diff options
-rw-r--r-- | drivers/usb/host/xhci-ring.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c index d42a738cdaa7..02d81985c454 100644 --- a/drivers/usb/host/xhci-ring.c +++ b/drivers/usb/host/xhci-ring.c @@ -74,16 +74,15 @@ dma_addr_t xhci_trb_virt_to_dma(struct xhci_segment *seg, union xhci_trb *trb) { - dma_addr_t offset; + unsigned long segment_offset; - if (!seg || !trb || (void *) trb < (void *) seg->trbs) + if (!seg || !trb || trb < seg->trbs) return 0; - /* offset in bytes, since these are byte-addressable */ - offset = trb - seg->trbs; - /* SEGMENT_SIZE in bytes, trbs are 16-byte aligned */ - if (offset > SEGMENT_SIZE || (offset % sizeof(*trb)) != 0) + /* offset in TRBs */ + segment_offset = trb - seg->trbs; + if (segment_offset > TRBS_PER_SEGMENT) return 0; - return seg->dma + offset; + return seg->dma + (segment_offset * sizeof(*trb)); } /* Does this link TRB point to the first segment in a ring, |