On 2017? 05? 24? 10:30, MyungJoo Ham wrote:

quoted

On 2017? 05? 19? 19:56, Arvind Yadav wrote:

quoted

clk_prepare_enable() can fail here and we must check its return value.

Signed-off-by: Arvind Yadav <redacted>
---
 drivers/devfreq/event/exynos-ppmu.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
index 9b73509..8f6537a 100644
--- a/drivers/devfreq/event/exynos-ppmu.c
+++ b/drivers/devfreq/event/exynos-ppmu.c

@@ -648,7 +648,11 @@ static int exynos_ppmu_probe(struct platform_device *pdev)
 			dev_name(&pdev->dev), desc[i].name);
 	}
 
-	clk_prepare_enable(info->ppmu.clk);
+	ret = clk_prepare_enable(info->ppmu.clk);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to prepare ppmu clock\n");
+		return ret;
+	}

You're right. But, actually, some ppmu device-tree node doesn't include
the clock information because exynos clk driver don't support the
clock for some ppmu devices. Until now, the clock of ppmu devices
are default on state.

If it does not include the clock information, info->ppmu.clk is NULL,
which makes ret == NULL, so this should be ok.
(Line 593 of this file does that.)

Ah.. You're right. I'm missing this point.

Looks good to me.
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>

-- 
Best Regards,
Chanwoo Choi
Samsung Electronics