mmc: add a Kconfig option to enable the support for MMC write operations

This allows using CONFIG_IS_ENABLED(MMC_WRITE) to compile out code
needed only if write support is required.
The option is added for u-boot and for SPL
Signed-off-by: NJean-Jacques Hiblot <jjhiblot@ti.com>

cmd/mvebu/bubt.c

@@ -110,7 +110,7 @@ static ulong get_load_addr(void)
 /********************************************************************
  *     eMMC services
  ********************************************************************/
-#ifdef CONFIG_DM_MMC
+#if CONFIG_IS_ENABLED(DM_MMC) && CONFIG_IS_ENABLED(MMC_WRITE)
 static int mmc_burn_image(size_t image_size)
 {
 	struct mmc	*mmc;

common/spl/Kconfig

@@ -301,6 +301,7 @@ config SPL_ENV_SUPPORT
 config SPL_SAVEENV
 	bool "Support save environment"
 	depends on SPL_ENV_SUPPORT
+	select SPL_MMC_WRITE if ENV_IS_IN_MMC
 	help
 	  Enable save environment support in SPL after setenv. By default
 	  the saveenv option is not provided in SPL, but some boards need
@@ -415,6 +416,14 @@ config SPL_MMC_SUPPORT
 	  this option to build the drivers in drivers/mmc as part of an SPL
 	  build.
 
+config SPL_MMC_WRITE
+	bool "MMC/SD/SDIO card support for write operations in SPL"
+	depends on SPL_MMC_SUPPORT
+	default n
+	help
+	  Enable write access to MMC and SD Cards in SPL
+
+
 config SPL_MPC8XXX_INIT_DDR_SUPPORT
 	bool "Support MPC8XXX DDR init"
 	help

drivers/mmc/Kconfig

@@ -10,6 +10,13 @@ config MMC
 	  If you want MMC/SD/SDIO support, you should say Y here and
 	  also to your specific host controller driver.
 
+config MMC_WRITE
+	bool "support for MMC/SD write operations"
+	depends on MMC
+	default y
+	help
+	  Enable write access to MMC and SD Cards
+
 config DM_MMC
 	bool "Enable MMC controllers using Driver Model"
 	depends on DM

drivers/mmc/Makefile

@@ -7,6 +7,7 @@
 
 obj-y += mmc.o
 obj-$(CONFIG_$(SPL_)DM_MMC) += mmc-uclass.o
+obj-$(CONFIG_$(SPL_)MMC_WRITE) += mmc_write.o
 
 ifndef CONFIG_$(SPL_)BLK
 obj-y += mmc_legacy.o
@@ -16,9 +17,6 @@ obj-$(CONFIG_SUPPORT_EMMC_BOOT) += mmc_boot.o
 
 ifdef CONFIG_SPL_BUILD
 obj-$(CONFIG_SPL_MMC_BOOT) += fsl_esdhc_spl.o
-obj-$(CONFIG_SPL_SAVEENV) += mmc_write.o
-else
-obj-y += mmc_write.o
 endif
 
 obj-$(CONFIG_ARM_PL180_MMCI) += arm_pl180_mmci.o

drivers/mmc/mmc-uclass.c

@@ -370,7 +370,7 @@ static int mmc_blk_probe(struct udevice *dev)
 
 static const struct blk_ops mmc_blk_ops = {
 	.read	= mmc_bread,
-#ifndef CONFIG_SPL_BUILD
+#if CONFIG_IS_ENABLED(MMC_WRITE)
 	.write	= mmc_bwrite,
 	.erase	= mmc_berase,
 #endif

drivers/mmc/mmc_private.h

@@ -28,7 +28,7 @@ ulong mmc_bread(struct blk_desc *block_dev, lbaint_t start, lbaint_t blkcnt,
 		void *dst);
 #endif
 
-#if !(defined(CONFIG_SPL_BUILD) && !defined(CONFIG_SPL_SAVEENV))
+#if CONFIG_IS_ENABLED(MMC_WRITE)
 
 #if CONFIG_IS_ENABLED(BLK)
 ulong mmc_bwrite(struct udevice *dev, lbaint_t start, lbaint_t blkcnt,
@@ -40,7 +40,7 @@ ulong mmc_bwrite(struct blk_desc *block_dev, lbaint_t start, lbaint_t blkcnt,
 ulong mmc_berase(struct blk_desc *block_dev, lbaint_t start, lbaint_t blkcnt);
 #endif
 
-#else /* CONFIG_SPL_BUILD and CONFIG_SPL_SAVEENV is not defined */
+#else /* CONFIG_SPL_MMC_WRITE is not defined */
 
 /* declare dummies to reduce code size. */