linux-kernel - Re: [PATCHv5] DMAEngine: Define interleaved transfer request api

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Fri, 14 Oct 2011 21:39:20 +0530
From:	Vinod Koul <vinod.koul@...el.com>
To:	Barry Song <21cnbao@...il.com>
Cc:	Jassi Brar <jaswinder.singh@...aro.org>,
	linux-kernel@...r.kernel.org, dan.j.williams@...el.com,
	rmk@....linux.org.uk,
	DL-SHA-WorkGroupLinux <workgroup.linux@....com>
Subject: Re: [PATCHv5] DMAEngine: Define interleaved transfer request api

On Fri, 2011-10-14 at 23:38 +0800, Barry Song wrote:
> Vinod, actually it is not decided by codec. it is only related with
> the hardware of pcm, i2s or AC'97 controllers in SoC. i did remember
> some people  once licensed a TDM tranfer enginee from synopsys and IC
> guys bound one TDM slot, which has a seperate  dma channel, to one
> audio channel then organize several TDM slots into a AC97 controller.
Not sure if I follow you.
For i2s and pcm you send left/right channel and then right/left channel.
Data is sent interleaved. DMA also treats it same way.
I don't know about AC97 so wont comment about it
> 
> i am on holiday now and i can't give you more information until next
> week.
> 
> Still i saw most other chips binding multi-channels of an I2S/PCM/AC97
> audio controller in a dma channel, then it doesn't need interleaved
> dma api as its dma address will increase continuously. dma will
> transfer left+right together but not one left and one right.
Right :)

-- 
~Vinod

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/