mmc: Add bcm2835 sdhost controller

The BCM2835 family of SoCs has 2 different SD controllers: One based on
the SDHCI spec and a custom, home-grown one.

This patch implements a driver for the latter based on the Linux driver.
This is needed so that we can make use of device trees that assume driver
presence of both SD controllers.

Signed-off-by: Alexander Graf <agraf@suse.de>

MAINTAINERS

@@ -97,6 +97,7 @@ S:	Orphaned (Since 2017-07)
 F:	arch/arm/mach-bcm283x/
 F:	drivers/gpio/bcm2835_gpio.c
 F:	drivers/mmc/bcm2835_sdhci.c
+F:	drivers/mmc/bcm2835_sdhost.c
 F:	drivers/serial/serial_bcm283x_mu.c
 F:	drivers/video/bcm2835.c
 F:	include/dm/platform_data/serial_bcm283x_mu.h

drivers/mmc/Kconfig

@@ -261,6 +261,20 @@ config MMC_UNIPHIER
 	  This selects support for the Matsushita SD/MMC Host Controller on
 	  SocioNext UniPhier and Renesas RCar SoCs.
 
+config MMC_BCM2835
+	bool "BCM2835 family custom SD/MMC Host Controller support"
+	depends on ARCH_BCM283X
+	depends on BLK && DM_MMC
+	depends on OF_CONTROL
+	default y
+	help
+	  This selects support for the custom SD host controller in the BCM2835
+	  family of devices.
+
+	  If you have a BCM2835 platform with SD or MMC devices, say Y here.
+
+	  If unsure, say N.
+
 config MMC_SANDBOX
 	bool "Sandbox MMC support"
 	depends on SANDBOX

drivers/mmc/Makefile

@@ -64,3 +64,4 @@ obj-$(CONFIG_MMC_SDHCI_ZYNQ)		+= zynq_sdhci.o
 
 obj-$(CONFIG_MMC_SUNXI)			+= sunxi_mmc.o
 obj-$(CONFIG_MMC_UNIPHIER)		+= uniphier-sd.o
+obj-$(CONFIG_MMC_BCM2835)		+= bcm2835_sdhost.o