[PATCH v3 0/2] spi: ma35d1-qspi: Enable GPIO chip-select support

[Chi-Wen Weng <cwweng.linux@gmail.com>]

From: Chi-Wen Weng <cwweng@nuvoton.com>

The generic SPI controller binding allows GPIO-based chip selects, but
the MA35D1 QSPI driver currently supports only the controller's two
native chip selects.

This series enables GPIO descriptor-based chip-select handling in the
driver and updates the binding so that num-cs can describe the total
number of native and GPIO chip selects.

Patch 1 removes the native hardware limit from the binding's num-cs
property.

Patch 2 enables GPIO chip selects in the driver while retaining the
hardware limit of two native chip selects.

Changes in v3:

* Split the binding and driver changes into a two-patch series.
* Allow num-cs to exceed the two native chip selects when GPIO chip
  selects are present.
* Remove the driver's upper limit of two from num-cs.
* Rename the native chip-select limit for clarity.
* Reject out-of-range native chip-select indices in the setup callback.
* Retain active-high support for GPIO chip selects only.

Changes in v2:

* Enable GPIO descriptor-based chip-select handling in the driver
  instead of disallowing cs-gpios in the binding.
* Set the maximum number of native chip selects to two.
* Reject active-high polarity only for native chip selects.

Chi-Wen Weng (2):
  dt-bindings: spi: nuvoton,ma35d1-qspi: Allow additional GPIO chip
    selects
  spi: ma35d1-qspi: Enable GPIO chip selects

 .../bindings/spi/nuvoton,ma35d1-qspi.yaml     |  1 -
 drivers/spi/spi-ma35d1-qspi.c                 | 32 ++++++++++++++++---
 2 files changed, 28 insertions(+), 5 deletions(-)

-- 
2.25.1