Re: dma_ops->map_page == NULL

On Jul 7, 2009, at 6:08 AM, Benjamin Herrenschmidt wrote:

On Tue, 2009-07-07 at 10:15 +1000, Mark Nelson wrote:

quoted

When the 32 and 64bit DMA code was merged in .28 , map_/ 
unmap_page() was
added in favour of map_/unmap_single() (which was later removed in . 
29)
so you'll have to replace your calls to dma_map_single() with
dma_map_page(). Just pass it the page and offset rather than the  
address.

Wait a minute ... dma_map_single() should still work, it will just  
call
dma_map_page() underneath. All dma_ops should have a ->map page
callback.

Do you have any dma_ops set for your device at all ? I wonder how we
set the dma_ops for platform devices nowadays ... We use to have this
fallback to direct ops when the dma_ops are NULL but that is gone and
I see no suitable replacement to set them on platform devices for
embedded archs ... oops...

Kumar, Becky, what's the situation there ?

Cheers,
Ben.

Is it possible the dev pointer is not valid?  I can't remember if that  
was a .29 or .30 change that requires us to start passing a valid dev  
pointer to get the proper dma_ops.

- k