make_mmc_spi.sh

sudo apt-get update
sudo apt-get install linux-headers-`uname -r`
cd
mkdir linux
cd linux/
git init
git config core.sparsecheckout true
git remote add origin https://github.com/beagleboard/linux
echo drivers/mmc/host > .git/info/sparse-checkout                                                   
git fetch origin/4.9 --depth 1
git checkout 4.9
cd drivers/mmc/host
CONFIG_MMC_SPI=m make -C /lib/modules/`uname -r`/build M=$PWD
sudo make -C /lib/modules/`uname -r`/build M=$PWD INSTALL_MOD_DIR=kernel/drivers/mmc/host modules_install
sudo /opt/scripts/tools/developers/update_initrd.sh
cd /opt/source/bb.org-overlays
echo <<EOF > src/arm/PB-SPI1-MICROSD-CLICK.dts
/*
 * Copyright (C) 2018 Texas Instruments, Jason Kridner <jdk@ti.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * https://www.mikroe.com/microsd-click
 * https://download.mikroe.com/documents/add-on-boards/click/microsd/microsd-click-schematic.pdf
 */

/dts-v1/;
/plugin/;

#include <dt-bindings/gpio/gpio.h>
#include <dt-bindings/pinctrl/am33xx.h>
#include <dt-bindings/interrupt-controller/irq.h>

/ {
	/*
	 * Free up the pins used by the cape from the pinmux helpers.
	 */
	fragment@0 {
		target = <&ocp>;
		__overlay__ {
			P1_36_pinmux { status = "disabled"; };	/* CD - gpio3_14*/
			P2_25_pinmux { status = "disabled"; };	/* MOSI - gpio1_9 */
			P2_27_pinmux { status = "disabled"; };	/* MISO - gpio1_8 */
			P2_29_pinmux { status = "disabled"; };	/* CLK - gpio0_7 */
			P2_31_pinmux { status = "disabled"; };	/* CS - gpio0_19 */
			cape-universal { status = "disabled"; };
			cape-universal@1 { status = "disabled"; };
		};
	};

	fragment@1 {
		target = <&spi1>;
		__overlay__ {
			#address-cells = <1>;
			#size-cells = <0>;
			status = "okay";

			channel@0 {
				status = "disabled";
			};
			channel@1 {
				status = "disabled";
			};

			mikroe_microsd: mikroe_microsd@0{
				compatible = "mmc-spi-slot";
				pinctrl-names = "default";
				pinctrl-0 = <
					&P2_31_spi_cs_pin
					&P2_29_spi_sclk_pin
					&P2_27_spi_pin
					&P2_25_spi_pin
					&P1_36_gpio_pin
				>;
				
				reg = <1>;
				gpios = <&gpio3 14 0>;
				voltage-ranges = <3300 3300>;
				spi-max-frequency = <50000000>;
				interrupts = <&gpio3>;
				interrupt-parent = <14 IRQ_TYPE_EDGE_BOTH>;				
			};
		};
	};
};

make
sudo make install
sudo perl -i -pe 's/^#(.*)<file0>/$1PB-SPI1-MICROSD-CLICK/;' /boot/uEnv.txt