OMAP2+: PRM: add register access functions for VC/VP

On OMAP3+, the voltage controller (VC) and voltage processor (VP) are
inside the PRM.  Add some PRM helper functions for register access to
these module registers.

Thanks to Nishanth Menon for finding/fixing a sparse problem.

Cc: Nishanth Menon <nm@ti.com>
Signed-off-by: Kevin Hilman <khilman@ti.com>
diff --git a/arch/arm/mach-omap2/prm44xx.c b/arch/arm/mach-omap2/prm44xx.c
index 390e32c..495a31a 100644
--- a/arch/arm/mach-omap2/prm44xx.c
+++ b/arch/arm/mach-omap2/prm44xx.c
@@ -24,6 +24,8 @@
 #include "vp.h"
 #include "prm44xx.h"
 #include "prm-regbits-44xx.h"
+#include "prcm44xx.h"
+#include "prminst44xx.h"
 
 /* PRM low-level functions */
 
@@ -99,3 +101,23 @@
 				     OMAP4430_PRM_OCP_SOCKET_INST,
 				     vp->irqstatus_mpu);
 };
+
+u32 omap4_prm_vcvp_read(u8 offset)
+{
+	return omap4_prminst_read_inst_reg(OMAP4430_PRM_PARTITION,
+					   OMAP4430_PRM_DEVICE_INST, offset);
+}
+
+void omap4_prm_vcvp_write(u32 val, u8 offset)
+{
+	omap4_prminst_write_inst_reg(val, OMAP4430_PRM_PARTITION,
+				     OMAP4430_PRM_DEVICE_INST, offset);
+}
+
+u32 omap4_prm_vcvp_rmw(u32 mask, u32 bits, u8 offset)
+{
+	return omap4_prminst_rmw_inst_reg_bits(mask, bits,
+					       OMAP4430_PRM_PARTITION,
+					       OMAP4430_PRM_DEVICE_INST,
+					       offset);
+}