On 27/05/2022 08:54, Yihao Han wrote: > clk_unregister() already checks the clk ptr using > !clk || WARN_ON_ONCE(IS_ERR(clk)) so there is no need to check it > again before calling it. > No, this explanation does not make sense. clk_unregister() warns and this code is not equivalent. Best regards, Krzysztof