On Fri, Feb 09, 2018 at 05:30:55PM +0200, Andy Shevchenko wrote:

On Fri, Feb 9, 2018 at 2:07 PM, Jonathan Neuschäfer
[off-list ref] wrote:

quoted

The Nintendo Wii's chipset (called "Hollywood") has a GPIO controller
that supports a configurable number of pins (up to 32), interrupts, and
some special mechanisms to share the controller between the system's
security processor (an ARM926) and the PowerPC CPU. Pin multiplexing is
not supported.

This patch adds a basic driver for this GPIO controller. Interrupt
support will come in a later patch.

This patch is based on code developed by Albert Herranz and the GameCube
Linux Team, file arch/powerpc/platforms/embedded6xx/hlwd-gpio.c,
available at https://github.com/DeltaResero/GC-Wii-Linux-Kernels, but
has grown quite dissimilar.

Fine to me, though one comment below.
In any case,

Reviewed-by: Andy Shevchenko <redacted>

Thank you.


[...]

quoted

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index d6a8e851ad13..47606dfe06cc 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig

@@ -229,6 +229,15 @@ config GPIO_GRGPIO
          Select this to support Aeroflex Gaisler GRGPIO cores from the GRLIB
          VHDL IP core library.

+config GPIO_HLWD
+       tristate "Nintendo Wii (Hollywood) GPIO"

quoted

+       depends on OF_GPIO

You may get rid of it if...

[ Even if this driver isn't switched to the unified device property API,
  I think "depends on OF" would be enough here, because it doesn't use
  the code that's guarded by CONFIG_OF_GPIO (gpiolib-of.c), but this
  applies to other drivers (e.g. gpio-aspeed, gpio-bcm-kona) as well, so
  this would ideally be a bigger cleanup patch. ]

quoted

+       res = of_property_read_u32(pdev->dev.of_node, "ngpios", &ngpios);

...if you switch to unified device property API.

I don't think this change is worth making, unless/until the of_property
API is deprecated. I'm rather sure this GPIO controller won't appear in
an ACPI-based system.


Thanks,
Jonathan Neuschäfer