mmc: sdhci: change sdhci-pltfm into a module

There are a couple of problems left from the sdhci pltfm and OF
consolidation changes.

* When building more than one sdhci-pltfm based drivers in the same
  image, linker will give multiple definition error on the sdhci-pltfm
  helper functions.  For example right now, building sdhci-of-esdhc
  and sdhci-of-hlwd together is a valid combination from Kconfig view.

* With the current build method, there is error with building the
  drivers as module, but module installation fails with modprobe.

The patch fixes above problems by changing sdhci-pltfm into a module.
To avoid EXPORT_SYMBOL on so many big endian IO accessors, it moves
these accessors into sdhci-pltfm.h as the 'static inline' functions.
As a result, sdhci.h needs to be included in sdhci-pltfm.h, and in
turn can be removed from individual drivers which already include
sdhci-pltfm.h.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>

1 files changed, 29 insertions, 8 deletions

diff --git a/drivers/mmc/host/Kconfig b/drivers/mmc/host/Kconfig
index ee4ac77..74e77c9 100644
--- a/drivers/mmc/host/Kconfig
+++ b/drivers/mmc/host/Kconfig
@@ -81,19 +81,32 @@ config MMC_RICOH_MMC
 
 	  If unsure, say Y.
 
-config MMC_SDHCI_OF_ESDHC
-	bool "SDHCI OF support for the Freescale eSDHC controller"
+config MMC_SDHCI_PLTFM
+	tristate "SDHCI platform and OF driver helper"
 	depends on MMC_SDHCI
+	help
+	  This selects the common helper functions support for Secure Digital
+	  Host Controller Interface based platform and OF drivers.
+
+	  If you have a controller with this interface, say Y or M here.
+
+	  If unsure, say N.
+
+config MMC_SDHCI_OF_ESDHC
+	tristate "SDHCI OF support for the Freescale eSDHC controller"
+	depends on MMC_SDHCI_PLTFM
 	depends on PPC_OF
 	select MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER
 	help
 	  This selects the Freescale eSDHC controller support.
 
+	  If you have a controller with this interface, say Y or M here.
+
 	  If unsure, say N.
 
 config MMC_SDHCI_OF_HLWD
-	bool "SDHCI OF support for the Nintendo Wii SDHCI controllers"
-	depends on MMC_SDHCI
+	tristate "SDHCI OF support for the Nintendo Wii SDHCI controllers"
+	depends on MMC_SDHCI_PLTFM
 	depends on PPC_OF
 	select MMC_SDHCI_BIG_ENDIAN_32BIT_BYTE_SWAPPER
 	help
@@ -101,43 +114,51 @@ config MMC_SDHCI_OF_HLWD
 	  found in the "Hollywood" chipset of the Nintendo Wii video game
 	  console.
 
+	  If you have a controller with this interface, say Y or M here.
+
 	  If unsure, say N.
 
 config MMC_SDHCI_CNS3XXX
 	tristate "SDHCI support on the Cavium Networks CNS3xxx SoC"
 	depends on ARCH_CNS3XXX
-	depends on MMC_SDHCI
+	depends on MMC_SDHCI_PLTFM
 	help
 	  This selects the SDHCI support for CNS3xxx System-on-Chip devices.
 
+	  If you have a controller with this interface, say Y or M here.
+
 	  If unsure, say N.
 
 config MMC_SDHCI_ESDHC_IMX
 	tristate "SDHCI platform support for the Freescale eSDHC i.MX controller"
 	depends on ARCH_MX25 || ARCH_MX35 || ARCH_MX5
-	depends on MMC_SDHCI
+	depends on MMC_SDHCI_PLTFM
 	select MMC_SDHCI_IO_ACCESSORS
 	help
 	  This selects the Freescale eSDHC controller support on the platform
 	  bus, found on platforms like mx35/51.
 
+	  If you have a controller with this interface, say Y or M here.
+
 	  If unsure, say N.
 
 config MMC_SDHCI_DOVE
 	tristate "SDHCI support on Marvell's Dove SoC"
 	depends on ARCH_DOVE
-	depends on MMC_SDHCI
+	depends on MMC_SDHCI_PLTFM
 	select MMC_SDHCI_IO_ACCESSORS
 	help
 	  This selects the Secure Digital Host Controller Interface in
 	  Marvell's Dove SoC.
 
+	  If you have a controller with this interface, say Y or M here.
+
 	  If unsure, say N.
 
 config MMC_SDHCI_TEGRA
 	tristate "SDHCI platform support for the Tegra SD/MMC Controller"
 	depends on ARCH_TEGRA
-	depends on MMC_SDHCI
+	depends on MMC_SDHCI_PLTFM
 	select MMC_SDHCI_IO_ACCESSORS
 	help
 	  This selects the Tegra SD/MMC controller. If you have a Tegra