[HOWTO] accessing the DMA mapped data

From: Mahesh
Date: Thu May 10 2007 - 04:27:22 EST


Hi list,

I have a small question regarding the accessing the data in the DMA mapped region (in the driver). In my driver I only have the 'dma_addr_t addr' variable which is result after the 'dma_map_single'. I don't have access to the virtual address of the data region.

Is there helper routine which we will give me the virtual address back from the DMA mapped address???

After some searching in the net about it found 'dma_sync_single' which will help to synchronize it after 'modifying' the contents of the DMA mapped region. But to 'modify' the contents of DMA mapped region I require the virtual address, which is not available in my case.

Regards,
Mahesh.


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