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authorPatryk Duda <pdk@semihalf.com>2021-05-18 16:07:58 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2021-09-22 11:41:26 +0200
commit7d949dc36038d3c29f34007abb7dfea8bcb9e397 (patch)
tree683fc0e2df25bae4252ccce65df08003e1ac06f8 /drivers
parentcd6ede691876e483d87b91108cd06c98ca894370 (diff)
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: <stable@vger.kernel.org> # 4.4+ Signed-off-by: Patryk Duda <pdk@semihalf.com> Link: https://lore.kernel.org/r/20210518140758.29318-1-pdk@semihalf.com Signed-off-by: Benson Leung <bleung@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/platform/chrome/cros_ec_proto.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index d20190c8f0c0..db2cd5994c2d 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -182,6 +182,15 @@ 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,