formfactor: detect USB HID keyboard and touch screen

The new machconfig probes USB keyboard and touch screen, and
then sets HAVE_* variables according to detection.

Detectable devices:
USB HID keyboards (Generic Desktop)
USB HID touch screens (Digitizer)

Note:
The intention is to have a way to provide initial formfactor
settings in a boot procedure. That means supported keyboard
and touch screen must be connected before machconfig runs.
Any new connection or disconnection won't be detected until
machconfig is executed again.

Limitation:
There could be some USB HID devices presents more than one
usage in a single descriptor. We will add support once such
device emerges.

Some platforms may have _virtual_ devices provided by BIOS.
It will cause false detection when they are presented as
types we supported. We can add black list logic when it
becomes a big concern.

Fixes [YOCTO #9205]

Signed-off-by: Jianxun Zhang <jianxun.zhang@linux.intel.com>
Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>

1 files changed, 1 insertions, 0 deletions

diff --git a/common/recipes-bsp/formfactor/formfactor_0.0.bbappend b/common/recipes-bsp/formfactor/formfactor_0.0.bbappend
new file mode 100644
index 00000000..72d991c7
--- /dev/null
+++ b/common/recipes-bsp/formfactor/formfactor_0.0.bbappend
@@ -0,0 +1 @@
+FILESEXTRAPATHS_prepend := "${THISDIR}/${PN}:"