usb: dwc3: ep0: explicitly call dwc3_ep0_prepare_one_trb()

Let's call dwc3_ep0_prepare_one_trb() explicitly
because there are occasions where we will need more
than one TRB to handle an EP0 transfer.

A follow-up patch will fix one bug related to
multiple-TRB Data Phases when it comes to
mapping/unmapping requests for DMA.

Cc: <stable@vger.kernel.org>
Reported-by: Janusz Dziedzic <januszx.dziedzic@linux.intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 06febd0..9bb1f85 100644 (file)
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -69,8 +69,7 @@ static void dwc3_ep0_prepare_one_trb(struct dwc3 *dwc, u8 epnum,
        trace_dwc3_prepare_trb(dep, trb);
 }
 
-static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
-               u32 len, u32 type, bool chain)
+static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum)
 {
        struct dwc3_gadget_ep_cmd_params params;
        struct dwc3_ep                  *dep;
@@ -80,8 +79,6 @@ static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
        if (dep->flags & DWC3_EP_BUSY)
                return 0;
 
-       dwc3_ep0_prepare_one_trb(dwc, epnum, buf_dma, len, type, chain);
-
        memset(&params, 0, sizeof(params));
        params.param0 = upper_32_bits(dwc->ep0_trb_addr);
        params.param1 = lower_32_bits(dwc->ep0_trb_addr);
@@ -286,8 +283,9 @@ void dwc3_ep0_out_start(struct dwc3 *dwc)
 
        complete(&dwc->ep0_in_setup);
 
-       ret = dwc3_ep0_start_trans(dwc, 0, dwc->ctrl_req_addr, 8,
+       dwc3_ep0_prepare_one_trb(dwc, 0, dwc->ctrl_req_addr, 8,
                        DWC3_TRBCTL_CONTROL_SETUP, false);
+       ret = dwc3_ep0_start_trans(dwc, 0);
        WARN_ON(ret < 0);
 }
 
@@ -918,9 +916,9 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc,
 
                        dwc->ep0_next_event = DWC3_EP0_COMPLETE;
 
-                       ret = dwc3_ep0_start_trans(dwc, epnum,
-                                       dwc->ctrl_req_addr, 0,
-                                       DWC3_TRBCTL_CONTROL_DATA, false);
+                       dwc3_ep0_prepare_one_trb(dwc, epnum, dwc->ctrl_req_addr,
+                                       0, DWC3_TRBCTL_CONTROL_DATA, false);
+                       ret = dwc3_ep0_start_trans(dwc, epnum);
                        WARN_ON(ret < 0);
                }
        }
@@ -999,9 +997,10 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
        req->direction = !!dep->number;
 
        if (req->request.length == 0) {
-               ret = dwc3_ep0_start_trans(dwc, dep->number,
+               dwc3_ep0_prepare_one_trb(dwc, dep->number,
                                dwc->ctrl_req_addr, 0,
                                DWC3_TRBCTL_CONTROL_DATA, false);
+               ret = dwc3_ep0_start_trans(dwc, dep->number);
        } else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
                        && (dep->number == 0)) {
                u32     transfer_size = 0;
@@ -1017,7 +1016,7 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
                if (req->request.length > DWC3_EP0_BOUNCE_SIZE) {
                        transfer_size = ALIGN(req->request.length - maxpacket,
                                              maxpacket);
-                       ret = dwc3_ep0_start_trans(dwc, dep->number,
+                       dwc3_ep0_prepare_one_trb(dwc, dep->number,
                                                   req->request.dma,
                                                   transfer_size,
                                                   DWC3_TRBCTL_CONTROL_DATA,
@@ -1029,18 +1028,20 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
 
                dwc->ep0_bounced = true;
 
-               ret = dwc3_ep0_start_trans(dwc, dep->number,
+               dwc3_ep0_prepare_one_trb(dwc, dep->number,
                                dwc->ep0_bounce_addr, transfer_size,
                                DWC3_TRBCTL_CONTROL_DATA, false);
+               ret = dwc3_ep0_start_trans(dwc, dep->number);
        } else {
                ret = usb_gadget_map_request_by_dev(dwc->sysdev,
                                &req->request, dep->number);
                if (ret)
                        return;
 
-               ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma,
+               dwc3_ep0_prepare_one_trb(dwc, dep->number, req->request.dma,
                                req->request.length, DWC3_TRBCTL_CONTROL_DATA,
                                false);
+               ret = dwc3_ep0_start_trans(dwc, dep->number);
        }
 
        WARN_ON(ret < 0);
@@ -1054,8 +1055,9 @@ static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
        type = dwc->three_stage_setup ? DWC3_TRBCTL_CONTROL_STATUS3
                : DWC3_TRBCTL_CONTROL_STATUS2;
 
-       return dwc3_ep0_start_trans(dwc, dep->number,
+       dwc3_ep0_prepare_one_trb(dwc, dep->number,
                        dwc->ctrl_req_addr, 0, type, false);
+       return dwc3_ep0_start_trans(dwc, dep->number);
 }
 
 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)