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linux Undefined references to OMAP2420 functions

Weaker generic dependencies on ARCH_OMAP2 were allowing, for instance, to make use of omap24xx_* functions without enabling support for OMAP2420.

Bug fixed by commit 6515e48932c

Type	UndefinedSymbol
Config	"MACH_OMAP_H4 && !ARCH_OMAP2420" (2nd degree)
Fix-in	model
Location	arch/arm/

#if defined(CONFIG_ARCH_OMAP2420)
void omap2_set_globals_242x(void)
{
  return;
}
#endif

#ifdef CONFIG_MACH_OMAP_H4
static void omap_h4_map_io(void)
{
  omap2_set_globals_242x(); // ERROR
}
#endif

int main(int argc, char** argv)
{
#ifdef CONFIG_MACH_OMAP_H4
  omap_h4_map_io();
#endif
}

diff --git a/simple/6515e48.c b/simple/6515e48.c
--- a/simple/6515e48.c
+++ b/simple/6515e48.c
@@ -1,3 +1,7 @@
+#ifdef CONFIG_MACH_OMAP_H4
+#define CONFIG_ARCH_OMAP2420
+#endif
+
 #if defined(CONFIG_ARCH_OMAP2420)
 void omap2_set_globals_242x(void)
 {