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path: root/drivers/usb/host/xhci-ring.c
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Diffstat (limited to 'drivers/usb/host/xhci-ring.c')
-rw-r--r--drivers/usb/host/xhci-ring.c75
1 files changed, 29 insertions, 46 deletions
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 4637da6af765..519dc14a8794 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -3127,9 +3127,10 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
struct scatterlist *sg = NULL;
bool more_trbs_coming = true;
bool need_zero_pkt = false;
- unsigned int num_trbs, last_trb_num, i;
+ bool first_trb = true;
+ unsigned int num_trbs;
unsigned int start_cycle, num_sgs = 0;
- unsigned int running_total, block_len, trb_buff_len, full_len;
+ unsigned int enqd_len, block_len, trb_buff_len, full_len;
int ret;
u32 field, length_field, remainder;
u64 addr;
@@ -3138,14 +3139,19 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
if (!ring)
return -EINVAL;
+ full_len = urb->transfer_buffer_length;
/* If we have scatter/gather list, we use it. */
if (urb->num_sgs) {
num_sgs = urb->num_mapped_sgs;
sg = urb->sg;
+ addr = (u64) sg_dma_address(sg);
+ block_len = sg_dma_len(sg);
num_trbs = count_sg_trbs_needed(urb);
- } else
+ } else {
num_trbs = count_trbs_needed(urb);
-
+ addr = (u64) urb->transfer_dma;
+ block_len = full_len;
+ }
ret = prepare_transfer(xhci, xhci->devs[slot_id],
ep_index, urb->stream_id,
num_trbs, urb, 0, mem_flags);
@@ -3154,8 +3160,6 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
urb_priv = urb->hcpriv;
- last_trb_num = num_trbs - 1;
-
/* Deal with URB_ZERO_PACKET - need one more td/trb */
if (urb->transfer_flags & URB_ZERO_PACKET && urb_priv->length > 1)
need_zero_pkt = true;
@@ -3170,40 +3174,20 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
start_trb = &ring->enqueue->generic;
start_cycle = ring->cycle_state;
- full_len = urb->transfer_buffer_length;
- running_total = 0;
- block_len = 0;
-
/* Queue the TRBs, even if they are zero-length */
- for (i = 0; i < num_trbs; i++) {
+ for (enqd_len = 0; enqd_len < full_len; enqd_len += trb_buff_len) {
field = TRB_TYPE(TRB_NORMAL);
- if (block_len == 0) {
- /* A new contiguous block. */
- if (sg) {
- addr = (u64) sg_dma_address(sg);
- block_len = sg_dma_len(sg);
- } else {
- addr = (u64) urb->transfer_dma;
- block_len = full_len;
- }
- /* TRB buffer should not cross 64KB boundaries */
- trb_buff_len = TRB_BUFF_LEN_UP_TO_BOUNDARY(addr);
- trb_buff_len = min_t(unsigned int,
- trb_buff_len,
- block_len);
- } else {
- /* Further through the contiguous block. */
- trb_buff_len = block_len;
- if (trb_buff_len > TRB_MAX_BUFF_SIZE)
- trb_buff_len = TRB_MAX_BUFF_SIZE;
- }
+ /* TRB buffer should not cross 64KB boundaries */
+ trb_buff_len = TRB_BUFF_LEN_UP_TO_BOUNDARY(addr);
+ trb_buff_len = min_t(unsigned int, trb_buff_len, block_len);
- if (running_total + trb_buff_len > full_len)
- trb_buff_len = full_len - running_total;
+ if (enqd_len + trb_buff_len > full_len)
+ trb_buff_len = full_len - enqd_len;
/* Don't change the cycle bit of the first TRB until later */
- if (i == 0) {
+ if (first_trb) {
+ first_trb = false;
if (start_cycle == 0)
field |= TRB_CYCLE;
} else
@@ -3212,7 +3196,7 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
/* Chain all the TRBs together; clear the chain bit in the last
* TRB to indicate it's the last TRB in the chain.
*/
- if (i < last_trb_num) {
+ if (enqd_len + trb_buff_len < full_len) {
field |= TRB_CHAIN;
} else {
field |= TRB_IOC;
@@ -3225,9 +3209,9 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
field |= TRB_ISP;
/* Set the TRB length, TD size, and interrupter fields. */
- remainder = xhci_td_remainder(xhci, running_total,
- trb_buff_len, full_len,
- urb, more_trbs_coming);
+ remainder = xhci_td_remainder(xhci, enqd_len, trb_buff_len,
+ full_len, urb, more_trbs_coming);
+
length_field = TRB_LEN(trb_buff_len) |
TRB_TD_SIZE(remainder) |
TRB_INTR_TARGET(0);
@@ -3238,17 +3222,16 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
length_field,
field);
- running_total += trb_buff_len;
addr += trb_buff_len;
block_len -= trb_buff_len;
- if (sg) {
- if (block_len == 0) {
- /* New sg entry */
- --num_sgs;
- if (num_sgs == 0)
- break;
+ if (sg && block_len == 0) {
+ /* New sg entry */
+ --num_sgs;
+ if (num_sgs != 0) {
sg = sg_next(sg);
+ block_len = sg_dma_len(sg);
+ addr = (u64) sg_dma_address(sg);
}
}
}
@@ -3262,7 +3245,7 @@ int xhci_queue_bulk_tx(struct xhci_hcd *xhci, gfp_t mem_flags,
queue_trb(xhci, ring, 0, 0, 0, TRB_INTR_TARGET(0), field);
}
- check_trb_math(urb, running_total);
+ check_trb_math(urb, enqd_len);
giveback_first_trb(xhci, slot_id, ep_index, urb->stream_id,
start_cycle, start_trb);
return 0;