[PATCH] i2c: axxia: enable clock before calling clk_get_rate()

From: Tobias Jordan
Date: Mon Apr 30 2018 - 09:52:50 EST


axxia_i2c_init() uses clk_get_rate() for idev->i2c_clk. clk_get_rate()
should only be called if the clock is enabled, so ensure that by moving
the clk_prepare_enable() call before the call to axxia_i2c_init().

Found by Linux Driver Verification project (linuxtesting.org).

Fixes: 08678b850cd0 ("i2c: axxia: Add I2C driver for AXM55xx")
Signed-off-by: Tobias Jordan <Tobias.Jordan@xxxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-axxia.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/i2c/busses/i2c-axxia.c b/drivers/i2c/busses/i2c-axxia.c
index 13f07482ec68..51338c48d193 100644
--- a/drivers/i2c/busses/i2c-axxia.c
+++ b/drivers/i2c/busses/i2c-axxia.c
@@ -532,6 +532,12 @@ static int axxia_i2c_probe(struct platform_device *pdev)
if (idev->bus_clk_rate == 0)
idev->bus_clk_rate = 100000; /* default clock rate */

+ ret = clk_prepare_enable(idev->i2c_clk);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to enable clock\n");
+ return ret;
+ }
+
ret = axxia_i2c_init(idev);
if (ret) {
dev_err(&pdev->dev, "failed to initialize\n");
@@ -545,12 +551,6 @@ static int axxia_i2c_probe(struct platform_device *pdev)
return ret;
}

- ret = clk_prepare_enable(idev->i2c_clk);
- if (ret) {
- dev_err(&pdev->dev, "failed to enable clock\n");
- return ret;
- }
-
i2c_set_adapdata(&idev->adapter, idev);
strlcpy(idev->adapter.name, pdev->name, sizeof(idev->adapter.name));
idev->adapter.owner = THIS_MODULE;
--
2.11.0