linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: okaya@codeaurora.org (okaya at codeaurora.org)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH V3 1/3] vfio, platform: add support for ACPI while detecting the reset driver
Date: Tue, 29 Mar 2016 06:59:15 -0400	[thread overview]
Message-ID: <e736f6bc775cdca8a4bb0dab20654823@codeaurora.org> (raw)
In-Reply-To: <98854818.NJS35fvhsb@wuerfel>

On 2016-03-29 05:25, Arnd Bergmann wrote:
> On Monday 28 March 2016 09:35:22 Sinan Kaya wrote:
>> The code is using the compatible DT string to associate a reset driver 
>> with
>> the actual device itself. The compatible string does not exist on ACPI
>> based systems. HID is the unique identifier for a device driver 
>> instead.
>> The change allows a driver to register with DT compatible string or 
>> ACPI
>> HID and then match the object with one of these conditions.
>> 
>> Rules for loading the reset driver are as follow:
>> - ACPI HID needs match for ACPI systems
>> - DT compat needs to match for OF systems
>> 
>> Tested-by: Eric Auger <eric.auger@linaro.org> (device tree only)
>> Tested-by: Shanker Donthineni <shankerd@codeaurora.org> (ACPI only)
>> Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
>> 
> 
> 
> This really feels wrong for two reasons:
> 
> * device assignment of non-PCI devices is really special and doesn't
>   seem to make sense on general purpose servers that would be the 
> target
>   for ACPI normally


Why is it special? Acpi is not equal to pci. Platform devices are first 
class devices too. Especially, _cls was introduced for this reason.


> 
> * If there is indeed a requirement for ACPI to handle something like 
> this,
>   it should be part of the ACPI spec, with a well-defined method of 
> handling
>   reset, rather than having to add a device specific hack for each
>   device separately.
> 

I see. Normally, this is done by calling _rst method. AFAIK, Linux 
doesn?t support _rst. I can check its presence and call it if it is 
there.



> 	Arnd

  reply	other threads:[~2016-03-29 10:59 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-03-28 13:35 [PATCH V3 0/3] vfio, platform: add HIDMA and ACPI support Sinan Kaya
2016-03-28 13:35 ` [PATCH V3 1/3] vfio, platform: add support for ACPI while detecting the reset driver Sinan Kaya
2016-03-29  9:25   ` Arnd Bergmann
2016-03-29 10:59     ` okaya at codeaurora.org [this message]
2016-03-29 11:25       ` Arnd Bergmann
2016-03-29 12:15         ` okaya at codeaurora.org
2016-03-29 12:44           ` Arnd Bergmann
2016-05-01 17:55             ` Sinan Kaya
2016-03-28 13:35 ` [PATCH V3 2/3] vfio, platform: make reset driver a requirement by default Sinan Kaya
2016-03-28 13:35 ` [PATCH V3 3/3] vfio, platform: add QTI HIDMA reset driver Sinan Kaya

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=e736f6bc775cdca8a4bb0dab20654823@codeaurora.org \
    --to=okaya@codeaurora.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).