Hi Thierry, On 2016?06?04? 00:54, Thierry Reding wrote: > On Fri, Jun 03, 2016 at 05:55:17PM +0800, Lin Huang wrote: > [...] >> + ret = clk_prepare_enable(data->clk); >> + if (ret) { >> + dev_err(&pdev->dev, "failed to enable clk: %d\n", ret); >> + clk_disable_unprepare(data->clk); >> + return ret; >> + } > This is going to give you a large WARN. clk_prepare_enable() already > leaves the clock in a proper state when it fails (i.e. it calls > clk_unprepare() if the clk_enable() part failed), so calling > clk_disable_unprepare() upon failure is going to unbalance the > reference counts. Thanks for reminding, i will fix it next version. > > Thierry -- Lin Huang