Add build files

.clang-format

@@ -3,3 +3,4 @@ IndentWidth: 4
 UseTab: Never
 ColumnLimit: 100
 AllowShortFunctionsOnASingleLine: Inline
+SortIncludes: false

.gitignore

@@ -30,3 +30,4 @@ videos/**
 .piolibdeps
 lib/
 .vscode/
+bin

brick/Makefile

@@ -0,0 +1,12 @@
+all: mod uf2
+
+mod:
+	$(MAKE) -C .. MOD=d_usbdev M=`pwd`/kernel ARCH=arm CROSS_COMPILE=arm-none-linux-gnueabi-
+	@mkdir -p bin
+	cp kernel/*.ko bin/
+
+uf2:
+	$(MAKE) -C uf2daemon
+	@mkdir -p bin
+	cp uf2daemon/server bin/uf2daemon
+

brick/README.md

@@ -0,0 +1,34 @@
+# Support code to run on EV3 brick
+
+## Kernel module
+
+Kernel module is based on LEGO's `d_usbdev` module, with the addition of slightly modified `g_mass_storage`
+module from the Linux kernel. The module and supporting sources are licensed under GPLv2 (since
+they are derived from GPLv2 code).
+
+### Modifications
+
+* the `d_usbdev` uses the composite framework to register an additional mass storage function in addtion
+  to the pre-existing custom USB HID function
+* the `g_mass_storage` module has the following changes:
+  * a bug fixed, where page-misaligned writes would hang
+  * additional `/sys/.../lun0/active` entry is added, which allows for signaling drive eject to the host
+
+### Kernel modifications
+
+The kernel itself has modified FIFO queue sizes. The LEGO kernel uses `1024` for `ep1in` and `ep1out`,
+and then `64` for `ep2` and `ep3`. Note that this is non-standard modification done with a kernel patch,
+that I didn't manage to find.  The MSD requires `512` for `ep2` and `ep3`. I have binary edited the kernel
+to do so.
+
+Note that there's 4k of FIFO memory in the hardware. If you set the queue sizes with a sum of more than
+4k, the kernel will hang, and you will not know why.
+
+## UF2 Daemon
+
+The [UF2](https://github.com/Microsoft/uf2) daemon is based on 
+[UF2 ATSAMD21](https://github.com/Microsoft/uf2-samd21) bootloader code. It exposes a virtual
+FAT16 file system over Linux Network Block Device interface (`/dev/nbd0` to be precise).
+This device is then exposed via the `g_mass_storage` module to the host computer.
+
+The Daemon is licensed under MIT.

brick/ins

@@ -0,0 +1,22 @@
+#!/bin/sh
+set -ex
+cd /mnt/ramdisk/prjs/ko
+insmod ./nbd.ko
+sleep 1
+./nbd-serv &
+sleep 1
+insmod ./d_usbdev.ko file=/dev/nbd0 HostStr=EV3 SerialStr=0016535543af
+L=/sys/devices/platform/musb_hdrc/gadget/lun0
+echo $L
+echo -n "ent: "
+read LINE
+#echo > $L/file
+echo 3 > $L/reset
+killall nbd-serv
+sleep 1
+./nbd-serv &
+sleep 1
+#echo /dev/nbd0 > $L/file
+#sleep 1
+echo 4 > $L/reset
+

brick/mk

@@ -0,0 +1,7 @@
+#!/bin/sh
+set -xe
+scp -qr * vm:linux/pxt/ 
+ssh vm "cd linux/pxt; make $1"
+mkdir -p bin
+scp vm:linux/pxt/bin/* bin/
+

brick/send

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+./mk
+ev3duder up bin/d_usbdev.ko ../prjs/ko/d_usbdev.ko
+ev3duder up bin/nbd.ko ../prjs/ko/nbd.ko
+ev3duder up bin/nbd-serv ../prjs/ko/nbd-serv
+ev3duder up ins ../prjs/ko/ins
+