[PATCH v7 0/8] Introduce HDP support for STM32MP platforms

[Clément Le Goffic]

This patch series introduces the Hardware Debug Port (HDP) support for
STM32MP platforms.

It includes updates to the mmio gpio driver, the addition of device tree
bindings, the HDP driver, and updates to the device tree files for
STM32MP13, STM32MP15,
and STM32MP25 SoCs.
The series also updates the MAINTAINERS file to include myself as the
maintainer for the STM32 HDP driver and adds the necessary
pinmux configurations for HDP pins on STM32MP157C-DK2 as example.

Signed-off-by: Clément Le Goffic <clement.legoffic at foss.st.com>
---
Changes in v7:
- Due to reorganisation, my contract with ST ends at the end of this month
  and I will no longer have access to this mailbox.
  Therefore, I will be available for any mission related to embedded and
  kernel linux.
  Change email address in MAINTAINERS file for STM32 HDP driver
- Link to v6: https://lore.kernel.org/r/20250623-hdp-upstream-v6-0-387536f08398@foss.st.com

Changes in v6:
- Add Krzysztof Kozlowski's 'Reviewd-by' trailer on bindings.
- Remove gpio mmio patch as taken by Bartosz Golaszewski:
  https://lore.kernel.org/all/175031700235.8154.11042956002137082224.b4-ty@linaro.org/
- Link to v5: https://lore.kernel.org/r/20250613-hdp-upstream-v5-0-6fd6f0dc527c@foss.st.com

Changes in v5:
- (Better) Change the bindings file name:
  's/st,stm32-pinctrl-hdp.yaml/st,stm32-hdp.yaml/g'
- Remove Krzysztof Kozlowski's 'Reviewed-by' trailer on bindings.
- Add Linus Walleij's 'Reviewed-by' trailers.
- Refine SoC dtsi patch's commit message to explain the need of keeping
  the HDP node disabled.
- Link to v4: https://lore.kernel.org/r/20250528-hdp-upstream-v4-0-7e9b3ad2036d@foss.st.com

Changes in v4:
- 's/Add/add/g' in MAINTAINERS commit message.
- Fix the (wrong) status update for the thermal node in stm32mp131.dtsi
  file.
- Do not enable HDP by default during compile testing.
- Change the bindings file name:
  's/st,stm32-pinctrl-hdp.yaml/st,stm32-hdp.yaml/g'
- Add Krzysztof Kozlowski's 'Reviewd-by' trailer on bindings.
- Link to v3: https://lore.kernel.org/r/20250523-hdp-upstream-v3-0-bd6ca199466a@foss.st.com

Changes in v3:
- Use `bgpio_init()` function:
    - Add add patch to create the `BGPIOF_NO_INPUT` flag needed for the
     `bgpio_setup_direction()` used in `bgpio_init()`
    - Remove `stm32_hdp_gpio_get` and `stm32_hdp_gpio_set`
- Use `static` pm ops
- Update bindings:
    - add pattern instruction for pin values
    - remove function's maxItems to use `function: true`
    - fix the compatible in the exemples
- Link to v2: https://lore.kernel.org/r/20250520-hdp-upstream-v2-0-53f6b8b5ffc8@foss.st.com

Changes in v2:
- Remove bindings header files with function name as #define
- Add match_data with function name for three compatible:
  "st,stm32mp131-hdp", "st,stm32mp151-hdp" and "st,stm32mp251-hdp".
- Rework a bit the driver to use match_data.
- Remove the use of `dev_err_probe(` in the resume ops.
- Remove `MODULE_ALIAS(`.
- Remove the vertical bar in bindings description paragraph.
- Fix an error in the `pinctrl-0` parameter of the binding example, it
  was refering a node that wasn't existing.
- Use uppercase pin names.
- Link to v1: https://lore.kernel.org/r/20250225-hdp-upstream-v1-0-9d049c65330a@foss.st.com

---
Clément Le Goffic (8):
      dt-bindings: pinctrl: stm32: Introduce HDP
      pinctrl: stm32: Introduce HDP driver
      MAINTAINERS: add Clément Le Goffic as STM32 HDP maintainer
      ARM: dts: stm32: add Hardware debug port (HDP) on stm32mp13
      ARM: dts: stm32: add Hardware debug port (HDP) on stm32mp15
      ARM: dts: stm32: add Hardware debug port (HDP) on stm32mp25
      ARM: dts: stm32: add alternate pinmux for HDP pin and add HDP pinctrl node
      ARM: dts: stm32: add Hardware debug port (HDP) on stm32mp157c-dk2 board

 .../devicetree/bindings/pinctrl/st,stm32-hdp.yaml  | 187 ++++++
 MAINTAINERS                                        |   6 +
 arch/arm/boot/dts/st/stm32mp131.dtsi               |   7 +
 arch/arm/boot/dts/st/stm32mp15-pinctrl.dtsi        |  25 +
 arch/arm/boot/dts/st/stm32mp151.dtsi               |   7 +
 arch/arm/boot/dts/st/stm32mp157c-dk2.dts           |   6 +
 arch/arm64/boot/dts/st/stm32mp251.dtsi             |   7 +
 drivers/pinctrl/stm32/Kconfig                      |  14 +
 drivers/pinctrl/stm32/Makefile                     |   1 +
 drivers/pinctrl/stm32/pinctrl-stm32-hdp.c          | 720 +++++++++++++++++++++
 10 files changed, 980 insertions(+)
---
base-commit: 31b6d25a25ac3fe4ee6092f2bf04a816e4b5b64a
change-id: 20250224-hdp-upstream-622e5da14a9f

Best regards,
--  
Clément Le Goffic <clement.legoffic at foss.st.com>