[PATCH v13 0/4] Enable Remote GPIO over RPMSG on i.MX Platform

Shenwei Wang
2026-04-22T21:29:11Z

Support the remote devices on the remote processor via the RPMSG bus on
i.MX platform.

Changes in v13:
- drop the support for legacy NXP firmware.
- remove the fixed_up hooks from the rpmsg gpio driver.
- code cleanup.

Changes in v12:
- Fixed the "underline" warning reported by Randy.

Changes in v11:
- Expand RPMSG for the first time per Shuah's review comment.

Changes in v10:
- Update gpio-rpmsg.rst according to Daniel Baluta's review comments.
- Add a kernel CONFIG for fixed up handlers and only enable it on
i.MX products.
- Fixed bugs reported by kernel test robot.

Changes in v9:
- Reuse the gpio-virtio design for command and IRQ type definitions.
- Remove msg_id, version, and vendor fields from the generic protocol.
- Add fixed-up handlers to support legacy firmware.

Changes in v8:
- Add "depends on REMOTEPROC" in Kconfig to fix the build error reported
by the kernel test robot.
- Move the .rst patch before the .yaml patch.
- Handle the "ngpios" DT property based on Andrew's feedback.

Changes in v7:
- Reworked the driver to use the rpmsg_driver framework instead of
platform_driver, based on feedback from Bjorn and Arnaud.
- Updated gpio-rpmsg.yaml and imx_rproc.yaml according to comments from
Rob and Arnaud.
- Further refinements to gpio-rpmsg.yaml per Arnaud's feedback.

Changes in v6:
- make the driver more generic with the actions below:
rename the driver file to gpio-rpmsg.c
remove the imx related info in the function and variable names
rename the imx_rpmsg.h to rpdev_info.h
create a gpio-rpmsg.yaml and refer it in imx_rproc.yaml
- update the gpio-rpmsg.rst according to the feedback from Andrew and
move the source file to driver-api/gpio
- fix the bug reported by Zhongqiu Han
- remove the I2C related info

Changes in v5:
- move the gpio-rpmsg.rst from admin-guide to staging directory after
discussion with Randy Dunlap.
- add include files with some code improvements per Bartosz's comments.

Changes in v4:
- add a documentation to describe the transport protocol per Andrew's
comments.
- add a new handler to get the gpio direction.

Changes in v3:
- fix various format issue and return value check per Peng 's review
comments.
- add the logic to also populate the subnodes which are not in the
device map per Arnaud's request. (in imx_rproc.c)
- update the yaml per Frank's review comments.

Changes in v2:
- re-implemented the gpio driver per Linus Walleij's feedback by using
GPIOLIB_IRQCHIP helper library.
- fix various format issue per Mathieu/Peng 's review comments.
- update the yaml doc per Rob's feedback

Shenwei Wang (4):
docs: driver-api: gpio: rpmsg gpio driver over rpmsg bus
dt-bindings: remoteproc: imx_rproc: Add "rpmsg" subnode support
gpio: rpmsg: add generic rpmsg GPIO driver
arm64: dts: imx8ulp: Add rpmsg node under imx_rproc

.../devicetree/bindings/gpio/gpio-rpmsg.yaml | 55 ++
.../bindings/remoteproc/fsl,imx-rproc.yaml | 53 ++
Documentation/driver-api/gpio/gpio-rpmsg.rst | 266 ++++++++
Documentation/driver-api/gpio/index.rst | 1 +
arch/arm64/boot/dts/freescale/imx8ulp.dtsi | 25 +
drivers/gpio/Kconfig | 17 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-rpmsg.c | 573 ++++++++++++++++++
8 files changed, 991 insertions(+)
create mode 100644 Documentation/devicetree/bindings/gpio/gpio-rpmsg.yaml
create mode 100644 Documentation/driver-api/gpio/gpio-rpmsg.rst
create mode 100644 drivers/gpio/gpio-rpmsg.c

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2.43.0