Re: [PATCH v6] platform/chrome: cros_ec: Query EC protocol version if EC transitions between RO/RW

From: Enric Balletbo i Serra
Date: Tue Feb 11 2020 - 04:42:23 EST



On 3/2/20 23:53, Yicheng Li wrote:
> RO and RW of EC may have different EC protocol version. If EC transitions
> between RO and RW, but AP does not reboot (this is true for fingerprint
> microcontroller / cros_fp, but not true for main ec / cros_ec), the AP
> still uses the protocol version queried before transition, which can
> cause problems. In the case of fingerprint microcontroller, this causes
> AP to send the wrong version of EC_CMD_GET_NEXT_EVENT to RO in the
> interrupt handler, which in turn prevents RO to clear the interrupt
> line to AP, in an infinite loop.
>
> Once an EC_HOST_EVENT_INTERFACE_READY is received, we know that there
> might have been a transition between RO and RW, so re-query the protocol.
>
> Signed-off-by: Yicheng Li <yichengli@xxxxxxxxxxxx>
> ---

Queued for 5.7 with all the collected tags, thanks.