TononixOS/ubports_kernel_google_msm
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

usb gadget stack: remove usb_ep_*_buffer(), part 1

Browse Source 
Remove usb_ep_{alloc,free}_buffer() calls, for small dma-coherent buffers.
This patch just removes the interface and its users; later patches will
remove controller driver support.

  - This interface is invariably not implemented correctly in the
    controller drivers (e.g. using dma pools, a mechanism which
    post-dates the interface by several years).

  - At this point no gadget driver really *needs* to use it.  In
    current kernels, any driver that needs such a mechanism could
    allocate a dma pool themselves.

Removing this interface is thus a simplification and improvement.

Note that the gmidi.c driver had a bug in this area; fixed.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
David Brownell
2007-07-01 11:04:54 -07:00
committed by Greg Kroah-Hartman
parent ad8c623f4f
commit 9d8bab58b7
5 changed files with 11 additions and 70 deletions
Download Patch File Download Diff File Expand all files Collapse all files

41
include/linux/usb_gadget.h
View File

@@ -234,47 +234,6 @@ usb_ep_free_request (struct usb_ep *ep, struct usb_request *req)
ep->ops->free_request (ep, req);
}
/**
* usb_ep_alloc_buffer - allocate an I/O buffer
* @ep:the endpoint associated with the buffer
* @len:length of the desired buffer
* @dma:pointer to the buffer's DMA address; must be valid
* @gfp_flags:GFP_* flags to use
*
* 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.
*/
static inline void *
usb_ep_alloc_buffer (struct usb_ep *ep, unsigned len, dma_addr_t *dma,
gfp_t gfp_flags)
{
return ep->ops->alloc_buffer (ep, len, dma, gfp_flags);
}
/**
* usb_ep_free_buffer - frees an i/o buffer
* @ep:the endpoint associated with the buffer
* @buf:CPU view address of the buffer
* @dma:the buffer's DMA address
* @len:length of the buffer
*
* reverses the effect of usb_ep_alloc_buffer().
* caller guarantees the buffer will no longer be accessed
*/
static inline void
usb_ep_free_buffer (struct usb_ep *ep, void *buf, dma_addr_t dma, unsigned len)
{
ep->ops->free_buffer (ep, buf, dma, len);
}
/**
* usb_ep_queue - queues (submits) an I/O request to an endpoint.
* @ep:the endpoint associated with the request