible:
+          contains:
+            enum:
+              - adi,ad4111
+              - adi,ad4112
+              - adi,ad4114
+              - adi,ad4115
+              - adi,ad4116
+    then:
+      properties:
+        avdd2-supply: false
+
+  - if:
+      properties:
+        compatible:
+          not:
+            contains:
+              enum:
+                - adi,ad4111
+                - adi,ad4112
+    then:
+      patternProperties:
+        "^channel@[0-9a-f]$":
+          properties:
+            adi,current-channel: false
+
+  - if:
       anyOf:
         - required: [clock-names]
         - required: [clocks]
@@ -221,6 +363,7 @@ allOf:
 unevaluatedProperties: false
 
 examples:
+  # Example AD7173-8 with external reference connected to REF+/REF-:
   - |
     #include <dt-bindings/gpio/gpio.h>
     #include <dt-bindings/interrupt-controller/irq.h>
@@ -277,3 +420,50 @@ examples:
         };
       };
     };
+
+  # Example AD4111 with current channel and single-ended channel:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    spi {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+       adc@0 {
+        compatible = "adi,ad4111";
+        reg = <0>;
+
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
+        interrupt-names = "rdy";
+        interrupt-parent = <&gpio>;
+        spi-max-frequency = <5000000>;
+        gpio-controller;
+        #gpio-cells = <2>;
+        #clock-cells = <0>;
+
+        channel@0 {
+          reg = <0>;
+          bipolar;
+          diff-channels = <4 5>;
+        };
+
+        // Single ended channel VIN2/VINCOM
+        channel@1 {
+          reg = <1>;
+          bipolar;
+          single-channel = <2>;
+          common-mode-channel = <16>;
+        };
+
+        // Current channel IN2+/IN2-
+        channel@2 {
+          reg = <2>;
+          single-channel = <2>;
+          adi,current-channel;
+        };
+      };
+    };
diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml
index 7fa46df1f4fb..00fdaed11cbd 100644
--- a/Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/adi,ad7606.yaml
@@ -11,6 +11,7 @@ maintainers:
 
 description: |
   Analog Devices AD7606 Simultaneous Sampling ADC
+  https://www.analog.com/media/en/technical-documentation/data-sheets/AD7605-4.pdf
   https://www.analog.com/media/en/technical-documentation/data-sheets/ad7606_7606-6_7606-4.pdf
   https://www.analog.com/media/en/technical-documentation/data-sheets/AD7606B.pdf
   https://www.analog.com/media/en/technical-documentation/data-sheets/AD7616.pdf
@@ -19,9 +20,9 @@ properties:
   compatible:
     enum:
       - adi,ad7605-4
-      - adi,ad7606-8
-      - adi,ad7606-6
       - adi,ad7606-4
+      - adi,ad7606-6
+      - adi,ad7606-8  # Referred to as AD7606 (without -8) in the datasheet
       - adi,ad7606b
       - adi,ad7616
 
diff --git a/Documentation/devicetree/bindings/iio/adc/mediatek,mt6359-auxadc.yaml b/Documentation/devicetree/bindings/iio/adc/mediatek,mt6359-auxadc.yaml
new file mode 100644
index 000000000000..6497c416094d
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/mediatek,mt6359-auxadc.yaml
@@ -0,0 +1,33 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/mediatek,mt6359-auxadc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek MT6350 series PMIC AUXADC
+
+maintainers:
+  - AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
+
+description:
+  The Auxiliary Analog/Digital Converter (AUXADC) is an ADC found
+  in some MediaTek PMICs, performing various PMIC related measurements
+  such as battery and PMIC internal voltage regulators temperatures,
+  accessory detection resistance (usually, for a 3.5mm audio jack)
+  other than voltages for various PMIC internal components.
+
+properties:
+  compatible:
+    enum:
+      - mediatek,mt6357-auxadc
+      - mediatek,mt6358-auxadc
+      - mediatek,mt6359-auxadc
+
+  "#io-channel-cells":
+    const: 1
+
+required:
+  - compatible
+  - "#io-channel-cells"
+
+additionalProperties: false
diff --git a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml
index c1b1324fa132..2722edab1d9a 100644
--- a/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml
+++ b/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml
@@ -246,6 +246,10 @@ patternProperties:
                     From common IIO binding. Used to pipe external sigma delta
                     modulator or internal ADC output to DFSDM channel.
 
