[PATCH] i2c: exynos5: Fix getting the optional clock

[Sam Protsenko]

"hsi2c_pclk" clock is optional and may not be present for some SoCs
supported by this driver. Nevertheless, in case the clock is provided
but some error happens during its getting, that error should be handled
properly. Use devm_clk_get_optional() API for that. Also report possible
errors using dev_err_probe() to handle properly -EPROBE_DEFER error (if
clock provider is not ready by the time I2C probe function is executed).

Fixes: c93ac09df2a8 ("i2c: exynos5: Add bus clock support")
Signed-off-by: Sam Protsenko <semen.protsenko at linaro.org>
---
 drivers/i2c/busses/i2c-exynos5.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/i2c/busses/i2c-exynos5.c b/drivers/i2c/busses/i2c-exynos5.c
index 693903e80892..b812d1090c0f 100644
--- a/drivers/i2c/busses/i2c-exynos5.c
+++ b/drivers/i2c/busses/i2c-exynos5.c
@@ -814,9 +814,11 @@ static int exynos5_i2c_probe(struct platform_device *pdev)
 		return -ENOENT;
 	}
 
-	i2c->pclk = devm_clk_get(&pdev->dev, "hsi2c_pclk");
-	if (IS_ERR(i2c->pclk))
-		i2c->pclk = NULL; /* pclk is optional */
+	i2c->pclk = devm_clk_get_optional(&pdev->dev, "hsi2c_pclk");
+	if (IS_ERR(i2c->pclk)) {
+		return dev_err_probe(&pdev->dev, PTR_ERR(i2c->pclk),
+				     "cannot get pclk");
+	}
 
 	ret = clk_prepare_enable(i2c->pclk);
 	if (ret)
-- 
2.30.2