[ Upstream commite6df0f649c] wait_for_completion_timeout() returns the remaining jiffies (at least 1) on success or 0 on timeout, but never negative error codes. The current code incorrectly checks for negative values, causing timeouts to be ignored and treated as success. Check for a zero return value to correctly identify and handle timeout events. Fixes:0cf7befa3e("greybus: gb-beagleplay: Add firmware upload API") Signed-off-by: Haotian Zhang <vulab@iscas.ac.cn> Link: https://patch.msgid.link/20251121064027.571-1-vulab@iscas.ac.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>