+                port:
+                  $ref: /schemas/sound/audio-graph-port.yaml#
+                  unevaluatedProperties: false
+
               required:
                 - compatible
                 - "#sound-dai-cells"
diff --git a/Documentation/devicetree/bindings/iio/adc/ti,ads1119.yaml b/Documentation/devicetree/bindings/iio/adc/ti,ads1119.yaml
new file mode 100644
index 000000000000..ba6850ab1f90
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/adc/ti,ads1119.yaml
@@ -0,0 +1,155 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/adc/ti,ads1119.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Texas Instruments ADS1119 ADC
+
+maintainers:
+  - João Paulo Gonçalves <jpaulo.silvagoncalves@gmail.com>
+
+description:
+  The TI ADS1119 is a precision 16-bit ADC over I2C that offers single-ended and
+  differential measurements using a multiplexed input. It features a programmable
+  gain, a programmable sample rate, an internal oscillator and voltage reference,
+  and a 50/60Hz rejection filter.
+
+properties:
+  compatible:
+    const: ti,ads1119
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  reset-gpios:
+    maxItems: 1
+
+  avdd-supply: true
+  dvdd-supply: true
+
+  vref-supply:
+    description:
+      ADC external reference voltage (VREF).
+
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 0
+
+  "#io-channel-cells":
+    const: 1
+
+required:
+  - compatible
+  - reg
+  - "#address-cells"
+  - "#size-cells"
+  - avdd-supply
+  - dvdd-supply
+
+patternProperties:
+  "^channel@([0-6])$":
+    $ref: adc.yaml
+    type: object
+    properties:
+      reg:
+        minimum: 0
+        maximum: 6
+
+      diff-channels:
+        description:
+          Differential input channels AIN0-AIN1, AIN2-AIN3 and AIN1-AIN2.
+        oneOf:
+          - items:
+              - const: 0
+              - const: 1
+          - items:
+              - const: 2
+              - const: 3
+          - items:
+              - const: 1
+              - const: 2
+
+      single-channel:
+        description:
+          Single-ended input channels AIN0, AIN1, AIN2 and AIN3.
+        minimum: 0
+        maximum: 3
+
+    oneOf:
+      - required:
+          - diff-channels
+      - required:
+          - single-channel
+
+    required:
+      - reg
+
+    unevaluatedProperties: false
+
+additionalProperties: false
+
+examples:
+  - |
+
+    #include <dt-bindings/gpio/gpio.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c {
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        adc@40 {
+            compatible = "ti,ads1119";
+            reg = <0x40>;
+            interrupt-parent = <&gpio1>;
+            interrupts = <25 IRQ_TYPE_EDGE_FALLING>;
+            reset-gpios = <&gpio1 10 GPIO_ACTIVE_LOW>;
+            avdd-supply = <&reg_avdd_ads1119>;
+            dvdd-supply = <&reg_dvdd_ads1119>;
+            vref-supply = <&reg_vref_ads1119>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+            #io-channel-cells = <1>;
+
+            channel@0 {
+                reg = <0>;
+                single-channel = <0>;
+            };
+
+            channel@1 {
+                reg = <1>;
+                diff-channels = <0 1>;
+            };
+
+            channel@2 {
+                reg = <2>;
+                single-channel = <3>;
+            };
+
+            channel@3 {
+                reg = <3>;
+                single-channel = <1>;
+            };
+
+            channel@4 {
+                reg = <4>;
+                single-channel = <2>;
+            };
+
+            channel@5 {
+                reg = <5>;
+                diff-channels = <1 2>;
+            };
+
+            channel@6 {
+                reg = <6>;
+                diff-channels = <2 3>;
+            };
+        };
+    };
diff --git a/Documentation/devicetree/bindings/iio/frequency/adi,adf4350.yaml b/Documentation/devicetree/bindings/iio/frequency/adi,adf4350.yaml
index 43cbf27114c7..d1d1311332f8 100644
--- a/Documentation/devicetree/bindings/iio/frequency/adi,adf4350.yaml
+++ b/Documentation/devicetree/bindings/iio/frequency/adi,adf4350.yaml
@@ -28,6 +28,12 @@ properties:
   clock-names:
     const: clkin
 
+  '#clock-cells':
+    const: 0
+
+  clock-output-names:
+    maxItems: 1
+
   gpios:
     maxItems: 1
     description: Lock detect GPIO.
diff --git a/Documentation/devicetree/bindings/iio/st,st-sensors.yaml b/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
index fff7e3d83a02..71c1ee33a393 100644
--- a/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
+++ b/Documentation/devicetree/bindings/iio/st,st-sensors.yaml
@@ -26,6 +26,7 @@ properties:
           - st,lis2dw12
           - st,lis2hh12
           - st,lis2dh12-accel
+          - st,lis2ds12
           - st,lis302dl
           - st,lis331dl-accel
           - st,lis331dlh-accel
diff --git a/Documentation/driver-api/dmaengine/client.rst b/Documentation/driver-api/dmaengine/client.rst
index ecf139f73da4..d491e385d61a 100644
--- a/Documentation/driver-api/dmaengine/client.rst
+++ b/Documentation/driver-api/dmaengine/client.rst
@@ -80,6 +80,10 @@ The details of these operations are:
 
   - slave_sg: DMA a list of scatter gather buffers from/to a peripheral
 
+  - peripheral_dma_vec: DMA an array of scatter gather buffers from/to a
+    peripheral. Similar to slave_sg, but uses an array of dma_vec
+    structures instead of a scatterlist.
+
   - dma_cyclic: Perform a cyclic DMA operation from/to a peripheral till the
     operation is explicitly stopped.
 
