From: Adrian Knoth <adi@drcomp.erfurt.thur.de>
To: Clemens Ladisch <clemens@ladisch.de>
Cc: alsa-devel@alsa-project.org
Subject: Re: Allocating DMA buffer for non-PCM
Date: Thu, 14 Feb 2013 18:52:51 +0100 [thread overview]
Message-ID: <20130214175251.GD15334@ltw.loris.tv> (raw)
In-Reply-To: <511D22F6.2060600@ladisch.de>
On Thu, Feb 14, 2013 at 06:46:30PM +0100, Clemens Ladisch wrote:
> > Would you say that the following is the proper way to allocate a DMA
> > buffer used to hold level data?
> >
> > err = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV_SG,
> > snd_dma_pci_data(hdspm->pci),
> > MADIFX_LEVEL_BUFFER_SIZE, &hdspm->dmaLevelBuffer);
> >
> > hdspm->level_buffer = snd_sgbuf_get_ptr(&(hdspm->dmaLevelBuffer), 0);
> I don't see the code asking for the address of the second page, so I
> guess there isn't one.
Exactly.
Just to be sure: Takashi has recommended to use
(u32*)dmaLevelBuffer.area. Even in the case of SG buffers, is this
virtual address continuous and safe for memset?
Cheers
--
mail: adi@thur.de http://adi.thur.de PGP/GPG: key via keyserver
next prev parent reply other threads:[~2013-02-14 17:52 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-14 17:03 Allocating DMA buffer for non-PCM Adrian Knoth
2013-02-14 17:14 ` Takashi Iwai
2013-02-14 17:26 ` Adrian Knoth
2013-02-15 6:22 ` Takashi Iwai
2013-02-14 17:46 ` Clemens Ladisch
2013-02-14 17:52 ` Adrian Knoth [this message]
2013-02-14 18:01 ` Clemens Ladisch
2013-02-14 18:46 ` Adrian Knoth
2013-02-15 9:04 ` Takashi Iwai
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=20130214175251.GD15334@ltw.loris.tv \
--to=adi@drcomp.erfurt.thur.de \
--cc=alsa-devel@alsa-project.org \
--cc=clemens@ladisch.de \
/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.