mtd: nand: Force omap_elm to be built as a module if omap2_nand is a module

This commit adds a hidden option to build the omap_elm as a module, if
omap2_nand is a module (and similarly in the built-in case).

This fixes the following build error when omap2_nand is chosen built-in,
and omap_elm is chosen as a module:

drivers/built-in.o: In function `omap_nand_probe':
drivers/mtd/nand/omap2.c:2010: undefined reference to `elm_config'
drivers/mtd/nand/omap2.c:1980: undefined reference to `elm_config'
drivers/mtd/nand/omap2.c:1927: undefined reference to `elm_config'
drivers/built-in.o: In function `omap_elm_correct_data':
drivers/mtd/nand/omap2.c:1444: undefined reference to `elm_decode_bch_error_page'

Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Ezequiel Garcia <ezequiel@vanguardiasur.com.ar>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>

2 files changed, 5 insertions, 2 deletions

diff --git a/drivers/mtd/nand/Kconfig b/drivers/mtd/nand/Kconfig
index f1cf503517fd..1cb4b1ba59ec 100644
--- a/drivers/mtd/nand/Kconfig
+++ b/drivers/mtd/nand/Kconfig
@@ -96,7 +96,7 @@ config MTD_NAND_OMAP2
 
 config MTD_NAND_OMAP_BCH
         depends on MTD_NAND_OMAP2
-        tristate "Support hardware based BCH error correction"
+        bool "Support hardware based BCH error correction"
         default n
         select BCH
         help
@@ -106,6 +106,9 @@ config MTD_NAND_OMAP_BCH
           legacy OMAP families like OMAP2xxx, OMAP3xxx do not have ELM engine
           so they should not enable this config symbol.
 
+config MTD_NAND_OMAP_BCH_BUILD
+        def_tristate MTD_NAND_OMAP2 && MTD_NAND_OMAP_BCH
+
 config MTD_NAND_IDS
         tristate
 
diff --git a/drivers/mtd/nand/Makefile b/drivers/mtd/nand/Makefile
index b3237b742eb5..9c847e469ca7 100644
--- a/drivers/mtd/nand/Makefile
+++ b/drivers/mtd/nand/Makefile
@@ -27,7 +27,7 @@ obj-$(CONFIG_MTD_NAND_NDFC)		+= ndfc.o
 obj-$(CONFIG_MTD_NAND_ATMEL)            += atmel_nand.o
 obj-$(CONFIG_MTD_NAND_GPIO)             += gpio.o
 obj-$(CONFIG_MTD_NAND_OMAP2)            += omap2.o
-obj-$(CONFIG_MTD_NAND_OMAP_BCH)         += omap_elm.o
+obj-$(CONFIG_MTD_NAND_OMAP_BCH_BUILD)   += omap_elm.o
 obj-$(CONFIG_MTD_NAND_CM_X270)          += cmx270_nand.o
 obj-$(CONFIG_MTD_NAND_PXA3xx)           += pxa3xx_nand.o
 obj-$(CONFIG_MTD_NAND_TMIO)             += tmio_nand.o