usb: dwc3: Add chained TRB support for ep0

dwc3 can do only max packet aligned transfers. So in case request length
is not max packet aligned and is bigger than DWC3_EP0_BOUNCE_SIZE
two chained TRBs is required to handle the transfer.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index fce2558df2a0cc9035261d7072563c1caabd9840..aba614fb4e984011db4b24f09bd3404ded5770fb 100644 (file)
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -48,7 +48,7 @@ static const char *dwc3_ep0_state_string(enum dwc3_ep0_state state)
 }
 
 static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
-               u32 len, u32 type)
+                               u32 len, u32 type, unsigned chain)
 {
        struct dwc3_gadget_ep_cmd_params params;
        struct dwc3_trb                 *trb;
@@ -62,7 +62,10 @@ static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
                return 0;
        }
 
-       trb = dwc->ep0_trb;
+       trb = &dwc->ep0_trb[dep->free_slot];
+
+       if (chain)
+               dep->free_slot++;
 
        trb->bpl = lower_32_bits(buf_dma);
        trb->bph = upper_32_bits(buf_dma);
@@ -70,13 +73,20 @@ static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
        trb->ctrl = type;
 
        trb->ctrl |= (DWC3_TRB_CTRL_HWO
-                       | DWC3_TRB_CTRL_LST
-                       | DWC3_TRB_CTRL_IOC
                        | DWC3_TRB_CTRL_ISP_IMI);
 
+       if (chain)
+               trb->ctrl |= DWC3_TRB_CTRL_CHN;
+       else
+               trb->ctrl |= (DWC3_TRB_CTRL_IOC
+                               | DWC3_TRB_CTRL_LST);
+
        dwc3_flush_cache((int)buf_dma, len);
        dwc3_flush_cache((int)trb, sizeof(*trb));
 
+       if (chain)
+               return 0;
+
        memset(&params, 0, sizeof(params));
        params.param0 = upper_32_bits(dwc->ep0_trb_addr);
        params.param1 = lower_32_bits(dwc->ep0_trb_addr);
@@ -289,7 +299,7 @@ void dwc3_ep0_out_start(struct dwc3 *dwc)
        int                             ret;
 
        ret = dwc3_ep0_start_trans(dwc, 0, dwc->ctrl_req_addr, 8,
-                       DWC3_TRBCTL_CONTROL_SETUP);
+                                  DWC3_TRBCTL_CONTROL_SETUP, 0);
        WARN_ON(ret < 0);
 }
 
@@ -800,6 +810,23 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc,
        maxp = ep0->endpoint.maxpacket;
 
        if (dwc->ep0_bounced) {
+               /*
+                * Handle the first TRB before handling the bounce buffer if
+                * the request length is greater than the bounce buffer size.
+                */
+               if (ur->length > DWC3_EP0_BOUNCE_SIZE) {
+                       transfer_size = (ur->length / maxp) * maxp;
+                       transferred = transfer_size - length;
+                       buf = (u8 *)buf + transferred;
+                       ur->actual += transferred;
+
+                       trb++;
+                       dwc3_flush_cache((int)trb, sizeof(*trb));
+                       length = trb->size & DWC3_TRB_SIZE_MASK;
+
+                       ep0->free_slot = 0;
+               }
+
                transfer_size = roundup((ur->length - transfer_size),
                                        maxp);
                transferred = min_t(u32, ur->length - transferred,
@@ -827,7 +854,7 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc,
 
                        ret = dwc3_ep0_start_trans(dwc, epnum,
                                        dwc->ctrl_req_addr, 0,
-                                       DWC3_TRBCTL_CONTROL_DATA);
+                                       DWC3_TRBCTL_CONTROL_DATA, 0);
                        WARN_ON(ret < 0);
                }
        }
@@ -908,11 +935,11 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
 
        if (req->request.length == 0) {
                ret = dwc3_ep0_start_trans(dwc, dep->number,
-                               dwc->ctrl_req_addr, 0,
-                               DWC3_TRBCTL_CONTROL_DATA);
-       } else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket)
-                       && (dep->number == 0)) {
-               u32     transfer_size;
+                                          dwc->ctrl_req_addr, 0,
+                                          DWC3_TRBCTL_CONTROL_DATA, 0);
+       } else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket) &&
+                       (dep->number == 0)) {
+               u32     transfer_size = 0;
                u32     maxpacket;
 
                ret = usb_gadget_map_request(&dwc->gadget, &req->request,
@@ -922,10 +949,18 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
                        return;
                }
 
-               WARN_ON(req->request.length > DWC3_EP0_BOUNCE_SIZE);
-
                maxpacket = dep->endpoint.maxpacket;
-               transfer_size = roundup(req->request.length, maxpacket);
+               if (req->request.length > DWC3_EP0_BOUNCE_SIZE) {
+                       transfer_size = (req->request.length / maxpacket) *
+                                               maxpacket;
+                       ret = dwc3_ep0_start_trans(dwc, dep->number,
+                                                  req->request.dma,
+                                                  transfer_size,
+                                                  DWC3_TRBCTL_CONTROL_DATA, 1);
+               }
+
+               transfer_size = roundup((req->request.length - transfer_size),
+                                       maxpacket);
 
                dwc->ep0_bounced = true;
 
@@ -935,8 +970,8 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
                 * TRBs to handle the transfer.
                 */
                ret = dwc3_ep0_start_trans(dwc, dep->number,
-                               dwc->ep0_bounce_addr, transfer_size,
-                               DWC3_TRBCTL_CONTROL_DATA);
+                                          dwc->ep0_bounce_addr, transfer_size,
+                                          DWC3_TRBCTL_CONTROL_DATA, 0);
        } else {
                ret = usb_gadget_map_request(&dwc->gadget, &req->request,
                                dep->number);
@@ -946,7 +981,8 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
                }
 
                ret = dwc3_ep0_start_trans(dwc, dep->number, req->request.dma,
-                               req->request.length, DWC3_TRBCTL_CONTROL_DATA);
+                                          req->request.length,
+                                          DWC3_TRBCTL_CONTROL_DATA, 0);
        }
 
        WARN_ON(ret < 0);
@@ -961,7 +997,7 @@ static int dwc3_ep0_start_control_status(struct dwc3_ep *dep)
                : DWC3_TRBCTL_CONTROL_STATUS2;
 
        return dwc3_ep0_start_trans(dwc, dep->number,
-                       dwc->ctrl_req_addr, 0, type);
+                       dwc->ctrl_req_addr, 0, type, 0);
 }
 
 static void __dwc3_ep0_do_control_status(struct dwc3 *dwc, struct dwc3_ep *dep)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 8560b88dd11655b56a0a1ee89d2a22e5c8a7a0c9..c8b749915c2ba690f9a74c2194960917d33faa86 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2580,7 +2580,7 @@ int dwc3_gadget_init(struct dwc3 *dwc)
                goto err0;
        }
 
-       dwc->ep0_trb = dma_alloc_coherent(sizeof(*dwc->ep0_trb),
+       dwc->ep0_trb = dma_alloc_coherent(sizeof(*dwc->ep0_trb) * 2,
                                          (unsigned long *)&dwc->ep0_trb_addr);
        if (!dwc->ep0_trb) {
                dev_err(dwc->dev, "failed to allocate ep0 trb\n");