@@ -102,6 +106,11 @@ The details of these operations are:
 		unsigned int sg_len, enum dma_data_direction direction,
 		unsigned long flags);
 
+     struct dma_async_tx_descriptor *dmaengine_prep_peripheral_dma_vec(
+		struct dma_chan *chan, const struct dma_vec *vecs,
+		size_t nents, enum dma_data_direction direction,
+		unsigned long flags);
+
      struct dma_async_tx_descriptor *dmaengine_prep_dma_cyclic(
 		struct dma_chan *chan, dma_addr_t buf_addr, size_t buf_len,
 		size_t period_len, enum dma_data_direction direction);
diff --git a/Documentation/driver-api/dmaengine/provider.rst b/Documentation/driver-api/dmaengine/provider.rst
index ceac2a300e32..3085f8b460fa 100644
--- a/Documentation/driver-api/dmaengine/provider.rst
+++ b/Documentation/driver-api/dmaengine/provider.rst
@@ -433,6 +433,12 @@ supported.
     - residue: Provides the residue bytes of the transfer for those that
       support residue.
 
+- ``device_prep_peripheral_dma_vec``
+
+  - Similar to ``device_prep_slave_sg``, but it takes a pointer to a
+    array of ``dma_vec`` structures, which (in the long run) will replace
+    scatterlists.
+
 - ``device_issue_pending``
 
   - Takes the first transaction descriptor in the pending queue,
@@ -544,6 +550,10 @@ dma_cookie_t
 - Not really relevant any more since the introduction of ``virt-dma``
   that abstracts it away.
 
+dma_vec
+
+- A small structure that contains a DMA address and length.
+
 DMA_CTRL_ACK
 
 - If clear, the descriptor cannot be reused by provider until the
diff --git a/Documentation/driver-api/driver-model/devres.rst b/Documentation/driver-api/driver-model/devres.rst
index 18caebad7376..ac9ee7441887 100644
--- a/Documentation/driver-api/driver-model/devres.rst
+++ b/Documentation/driver-api/driver-model/devres.rst
@@ -464,7 +464,10 @@ SLAVE DMA ENGINE
 SPI
   devm_spi_alloc_master()
   devm_spi_alloc_slave()
+  devm_spi_optimize_message()
   devm_spi_register_controller()
+  devm_spi_register_host()
+  devm_spi_register_target()
 
 WATCHDOG
   devm_watchdog_register_device()
diff --git a/Documentation/iio/iio_dmabuf_api.rst b/Documentation/iio/iio_dmabuf_api.rst
new file mode 100644
index 000000000000..2836cadbd495
--- /dev/null
+++ b/Documentation/iio/iio_dmabuf_api.rst
@@ -0,0 +1,54 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+===================================
+High-speed DMABUF interface for IIO
+===================================
+
+1. Overview
+===========
+
+The Industrial I/O subsystem supports access to buffers through a
+file-based interface, with read() and write() access calls through the
+IIO device's dev node.
+
+It additionally supports a DMABUF based interface, where the userspace
+can attach DMABUF objects (externally created) to an IIO buffer, and
+subsequently use them for data transfers.
+
+A userspace application can then use this interface to share DMABUF
+objects between several interfaces, allowing it to transfer data in a
+zero-copy fashion, for instance between IIO and the USB stack.
+
+The userspace application can also memory-map the DMABUF objects, and
+access the sample data directly. The advantage of doing this vs. the
+read() interface is that it avoids an extra copy of the data between the
+kernel and userspace. This is particularly useful for high-speed devices
+which produce several megabytes or even gigabytes of data per second.
+It does however increase the userspace-kernelspace synchronization
+overhead, as the DMA_BUF_SYNC_START and DMA_BUF_SYNC_END IOCTLs have to
+be used for data integrity.
+
+2. User API
+===========
+
+As part of this interface, three new IOCTLs have been added. These three
+IOCTLs have to be performed on the IIO buffer's file descriptor, which
+can be obtained using the IIO_BUFFER_GET_FD_IOCTL() ioctl.
+
+  ``IIO_BUFFER_DMABUF_ATTACH_IOCTL(int fd)``
+    Attach the DMABUF object, identified by its file descriptor, to the
+    IIO buffer. Returns zero on success, and a negative errno value on
+    error.
+
+  ``IIO_BUFFER_DMABUF_DETACH_IOCTL(int fd)``
+    Detach the given DMABUF object, identified by its file descriptor,
+    from the IIO buffer. Returns zero on success, and a negative errno
+    value on error.
+
+    Note that closing the IIO buffer's file descriptor will
+    automatically detach all previously attached DMABUF objects.
+
+  ``IIO_BUFFER_DMABUF_ENQUEUE_IOCTL(struct iio_dmabuf *iio_dmabuf)``
+    Enqueue a previously attached DMABUF object to the buffer queue.
+    Enqueued DMABUFs will be read from (if output buffer) or written to
+    (if input buffer) as long as the buffer is enabled.
diff --git a/Documentation/iio/index.rst b/Documentation/iio/index.rst
index 4c13bfa2865c..9cb4c50cb20d 100644
--- a/Documentation/iio/index.rst
+++ b/Documentation/iio/index.rst
@@ -9,6 +9,7 @@ Industrial I/O
 
    iio_configfs
    iio_devbuf
+   iio_dmabuf_api
    iio_tools
 
 Industrial I/O Kernel Drivers