Alsa-Devel Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: "Harsha priya gupta" <harshapriya@gmail.com>
To: Takashi Iwai <tiwai@suse.de>
Cc: Alsa-devel <alsa-devel@alsa-project.org>
Subject: Re: basic question on .pointer function
Date: Fri, 9 May 2008 23:51:17 +0530	[thread overview]
Message-ID: <827ad74d0805091121u4c42d172yc2b8e734355ff81d@mail.gmail.com> (raw)
In-Reply-To: <s5hwsm321ag.wl%tiwai@suse.de>

Thanks a lot for this pointer. A quick question;

For the .pointer function, it says " This callback is called when the PCM
middle layer inquires the current hardware position on the buffer."

Does the word "PCM middle layer" mean that the MMF like Helix / Gstreamer is
continuously querying for hardware position on the buffer? Or does the
player keep querying?

I also see that this function gets called quiet a number of times. Is there
a way to reduce these calls? My guess is that to reduce the number of calls
to .pointer, MMF or player needs to be modified. Am I thinking right?

-Harsha



On Fri, May 9, 2008 at 4:26 PM, Takashi Iwai <tiwai@suse.de> wrote:

> At Wed, 7 May 2008 09:10:00 +0530,
> Harsha priya gupta wrote:
> >
> > Hi,
> > It would be really helpful if someone can help me understand why do we
> need
> > to implement .pointer and what does it need to do? I am facing an issue
> to
> > write a driver in this .pointer function. Please help
> >
> > Also if someone can point me to a document where all the playback_ops are
> > defined, it would be really helpful
>
> Did you check the page below?
>
> http://www.alsa-project.org/main/index.php/ALSA_Driver_Documentation
>
>
> Takashi
>



-- 
-Harsha

  reply	other threads:[~2008-05-09 18:21 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-05-07  3:40 basic question on .pointer function Harsha priya gupta
2008-05-09 10:56 ` Takashi Iwai
2008-05-09 18:21   ` Harsha priya gupta [this message]
2008-05-13 13:44     ` 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=827ad74d0805091121u4c42d172yc2b8e734355ff81d@mail.gmail.com \
    --to=harshapriya@gmail.com \
    --cc=alsa-devel@alsa-project.org \
    --cc=tiwai@suse.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox