Date: Tue, 22 Oct 1996 10:03:16 -0400 From: Alexander Seth Jones <ajones@ctron.com> To: hackers@freefall.freebsd.org Subject: DMA and autoinitialize Message-ID: <326CD424.7085@ctron.com>
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I'm writing a device driver for an audio card and would like to autoinitialize the DMA. Right now, I do this using isa_dmastart. However, I don't see any routines to grab the data periodically to place it in a buffer inside my driver. I can't use isa_dmadone, because if a bounce buffer is being used, it'll flag it as not being used anymore, so I won't be able to get anymore data. What makes things tough is that the interrupt on the card is not tied to DMA in hardware, so I have to poll the DMA controller periodically to see how many bytes I can transfer over to an internal buffer. I looked through all the drivers and didn't see anybody even doing any autoinitialization, nor did I see a routine to periodically grab stuff from the DMA buffer (2.1.5-RELEASE) Does such a routine exist? or will I have to write one? or can someone suggest another way to approach this? Thanks. -- Alex Jones | ajones@ctron.com Cabletron Systems, Inc. Durham, NH USA 03824
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