[PATCH] Enable clock before calling clk_get_rate() on it.

From: Stefan Potyra
Date: Thu Apr 19 2018 - 09:13:02 EST


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>
---
drivers/w1/masters/mxc_w1.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/w1/masters/mxc_w1.c b/drivers/w1/masters/mxc_w1.c
index 74f2e6e6202a..a9599027d4ef 100644
--- a/drivers/w1/masters/mxc_w1.c
+++ b/drivers/w1/masters/mxc_w1.c
@@ -112,6 +112,10 @@ static int mxc_w1_probe(struct platform_device *pdev)
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,
@@ -128,10 +132,6 @@ static int mxc_w1_probe(struct platform_device *pdev)
if (IS_ERR(mdev->regs))
return PTR_ERR(mdev->regs);

- err = clk_prepare_enable(mdev->clk);
- if (err)
- return err;
-
/* Software reset 1-Wire module */
writeb(MXC_W1_RESET_RST, mdev->regs + MXC_W1_RESET);
writeb(0, mdev->regs + MXC_W1_RESET);
--
2.17.0