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 <redacted>
---
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 (local)

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 (local)

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 (local)

---
Clément Le Goffic (9):
      gpio: mmio: add BGPIOF_NO_INPUT flag for GPO gpiochip
      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/gpio/gpio-mmio.c                           |  11 +-
 drivers/pinctrl/stm32/Kconfig                      |  14 +
 drivers/pinctrl/stm32/Makefile                     |   1 +
 drivers/pinctrl/stm32/pinctrl-stm32-hdp.c          | 720 +++++++++++++++++++++
 include/linux/gpio/driver.h                        |   1 +
 12 files changed, 991 insertions(+), 1 deletion(-)
---
base-commit: a08b2b34239e63bd839078de98911d3653cdab83
change-id: 20250224-hdp-upstream-622e5da14a9f

Best regards,
-- 
Clément Le Goffic [off-list ref]