[PATCH 4/5] usb: dwc3: ep0: Add chained TRB support

[Kishon Vijay Abraham I]

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 <kis...@ti.com>
---
 drivers/usb/dwc3/ep0.c    |   16 +++++++++++++---
 drivers/usb/dwc3/gadget.c |    2 +-
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index d1a2be1..6847afe 100644
--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -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(&params, 0, sizeof(params));
        params.param0 = upper_32_bits(dwc->ep0_trb_addr);
        params.param1 = lower_32_bits(dwc->ep0_trb_addr);
diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 8946c32..b8d0a84 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2677,7 +2677,7 @@ 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