Messages in this thread | | | Date | Fri, 06 Jun 2014 19:21:38 +0300 | From | Eli Billauer <> | Subject | Re: [PATCH v2 1/4] dma-mapping: Add devm_ interface for dma_map_single() |
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On 06/06/14 19:01, Greg KH wrote: >> Please try to put yourself in my position: I have a driver that I care >> > about, which works fine for a few years. It's based upon dma_map_single(), >> > which seems to be the common way to get non-coherent memory, even for the >> > driver's entire lifespan. I realize that dma_alloc_* was the intended way to >> > do it, but fact is that dma_map_* has become the common choice. >> > Is your driver in the kernel tree? If not, you really are on your own :( > It's the Xillybus driver in the staging area. I don't know if this counts for being in the kernel tree...
The suggested patchset would allow replacing my use of dma_map_single() with a managed version of that function. This will clean the driver's code considerably.
But I think that the discussion here is if it's valid to use dma_map_single() for a device-permanent DMA mapping, or if dma_alloc_noncoherent() is the only way. If the answer is no, there's quite obviously no point in a devres version for that function.
Regards, Eli > greg k-h > >
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