commit 2abd9d5fa60f90cd99801687904f528156d31e18
author Kishon Vijay Abraham I <kishon@ti.com> Mon Jul 27 12:25:31 2015 +0530
committer Felipe Balbi <balbi@ti.com> Thu Jul 30 11:43:34 2015 -0500
tree 5cd9b1e4dfe8028161bd82911cb3e62b41cd8efa
parent 368ca113ca0a41bbf60be6886bbbd238523c6fba

usb: dwc3: ep0: Add chained TRB support

Add chained TRB support to ep0. Now TRB's can be chained just by
invoking _dwc3_ep0_start_trans_ with 'chain' parameter set to true.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

drivers/usb/dwc3/ep0.c

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 3f709a3..ebf2621 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -70,7 +70,10 @@
 		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 @@
 	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(&params, 0, sizeof(params));
 	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
 	params.param1 = lower_32_bits(dwc->ep0_trb_addr);

drivers/usb/dwc3/gadget.c

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index d97fcfa..2feed9e 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2687,7 +2687,7 @@
 		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");