[PATCH 2/4] pinctrl: amlogic: Make driver independent from two-domain configuration

[Kevin Hilman]

Hi Carlo

On Tue, Mar 1, 2016 at 2:04 PM, Carlo Caione <carlo at caione.org> wrote:
> From: Carlo Caione <carlo at endlessm.com>
>
> In the Amlogic Meson8 / Meson8b platforms we have two different buses:
> cbus and aobus, corresponding to 2 different power domains (regular and
> always-on). On each bus a different set of registers is mapped to manage
> muxes, GPIOs and in general to control a clear subset of the pins.
>
> Considering this architecture, having two different pinctrl devices, one
> for each bus / power domain, makes much more sense than just having one
> single device.
>
> Right now we have one single pin controller driver that uses two
> different domains (represented by 'gpio' and 'gpio-ao' sub-nodes in the
> DTS) to manage the set of registers on the two buses. This dual-domain
> configuration is hardcoded into the driver that strictly requires one
> domain for each bus in the same pin controller device.
>
> With this patch we refactor the driver to allow splitting the driver in
> two parts. This change is needed to have a proper description of the HW
> in the device-tree where we want to introduce aobus and cbus.
>
> Signed-off-by: Carlo Caione <carlo at endlessm.com>

kernelci.org detected that the meson8b-odroidc1 started failing boot
test in mainline[1] and I bisected it down to this patch, which is in
mainline in he form of  commit 9dab1868ec0d (pinctrl: amlogic: Make
driver independent from two-domain configuration.)

I confirmed that reverting this patch on top of Linus' master branch
(commit 9256d5a308c9) gets the odroid-c1 booting again.

Kevin

[1] https://kernelci.org/boot/meson8b-odroidc1/job/mainline/kernel/v4.5-1127-g9256d5a308c9/defconfig/multi_v7_defconfig/lab/lab-khilman/?_id=56e9af2359b5146a7a791516