Re: [FAIL bisect] Sound card probe error

From: Ulf Hansson
Date: Mon May 14 2018 - 10:36:00 EST


On 14 May 2018 at 14:43, Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
> On Mon, May 14, 2018 at 2:30 PM, Ulf Hansson <ulf.hansson@xxxxxxxxxx> wrote:
>> On 14 May 2018 at 14:22, Sylwester Nawrocki <s.nawrocki@xxxxxxxxxxx> wrote:
>>> Hi,
>>>
>>> On 05/14/2018 12:17 PM, Krzysztof Kozlowski wrote:
>>>
>>>> Bisected to:
>>>> 8c123c14bbba4add148536b6d47a9226deda2f7a is the first bad commit
>>>> commit 8c123c14bbba4add148536b6d47a9226deda2f7a
>>>> Author: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>>>> Date: Thu Apr 26 10:53:06 2018 +0200
>>>>
>>>> driver core: Respect all error codes from dev_pm_domain_attach()
>>>>
>>>> The limitation of being able to check only for -EPROBE_DEFER from
>>>> dev_pm_domain_attach() has been removed. Hence let's respect all error
>>>> codes and bail out accordingly.
>>>>
>>>> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>>>> Acked-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
>>>> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>>>
>>> The DRM driver creates the HDMI codec but its registration fails, due
>>> to some missing clocks. The clock are missing because the exynos5-subcmu
>>> driver probing fails.
>>>
>>> [ 0.678578] exynos5-subcmu: probe of GSC failed with error -17
>>> [ 0.679250] exynos5-subcmu: probe of MFC failed with error -17
>>> [ 0.679992] exynos5-subcmu: probe of DISP failed with error -17
>>>
>>> The exynos5-subcmu driver before registering platform device makes
>>> of_genpd_add_device() call, so in platform_drv_probe() dev_pm_domain_attach()
>>> call will fail, as dev->pm_domain is already set. Previously the error
>>> was masked by code removed in the above commit and platform_drv_probe()
>>> was could complete successfully.
>>
>> Thanks for providing this information!
>>
>> I was about to tell that I overlooked the fact that there is more than
>> one way to assign PM domain pointers to devices. To fix the problem,
>> dev_pm_domain_attach() should return 0, not -EEXIST when it finds and
>> existing PM domain pointer.
>>
>> Does the below patch fix the problem?
>>
>> From: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>> Date: Mon, 14 May 2018 14:26:16 +0200
>> Subject: [PATCH] PM / Domains: Don't return -EEXIST at attach when PM domain
>> exists
>>
>> As dev_pm_domain_attach() isn't the only way to assign PM domain pointers
>> to devices, clearly we must allow a device to have the pointer already
>> being assigned. For this reason, return 0 instead of -EEXIST.
>>
>> Reported-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>
>> Signed-off-by: Ulf Hansson <ulf.hansson@xxxxxxxxxx>
>> ---
>> drivers/base/power/common.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>
>
> Yes, this fixes the issue.
> Tested-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>

Thanks for the confirmation!

I am going to re-post the patch to include linux-pm, then let's see
how Rafael wants to handle it.

Kind regards
Uffe