sunxi: Add SUN6I_P2WI kconfig entry

Add simple and meaningful kconfig option for p2wi.c
instead of using MACH type on Makefile.

Signed-off-by: Jagan Teki <jagan@amarulasolutions.com>
Acked-by: Maxime Ripard <maxime.ripard@bootlin.com>
diff --git a/arch/arm/mach-sunxi/Kconfig b/arch/arm/mach-sunxi/Kconfig
index dd1cf01..8157381 100644
--- a/arch/arm/mach-sunxi/Kconfig
+++ b/arch/arm/mach-sunxi/Kconfig
@@ -6,6 +6,17 @@
 config IDENT_STRING
 	default " Allwinner Technology"
 
+config SUN6I_P2WI
+	bool "Allwinner sun6i internal P2WI controller"
+	help
+	  If you say yes to this option, support will be included for the
+	  P2WI (Push/Pull 2 Wire Interface) controller embedded in some sunxi
+	  SOCs.
+	  The P2WI looks like an SMBus controller (which supports only byte
+	  accesses), except that it only supports one slave device.
+	  This interface is used to connect to specific PMIC devices (like the
+	  AXP221).
+
 config SUN6I_PRCM
 	bool
 	help
@@ -94,6 +105,7 @@
 	select CPU_V7_HAS_NONSEC
 	select CPU_V7_HAS_VIRT
 	select ARCH_SUPPORT_PSCI
+	select SUN6I_P2WI
 	select SUN6I_PRCM
 	select SUNXI_GEN_SUN6I
 	select SUPPORT_SPL
diff --git a/arch/arm/mach-sunxi/Makefile b/arch/arm/mach-sunxi/Makefile
index 9713fd5..1284b0e 100644
--- a/arch/arm/mach-sunxi/Makefile
+++ b/arch/arm/mach-sunxi/Makefile
@@ -16,10 +16,10 @@
 ifndef CONFIG_MACH_SUN9I
 obj-y	+= usb_phy.o
 endif
+obj-$(CONFIG_SUN6I_P2WI)	+= p2wi.o
 obj-$(CONFIG_SUN6I_PRCM)	+= prcm.o
 obj-$(CONFIG_MACH_SUN8I)	+= prcm.o
 obj-$(CONFIG_MACH_SUN9I)	+= prcm.o
-obj-$(CONFIG_MACH_SUN6I)	+= p2wi.o
 obj-$(CONFIG_MACH_SUN8I)	+= rsb.o
 obj-$(CONFIG_MACH_SUN9I)	+= rsb.o
 obj-$(CONFIG_MACH_SUN4I)	+= clock_sun4i.o