From 3c232895b8352418b3b98469a6af6503d2b0c416 Mon Sep 17 00:00:00 2001 From: Patryk Duda Date: Tue, 18 May 2021 16:07:58 +0200 Subject: [PATCH] platform/chrome: cros_ec_proto: Send command again when timeout occurs commit 3abc16af57c9939724df92fcbda296b25cc95168 upstream. Sometimes kernel is trying to probe Fingerprint MCU (FPMCU) when it hasn't initialized SPI yet. This can happen because FPMCU is restarted during system boot and kernel can send message in short window eg. between sysjump to RW and SPI initialization. Cc: # 4.4+ Signed-off-by: Patryk Duda Link: https://lore.kernel.org/r/20210518140758.29318-1-pdk@semihalf.com Signed-off-by: Benson Leung Signed-off-by: Greg Kroah-Hartman --- drivers/platform/chrome/cros_ec_proto.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c index f659f96bda12..9b575e9dd71c 100644 --- a/drivers/platform/chrome/cros_ec_proto.c +++ b/drivers/platform/chrome/cros_ec_proto.c @@ -213,6 +213,15 @@ static int cros_ec_host_command_proto_query(struct cros_ec_device *ec_dev, msg->insize = sizeof(struct ec_response_get_protocol_info); ret = send_command(ec_dev, msg); + /* + * Send command once again when timeout occurred. + * Fingerprint MCU (FPMCU) is restarted during system boot which + * introduces small window in which FPMCU won't respond for any + * messages sent by kernel. There is no need to wait before next + * attempt because we waited at least EC_MSG_DEADLINE_MS. + */ + if (ret == -ETIMEDOUT) + ret = send_command(ec_dev, msg); if (ret < 0) { dev_dbg(ec_dev->dev,