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>

diff --git a/drivers/usb/dwc3/ep0.c b/drivers/usb/dwc3/ep0.c
index 3f709a3ef31a87646ab855fe1aa35558a67a7c73..ebf2621fae5d0b4627c507b839b8edc1bb616753 100644 (file)
--- 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 d97fcfa8fe87ec03f7ee717c3118be3f9a7a2513..2feed9e03583fd4f422b7757167abd92d2ebb3c5 100644 (file)
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -2687,7 +2687,7 @@ 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");