[PATCH v3 0/2] Add devicetree bindings and maintainer for spi-virtio

[PATCH v3 0/2] Add devicetree bindings and maintainer for spi-virtio

[Francesco Valla]

When a virtio transport exposes a non-discoverable bus, the devicetree
can be used to declare its child devices (if any) and/or other
properties. To allow for that, the virtio framework searches for a node
with a suitable compatible in virtio_device_of_init() when registering
a device [1]; such compatible takes the form "virtio,deviceXX", where
XX is the hexadecimal representation of the virtio device ID as defined
by the virtio specification.

This patchset thus does not introduce a new functionality, but allows
proper validation of nodes tied to spi-virtio devices, aligning SPI to
what is already being done for e.g. I2C and GPIO virtio devices.
It was sent initially as part of a different patchset [2], but since it
complements a functionality that is de-facto already there and is useful
beyond that specific use case it was sent separately (also following the
maintainer's feedback there to separate it from remoteproc-specific
changes).

This was tested both with virtio-mmio using qemu-system-aarch64 and with
remoteproc-virtio with a Zephyr backend (with relevant remoteproc-virtio
parts still not upstreamed - see [2]).

On top of that, I added myself as maintainer for the spi-virtio driver,
since the former maintainer's e-mail bounces back and its owner (Haixu
Cui) did not update it after changing employment.

Thank you!

Regards,
Francesco

[1] https://elixir.bootlin.com/linux/v7.2.8/source/drivers/virtio/virtio.c#L488
[2] https://lore.kernel.org/linux-remoteproc/20260916-remoteproc_virtio_map-v1-0-dac8c5eb4aa9@valla.it/

Signed-off-by: Francesco Valla <francesco@valla.it>
---
Changes in v3:
- Add Francesco as Maintainer of the spi-virtio driver (instead of
  Reviewer) as replacement for the former maintainer (Haixu Cui).
- Link to v2: https://patch.msgid.link/20261027-spi-virtio-bindings-v2-0-67927b24b9d4@valla.it

Changes in v2:
- Expanded the commit message to better explain the functionality and
  the chosen compatible.
- Redundant pieces dropped from bindings.
- Link to v1: https://patch.msgid.link/20260929-spi-virtio-bindings-v1-0-6a0eef3213b3@valla.it

---
Francesco Valla (2):
      dt-bindings: spi: add spi-virtio
      MAINTAINERS: replace spi-virtio maintainer

 .../devicetree/bindings/spi/spi-virtio.yaml        | 46 ++++++++++++++++++++++
 MAINTAINERS                                        |  3 +-
 2 files changed, 48 insertions(+), 1 deletion(-)
---
base-commit: d135ab453a7400a34930bdda1ef4bdc8acfac80e
change-id: 20260927-spi-virtio-bindings-f4e350b2709a

Best regards,
--  
Francesco Valla <francesco@valla.it>

[PATCH v3 1/2] dt-bindings: spi: add spi-virtio

[Francesco Valla]

Add bindings for spi-virtio based on virtio-device, allowing proper
validation of SPI controller nodes declared as children of virtio
transports (e.g.: virtio-mmio). Such nodes are not used to instantiate
devices, which are registered by the virtio transport, but to define
their properties and establish dependencies with other nodes.

The compatible follows what the virtio framework already searches for,
"2d" being the hexadecimal representation of the SPI controller device
ID defined by the virtio specification [1].

