greybus: reserve host cport id 0

Browse source

For ES1 and ES2, we use pad bytes in an operation message header to
encode the CPort ID used for transferring the message.  The pad
bytes should otherwise be zero, and we ensure this as the message
is passed to or from the upper layer.

If host-side CPort ID 0 is used, we have no way of knowing whether
the CPort field has been "packed" into the header.

To allow detection of this, reserve host CPort id 0.  Update
cport_id_valid() to treat 0 as invalid.

(CPort ID 0 is reserved by one of the UniPro standards.  We'll
assume for now that we never use it for Greybus.)

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

...

This commit is contained in:

Alex Elder 2015-06-13 11:02:10 -05:00 • committed by Greg Kroah-Hartman

parent fb690ca96f

commit 88d18a975d

2 changed files with 10 additions and 2 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

10

drivers/staging/greybus/core.c

View file

2

drivers/staging/greybus/greybus.h

View file