[PATCH 3.16 135/370] usb: dwc3: ep0: add dwc3_ep0_prepare_one_trb()

Ben Hutchings
2017-03-10T13:45:33Z

From: Felipe Balbi <felipe.balbi@linux.intel.com>

commit 7931ec86c1b738e4e90e58c6d95e5f720d45ee56 upstream.

For now this is just a cleanup patch, no functional
changes. We will be using the new function to fix a
bug introduced long ago by commit 0416e494ce7d
("usb: dwc3: ep0: correct cache sync issue in case
of ep0_bounced") and further worsened by commit
c0bd5456a470 ("usb: dwc3: ep0: handle non maxpacket
aligned transfers > 512")

Reported-by: Janusz Dziedzic <januszx.dziedzic@linux.intel.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
[bwh: Backported to 3.16:
- dwc3_ep0_start_trans() doesn't have a 'chain' parameter, so don't
give dwc3_ep0_prepare_one_trb() this parameter
- Also delete a debug log statement, removed earlier upstream
- Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/usb/dwc3/ep0.c | 26 ++++++++++++++++----------
1 file changed, 16 insertions(+), 10 deletions(-)

--- a/drivers/usb/dwc3/ep0.c
+++ b/drivers/usb/dwc3/ep0.c
@@ -54,20 +54,13 @@ static const char *dwc3_ep0_state_string
}
}

-static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
- u32 len, u32 type)
+static void dwc3_ep0_prepare_one_trb(struct dwc3 *dwc, u8 epnum,
+ dma_addr_t buf_dma, u32 len, u32 type)
{
- struct dwc3_gadget_ep_cmd_params params;
struct dwc3_trb *trb;
struct dwc3_ep *dep;

- int ret;
-
dep = dwc->eps[epnum];
- if (dep->flags & DWC3_EP_BUSY) {
- dev_vdbg(dwc->dev, "%s: still busy\n", dep->name);
- return 0;
- }

trb = dwc->ep0_trb;

@@ -80,6 +73,20 @@ static int dwc3_ep0_start_trans(struct d
| DWC3_TRB_CTRL_LST
| DWC3_TRB_CTRL_IOC
| DWC3_TRB_CTRL_ISP_IMI);
+}
+
+static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
+ u32 len, u32 type)
+{
+ struct dwc3_gadget_ep_cmd_params params;
+ struct dwc3_ep *dep;
+ int ret;
+
+ dep = dwc->eps[epnum];
+ if (dep->flags & DWC3_EP_BUSY)
+ return 0;
+
+ dwc3_ep0_prepare_one_trb(dwc, epnum, buf_dma, len, type);

memset(&params, 0, sizeof(params));
params.param0 = upper_32_bits(dwc->ep0_trb_addr);