As with cros_ec_cmd_xfer_status(), etc., it's not enough to simply check
for the return status of send_command() -- that only covers transport or
other similarly-fatal errors. One must also check the ->result field, to
see whether the command really succeeded. If not, we can't use the data
it returns.
The caller of cros_ec_get_host_event_wake_mask() ignores this, and so
for example, on EC's where the command is not implemented, we're using
junk (or in practice, all zeros) for our wake-mask. We should be using a
non-zero default (currently, it's supposed to be all-1's).
Fix this by checking the ->result field and returning -EPROTO for
errors.
I might label this as fixing commit 29d99b966d60 ("cros_ec: Don't signal
wake event for non-wake host events"), except that this fix alone
actually may make things worse, as it now allows for a lot more spurious
wakeups. The patch "platform/chrome: cros_ec_proto: ignore battery/AC
wakeups on old ECs" helps to mitigate this.
Signed-off-by: Brian Norris <briannor...@chromium.org>
---
drivers/platform/chrome/cros_ec_proto.c | 13 +++++++++++++
1 file changed, 13 insertions(+)
diff --git a/drivers/platform/chrome/cros_ec_proto.c
b/drivers/platform/chrome/cros_ec_proto.c
index e93024b55ce8..01a74abe4191 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -208,6 +208,12 @@ static int cros_ec_get_host_event_wake_mask(struct
cros_ec_device *ec_dev,
msg->insize = sizeof(*r);
ret = send_command(ec_dev, msg);
+ if (ret >= 0) {
+ if (msg->result == EC_RES_INVALID_COMMAND)
+ return -ENOTSUPP;
+ if (msg->result != EC_RES_SUCCESS)
+ return -EPROTO;
+ }
if (ret > 0) {
r = (struct ec_response_host_event_mask *)msg->data;
*mask = r->mask;
@@ -488,6 +494,13 @@ int cros_ec_query_all(struct cros_ec_device *ec_dev)
BIT(EC_HOST_EVENT_BATTERY_CRITICAL) |
BIT(EC_HOST_EVENT_PD_MCU) |
BIT(EC_HOST_EVENT_BATTERY_STATUS));
+ /*
+ * Old ECs may not support this command. Complain about all
+ * other errors.
+ */
+ if (ret != -ENOTSUPP)
+ dev_err(ec_dev->dev,
+ "failed to retrieve wake mask: %d\n", ret);
}
ret = 0;
--
2.28.0.rc0.105.gf9edc3c819-goog
