[PATCH] mfd: cros-ec: copy the whole event in get_next_event_xfer

From: Emil Karlson
Date: Fri Sep 28 2018 - 13:08:53 EST


Commit 57e94c8b974db2d83c60e1139c89a70806abbea0 caused cros-ec keyboard events
be truncated on many chromebooks so that Left and Right keys on Column 12 were
always 0. Use ret as memcpy len to fix this.

drivers/platform/chrome/cros_ec_proto.c:509
get_next_event_xfer uses ret from cros_ec_cmd_xfer for memcpy for msg->data len
drivers/platform/chrome/cros_ec_proto.c:445
cros_ec_cmd_xfer gets ret from send_command
drivers/platform/chrome/cros_ec_proto.c:93
send_command gets ret from bus specific xfer_fn
drivers/mfd/cros_ec_spi.c:598
cros_ec_cmd_xfer_spi copies len amount to ec_msg->data and returns len as ret
drivers/mfd/cros_ec_i2c.c:267
cros_ec_cmd_xfer_i2c copies len amount to ec_msg->data and returns len as ret

so msg->data length is always the same as ret.

Fixes: 57e94c8b974d ("mfd: cros-ec: Increase maximum mkbp event size")
Signed-off-by: Emil Karlson <jekarlson@xxxxxxxxx>
---
drivers/platform/chrome/cros_ec_proto.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
index 398393ab5df8..b6fd4838f60f 100644
--- a/drivers/platform/chrome/cros_ec_proto.c
+++ b/drivers/platform/chrome/cros_ec_proto.c
@@ -520,7 +520,7 @@ static int get_next_event_xfer(struct cros_ec_device *ec_dev,
ret = cros_ec_cmd_xfer(ec_dev, msg);
if (ret > 0) {
ec_dev->event_size = ret - 1;
- memcpy(&ec_dev->event_data, msg->data, ec_dev->event_size);
+ memcpy(&ec_dev->event_data, msg->data, ret);
}

return ret;
--
2.19.0