In preparation for honoring xhci-v1.0+ td-fragment handling rules break
out the subroutines of prepare_transfer(). Rather than calculating the
number of trbs required and expanding the ring, v1.0+ hosts will
dynamically resize the ring as it discovers td-fragments that end up
straddling a segment boundary.
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/usb/host/xhci-ring.c | 122 ++++++++++++++++++++++++------------------
1 files changed, 70 insertions(+), 52 deletions(-)
diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 27d271e26445..3a9ed6543dfe 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2920,10 +2920,69 @@ static void queue_trb(struct xhci_ring *ring, bool more_trbs_coming,
* FIXME allocate segments if the ring is full.
*/
static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
- u32 ep_state, unsigned int num_trbs, gfp_t mem_flags)
+ unsigned int num_trbs, gfp_t mem_flags)
{
unsigned int num_trbs_needed;
+ while (1) {
+ if (room_on_ring(xhci, ep_ring, num_trbs))
+ break;
+
+ if (ep_ring == xhci->cmd_ring) {
+ xhci_err(xhci, "Do not support expand command ring\n");
+ return -ENOMEM;
+ }
+
+ xhci_dbg_trace(xhci, trace_xhci_dbg_ring_expansion,
+ "ERROR no room on ep ring, try ring expansion");
+ num_trbs_needed = num_trbs - ep_ring->num_trbs_free;
+ if (xhci_ring_expansion(xhci, ep_ring, num_trbs_needed,
+ mem_flags)) {
+ xhci_err(xhci, "Ring expansion failed\n");
+ return -ENOMEM;
+ }
+ }
+
+ if (enqueue_is_link_trb(ep_ring))
+ advance_enq(ep_ring, 0, do_carry_chain(xhci, ep_ring));
+ return 0;
+}
+
+static int prepare_td(struct xhci_ring *ring, struct urb *urb,
+ unsigned int td_index)
+{
+ struct urb_priv *urb_priv;
+ struct xhci_td *td;
+
+ urb_priv = urb->hcpriv;
+ td = urb_priv->td[td_index];
+
+ INIT_LIST_HEAD(&td->td_list);
+ INIT_LIST_HEAD(&td->cancelled_td_list);
+
+ if (td_index == 0) {
+ struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus);
+ int ret = usb_hcd_link_urb_to_ep(hcd, urb);
+
+ if (ret)
+ return ret;
+ }
+
+ td->urb = urb;
+ /* Add this TD to the tail of the endpoint ring's TD list */
+ list_add_tail(&td->td_list, &ring->td_list);
+ td->start_seg = ring->enq.seg;
+ td->first_trb = xhci_ring_enqueue(ring);
+ urb_priv->td[td_index] = td;
+
+ return 0;
+}
+
+static int check_ep_submit_state(struct xhci_hcd *xhci,
+ struct xhci_ep_ctx *ep_ctx)
+{
+ u32 ep_state = le32_to_cpu(ep_ctx->ep_info) & EP_STATE_MASK;
+
/* Make sure the endpoint has been added to xHC schedule */
switch (ep_state) {
case EP_STATE_DISABLED:
@@ -2951,28 +3010,6 @@ static int prepare_ring(struct xhci_hcd *xhci, struct xhci_ring *ep_ring,
*/
return -EINVAL;
}
-
- while (1) {
- if (room_on_ring(xhci, ep_ring, num_trbs))
- break;
-
- if (ep_ring == xhci->cmd_ring) {
- xhci_err(xhci, "Do not support expand command ring\n");
- return -ENOMEM;
- }
-
- xhci_dbg_trace(xhci, trace_xhci_dbg_ring_expansion,
- "ERROR no room on ep ring, try ring expansion");
- num_trbs_needed = num_trbs - ep_ring->num_trbs_free;
- if (xhci_ring_expansion(xhci, ep_ring, num_trbs_needed,
- mem_flags)) {
- xhci_err(xhci, "Ring expansion failed\n");
- return -ENOMEM;
- }
- }
-
- if (enqueue_is_link_trb(ep_ring))
- advance_enq(ep_ring, 0, do_carry_chain(xhci, ep_ring));
return 0;
}
@@ -2986,8 +3023,6 @@ static int prepare_transfer(struct xhci_hcd *xhci,
gfp_t mem_flags)
{
int ret;
- struct urb_priv *urb_priv;
- struct xhci_td *td;
struct xhci_ring *ep_ring;
struct xhci_ep_ctx *ep_ctx = xhci_get_ep_ctx(xhci, xdev->out_ctx, ep_index);
@@ -2998,33 +3033,15 @@ static int prepare_transfer(struct xhci_hcd *xhci,
return -EINVAL;
}
- ret = prepare_ring(xhci, ep_ring,
- le32_to_cpu(ep_ctx->ep_info) & EP_STATE_MASK,
- num_trbs, mem_flags);
+ ret = check_ep_submit_state(xhci, ep_ctx);
if (ret)
return ret;
- urb_priv = urb->hcpriv;
- td = urb_priv->td[td_index];
-
- INIT_LIST_HEAD(&td->td_list);
- INIT_LIST_HEAD(&td->cancelled_td_list);
-
- if (td_index == 0) {
- ret = usb_hcd_link_urb_to_ep(bus_to_hcd(urb->dev->bus), urb);
- if (unlikely(ret))
- return ret;
- }
-
- td->urb = urb;
- /* Add this TD to the tail of the endpoint ring's TD list */
- list_add_tail(&td->td_list, &ep_ring->td_list);
- td->start_seg = ep_ring->enq.seg;
- td->first_trb = xhci_ring_enqueue(ep_ring);
-
- urb_priv->td[td_index] = td;
+ ret = prepare_ring(xhci, ep_ring, num_trbs, mem_flags);
+ if (ret)
+ return ret;
- return 0;
+ return prepare_td(ep_ring, urb, td_index);
}
static unsigned int count_sg_trbs_needed(struct xhci_hcd *xhci, struct urb *urb)
@@ -3872,8 +3889,10 @@ int xhci_queue_isoc_tx_prepare(struct xhci_hcd *xhci, gfp_t mem_flags,
/* Check the ring to guarantee there is enough room for the whole urb.
* Do not insert any td of the urb to the ring if the check failed.
*/
- ret = prepare_ring(xhci, ep_ring, le32_to_cpu(ep_ctx->ep_info) & EP_STATE_MASK,
- num_trbs, mem_flags);
+ ret = check_ep_submit_state(xhci, ep_ctx);
+ if (ret)
+ return ret;
+ ret = prepare_ring(xhci, ep_ring, num_trbs, mem_flags);
if (ret)
return ret;
@@ -3930,8 +3949,7 @@ static int queue_command(struct xhci_hcd *xhci, struct xhci_command *cmd,
if (!command_must_succeed)
reserved_trbs++;
- ret = prepare_ring(xhci, xhci->cmd_ring, EP_STATE_RUNNING,
- reserved_trbs, GFP_ATOMIC);
+ ret = prepare_ring(xhci, xhci->cmd_ring, reserved_trbs, GFP_ATOMIC);
if (ret < 0) {
xhci_err(xhci, "ERR: No room for command on command ring\n");
if (command_must_succeed)
--
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