4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Stefan Potyra <Stefan.Potyra@xxxxxxxxxxxxxx> commit 955bc61328dc0a297fb3baccd84e9d3aee501ed8 upstream. According to the API, you may only call clk_get_rate() after actually enabling it. Found by Linux Driver Verification project (linuxtesting.org). Fixes: a5fd9139f74c ("w1: add 1-wire master driver for i.MX27 / i.MX31") Signed-off-by: Stefan Potyra <Stefan.Potyra@xxxxxxxxxxxxxx> Acked-by: Evgeniy Polyakov <zbr@xxxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/w1/masters/mxc_w1.c | 20 +++++++++++++------- 1 file changed, 13 insertions(+), 7 deletions(-) --- a/drivers/w1/masters/mxc_w1.c +++ b/drivers/w1/masters/mxc_w1.c @@ -113,6 +113,10 @@ static int mxc_w1_probe(struct platform_ if (IS_ERR(mdev->clk)) return PTR_ERR(mdev->clk); + err = clk_prepare_enable(mdev->clk); + if (err) + return err; + clkrate = clk_get_rate(mdev->clk); if (clkrate < 10000000) dev_warn(&pdev->dev, @@ -126,12 +130,10 @@ static int mxc_w1_probe(struct platform_ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); mdev->regs = devm_ioremap_resource(&pdev->dev, res); - if (IS_ERR(mdev->regs)) - return PTR_ERR(mdev->regs); - - err = clk_prepare_enable(mdev->clk); - if (err) - return err; + if (IS_ERR(mdev->regs)) { + err = PTR_ERR(mdev->regs); + goto out_disable_clk; + } /* Software reset 1-Wire module */ writeb(MXC_W1_RESET_RST, mdev->regs + MXC_W1_RESET); @@ -147,8 +149,12 @@ static int mxc_w1_probe(struct platform_ err = w1_add_master_device(&mdev->bus_master); if (err) - clk_disable_unprepare(mdev->clk); + goto out_disable_clk; + + return 0; +out_disable_clk: + clk_disable_unprepare(mdev->clk); return err; }