bus_get_dma_tag now necessary for drivers using bus_dma

[Poul-Henning Kamp]

In message <20060905173334.GH9421 at funkthat.com>, John-Mark Gurney writes:

>This means that for each call to bus_dma_tag_create, instead of passing
>a NULL pointer, you should call bus_get_dma_tag(yourdev) and use that
>as the parent tag.  I committed some example code to various drivers,
>such as ahc, ata, em, and ohci.

If there are never any exeptions to this requirement, why not
pass "yourdev" and have the magic hidden, rather than add 17
ritual characters to the API ?

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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Never attribute to malice what can adequately be explained by incompetence.