From: Mauro Carvalho Chehab <mchehab@redhat.com>
To: Fabio Estevam <festevam@gmail.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>,
linux-media@vger.kernel.org, mchehab@infradead.org,
kernel@pengutronix.de,
Fabio Estevam <fabio.estevam@freescale.com>
Subject: Re: [PATCH] video: mx3_camera: Allocate camera object via kzalloc
Date: Mon, 19 Mar 2012 23:01:33 -0300 [thread overview]
Message-ID: <4F67E4FD.2070709@redhat.com> (raw)
In-Reply-To: <CAOMZO5AAeqHZFqpZYB_riSCQvCRSjQtR2EqpZvC5V3TRyzuWJQ@mail.gmail.com>
Em 20-02-2012 16:23, Fabio Estevam escreveu:
> On Mon, Feb 20, 2012 at 4:17 PM, Guennadi Liakhovetski
> <g.liakhovetski@gmx.de> wrote:
>> On Mon, 20 Feb 2012, Fabio Estevam wrote:
>>
>>> Align mx3_camera driver with the other soc camera driver implementations
>>> by allocating the camera object via kzalloc.
>>
>> Sorry, any specific reason, why you think this "aligning" is so important?
>
> Not really.
>
> Just compared it with all other soc camera drivers I found and
> mx3_camera was the only one that uses "vzalloc"
>
> Any specific reason that requires mx3_camera to use "vzalloc" instead
> of "kzalloc"?
kzalloc() is more restrictive than vzalloc(). With v*alloc, it will allocate
a virtual memory area, with can be discontinuous, while kzalloc will get
a continuous area.
The DMA logic need to be prepared for virtual memory, if v*alloc() is used
(e. g. using videobuf2-vmalloc).
As it is currently including media/videobuf2-dma-contig.h, I this patch
makes sense on my eyes.
>
> Tested with kzalloc and it worked fine on my mx31pdk.
If the driver is working with vzalloc, then maybe it is due to some arch-specific
implementation for v*alloc. It shouldn't be working like that.
Regards,
Mauro
>
> Regards,
>
> Fabio Estevam
> --
> To unsubscribe from this list: send the line "unsubscribe linux-media" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2012-03-20 2:02 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-02-20 18:11 [PATCH] video: mx3_camera: Allocate camera object via kzalloc Fabio Estevam
2012-02-20 18:17 ` Guennadi Liakhovetski
2012-02-20 18:23 ` Fabio Estevam
2012-03-20 2:01 ` Mauro Carvalho Chehab [this message]
2012-03-20 7:57 ` Guennadi Liakhovetski
2012-03-20 12:37 ` Fabio Estevam
2012-03-20 12:40 ` Guennadi Liakhovetski
2012-03-20 12:45 ` Fabio Estevam
2012-03-20 13:11 ` Guennadi Liakhovetski
2012-03-20 13:20 ` AverTV Volar HD PRO : a return case Sril
2012-03-20 12:53 ` [PATCH] video: mx3_camera: Allocate camera object via kzalloc Mauro Carvalho Chehab
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=4F67E4FD.2070709@redhat.com \
--to=mchehab@redhat.com \
--cc=fabio.estevam@freescale.com \
--cc=festevam@gmail.com \
--cc=g.liakhovetski@gmx.de \
--cc=kernel@pengutronix.de \
--cc=linux-media@vger.kernel.org \
--cc=mchehab@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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.