BCM270X_DT: Document SMI overlay

Author: Phil Elwell

arch/arm/boot/dts/overlays/Makefile

@@ -13,9 +13,6 @@ ifeq ($(CONFIG_ARCH_BCM2835),y)
 endif
 
 dtb-$(RPI_DT_OVERLAYS) += ads7846-overlay.dtb
-dtb-$(RPI_DT_OVERLAYS) += smi-overlay.dtb
-dtb-$(RPI_DT_OVERLAYS) += smi-dev-overlay.dtb
-dtb-$(RPI_DT_OVERLAYS) += smi-nand-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += bmp085_i2c-sensor-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += dht11-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += enc28j60-overlay.dtb
@@ -48,6 +45,9 @@ dtb-$(RPI_DT_OVERLAYS) += rpi-proto-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += rpi-sense-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += sdhost-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += sdio-overlay.dtb
+dtb-$(RPI_DT_OVERLAYS) += smi-dev-overlay.dtb
+dtb-$(RPI_DT_OVERLAYS) += smi-nand-overlay.dtb
+dtb-$(RPI_DT_OVERLAYS) += smi-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += spi-bcm2708-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += spi-bcm2835-overlay.dtb
 dtb-$(RPI_DT_OVERLAYS) += spi-dma-overlay.dtb

arch/arm/boot/dts/overlays/README

@@ -530,6 +530,24 @@ Params: overclock_50             Clock (in MHz) to use when the MMC framework
         debug                    Enable debug output (default off)
 
 
+Name:   smi
+Info:   Enables the Secondary Memory Interface peripheral. Uses GPIOs 2-25!
+Load:   dtoverlay=smi
+Params: <None>
+
+
+Name:   smi-dev
+Info:   Enables the userspace interface for the SMI driver
+Load:   dtoverlay=smi-dev
+Params: <None>
+
+
+Name:   smi-nand
+Info:   Enables access to NAND flash via the SMI interface
+Load:   dtoverlay=smi-nand
+Params: <None>
+
+
 Name:   spi-bcm2708
 Info:   Selects the bcm2708-spi SPI driver
 Load:   dtoverlay=spi-bcm2708