void * usb_ep_alloc_buffer (struct usb_ep * ep, unsigned len, dma_addr_t * dma, int gfp_flags);
Returns a new buffer, or null if one could not be allocated. The buffer is suitably aligned for dma, if that endpoint uses DMA, and the caller won't have to care about dma-inconsistency or any hidden ``bounce buffer'' mechanism. No additional per-request DMA mapping will be required for such buffers. Free it later with usb_ep_free_buffer.
You don't need to use this call to allocate I/O buffers unless you want to make sure drivers don't incur costs for such ``bounce buffer'' copies or per-request DMA mappings.
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This documentation was generated with kernel version 2.5.73.