tree 3a9ead2c020d82aa97b5424a4255490cc1fc6dbd
parent 1c1806d8df4bb5976eed71a2e2bf156c36ccdce2
author Justin TerAvest <teravest@chromium.org> 1529423633 -0600
committer chrome-bot <chrome-bot@chromium.org> 1529529829 -0700

vpd_get_value: Allow sysfs reads when ro missing

For reference boards, there may be no VPD provisioned at manufacturing
time. This causes vpd_get_value requests to fall back to dump_vpd_log
unnecessarily, which can take over two seconds.

This commit also checks for the presence of an "rw" directory to
determine if vpd data is provided via sysfs on the target system. The OS
populates data in the "rw" section so it can be used even when nothing
was provisioned at manufacturing time.

BUG=b:110024486
TEST=chrome://system loads correctly on yorp with this change
BRANCH=None

Change-Id: Idf239e65bde844a8e9b130fc1ea3d40eaec95af5
Reviewed-on: https://chromium-review.googlesource.com/1106290
Commit-Ready: Justin TerAvest <teravest@chromium.org>
Tested-by: Justin TerAvest <teravest@chromium.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Furquan Shaikh <furquan@chromium.org>