Subject: Re: [RFC 0/2] staging: ion: of_ion_device_get
To: Moritz Fischer <moritz.fischer@ettus.com>, arnd@arndb.de
References: <1458686031-31031-1-git-send-email-moritz.fischer@ettus.com>
Cc: gregkh@linuxfoundation.org, arve@android.com, riandrews@android.com,
        gioh.kim@lge.com, sumit.semwal@linaro.org, dan.carpenter@oracle.com,
        sriram@marirs.net.in, linux-kernel@vger.kernel.org,
        devel@driverdev.osuosl.org
From: Laura Abbott <labbott@redhat.com>
Message-ID: <56F1CC7B.7040909@redhat.com>
Date: Tue, 22 Mar 2016 15:51:39 -0700
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On 03/22/2016 03:33 PM, Moritz Fischer wrote:
> Hi all,
>
> probably I'm doing this all wrong. I'm playing around with a bunch of accelerators
> and I need to share buffers between them. I have my heaps implemented as a
> platform device and from what I understand I'll need a reference to the
> struct ion_device in each of them.
> I couldn't find a way to get to that via devicetree, though. I'll admit that hacking
> up miscdevice is quite hacky, maybe I should add a foo_get_ion_device() to my
> heap implementing platform device?
> If someone can explain me how to correctly do that with what we currently have,
> even better.
>
> Cheers,
>
>     Moritz
>
> Moritz Fischer (2):
>    misc: Add of_get_misc get a reference from devicetree
>    staging: android: ion: Add of_ion_device_get function
>
>   drivers/char/misc.c               | 38 ++++++++++++++++++++++++++++++++++++++
>   drivers/staging/android/ion/ion.c | 10 ++++++++++
>   include/linux/miscdevice.h        |  3 +++
>   3 files changed, 51 insertions(+)
>

In the past what drivers have done is a foo_ion_client_create which has the reference
to the ion_device created from ion_device_create. Drivers then call the
foo_ion_client_create function.

Can you elaborate more on your sharing and allocation flow? This might suggest
another idea.

Thanks,
Laura