Cr50: I2CS TPM: Prevent sleep when I2CS is activestabilize-8838.B

Similar to the TPM SPI interface, added code to disable sleep an I2CS
interrupt is received. Enabling sleep follwoing a 1 second delay when
the TPM fifo register has been read by the host. The I2CS TPM layer
doesn't know when a command has finished, but the one second delay is
more than enough delay since sleep will be disabled again when the
next I2CS interrupt is received.

BRANCH=none
BUG=chrome-os-partner:40397
TEST=manual
Tested without these changes first. Shortened sleep delay to 30
seconds, and disconnected suzyq. Waited 30 seconds then issued the
command on the AP console:

tpmc read 0x1007 0xa
[   59.796813] tpm tpm0: tpm_transmit: tpm_send: error -16
ERROR: write failure to TPM device: Device or resource busy

In addition, using logic analyzer verifed that there was activity on
SDA/SCL but no response from Cr50. With this CL in place, ran the
test and got the following:

tpmc read 0x1007 0xa
2 0 1 0 1 0 0 0 0 4f

With the logic analyzer I was able to confirm that there was no
activity from the host on the I2CS bus until the command was issued.

Change-Id: If07573ae8f72b983bca57979d53c22660b91b95e
Signed-off-by: Scott <scollyer@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/387910
Commit-Ready: Scott Collyer <scollyer@chromium.org>
Tested-by: Scott Collyer <scollyer@chromium.org>
Reviewed-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Mary Ruthven <mruthven@chromium.org>

0 files changed, 0 insertions, 0 deletions