ACPI / PMIC: support PMIC operation region for CrystalCove

The Baytrail-T platform firmware has defined two customized operation
regions for PMIC chip Crystal Cove - one is for power resource handling
and one is for thermal: sensor temperature reporting, trip point setting,
etc. This patch adds support for them on top of the existing Crystal Cove
PMIC driver.

The reason to split code into a separate file intel_pmic.c is that there
are more PMIC drivers with ACPI operation region support coming and we can
re-use those code. The intel_pmic_opregion_data structure is created also
for this purpose: when we need to support a new PMIC's operation region,
we just need to fill those callbacks and the two register mapping tables.

Signed-off-by: Aaron Lu <aaron.lu@intel.com>
Acked-by: Lee Jones <lee.jones@linaro.org> for the MFD part
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index b23fe37..df81645 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -394,4 +394,21 @@
 	  driver adds support for that functionality with corresponding
 	  tracepoint which carries that information to userspace.
 
+menuconfig PMIC_OPREGION
+	bool "PMIC (Power Management Integrated Circuit) operation region support"
+	help
+	  Select this option to enable support for ACPI operation
+	  region of the PMIC chip. The operation region can be used
+	  to control power rails and sensor reading/writing on the
+	  PMIC chip.
+
+if PMIC_OPREGION
+config CRC_PMIC_OPREGION
+	bool "ACPI operation region support for CrystalCove PMIC"
+	depends on INTEL_SOC_PMIC
+	help
+	  This config adds ACPI operation region support for CrystalCove PMIC.
+
+endif
+
 endif	# ACPI