[1] https://docs.oasis-open.org/virtio/virtio/v1.4/virtio-v1.4.html

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Francesco Valla <francesco@valla.it>
---
 .../devicetree/bindings/spi/spi-virtio.yaml        | 46 ++++++++++++++++++++++
 MAINTAINERS                                        |  1 +
 2 files changed, 47 insertions(+)

diff --git a/Documentation/devicetree/bindings/spi/spi-virtio.yaml b/Documentation/devicetree/bindings/spi/spi-virtio.yaml
new file mode 100644
index 000000000000..5fc04a9c62cc
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/spi-virtio.yaml
@@ -0,0 +1,46 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/spi-virtio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Virtio SPI controller device
+
+maintainers:
+  - Francesco Valla <francesco@valla.it>
+
+allOf:
+  - $ref: /schemas/spi/spi-controller.yaml#
+  - $ref: /schemas/virtio/virtio-device.yaml#
+
+properties:
+  compatible:
+    const: virtio,device2d
+
+required:
+  - compatible
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    virtio@3000 {
+        compatible = "virtio,mmio";
+        reg = <0x3000 0x100>;
+        interrupts = <41>;
+
+        spi {
+            compatible = "virtio,device2d";
+
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            sram@0 {
+                compatible = "microchip,mchp23k256";
+                reg = <0>;
+                spi-max-frequency = <20000000>;
+            };
+        };
+    };
+
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 03649f08c7c7..5724645bf703 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -29675,6 +29675,7 @@ VIRTIO SPI DRIVER
 M:	Haixu Cui <quic_haixcui@quicinc.com>
 L:	virtualization@lists.linux.dev
 S:	Maintained
+F:	Documentation/devicetree/bindings/spi/spi-virtio.yaml
 F:	drivers/spi/spi-virtio.c
 F:	include/uapi/linux/virtio_spi.h
 

-- 
2.56.0

Re: [PATCH v3 1/2] dt-bindings: spi: add spi-virtio

[sashiko-bot]

> Add bindings for spi-virtio based on virtio-device, allowing proper
> validation of SPI controller nodes declared as children of virtio
> transports (e.g.: virtio-mmio). Such nodes are not used to instantiate
> devices, which are registered by the virtio transport, but to define
> their properties and establish dependencies with other nodes.
> 
> The compatible follows what the virtio framework already searches for,
> "2d" being the hexadecimal representation of the SPI controller device
> ID defined by the virtio specification [1].
> 
> [1] https://docs.oasis-open.org/virtio/virtio/v1.4/virtio-v1.4.html
> 
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
> Signed-off-by: Francesco Valla <francesco@valla.it>

Sashiko has reviewed this patch and found no issues.

-- 
Sashiko AI review · https://sashiko.dev/#/patchset/20261029-spi-virtio-bindings-v3-0-ef30217abefd@valla.it?part=1

[PATCH v3 2/2] MAINTAINERS: replace spi-virtio maintainer

[Francesco Valla]

The e-mail address of the current spi-virtio driver maintainer bounces,
since the owner (Haixu Cui) did not update it after changing employment.
Take over maintainership of the driver, which I am already working on
with the introduction of its devicetree bindings.

Signed-off-by: Francesco Valla <francesco@valla.it>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
---
 MAINTAINERS | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/MAINTAINERS b/MAINTAINERS
index 5724645bf703..c0c12d18401f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -29672,7 +29672,7 @@ F:	include/uapi/linux/virtio_snd.h
 F:	sound/virtio/*
 
 VIRTIO SPI DRIVER
-M:	Haixu Cui <quic_haixcui@quicinc.com>
+M:	Francesco Valla <francesco@valla.it>
 L:	virtualization@lists.linux.dev
 S:	Maintained
 F:	Documentation/devicetree/bindings/spi/spi-virtio.yaml

-- 
2.56.0

Re: [PATCH v3 2/2] MAINTAINERS: replace spi-virtio maintainer

[Krzysztof Kozlowski]

On 29/10/2026 17:27, Francesco Valla wrote:
> The e-mail address of the current spi-virtio driver maintainer bounces,
> since the owner (Haixu Cui) did not update it after changing employment.
> Take over maintainership of the driver, which I am already working on
> with the introduction of its devicetree bindings.
> 
> Signed-off-by: Francesco Valla <francesco@valla.it>
> Acked-by: Michael S. Tsirkin <mst@redhat.com>
> ---

Acked-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>

Best regards,
Krzysztof