bus: mvebu-mbus: Provide stub function for mvebu_mbus_get_io_win_info()

This patch provides a stub function for mvebu_mbus_get_io_win_info(),
which will be used for all non-Orion (ARM32 MVEBU) platforms for
compile test coverage.

On such platforms this function will return an error so that drivers
might detect a potential problem.

Signed-off-by: Stefan Roese <sr@denx.de>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Cc: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: Marcin Wojtas <mw@semihalf.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
diff --git a/include/linux/mbus.h b/include/linux/mbus.h
index d610232..2931aa4 100644
--- a/include/linux/mbus.h
+++ b/include/linux/mbus.h
@@ -11,6 +11,8 @@
 #ifndef __LINUX_MBUS_H
 #define __LINUX_MBUS_H
 
+#include <linux/errno.h>
+
 struct resource;
 
 struct mbus_dram_target_info
@@ -55,6 +57,8 @@
 #ifdef CONFIG_PLAT_ORION
 extern const struct mbus_dram_target_info *mv_mbus_dram_info(void);
 extern const struct mbus_dram_target_info *mv_mbus_dram_info_nooverlap(void);
+int mvebu_mbus_get_io_win_info(phys_addr_t phyaddr, u32 *size, u8 *target,
+			       u8 *attr);
 #else
 static inline const struct mbus_dram_target_info *mv_mbus_dram_info(void)
 {
@@ -64,14 +68,24 @@
 {
 	return NULL;
 }
+static inline int mvebu_mbus_get_io_win_info(phys_addr_t phyaddr, u32 *size,
+					     u8 *target, u8 *attr)
+{
+	/*
+	 * On all ARM32 MVEBU platforms with MBus support, this stub
+	 * function will not get called. The real function from the
+	 * MBus driver is called instead. ARM64 MVEBU platforms like
+	 * the Armada 3700 could use the mv_xor device driver which calls
+	 * into this function
+	 */
+	return -EINVAL;
+}
 #endif
 
 int mvebu_mbus_save_cpu_target(u32 __iomem *store_addr);
 void mvebu_mbus_get_pcie_mem_aperture(struct resource *res);
 void mvebu_mbus_get_pcie_io_aperture(struct resource *res);
 int mvebu_mbus_get_dram_win_info(phys_addr_t phyaddr, u8 *target, u8 *attr);
-int mvebu_mbus_get_io_win_info(phys_addr_t phyaddr, u32 *size, u8 *target,
-			       u8 *attr);
 int mvebu_mbus_add_window_remap_by_id(unsigned int target,
 				      unsigned int attribute,
 				      phys_addr_t base, size_t size,