From c0bd5456a470223e331a9e9e93b4a7425ecfaabb Mon Sep 17 00:00:00 2001
From: Kishon Vijay Abraham I <kishon@ti.com>
Date: Mon, 27 Jul 2015 12:25:32 +0530
Subject: [PATCH] usb: dwc3: ep0: handle non maxpacket aligned transfers > 512
Use chained TRB mechanism to handle non maxpacket aligned transfers
greater than bounce buffer size. With this the first TRB will be programmed
to receive 'ALIGN(ur->length - maxp, maxp)' data and the second TRB
will be programmed to receive the remaining data using bounce buffer.
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
---
drivers/usb/dwc3/ep0.c | 42 ++++++++++++++++++++++++++++--------------
1 file changed, 28 insertions(+), 14 deletions(-)
diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index ebf2621fae5d..5320e939e090 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -834,13 +834,26 @@ 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 = ALIGN(ur->length - maxp, maxp);
+ transferred = transfer_size - length;
+ buf = (u8 *)buf + transferred;
+ ur->actual += transferred;
+ remaining_ur_length -= transferred;
+
+ trb++;
+ length = trb->size & DWC3_TRB_SIZE_MASK;
+
+ ep0->free_slot = 0;
+ }
+
transfer_size = roundup((ur->length - transfer_size),
maxp);
- /* Maximum of DWC3_EP0_BOUNCE_SIZE can only be received */
- if (transfer_size > DWC3_EP0_BOUNCE_SIZE)
- transfer_size = DWC3_EP0_BOUNCE_SIZE;
-
transferred = min_t(u32, remaining_ur_length,
transfer_size - length);
memcpy(buf, dwc->ep0_bounce, transferred);
@@ -963,21 +976,22 @@ static void __dwc3_ep0_do_control_data(struct dwc3 *dwc,
}
maxpacket = dep->endpoint.maxpacket;
- transfer_size = roundup((req->request.length - transfer_size),
- maxpacket);
- if (transfer_size > DWC3_EP0_BOUNCE_SIZE) {
- dev_WARN(dwc->dev, "bounce buf can't handle req len\n");
- transfer_size = DWC3_EP0_BOUNCE_SIZE;
+ if (req->request.length > DWC3_EP0_BOUNCE_SIZE) {
+ transfer_size = ALIGN(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, false);
--
2.34.1