[RFC PATCH v2 00/13] arm/tegra: Initialize GPIO & pinmux from DT

Linus Walleij linus.walleij at linaro.org
Tue Aug 23 08:51:17 EDT 2011


On Tue, Aug 16, 2011 at 7:12 PM, Stephen Warren <swarren at nvidia.com> wrote:

> One issue here: There isn't always a single gpio/pinmux parent; as a
> concrete example, the ALSA/ASoC driver for Tegra+WM8903 uses GPIOs both
> from Tegra itself, and from the WM8903 audio codec.

The Ux500 have pinmuxing on the DB8500 and AB8500 - the latter
is a PMIC (&misc) connected to the DB8500 via I2C.

In the pincontrol subsystem I'm brewing, each of these will have
their own pin controller instance and their own struct gpio_chip as
well, so:

DB8500: pinctrl.0, gpio.0
AB8500: pinctrl.1, gpio.1

Each GPIO chip may have it's respective pin controller as parent
I guess, or they may simply be the same struct device * whatdoIknow.

I know this is vaporware, but does this reasoning hold also to
the Tegra+WM8903 combo?

Linus Walleij



More information about the linux-arm-kernel mailing list