usb: dwc3: gadget: retire LST bit completely

The only endpoint which actually requires LST bit
and XferComplete is ep0/1. Let's save some time by
completely removing LST bit support and
XferComplete.

This simplifies and consolidates endpoint handling
for all other 3 transfer types while also avoiding
extra interrupts.

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 1f5597e..15df5ed 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -490,7 +490,8 @@ static int dwc3_gadget_set_ep_config(struct dwc3 *dwc, struct dwc3_ep *dep,
                params.param0 |= DWC3_DEPCFG_ACTION_INIT;
        }
 
-       params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN;
+       if (usb_endpoint_xfer_control(desc))
+               params.param1 = DWC3_DEPCFG_XFER_COMPLETE_EN;
 
        if (dep->number <= 1 || usb_endpoint_xfer_isoc(desc))
                params.param1 |= DWC3_DEPCFG_XFER_NOT_READY_EN;
@@ -771,15 +772,13 @@ static void dwc3_gadget_ep_free_request(struct usb_ep *ep,
  */
 static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
                struct dwc3_request *req, dma_addr_t dma,
-               unsigned length, unsigned last, unsigned chain, unsigned node)
+               unsigned length, unsigned chain, unsigned node)
 {
        struct dwc3_trb         *trb;
 
-       dwc3_trace(trace_dwc3_gadget, "%s: req %p dma %08llx length %d%s%s",
+       dwc3_trace(trace_dwc3_gadget, "%s: req %p dma %08llx length %d%s",
                        dep->name, req, (unsigned long long) dma,
-                       length, last ? " last" : "",
-                       chain ? " chain" : "");
-
+                       length, chain ? " chain" : "");
 
        trb = &dep->trb_pool[dep->trb_enqueue];
 
@@ -829,9 +828,6 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
        if (!req->request.no_interrupt && !chain)
                trb->ctrl |= DWC3_TRB_CTRL_IOC | DWC3_TRB_CTRL_ISP_IMI;
 
-       if (last && !usb_endpoint_xfer_isoc(dep->endpoint.desc))
-               trb->ctrl |= DWC3_TRB_CTRL_LST;
-
        if (chain)
                trb->ctrl |= DWC3_TRB_CTRL_CHN;
 
@@ -894,13 +890,11 @@ static u32 dwc3_calc_trbs_left(struct dwc3_ep *dep)
 }
 
 static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
-               struct dwc3_request *req, unsigned int trbs_left,
-               unsigned int more_coming)
+               struct dwc3_request *req, unsigned int trbs_left)
 {
        struct usb_request *request = &req->request;
        struct scatterlist *sg = request->sg;
        struct scatterlist *s;
-       unsigned int    last = false;
        unsigned int    length;
        dma_addr_t      dma;
        int             i;
@@ -911,48 +905,28 @@ static void dwc3_prepare_one_trb_sg(struct dwc3_ep *dep,
                length = sg_dma_len(s);
                dma = sg_dma_address(s);
 
-               if (sg_is_last(s)) {
-                       if (usb_endpoint_xfer_int(dep->endpoint.desc) ||
-                               !more_coming)
-                               last = true;
-
-                       chain = false;
-               }
-
-               if (!trbs_left--)
-                       last = true;
-
-               if (last)
+               if (sg_is_last(s))
                        chain = false;
 
                dwc3_prepare_one_trb(dep, req, dma, length,
-                               last, chain, i);
+                               chain, i);
 
-               if (last)
+               if (!trbs_left--)
                        break;
        }
 }
 
 static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
-               struct dwc3_request *req, unsigned int trbs_left,
-               unsigned int more_coming)
+               struct dwc3_request *req, unsigned int trbs_left)
 {
-       unsigned int    last = false;
        unsigned int    length;
        dma_addr_t      dma;
 
        dma = req->request.dma;
        length = req->request.length;
 
-       if (!trbs_left)
-               last = true;
-
-       /* Is this the last request? */
-       if (usb_endpoint_xfer_int(dep->endpoint.desc) || !more_coming)
-               last = true;
-
        dwc3_prepare_one_trb(dep, req, dma, length,
-                       last, false, 0);
+                       false, 0);
 }
 
 /*
@@ -966,7 +940,6 @@ static void dwc3_prepare_one_trb_linear(struct dwc3_ep *dep,
 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);
@@ -975,15 +948,11 @@ static void dwc3_prepare_trbs(struct dwc3_ep *dep)
        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--,
-                                       more_coming);
+                       dwc3_prepare_one_trb_sg(dep, req, trbs_left--);
                else
-                       dwc3_prepare_one_trb_linear(dep, req, trbs_left--,
-                                       more_coming);
+                       dwc3_prepare_one_trb_linear(dep, req, trbs_left--);
 
                if (!trbs_left)
                        return;
@@ -1127,8 +1096,7 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req)
         * This will save one IRQ (XFER_NOT_READY) and possibly make it a
         * little bit faster.
         */
-       if (!usb_endpoint_xfer_isoc(dep->endpoint.desc) &&
-                       !usb_endpoint_xfer_int(dep->endpoint.desc)) {
+       if (!usb_endpoint_xfer_isoc(dep->endpoint.desc)) {
                ret = __dwc3_gadget_kick_transfer(dep, 0);
                goto out;
        }
@@ -2045,7 +2013,7 @@ static int dwc3_cleanup_done_reqs(struct dwc3 *dwc, struct dwc3_ep *dep,
                int chain;
 
                req = next_request(&dep->started_list);
-               if (WARN_ON_ONCE(!req))
+               if (!req)
                        return 1;
 
                chain = req->request.num_mapped_sgs > 0;