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authorMing Lei <tom.leiming@gmail.com>2010-09-30 08:32:44 -0400
committerGreg Kroah-Hartman <gregkh@suse.de>2010-10-22 13:22:00 -0400
commit689d6eacd1b7c3677bfe6ee367766f21c3c80e26 (patch)
tree2524c96c3e6dbd6244292a2a4d0ba769564d5ecf /drivers/usb/host
parent00be545e49d83485d49a598d3b7e090088934be8 (diff)
USB: UHCI: add native scatter-gather support(v1)
This patch adds native scatter-gather support to uhci-hcd. Reviewed-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Ming Lei <tom.leiming@gmail.com> Acked-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/host')
-rw-r--r--drivers/usb/host/uhci-q.c33
1 files changed, 29 insertions, 4 deletions
diff --git a/drivers/usb/host/uhci-q.c b/drivers/usb/host/uhci-q.c
index d3ade4018487..2090b45eb606 100644
--- a/drivers/usb/host/uhci-q.c
+++ b/drivers/usb/host/uhci-q.c
@@ -917,10 +917,13 @@ static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb,
917 unsigned long destination, status; 917 unsigned long destination, status;
918 int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize); 918 int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize);
919 int len = urb->transfer_buffer_length; 919 int len = urb->transfer_buffer_length;
920 dma_addr_t data = urb->transfer_dma; 920 int this_sg_len;
921 dma_addr_t data;
921 __le32 *plink; 922 __le32 *plink;
922 struct urb_priv *urbp = urb->hcpriv; 923 struct urb_priv *urbp = urb->hcpriv;
923 unsigned int toggle; 924 unsigned int toggle;
925 struct scatterlist *sg;
926 int i;
924 927
925 if (len < 0) 928 if (len < 0)
926 return -EINVAL; 929 return -EINVAL;
@@ -937,12 +940,26 @@ static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb,
937 if (usb_pipein(urb->pipe)) 940 if (usb_pipein(urb->pipe))
938 status |= TD_CTRL_SPD; 941 status |= TD_CTRL_SPD;
939 942
943 i = urb->num_sgs;
944 if (len > 0 && i > 0) {
945 sg = urb->sg;
946 data = sg_dma_address(sg);
947
948 /* urb->transfer_buffer_length may be smaller than the
949 * size of the scatterlist (or vice versa)
950 */
951 this_sg_len = min_t(int, sg_dma_len(sg), len);
952 } else {
953 sg = NULL;
954 data = urb->transfer_dma;
955 this_sg_len = len;
956 }
940 /* 957 /*
941 * Build the DATA TDs 958 * Build the DATA TDs
942 */ 959 */
943 plink = NULL; 960 plink = NULL;
944 td = qh->dummy_td; 961 td = qh->dummy_td;
945 do { /* Allow zero length packets */ 962 for (;;) { /* Allow zero length packets */
946 int pktsze = maxsze; 963 int pktsze = maxsze;
947 964
948 if (len <= pktsze) { /* The last packet */ 965 if (len <= pktsze) { /* The last packet */
@@ -965,10 +982,18 @@ static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb,
965 plink = &td->link; 982 plink = &td->link;
966 status |= TD_CTRL_ACTIVE; 983 status |= TD_CTRL_ACTIVE;
967 984
985 toggle ^= 1;
968 data += pktsze; 986 data += pktsze;
987 this_sg_len -= pktsze;
969 len -= maxsze; 988 len -= maxsze;
970 toggle ^= 1; 989 if (this_sg_len <= 0) {
971 } while (len > 0); 990 if (--i <= 0 || len <= 0)
991 break;
992 sg = sg_next(sg);
993 data = sg_dma_address(sg);
994 this_sg_len = min_t(int, sg_dma_len(sg), len);
995 }
996 }
972 997
973 /* 998 /*
974 * URB_ZERO_PACKET means adding a 0-length packet, if direction 999 * URB_ZERO_PACKET means adding a 0-length packet, if direction