usb: dwc3: gadget: use allocated/queued reqs for LST bit
Let's only set LST bit when we run out of space in
our TRB ring. For all other cases, we keep LST bit
unset which will prevent constant allocation and
deallocation of endpoint transfer resources.
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index a7c2548..eea4127 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -897,7 +897,8 @@
}
static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
- struct dwc3_request *req, unsigned int trbs_left)
+ struct dwc3_request *req, unsigned int trbs_left,
+ unsigned int more_coming)
{
struct usb_request *request = &req->request;
struct scatterlist *sg = request->sg;
@@ -914,7 +915,8 @@
dma = sg_dma_address(s);
if (sg_is_last(s)) {
- if (list_is_last(&req->list, &dep->pending_list))
+ if (usb_endpoint_xfer_int(dep->endpoint.desc) ||
+ !more_coming)
last = true;
chain = false;
@@ -935,7 +937,8 @@
}
static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
- struct dwc3_request *req, unsigned int trbs_left)
+ struct dwc3_request *req, unsigned int trbs_left,
+ unsigned int more_coming)
{
unsigned int last = false;
unsigned int length;
@@ -948,7 +951,7 @@
last = true;
/* Is this the last request? */
- if (list_is_last(&req->list, &dep->pending_list))
+ if (usb_endpoint_xfer_int(dep->endpoint.desc) || !more_coming)
last = true;
dwc3_prepare_one_trb(dep, req, dma, length,
@@ -966,6 +969,7 @@
static void dwc3_prepare_trbs(struct dwc3_ep *dep)
{
struct dwc3_request *req, *n;
+ unsigned int more_coming;
u32 trbs_left;
BUILD_BUG_ON_NOT_POWER_OF_2(DWC3_TRB_NUM);
@@ -974,11 +978,15 @@
if (!trbs_left)
return;
+ more_coming = dep->allocated_requests - dep->queued_requests;
+
list_for_each_entry_safe(req, n, &dep->pending_list, list) {
if (req->request.num_mapped_sgs > 0)
- dwc3_prepare_one_trb_sg(dep, req, trbs_left--);
+ dwc3_prepare_one_trb_sg(dep, req, trbs_left--,
+ more_coming);
else
- dwc3_prepare_one_trb_linear(dep, req, trbs_left--);
+ dwc3_prepare_one_trb_linear(dep, req, trbs_left--,
+ more_coming);
if (!trbs_left)
return;