[PATCH 5/6] usb: remove commented out dma wrappers

From: Christoph Hellwig
Date: Tue Sep 03 2019 - 04:46:40 EST


These wrappers have never seen use and have been commented out
for a long time. Remove them for good.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
drivers/usb/core/usb.c | 222 -----------------------------------------
1 file changed, 222 deletions(-)

diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c
index 0ab8738047da..f16c26dc079d 100644
--- a/drivers/usb/core/usb.c
+++ b/drivers/usb/core/usb.c
@@ -933,228 +933,6 @@ void usb_free_coherent(struct usb_device *dev, size_t size, void *addr,
}
EXPORT_SYMBOL_GPL(usb_free_coherent);

-/**
- * usb_buffer_map - create DMA mapping(s) for an urb
- * @urb: urb whose transfer_buffer/setup_packet will be mapped
- *
- * URB_NO_TRANSFER_DMA_MAP is added to urb->transfer_flags if the operation
- * succeeds. If the device is connected to this system through a non-DMA
- * controller, this operation always succeeds.
- *
- * This call would normally be used for an urb which is reused, perhaps
- * as the target of a large periodic transfer, with usb_buffer_dmasync()
- * calls to synchronize memory and dma state.
- *
- * Reverse the effect of this call with usb_buffer_unmap().
- *
- * Return: Either %NULL (indicating no buffer could be mapped), or @urb.
- *
- */
-#if 0
-struct urb *usb_buffer_map(struct urb *urb)
-{
- struct usb_bus *bus;
- struct device *controller;
-
- if (!urb
- || !urb->dev
- || !(bus = urb->dev->bus)
- || !(controller = bus->sysdev))
- return NULL;
-
- if (controller->dma_mask) {
- urb->transfer_dma = dma_map_single(controller,
- urb->transfer_buffer, urb->transfer_buffer_length,
- usb_pipein(urb->pipe)
- ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
- /* FIXME generic api broken like pci, can't report errors */
- /* if (urb->transfer_dma == DMA_ADDR_INVALID) return 0; */
- } else
- urb->transfer_dma = ~0;
- urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
- return urb;
-}
-EXPORT_SYMBOL_GPL(usb_buffer_map);
-#endif /* 0 */
-
-/* XXX DISABLED, no users currently. If you wish to re-enable this
- * XXX please determine whether the sync is to transfer ownership of
- * XXX the buffer from device to cpu or vice verse, and thusly use the
- * XXX appropriate _for_{cpu,device}() method. -DaveM
- */
-#if 0
-
-/**
- * usb_buffer_dmasync - synchronize DMA and CPU view of buffer(s)
- * @urb: urb whose transfer_buffer/setup_packet will be synchronized
- */
-void usb_buffer_dmasync(struct urb *urb)
-{
- struct usb_bus *bus;
- struct device *controller;
-
- if (!urb
- || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
- || !urb->dev
- || !(bus = urb->dev->bus)
- || !(controller = bus->sysdev))
- return;
-
- if (controller->dma_mask) {
- dma_sync_single_for_cpu(controller,
- urb->transfer_dma, urb->transfer_buffer_length,
- usb_pipein(urb->pipe)
- ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
- if (usb_pipecontrol(urb->pipe))
- dma_sync_single_for_cpu(controller,
- urb->setup_dma,
- sizeof(struct usb_ctrlrequest),
- DMA_TO_DEVICE);
- }
-}
-EXPORT_SYMBOL_GPL(usb_buffer_dmasync);
-#endif
-
-/**
- * usb_buffer_unmap - free DMA mapping(s) for an urb
- * @urb: urb whose transfer_buffer will be unmapped
- *
- * Reverses the effect of usb_buffer_map().
- */
-#if 0
-void usb_buffer_unmap(struct urb *urb)
-{
- struct usb_bus *bus;
- struct device *controller;
-
- if (!urb
- || !(urb->transfer_flags & URB_NO_TRANSFER_DMA_MAP)
- || !urb->dev
- || !(bus = urb->dev->bus)
- || !(controller = bus->sysdev))
- return;
-
- if (controller->dma_mask) {
- dma_unmap_single(controller,
- urb->transfer_dma, urb->transfer_buffer_length,
- usb_pipein(urb->pipe)
- ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
- }
- urb->transfer_flags &= ~URB_NO_TRANSFER_DMA_MAP;
