[PATCH v2 0/3] Add initial support for Canaan Kendryte K230 pinctrl

[Ze Huang <18771902331@163.com>]

This patch series introduces support for the pinctrl driver of the Canaan
K230 SoC. The K230 SoC features 64 IO pins, each of which can be configured
for up to five different functions.

The controller manages the entire pin configuration and multiplexing
through a single register, which control features such as schmitt trigger,
drive strength, bias pull-up/down, input/output enable, power source, and
mux mode.

The changes have been tested on CanMV-K230-V1.1 board.

The pin function definition can be found here [1], and most of the DTS data
was converted from the vendor's code [2].

Changes since v1:
- bindings: drop unecessary ref and drop unused labels in dt example
- driver: set remap_config to const
- driver: fix double free of of_node_put
- driver: move probe-related code closer to the probe() function
- driver: drop unlikely MMIO error message and handle correctly minor errors
- driver: replace `for_each_child_of_node` with `for_each_child_of_node_scoped`
- dts: place pinctrl nodes in canmv board level file

Link to v1: https://lore.kernel.org/linux-riscv/20240916063021.311721-1-18771902331@163.com/

Link: https://developer.canaan-creative.com/k230/dev/_downloads/a53655a81951bc8a440ae647be286e75/K230_PINOUT_V1.1_20230321.xlsx [1]
Link: https://github.com/kendryte/k230_sdk/blob/main/src/little/uboot/arch/riscv/dts/k230_canmv.dts [2]

Signed-off-by: Ze Huang <18771902331@163.com>
---
Ze Huang (3):
      dt-bindings: pinctrl: Add support for canaan,k230 SoC
      pinctrl: canaan: Add support for k230 SoC
      riscv: dts: canaan: Add k230's pinctrl node

 .../bindings/pinctrl/canaan,k230-pinctrl.yaml      | 127 ++++
 arch/riscv/boot/dts/canaan/k230-canmv.dts          | 304 ++++++++++
 arch/riscv/boot/dts/canaan/k230-pinctrl.h          |  18 +
 arch/riscv/boot/dts/canaan/k230.dtsi               |   6 +
 drivers/pinctrl/Kconfig                            |  10 +
 drivers/pinctrl/Makefile                           |   1 +
 drivers/pinctrl/pinctrl-k230.c                     | 643 +++++++++++++++++++++
 7 files changed, 1109 insertions(+)
---
base-commit: 0eea987088a22d73d81e968de7347cdc7e594f72
change-id: 20240923-k230-pinctrl-3a323bd75a7e
prerequisite-message-id: <tencent_22BA0425B4DF1CA1713B62E4423C1BFBF809@qq.com>
prerequisite-patch-id: 704efc6e76814e1877748959d7319d558c8386c1
prerequisite-patch-id: c2144cf468c57b856830a61615ba6ba501e8ec58
prerequisite-patch-id: ced4a01ccd8ddab2fd308d543ddf47bd1641518a
prerequisite-patch-id: f8b983b301d0c14f1448b9e4c321262a509e061e
prerequisite-patch-id: 834b65b6a2b037daed5cffc6a41963622568dc9c
prerequisite-patch-id: 2401703b57448c9ea2c3dc7650b4502491a28944

Best regards,
-- 
Ze Huang <18771902331@163.com>