RFC bus_dma_tag_parent

[Matthew Dillon]

:
:This has come up a couple times recently*, so here's a proposal as to
:one way of fixing the problem in the bus_dma API
:
:...
:  bus_dma_tag_parent(dev)
:
:  Returns the DMA tag of the bus dev connects to. Drivers can use the
:  DMA tag for the parent parameter in subsequent calls to
:  bus_dma_tag_create(9). All devices on a bus share this tag as their
:  parent and should not destroy it.
:
:  Returns NULL if tag does not exist or a bus_dma_tag_t on success.
:
:
:If this is the type of fix you were thinking of, I'll go ahead and
:code something up for PCI devices.
:
:* http://leaf.dragonflybsd.org/mailarchive/bugs/2004-10/msg00050.html
:-- 
:Chuck Tuffli
:Agilent Technologies

    I like it, Chuck.  I think it is a good solution.

					-Matt
					Matthew Dillon 
					<dillon at xxxxxxxxxxxxx>