From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Harsha priya gupta" Subject: Re: basic question on .pointer function Date: Fri, 9 May 2008 23:51:17 +0530 Message-ID: <827ad74d0805091121u4c42d172yc2b8e734355ff81d@mail.gmail.com> References: <827ad74d0805062040i4c2977adrc4fb50fbbc0bff43@mail.gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from an-out-0708.google.com (an-out-0708.google.com [209.85.132.240]) by alsa0.perex.cz (Postfix) with ESMTP id F353024391 for ; Fri, 9 May 2008 20:21:18 +0200 (CEST) Received: by an-out-0708.google.com with SMTP id d31so339316and.80 for ; Fri, 09 May 2008 11:21:17 -0700 (PDT) In-Reply-To: Content-Disposition: inline List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: alsa-devel-bounces@alsa-project.org Errors-To: alsa-devel-bounces@alsa-project.org To: Takashi Iwai Cc: Alsa-devel List-Id: alsa-devel@alsa-project.org 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 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