[ 3.5.y.z extended stable ] Patch "USB: DWC3: Generate interrupt on each TRB as default option" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    USB: DWC3: Generate interrupt on each TRB as default option

to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.5.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 2ad5d650f93b512f032dadff3e6259ae75e832b9 Mon Sep 17 00:00:00 2001
From: Pratyush Anand <pratyush.anand at st.com>
Date: Mon, 21 May 2012 12:42:54 +0530
Subject: [PATCH] USB: DWC3: Generate interrupt on each TRB as default option

commit 206dd69a62a06197b308fa0decfd0b649fcc2811 upstream.

Currently in case of isoc, interrupt is programmed after each
TRB_NUM/4 ie 8th TRB. A TRB is programmed against each submitted
request from gadget. If we do not want to limit the minimum number of
necessary request to be submitted from gadget then we must receive
interrupt on each TRB submission. There can be such situation with a
gadget working with ping-pong buffer.

If a gadget does not want to receive interrupt after each request
completion then it may set no_interrupt flag.

Signed-off-by: Pratyush Anand <pratyush.anand at st.com>
Signed-off-by: Felipe Balbi <balbi at ti.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/usb/dwc3/gadget.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
index 1f53210..edfff45 100644
--- a/drivers/usb/dwc3/gadget.c
+++ b/drivers/usb/dwc3/gadget.c
@@ -744,8 +744,7 @@ static void dwc3_prepare_one_trb(struct dwc3_ep *dep,
 	case USB_ENDPOINT_XFER_ISOC:
 		trb->ctrl = DWC3_TRBCTL_ISOCHRONOUS_FIRST;

-		/* IOC every DWC3_TRB_NUM / 4 so we can refill */
-		if (!(cur_slot % (DWC3_TRB_NUM / 4)))
+		if (!req->request.no_interrupt)
 			trb->ctrl |= DWC3_TRB_CTRL_IOC;
 		break;

--
1.8.1.2