We add 2 hashes that each map to a list of allowed commands
(command list is secret, and provided by Elan).
UPDATE_EXTRA_CMD_TOUCHPAD_DEBUG on the USB interface have the
following format for the parameter:
- param[0]: must be 0xff
- param[1]: offset of the I2C command in data
- param[2]: command length
- param[3-4]: read-back length (MSB first) over I2C, can be 0
- param[5-49]: data, is verified using SHA-256 hash.
The I2C command pointed at by param[1-2] is then sent over
I2C, and the data is read back into a shared buffer of size
param[3-4].
The data can be fetched over USB by a single byte USB update
touchpad debug command (indicating an offset in 64-bytes unit),
fetching data from the shared buffer in blocks of 64 bytes.
BRANCH=none
BUG=b:63993891
TEST=Elan can run debugging commands using their proprietary tool.
Change-Id: Idb19bcb940b7f030c3b3aeaf39d6b725fcb9ef34
Signed-off-by: Nicolas Boichat <drinkcat@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/763576
Reviewed-by: Chun-ta Lin <itspeter@chromium.org>
b9939cf42b