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 <kis...@ti.com> --- *) Did eumeration testing with g_zero in kernel *) Similar patch was added in u-boot. With DFU, was able to create a scenario where the request length is not max packet aligned and is bigger than DWC3_EP0_BOUNCE_SIZE (512 bytes). In that case, 2 chained TRBs will be used. drivers/usb/dwc3/ep0.c | 65 +++++++++++++++++++++++++++++++++------------ drivers/usb/dwc3/gadget.c | 2 +- 2 files changed, 49 insertions(+), 18 deletions(-) diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c index 24b7925..3b728b8 100644 --- a/drivers/usb/dwc3/ep0.c +++ b/drivers/usb/dwc3/ep0.c @@ -56,7 +56,7 @@ 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; @@ -70,7 +70,10 @@ 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); @@ -78,10 +81,17 @@ 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); + + if (chain) + return 0; + memset(¶ms, 0, sizeof(params)); params.param0 = upper_32_bits(dwc->ep0_trb_addr); params.param1 = lower_32_bits(dwc->ep0_trb_addr); @@ -302,7 +312,7 @@ 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, false); WARN_ON(ret < 0); } @@ -817,6 +827,22 @@ static void dwc3_ep0_complete_data(struct dwc3 *dwc, maxp = ep0->endpoint.maxpacket; + /* Handle the first TRB before handling the bounce buffer if the request + * length is greater than the bounce buffer size + */ + if (!IS_ALIGNED(ur->length, maxp) && + ur->length > DWC3_EP0_BOUNCE_SIZE) { + transfer_size = (ur->length / maxp) * maxp; + transferred = transfer_size - length; + buf = (u8 *)buf + transferred; + ur->actual += transferred; + + trb++; + length = trb->size & DWC3_TRB_SIZE_MASK; + + ep0->free_slot = 0; + } + if (dwc->ep0_bounced) { transfer_size = roundup((ur->length - transfer_size), maxp); @@ -844,7 +870,7 @@ 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, false); WARN_ON(ret < 0); } } @@ -928,7 +954,7 @@ 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); + DWC3_TRBCTL_CONTROL_DATA, false); } else if (!IS_ALIGNED(req->request.length, dep->endpoint.maxpacket) && (dep->number == 0)) { u32 transfer_size = 0; @@ -941,22 +967,26 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc, return; } - WARN_ON(req->request.length > DWC3_EP0_BOUNCE_SIZE); - maxpacket = dep->endpoint.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, + true); + } + transfer_size = roundup((req->request.length - transfer_size), maxpacket); dwc->ep0_bounced = true; - /* - * REVISIT in case request length is bigger than - * DWC3_EP0_BOUNCE_SIZE we will need two chained - * TRBs to handle the transfer. - */ ret = dwc3_ep0_start_trans(dwc, dep->number, dwc->ep0_bounce_addr, transfer_size, - DWC3_TRBCTL_CONTROL_DATA); + DWC3_TRBCTL_CONTROL_DATA, false); } else { ret = usb_gadget_map_request(&dwc->gadget, &req->request, dep->number); @@ -966,7 +996,8 @@ 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, + false); } WARN_ON(ret < 0); @@ -981,7 +1012,7 @@ 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, false); } 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 a03a485..7212b93 100644 --- a/drivers/usb/dwc3/gadget.c +++ b/drivers/usb/dwc3/gadget.c @@ -2682,7 +2682,7 @@ int dwc3_gadget_init(struct dwc3 *dwc) goto err0; } - dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb), + dwc->ep0_trb = dma_alloc_coherent(dwc->dev, sizeof(*dwc->ep0_trb) * 2, &dwc->ep0_trb_addr, GFP_KERNEL); if (!dwc->ep0_trb) { dev_err(dwc->dev, "failed to allocate ep0 trb\n"); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html