[PATCH v2 0/3] Axiado AX3000 SoC SPI DB controller driver

[Vladimir Moravcevic <vmoravcevic@axiado.com>]

Dear maintainers,

This updated patch series address the review comments from the original submission.
It introduces new SPI controller driver for Axiado AX3000 SoC and its evaluation board.

The SPI controller provides:
- Full-duplex and half-duplex transfer support
- Configurable clock polarity and phase
- Interrupt-driven

Functionality has been verified using the `jedec,spi-nor` interface
to access onboard flash memory. This ensures compatibility with common NOR flash devices
used in boot and storage subsystem.

The driver integrates with the Linux SPI subsystem and follows kernel coding standards.

This initial submission includes:
- Driver implementation under `drivers/spi/`
- Device tree bindings for supported boards
- Kconfig and Makefile integration

Further improvements, including performance tuning and extended hardware feature support,
will be submitted in follow-up patches.

Feedback is welcome.

Signed-off-by: Vladimir Moravcevic <vmoravcevic@axiado.com>
---
Changes in v2:
- remove _clk from clok-names and chage clock style to use <>
- remove set but not use variable
- switch to dev_warn_once
- use devm_spi_alloc_host
- update ax_spi_remove to unregister controller from the subsystem first,
  and then tear down the other resources
- add PM operations 
- update maintainers in dt-bindings
- Flush FIFO while transfer done
- Link to v1: https://lore.kernel.org/r/20250915-axiado-ax3000-soc-spi-db-controller-driver-v1-0-814a1fa2a83e@axiado.com

---
Vladimir Moravcevic (3):
      dt-bindings: spi: axiado,ax3000-spi: Add binding for Axiado SPI DB controller
      spi: axiado: Add driver for Axiado SPI DB controller
      MAINTAINERS: Add entries for the Axiado SPI DB controller

 .../devicetree/bindings/spi/axiado,ax3000-spi.yaml |   63 ++
 MAINTAINERS                                        |   10 +
 drivers/spi/Kconfig                                |   10 +
 drivers/spi/Makefile                               |    1 +
 drivers/spi/spi-axiado.c                           | 1029 ++++++++++++++++++++
 drivers/spi/spi-axiado.h                           |  129 +++
 6 files changed, 1242 insertions(+)
---
base-commit: e6b9dce0aeeb91dfc0974ab87f02454e24566182
change-id: 20250905-axiado-ax3000-soc-spi-db-controller-driver-91a5e27c88ff

Best regards,
-- 
Vladimir Moravcevic <vmoravcevic@axiado.com>