X-Powers AXP288 is a customized PMIC for Intel Baytrail-CR platforms. Similar
to AXP202/209, AXP288 comes with USB charger, more LDO and BUCK channels, and
AD converters. It also provides extended status and interrupt reporting
capabilities than the devices currently supported in axp20x.c.

In addition to feature extension, this patch also adds ACPI binding for
enumeration.

This consolidated driver should support more X-Powers' PMICs in both device
tree and ACPI enumerated platforms.
Signed-off-by: NJacob Pan <jacob.jun.pan@linux.intel.com>
Reviewed-by: NMaxime Ripard <maxime.ripard@free-electrons.com>
Reviewed-by: NJonathan Cameron <jic23@kernel.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>

This patch introduces the preliminary support for PMICs X-Powers AXP202
and AXP209. The AXP209 and AXP202 are the PMUs (Power Management Unit)
used by A10, A13 and A20 SoCs and developed by X-Powers, a sister company
of Allwinner.

The core enables support for two subsystems:
- PEK (Power Enable Key)
- Regulators
Signed-off-by: NCarlo Caione <carlo@caione.org>
Signed-off-by: NLee Jones <lee.jones@linaro.org>