edac: add edac_device_alloc_index()

Add edac_device_alloc_index(), because for MAPLE platform there may
exist several EDAC driver modules that could make use of
edac_device_ctl_info structure at the same time. The index allocation
for these structures should be taken care of by EDAC core.

[akpm@linux-foundation.org: cleanups]
Signed-off-by: Harry Ciao <qingtao.cao@windriver.com>
Cc: Doug Thompson <norsk5@yahoo.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/edac/amd8111_edac.c b/drivers/edac/amd8111_edac.c
index 2cb58ef..35b78d0 100644
--- a/drivers/edac/amd8111_edac.c
+++ b/drivers/edac/amd8111_edac.c
@@ -37,7 +37,6 @@
 #define AMD8111_EDAC_MOD_STR	"amd8111_edac"
 
 #define PCI_DEVICE_ID_AMD_8111_PCI	0x7460
-static int edac_dev_idx;
 
 enum amd8111_edac_devs {
 	LPC_BRIDGE = 0,
@@ -377,7 +376,7 @@
 	 * edac_device_ctl_info, but make use of existing
 	 * one instead.
 	*/
-	dev_info->edac_idx = edac_dev_idx++;
+	dev_info->edac_idx = edac_device_alloc_index();
 	dev_info->edac_dev =
 		edac_device_alloc_ctl_info(0, dev_info->ctl_name, 1,
 					   NULL, 0, 0,