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| author | Jack Pham <jackp@codeaurora.org> | 2017-08-01 02:00:56 -0700 |
|---|---|---|
| committer | Felipe Balbi <felipe.balbi@linux.intel.com> | 2017-08-15 14:18:54 +0300 |
| commit | 31fe084ffaaf8abece14f8ca28e5e3b4e2bf97b6 (patch) | |
| tree | 42714e3aa40f6ce62c1e42be22a24de6efe467f1 /drivers/usb/gadget | |
| parent | f8faa3bf5fc988e504766b8d1bb7b3d5fb09f6f8 (diff) | |
| download | linux-stable-31fe084ffaaf8abece14f8ca28e5e3b4e2bf97b6.tar.gz linux-stable-31fe084ffaaf8abece14f8ca28e5e3b4e2bf97b6.tar.bz2 linux-stable-31fe084ffaaf8abece14f8ca28e5e3b4e2bf97b6.zip | |
usb: gadget: core: unmap request from DMA only if previously mapped
In the SG case this is already handled since a non-zero
request->num_mapped_sgs is a clear indicator that dma_map_sg()
had been called. While it would be nice to do the same for the
singly mapped case by simply checking for non-zero request->dma,
it's conceivable that 0 is a valid dma_addr_t handle. Hence add
a flag 'dma_mapped' to struct usb_request and use this to
determine the need to call dma_unmap_single(). Otherwise, if a
request is not DMA mapped then the result of calling
usb_request_unmap_request() would safely be a no-op.
Signed-off-by: Jack Pham <jackp@codeaurora.org>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Diffstat (limited to 'drivers/usb/gadget')
| -rw-r--r-- | drivers/usb/gadget/udc/core.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/usb/gadget/udc/core.c b/drivers/usb/gadget/udc/core.c index e6f04eee95c4..c1cef6a11ecb 100644 --- a/drivers/usb/gadget/udc/core.c +++ b/drivers/usb/gadget/udc/core.c @@ -812,6 +812,8 @@ int usb_gadget_map_request_by_dev(struct device *dev, dev_err(dev, "failed to map buffer\n"); return -EFAULT; } + + req->dma_mapped = 1; } return 0; @@ -836,9 +838,10 @@ void usb_gadget_unmap_request_by_dev(struct device *dev, is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); req->num_mapped_sgs = 0; - } else { + } else if (req->dma_mapped) { dma_unmap_single(dev, req->dma, req->length, is_in ? DMA_TO_DEVICE : DMA_FROM_DEVICE); + req->dma_mapped = 0; } } EXPORT_SYMBOL_GPL(usb_gadget_unmap_request_by_dev); |