Re: [FAIL bisect] Sound card probe error

From: Ulf Hansson <ulf.hansson@linaro.org>
To: Krzysztof Kozlowski <krzk@kernel.org>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	"Rafael J. Wysocki" <rafael.j.wysocki@intel.com>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Mark Brown <broonie@kernel.org>, Inki Dae <inki.dae@samsung.com>,
	"linux-samsung-soc@vger.kernel.org"
	<linux-samsung-soc@vger.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux ARM <linux-arm-kernel@lists.infradead.org>,
	Andrzej Hajda <a.hajda@samsung.com>
Subject: Re: [FAIL bisect] Sound card probe error
Date: Mon, 14 May 2018 16:35:52 +0200	[thread overview]
Message-ID: <CAPDyKFqdp=pL6HB_wYUofNX=ueF=pkMQ4+ptS8okpFxg7pvV9w@mail.gmail.com> (raw)
In-Reply-To: <CAJKOXPcTQX82UdcBROBc18C-M0_3bOnStLqJzUzRDqHC33m-1g@mail.gmail.com>

On 14 May 2018 at 14:43, Krzysztof Kozlowski <krzk@kernel.org> wrote:
> On Mon, May 14, 2018 at 2:30 PM, Ulf Hansson <ulf.hansson@linaro.org> wrote:
>> On 14 May 2018 at 14:22, Sylwester Nawrocki <s.nawrocki@samsung.com> 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@linaro.org>
>>>> 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@linaro.org>
>>>>     Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
>>>>     Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
>>>
>>> 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@linaro.org>
>> 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@kernel.org>
>> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
>> ---
>>  drivers/base/power/common.c | 2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>
>
> Yes, this fixes the issue.
> Tested-by: Krzysztof Kozlowski <krzk@kernel.org>

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