usb: dwc3: gadget: Cleanup SG handling

The current logic in dwc3 driver is tracking req->num_queued_sgs and
req->sg. But they can be checked base on the num_pending_sgs and
num_trbs. They are redundant and can complicate the SG logic. Let's
remove them.

Signed-off-by: Thinh Nguyen <[email protected]>
Link: https://lore.kernel.org/r/96c7bf8f6b3e91e607d5b78ea51cb1d00c614eaf.1731545781.git.Thinh.Nguyen@synopsys.com
Signed-off-by: Greg Kroah-Hartman <[email protected]>

diff --git a/drivers/usb/dwc3/core.h b/drivers/usb/dwc3/core.h
index 2dccd8fa7efdd840ca800f4e5228269d9c5e2386..aa09ccbf34a5895cc14f2542da3e1ae874c94bac 100644 (file)
--- a/drivers/usb/dwc3/core.h
+++ b/drivers/usb/dwc3/core.h
@@ -941,10 +941,8 @@ struct dwc3_hwparams {
  * @request: struct usb_request to be transferred
  * @list: a list_head used for request queueing
  * @dep: struct dwc3_ep owning this request
- * @sg: pointer to first incomplete sg
  * @start_sg: pointer to the sg which should be queued next
  * @num_pending_sgs: counter to pending sgs
- * @num_queued_sgs: counter to the number of sgs which already got queued
  * @remaining: amount of data remaining
  * @status: internal dwc3 request status tracking
  * @epnum: endpoint number to which this request refers
@@ -964,7 +962,6 @@ struct dwc3_request {
        struct scatterlist      *start_sg;
 
        unsigned int            num_pending_sgs;
-       unsigned int            num_queued_sgs;
        unsigned int            remaining;
 
        unsigned int            status;

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 3a5a0d8be33c049736966c5b947b9cbbc777af7f..687bb8cc4114861fd06a6c1cafd582e5f6e85cbd 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -1544,7 +1544,6 @@ static int dwc3_prepare_trbs_sg(struct dwc3_ep *dep,
                if (!last_sg)
                        req->start_sg = sg_next(s);
 
-               req->num_queued_sgs++;
                req->num_pending_sgs--;
 
                /*
@@ -1625,9 +1624,7 @@ static int dwc3_prepare_trbs(struct dwc3_ep *dep)
                if (ret)
                        return ret;
 
-               req->sg                 = req->request.sg;
-               req->start_sg           = req->sg;
-               req->num_queued_sgs     = 0;
+               req->start_sg           = req->request.sg;
                req->num_pending_sgs    = req->request.num_mapped_sgs;
 
                if (req->num_pending_sgs > 0) {
@@ -3472,20 +3469,16 @@ static int dwc3_gadget_ep_reclaim_trb_sg(struct dwc3_ep *dep,
                int status)
 {
        struct dwc3_trb *trb;
-       struct scatterlist *sg = req->sg;
-       struct scatterlist *s;
-       unsigned int num_queued = req->num_queued_sgs;
+       unsigned int num_completed_trbs = req->num_trbs;
        unsigned int i;
        int ret = 0;
 
-       for_each_sg(sg, s, num_queued, i) {
+       for (i = 0; i < num_completed_trbs; i++) {
                trb = &dep->trb_pool[dep->trb_dequeue];
 
-               req->sg = sg_next(s);
-               req->num_queued_sgs--;
-
                ret = dwc3_gadget_ep_reclaim_completed_trb(dep, req,
-                               trb, event, status, true);
+                               trb, event, status,
+                               !!(trb->ctrl & DWC3_TRB_CTRL_CHN));
                if (ret)
                        break;
        }
@@ -3493,19 +3486,9 @@ static int dwc3_gadget_ep_reclaim_trb_sg(struct dwc3_ep *dep,
        return ret;
 }
 
-static int dwc3_gadget_ep_reclaim_trb_linear(struct dwc3_ep *dep,
-               struct dwc3_request *req, const struct dwc3_event_depevt *event,
-               int status)
-{
-       struct dwc3_trb *trb = &dep->trb_pool[dep->trb_dequeue];
-
-       return dwc3_gadget_ep_reclaim_completed_trb(dep, req, trb,
-                       event, status, false);
-}
-
 static bool dwc3_gadget_ep_request_completed(struct dwc3_request *req)
 {
-       return req->num_pending_sgs == 0 && req->num_queued_sgs == 0;
+       return req->num_pending_sgs == 0 && req->num_trbs == 0;
 }
 
 static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
@@ -3515,24 +3498,13 @@ static int dwc3_gadget_ep_cleanup_completed_request(struct dwc3_ep *dep,
        int request_status;
        int ret;
 
-       if (req->request.num_mapped_sgs)
-               ret = dwc3_gadget_ep_reclaim_trb_sg(dep, req, event,
-                               status);
-       else
-               ret = dwc3_gadget_ep_reclaim_trb_linear(dep, req, event,
-                               status);
+       ret = dwc3_gadget_ep_reclaim_trb_sg(dep, req, event, status);
 
        req->request.actual = req->request.length - req->remaining;
 
        if (!dwc3_gadget_ep_request_completed(req))
                goto out;
 
-       if (req->needs_extra_trb) {
-               ret = dwc3_gadget_ep_reclaim_trb_linear(dep, req, event,
-                               status);
-               req->needs_extra_trb = false;
-       }
-
        /*
         * The event status only reflects the status of the TRB with IOC set.
         * For the requests that don't set interrupt on completion, the driver