-}
-EXPORT_SYMBOL_GPL(usb_buffer_unmap);
-#endif /* 0 */
-
-#if 0
-/**
- * usb_buffer_map_sg - create scatterlist DMA mapping(s) for an endpoint
- * @dev: device to which the scatterlist will be mapped
- * @is_in: mapping transfer direction
- * @sg: the scatterlist to map
- * @nents: the number of entries in the scatterlist
- *
- * Return: Either < 0 (indicating no buffers could be mapped), or the
- * number of DMA mapping array entries in the scatterlist.
- *
- * Note:
- * The caller is responsible for placing the resulting DMA addresses from
- * the scatterlist into URB transfer buffer pointers, and for setting the
- * URB_NO_TRANSFER_DMA_MAP transfer flag in each of those URBs.
- *
- * Top I/O rates come from queuing URBs, instead of waiting for each one
- * to complete before starting the next I/O. This is particularly easy
- * to do with scatterlists. Just allocate and submit one URB for each DMA
- * mapping entry returned, stopping on the first error or when all succeed.
- * Better yet, use the usb_sg_*() calls, which do that (and more) for you.
- *
- * This call would normally be used when translating scatterlist requests,
- * rather than usb_buffer_map(), since on some hardware (with IOMMUs) it
- * may be able to coalesce mappings for improved I/O efficiency.
- *
- * Reverse the effect of this call with usb_buffer_unmap_sg().
- */
-int usb_buffer_map_sg(const struct usb_device *dev, int is_in,
- struct scatterlist *sg, int nents)
-{
- struct usb_bus *bus;
- struct device *controller;
-
- if (!dev
- || !(bus = dev->bus)
- || !(controller = bus->sysdev)
- || !controller->dma_mask)
- return -EINVAL;
-
- /* FIXME generic api broken like pci, can't report errors */
- return dma_map_sg(controller, sg, nents,
- is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE) ? : -ENOMEM;
-}
-EXPORT_SYMBOL_GPL(usb_buffer_map_sg);
-#endif
-
-/* XXX DISABLED, no users currently. If you wish to re-enable this
- * XXX please determine whether the sync is to transfer ownership of
- * XXX the buffer from device to cpu or vice verse, and thusly use the
- * XXX appropriate _for_{cpu,device}() method. -DaveM
- */
-#if 0
-
-/**
- * usb_buffer_dmasync_sg - synchronize DMA and CPU view of scatterlist buffer(s)
- * @dev: device to which the scatterlist will be mapped
- * @is_in: mapping transfer direction
- * @sg: the scatterlist to synchronize
- * @n_hw_ents: the positive return value from usb_buffer_map_sg
- *
- * Use this when you are re-using a scatterlist's data buffers for
- * another USB request.
- */
-void usb_buffer_dmasync_sg(const struct usb_device *dev, int is_in,
- struct scatterlist *sg, int n_hw_ents)
-{
- struct usb_bus *bus;
- struct device *controller;
-
- if (!dev
- || !(bus = dev->bus)
- || !(controller = bus->sysdev)
- || !controller->dma_mask)
- return;
-
- dma_sync_sg_for_cpu(controller, sg, n_hw_ents,
- is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
-}
-EXPORT_SYMBOL_GPL(usb_buffer_dmasync_sg);
-#endif
-
-#if 0
-/**
- * usb_buffer_unmap_sg - free DMA mapping(s) for a scatterlist
- * @dev: device to which the scatterlist will be mapped
- * @is_in: mapping transfer direction
- * @sg: the scatterlist to unmap
- * @n_hw_ents: the positive return value from usb_buffer_map_sg
- *
- * Reverses the effect of usb_buffer_map_sg().
- */
-void usb_buffer_unmap_sg(const struct usb_device *dev, int is_in,
- struct scatterlist *sg, int n_hw_ents)
-{
- struct usb_bus *bus;
- struct device *controller;
-
- if (!dev
- || !(bus = dev->bus)
- || !(controller = bus->sysdev)
- || !controller->dma_mask)
- return;
-
- dma_unmap_sg(controller, sg, n_hw_ents,
- is_in ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
-}
-EXPORT_SYMBOL_GPL(usb_buffer_unmap_sg);
-#endif
-
/*
* Notifications of device and interface registration
*/
--
2.20.1