USBDEBUG: buffer up to 8 bytes

EHCI debug allows to send message with 8 bytes length, but
we're only sending one byte in each transaction. Buffer up
to 8 bytes to speed up debug output.

Change-Id: I9dbb406833c4966c3afbd610e1b13a8fa3d62f39
Signed-off-by: Sven Schnelle <>
Tested-by: build bot (Jenkins)
Reviewed-by: Nico Huber <>
5 files changed