Cr50: Add extra/sps_errs/ test program

This adds another test program to use with the EC connected to
the build host via an FTDI USB-to-SPI adapater, This program
sends an EC_CMD_HELLO host command to the EC. Options exist to
display the bytes transferred over the SPI interface, and to
truncate the message before its complete, to see how the EC reacts.

BUG=chrome-os-partner:40969
BRANCH=none
TEST=make buildall

To try out the new test program:

  cd extra/sps_errs
  make
  ./prog
  ./prog -v
  ./prog -v -c 22

Change-Id: I1d370ecdbae047d9504bc6e5f73949d4e3aed9d9
Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/284865
Reviewed-by: Vadim Bendebury <vbendeb@google.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/extra/sps_errs/README b/extra/sps_errs/README
new file mode 100644
index 0000000000..d1fbb6b43f
--- /dev/null
+++ b/extra/sps_errs/README
@@ -0,0 +1,28 @@
+SETUP:
+
+  Attach an EC to the build host using an FTDI USB-to-SPI adapter.
+
+BUILD:
+
+  make
+  ./prog
+
+
+USAGE:
+
+  Usage: ./prog [-v] [-c BYTES]
+
+  This sends a EC_CMD_HELLO host command. The -c option can
+  be used to truncate the exchange early, to see how the EC
+  deals with the interruption.
+
+NOTE:
+
+  Ubuntu Trusty uses an ancient version of libftdi.
+
+  If building outside of the Chromium chroot, you'll probably want to grab the
+  latest libftdi1-1.2.tar.bz2 from
+
+    http://www.intra2net.com/en/developer/libftdi/
+
+  and install it into /usr instead.