Re: [PATCH v2 2/2] spi: spi-geni-qcom: Fix missing undo runtime PM changes at driver exit time

[Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>]

On Fri, 6 Sept 2024 at 06:41, Jinjie Ruan <ruanjinjie@xxxxxxxxxx> wrote:
>
>
>
> On 2024/9/6 11:36, Dmitry Baryshkov wrote:
> > On Fri, 6 Sept 2024 at 06:31, Jinjie Ruan <ruanjinjie@xxxxxxxxxx> wrote:
> >>
> >>
> >>
> >> On 2024/9/6 11:15, Dmitry Baryshkov wrote:
> >>> On Fri, Sep 06, 2024 at 11:13:45AM GMT, Jinjie Ruan wrote:
> >>>> It's important to undo pm_runtime_use_autosuspend() with
> >>>> pm_runtime_dont_use_autosuspend() at driver exit time unless driver
> >>>> initially enabled pm_runtime with devm_pm_runtime_enable()
> >>>> (which handles it for you).
> >>>>
> >>>> Hence, call pm_runtime_dont_use_autosuspend() at driver exit time
> >>>> to fix it.
> >>>>
> >>>> Fixes: cfdab2cd85ec ("spi: spi-geni-qcom: Set an autosuspend delay of 250 ms")
> >>>> ---
> >>>> v2:
> >>>> - Fix it directly instead of use devm_pm_runtime_enable().
> >>>
> >>> Why?
> >>
> >> The devm* sequence will have some problem, which will not consistent
> >> with the former.
> >>
> >> Link:
> >> https://lore.kernel.org/all/CAD=FV=VyDk-e2KNiuiBcACFAdrQmihOH6X6BSpGB+T1MsgsiKw@xxxxxxxxxxxxxx/
> >
> > That comment was for devm_request_irq(), not devm_pm_runtime_enable().
>
>
> In the very least, ** parch #2 needs to come before this one and that
> would help, but it won't fix everything **. Specifically in order to
> keep the order proper you'll need to use devm_add_action_or_reset() to
> "devm-ize" the freeing of the DMA channels.

This is patch #2. so I don't understand your comment. Moreover you
don't have to use devm for each and every possible item. However I
think it makes sense for pm_runtime in this case.

>
>
> >
> >>
> >>>
> >>>> ---
> >>>>  drivers/spi/spi-geni-qcom.c | 2 ++
> >>>>  1 file changed, 2 insertions(+)
> >>>>
> >>>> diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
> >>>> index fc2819effe2d..38857edbc785 100644
> >>>> --- a/drivers/spi/spi-geni-qcom.c
> >>>> +++ b/drivers/spi/spi-geni-qcom.c
> >>>> @@ -1158,6 +1158,7 @@ static int spi_geni_probe(struct platform_device *pdev)
> >>>>  spi_geni_release_dma:
> >>>>      spi_geni_release_dma_chan(mas);
> >>>>  spi_geni_probe_runtime_disable:
> >>>> +    pm_runtime_dont_use_autosuspend(dev);
> >>>>      pm_runtime_disable(dev);
> >>>>      return ret;
> >>>>  }
> >>>> @@ -1174,6 +1175,7 @@ static void spi_geni_remove(struct platform_device *pdev)
> >>>>
> >>>>      spi_geni_release_dma_chan(mas);
> >>>>
> >>>> +    pm_runtime_dont_use_autosuspend(&pdev->dev);
> >>>>      pm_runtime_disable(&pdev->dev);
> >>>>  }
> >>>>
> >>>> --
> >>>> 2.34.1
> >>>>
> >>>
> >
> >
> >



-- 
With best wishes
Dmitry