[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-ID: <1423223735-32512-2-git-send-email-kishon@ti.com>
Date: Fri, 6 Feb 2015 17:25:35 +0530
From: Kishon Vijay Abraham I <kishon@...com>
To: <balbi@...com>
CC: <linux-usb@...r.kernel.org>, <linux-omap@...r.kernel.org>,
<linux-kernel@...r.kernel.org>, <gregkh@...uxfoundation.org>,
<kishon@...com>
Subject: [RFC PATCH 2/2] 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@...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-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists