[PATCH 0/5] virtio: Parse virtio-device nodes from DT

[PATCH 0/5] virtio: Parse virtio-device nodes from DT

[Viresh Kumar]

Hi,

Currently the DT only provides support for following node types for virtio-mmio
nodes:

	virtio_mmio@a000000 {
		dma-coherent;
		interrupts = <0x00 0x10 0x01>;
		reg = <0x00 0xa000000 0x00 0x200>;
		compatible = "virtio,mmio";
	};

And each virtio-mmio corresponds to a virtio-device. But there is no way for
other users in the DT to show their dependency on virtio devices.

This patchset provides that support.

The first patch update virtio,mmio bindings to allow for device subnodes to be
present and the second patch updates the virtio-mmio driver to update the
of_node.

Other patches add bindings for i2c and gpio virtio devices (they have some
dependencies, mentioned in the patches).

Tested on x86 with qemu for arm64.

--
Viresh

Viresh Kumar (5):
  dt-bindings: virtio: mmio: Add support for device subnode
  virtio_mmio: Bind virtio device to device-tree node
  dt-bindings: i2c: Add bindings for i2c-virtio
  i2c: virtio: Update i2c-adapter's of_node
  dt-bindings: gpio: Add bindings for gpio-virtio

 .../devicetree/bindings/gpio/gpio-virtio.yaml | 67 +++++++++++++++++++
 .../devicetree/bindings/i2c/i2c-virtio.yaml   | 59 ++++++++++++++++
 .../devicetree/bindings/virtio/mmio.yaml      | 41 ++++++++++++
 drivers/i2c/busses/i2c-virtio.c               |  1 +
 drivers/virtio/virtio_mmio.c                  | 44 ++++++++++++
 include/dt-bindings/virtio/virtio_ids.h       |  1 +
 6 files changed, 213 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/gpio-virtio.yaml
 create mode 100644 Documentation/devicetree/bindings/i2c/i2c-virtio.yaml
 create mode 120000 include/dt-bindings/virtio/virtio_ids.h

-- 
2.31.1.272.g89b43f80a514

[PATCH 3/5] dt-bindings: i2c: Add bindings for i2c-virtio

[Viresh Kumar]

i2c-virtio represents a virtio I2C device and this patch adds binding
for the same. The i2c-virtio subnode can be part of a virtio,mmio node
and is based on its binding.

Cc: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 .../devicetree/bindings/i2c/i2c-virtio.yaml   | 59 +++++++++++++++++++
 1 file changed, 59 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/i2c/i2c-virtio.yaml

diff --git a/Documentation/devicetree/bindings/i2c/i2c-virtio.yaml b/Documentation/devicetree/bindings/i2c/i2c-virtio.yaml
new file mode 100644
index 000000000000..6b6538f9a3d8
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-virtio.yaml
@@ -0,0 +1,59 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/i2c-virtio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Virtio memory mapped I2C Adapter
+
+maintainers:
+  - Viresh Kumar <viresh.kumar@linaro.org>
+
+description:
+  Virtio I2C device, see /schemas/virtio/mmio.yaml for more details.
+
+allOf:
+  - $ref: /schemas/i2c/i2c-controller.yaml#
+
+properties:
+  $nodename:
+    pattern: '^i2c-virtio@[0-9]+$'
+
+  reg:
+    description:
+      The cell is the device ID of the I2C device (VIRTIO_ID_I2C_ADAPTER) as per
+      dt-bindings/virtio/virtio_ids.h.
+    const: 34
+    $ref: /schemas/virtio/mmio.yaml#/properties/reg
+
+required:
+  - reg
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/virtio/virtio_ids.h>
+
+    virtio@3000 {
+        compatible = "virtio,mmio";
+        reg = <0x3000 0x100>;
+        interrupts = <41>;
+
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        i2c-virtio@0 {
+            reg = <VIRTIO_ID_I2C_ADAPTER>;
+
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            light-sensor@1c {
+                compatible = "dynaimage,al3320a";
+                reg = <0x20>;
+            };
+        };
+    };
+
+...
-- 
2.31.1.272.g89b43f80a514

Re: [PATCH 3/5] dt-bindings: i2c: Add bindings for i2c-virtio

[Rob Herring]

On Tue, 13 Jul 2021 16:20:32 +0530, Viresh Kumar wrote:
> i2c-virtio represents a virtio I2C device and this patch adds binding
> for the same. The i2c-virtio subnode can be part of a virtio,mmio node
> and is based on its binding.
> 
> Cc: Wolfram Sang <wsa@kernel.org>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---
>  .../devicetree/bindings/i2c/i2c-virtio.yaml   | 59 +++++++++++++++++++
>  1 file changed, 59 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/i2c/i2c-virtio.yaml
> 

My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
on your patch (DT_CHECKER_FLAGS is new in v5.13):

yamllint warnings/errors:

dtschema/dtc warnings/errors:
Unknown file referenced: [Errno 2] No such file or directory: '/usr/local/lib/python3.8/dist-packages/dtschema/schemas/virtio/mmio.yaml'
xargs: dt-doc-validate: exited with status 255; aborting
Documentation/devicetree/bindings/i2c/i2c-virtio.example.dts:19:18: fatal error: dt-bindings/virtio/virtio_ids.h: No such file or directory
   19 |         #include <dt-bindings/virtio/virtio_ids.h>
      |                  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
compilation terminated.
make[1]: *** [scripts/Makefile.lib:380: Documentation/devicetree/bindings/i2c/i2c-virtio.example.dt.yaml] Error 1
make[1]: *** Waiting for unfinished jobs....
make: *** [Makefile:1416: dt_binding_check] Error 2
\ndoc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/patch/1504542

This check can fail if there are any dependencies. The base for a patch
series is generally the most recent rc1.

If you already ran 'make dt_binding_check' and didn't see the above
error(s), then make sure 'yamllint' is installed and dt-schema is up to
date:

pip3 install dtschema --upgrade

Please check and re-submit.

[PATCH 4/5] i2c: virtio: Update i2c-adapter's of_node

[Viresh Kumar]

Set of_node of the adapter from the virtio device to enable automatic
parsing the of the I2C devices present in DT.

Cc: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
Depends on:

https://lore.kernel.org/linux-i2c/984ebecaf697058eb73389ed14ead9dd6d38fb53.1625796246.git.jie.deng@intel.com/
---
 drivers/i2c/busses/i2c-virtio.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/i2c/busses/i2c-virtio.c b/drivers/i2c/busses/i2c-virtio.c
index 0139cdc33cae..cb8cfae2748f 100644
--- a/drivers/i2c/busses/i2c-virtio.c
+++ b/drivers/i2c/busses/i2c-virtio.c
@@ -223,6 +223,7 @@ static int virtio_i2c_probe(struct virtio_device *vdev)
 		 "i2c_virtio at virtio bus %d", vdev->index);
 	vi->adap.algo = &virtio_algorithm;
 	vi->adap.dev.parent = &vdev->dev;
+	vi->adap.dev.of_node = vdev->dev.of_node;
 	i2c_set_adapdata(&vi->adap, vi);
 
 	/*
-- 
2.31.1.272.g89b43f80a514