Patch "usb: dwc3: ep0: add dwc3_ep0_prepare_one_trb()" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

    usb: dwc3: ep0: add dwc3_ep0_prepare_one_trb()

to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:

     usb-dwc3-ep0-add-dwc3_ep0_prepare_one_trb.patch

and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Felipe Balbi <[email protected]>
Date: Tue, 20 Dec 2016 13:57:32 +0200
Subject: usb: dwc3: ep0: add dwc3_ep0_prepare_one_trb()

From: Felipe Balbi <[email protected]>

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")

---
 drivers/usb/dwc3/ep0.c |   30 ++++++++++++++++++------------
 1 file changed, 18 insertions(+), 12 deletions(-)

@@ -55,20 +55,13 @@ 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, bool chain)
+static void dwc3_ep0_prepare_one_trb(struct dwc3 *dwc, u8 epnum,
+		dma_addr_t buf_dma, u32 len, u32 type, bool chain)
 {
-	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) {
-		dwc3_trace(trace_dwc3_ep0, "%s still busy", dep->name);
-		return 0;
-	}
 
 	trb = &dwc->ep0_trb[dep->trb_enqueue];
 

@@ -89,15 +82,28 @@ static int dwc3_ep0_start_trans(struct d
 		trb->ctrl |= (DWC3_TRB_CTRL_IOC
 				| DWC3_TRB_CTRL_LST);
 
-	if (chain)
+	trace_dwc3_prepare_trb(dep, trb);
+}
+
+static int dwc3_ep0_start_trans(struct dwc3 *dwc, u8 epnum, dma_addr_t buf_dma,
+		u32 len, u32 type, bool chain)
+{
+	struct dwc3_gadget_ep_cmd_params params;
+	struct dwc3_ep			*dep;
+	int				ret;
+
+	dep = dwc->eps[epnum];
+	if (dep->flags & DWC3_EP_BUSY) {
+		dwc3_trace(trace_dwc3_ep0, "%s still busy", dep->name);
 		return 0;
+	}
+
+	dwc3_ep0_prepare_one_trb(dwc, epnum, buf_dma, len, type, chain);
 
 	memset(&params, 0, sizeof(params));
 	params.param0 = upper_32_bits(dwc->ep0_trb_addr);
 	params.param1 = lower_32_bits(dwc->ep0_trb_addr);
 
-	trace_dwc3_prepare_trb(dep, trb);
-
 	ret = dwc3_send_gadget_ep_cmd(dep, DWC3_DEPCMD_STARTTRANSFER, &params);
 	if (ret < 0) {
 		dwc3_trace(trace_dwc3_ep0, "%s STARTTRANSFER failed",

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/usb-gadget-fix-request-length-error-for-isoc-transfer.patch queue-4.9/usb-dummy-hcd-fix-bug-in-stop_activity-handle-ep0.patch queue-4.9/usb-dwc3-core-avoid-overflow-events.patch queue-4.9/usb-gadgetfs-fix-use-after-free-bug.patch queue-4.9/usb-dwc3-pci-fix-dr_mode-misspelling.patch queue-4.9/usb-gadget-composite-test-get_alt-presence-instead-of-set_alt.patch queue-4.9/usb-dwc3-ep0-explicitly-call-dwc3_ep0_prepare_one_trb.patch queue-4.9/usb-phy-am335x-control-fix-device-and-of_node-leaks.patch queue-4.9/usb-gadgetfs-restrict-upper-bound-on-device-configuration-size.patch queue-4.9/usb-gadget-udc-core-fix-return-code-of-usb_gadget_probe_driver.patch queue-4.9/usb-gadget-fix-second-argument-of-percpu_ida_alloc.patch queue-4.9/usb-gadgetfs-fix-checks-of-wtotallength-in-config-descriptors.patch queue-4.9/usb-dwc3-gadget-always-unmap-ep0-requests.patch queue-4.9/usb-dwc3-ep0-add-dwc3_ep0_prepare_one_trb.patch queue-4.9/usb-dwc3-gadget-fix-full-speed-mode.patch queue-4.9/usb-dwc3-pci-add-intel-gemini-lake-pci-id.patch queue-4.9/usb-gadgetfs-fix-unbounded-memory-allocation-bug.patch