Re: [PATCH] devfreq: tegra: fix error code in tegra_devfreq_probe()

From: Jon Hunter
Date: Mon Jul 03 2017 - 08:22:22 EST



On 03/07/17 12:59, Gustavo A. R. Silva wrote:
> Hi Jon,
>
> Quoting Jon Hunter <jonathanh@xxxxxxxxxx>:
>
>> On 30/06/17 08:22, Gustavo A. R. Silva wrote:
>>> Print and propagate the return value of platform_get_irq on failure.
>>>
>>> Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
>>> ---
>>> drivers/devfreq/tegra-devfreq.c | 6 +++---
>>> 1 file changed, 3 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/devfreq/tegra-devfreq.c
>>> b/drivers/devfreq/tegra-devfreq.c
>>> index 214fff9..ae71215 100644
>>> --- a/drivers/devfreq/tegra-devfreq.c
>>> +++ b/drivers/devfreq/tegra-devfreq.c
>>> @@ -688,9 +688,9 @@ static int tegra_devfreq_probe(struct
>>> platform_device *pdev)
>>> }
>>>
>>> irq = platform_get_irq(pdev, 0);
>>> - if (irq <= 0) {
>>> - dev_err(&pdev->dev, "Failed to get IRQ\n");
>>> - return -ENODEV;
>>> + if (irq < 0) {
>>
>> The changelog does not describe the above change and if/why this is ok.
>> However, the original test looks fine to me and so I don't see a need to
>> change this.
>>
>
> You are right about the changelog. I think this one is much better:
>
> platform_get_irq() returns an error code, but the tegra-devfreq
> driver ignores it and always returns -ENODEV. This is not correct,
> and prevents -EPROBE_DEFER from being propagated properly.
>
> Notice that platform_get_irq() no longer returns 0 on error:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=e330b9a6bb35dc7097a4f02cb1ae7b6f96df92af

Yes the above should be added to the changelog.

Looks like someone should update the following for consistency too ...

141 int platform_irq_count(struct platform_device *dev)
142 {
143 int ret, nr = 0;
144
145 while ((ret = platform_get_irq(dev, nr)) >= 0)
146 nr++;

>
> Print error message and propagate the return value of
> platform_get_irq on failure.
>
> What do you think?
Fine with me.

Thanks!
Jon

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