Re: [PATCH v1] PM / devfreq: exynos-ppmu : Handle return value of clk_prepare_enable

From: Chanwoo Choi
Date: Tue May 23 2017 - 21:55:02 EST


On 2017ë 05ì 24ì 10:30, MyungJoo Ham wrote:
>> On 2017ë 05ì 19ì 19:56, Arvind Yadav wrote:
>>> clk_prepare_enable() can fail here and we must check its return value.
>>>
>>> Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
>>> ---
>>> 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@xxxxxxxxxxx>

--
Best Regards,
Chanwoo Choi
Samsung Electronics