Re: [PATCH] PCI: Do not enable async suspend for JMicron chips

[Aaron Lu <aaron.lu@intel.com>]

On 11/06/2014 01:29 PM, Liu, Chuansheng wrote:
> Hello Bjorn,
> 
>> -----Original Message-----
>> From: Bjorn Helgaas [mailto:bhelgaas@google.com]
>> Sent: Thursday, November 06, 2014 12:09 PM
>> To: Liu, Chuansheng
>> Cc: Barto; Tejun Heo (tj@kernel.org); Lu, Aaron; Rafael Wysocki;
>> linux-pci@vger.kernel.org; linux-kernel@vger.kernel.org
>> Subject: Re: [PATCH] PCI: Do not enable async suspend for JMicron chips
>>
>> On Wed, Nov 5, 2014 at 6:48 PM, Liu, Chuansheng
>> <chuansheng.liu@intel.com> wrote:
>>> Hello Bjorn,
>>>
>>>> -----Original Message-----
>>>> From: Bjorn Helgaas [mailto:bhelgaas@google.com]
>>>> Sent: Thursday, November 06, 2014 3:04 AM
>>>> To: Barto
>>>> Cc: Liu, Chuansheng; Lu, Aaron; Tejun Heo; Rafael Wysocki;
>>>> linux-pci@vger.kernel.org; linux-kernel@vger.kernel.org
>>>> Subject: Re: [PATCH] PCI: Do not enable async suspend for JMicron chips
>>>>
>>>> On Wed, Nov 5, 2014 at 11:46 AM, Barto <mister.freeman@laposte.net>
>>>> wrote:
>>>>> this patch solves these 2 bug reports :
>>>>>
>>>>> https://bugzilla.kernel.org/show_bug.cgi?id=84861
>>>>>
>>>>> https://bugzilla.kernel.org/show_bug.cgi?id=81551
>>>>
>>>> Those bugs were already mentioned.  But e6b7e41cdd8c claims to solve
>>>> https://bugzilla.kernel.org/show_bug.cgi?id=81551, and 84861 is a
>>>> duplicate of 81551, so it should also be fixed by e6b7e41cdd8c.
>>>>
>>>> So the question is, why was e6b7e41cdd8c insufficient?  Presumably it
>>>> was tested and somebody thought it did fix the problem.
>>>
>>> The first patch e6b7e41cdd8c which is just exclude some of JMicron
>> chips(363/361) out of async_suspend,
>>> then Barto found the same issue on JMicron 368, so we need one more
>> general patch to let JMicron chips
>>> out of async_suspend, so we make this patch.
>>>
>>> Bjorn, tj,
>>> Could you kindly take this patch? As Barto said, it effected the user
>> experience indeed, thanks.
>>
>> Thanks for clarifying the changelog as far as the different chips and
>> the different bugzillas.
>>
>> But you haven't addressed my concerns about (1) putting a PCI vendor
>> ID check in the generic PCI core code, and (2) applying this to *all*
>> JMicron devices.  You might want to explore a quirk-type solution or
>> maybe just add the JMicron 368 to the checks added by e6b7e41cdd8c.
> Understand your point, in fact, before this patch submitted, I had written another patch https://lkml.org/lkml/2014/9/24/68
> which addressed to add the quirk-type solution in ATA code, and Aaron given better suggestion that implemented at pci_pm_init().
> How do you think of it? Thanks.

I think Bjorn means that we should place the code as a fixup somewhere
in the quirks.c. I didn't take a closer look but DECLARE_PCI_FIXUP_FINAL
for those JMicron PCI devices seems to be a proper phase.

Thanks,
Aaron