[3.16.y-ckt stable] Patch "usb: chipidea: udc: using the correct stall implementation" has been added to staging queue

[Kamal Mostafa]

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

    usb: chipidea: udc: using the correct stall implementation

to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue

This patch is scheduled to be released in version 3.19.8-ckt9.

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

For more information about the 3.16.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From 7c1a9e59972036003d6511c95ab759d081900807 Mon Sep 17 00:00:00 2001
From: Peter Chen <peter.chen at freescale.com>
Date: Mon, 24 Aug 2015 14:10:07 +0800
Subject: usb: chipidea: udc: using the correct stall implementation

commit 56ffa1d154c7e12af16273f0cdc42690dd05caf5 upstream.

According to spec, there are functional and protocol stalls.

For functional stall, it is for bulk and interrupt endpoints,
below are cases for it:
- Host sends SET_FEATURE request for Set-Halt, the udc driver
needs to set stall, and return true unconditionally.
- The gadget driver may call usb_ep_set_halt to stall certain
endpoints, if there is a transfer in pending, the udc driver
should not set stall, and return -EAGAIN accordingly.
These two kinds of stall need to be cleared by host using CLEAR_FEATURE
request (Clear-Halt).

For protocol stall, it is for control endpoint, this stall will
be set if the control request has failed. This stall will be
cleared by next setup request (hardware will do it).

It fixed usbtest (drivers/usb/misc/usbtest.c) Test 13 "set/clear halt"
test failure, meanwhile, this change has been verified by
USB2 CV Compliance Test and MSC Tests.

Cc: Alan Stern <stern at rowland.harvard.edu>
Cc: Felipe Balbi <balbi at ti.com>
Signed-off-by: Peter Chen <peter.chen at freescale.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/usb/chipidea/udc.c | 84 ++++++++++++++++++++++++----------------------
 1 file changed, 44 insertions(+), 40 deletions(-)

diff --git a/drivers/usb/chipidea/udc.c b/drivers/usb/chipidea/udc.c
index 7c14565..bd986ce 100644
--- a/drivers/usb/chipidea/udc.c
+++ b/drivers/usb/chipidea/udc.c
@@ -638,6 +638,44 @@ __acquires(hwep->lock)
 	return 0;
 }

+static int _ep_set_halt(struct usb_ep *ep, int value, bool check_transfer)
+{
+	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
+	int direction, retval = 0;
+	unsigned long flags;
+
+	if (ep == NULL || hwep->ep.desc == NULL)
+		return -EINVAL;
+
+	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
+		return -EOPNOTSUPP;
+
+	spin_lock_irqsave(hwep->lock, flags);
+
+	if (value && hwep->dir == TX && check_transfer &&
+		!list_empty(&hwep->qh.queue) &&
+			!usb_endpoint_xfer_control(hwep->ep.desc)) {
+		spin_unlock_irqrestore(hwep->lock, flags);
+		return -EAGAIN;
+	}
+
+	direction = hwep->dir;
+	do {
+		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
+
+		if (!value)
+			hwep->wedge = 0;
+
+		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
+			hwep->dir = (hwep->dir == TX) ? RX : TX;
+
+	} while (hwep->dir != direction);
+
+	spin_unlock_irqrestore(hwep->lock, flags);
+	return retval;
+}
+
+
 /**
  * _gadget_stop_activity: stops all USB activity, flushes & disables all endpts
  * @gadget: gadget
@@ -1033,7 +1071,7 @@ __acquires(ci->lock)
 				num += ci->hw_ep_max / 2;

 			spin_unlock(&ci->lock);
-			err = usb_ep_set_halt(&ci->ci_hw_ep[num].ep);
+			err = _ep_set_halt(&ci->ci_hw_ep[num].ep, 1, false);
 			spin_lock(&ci->lock);
 			if (!err)
 				isr_setup_status_phase(ci);
@@ -1092,8 +1130,8 @@ delegate:

 	if (err < 0) {
 		spin_unlock(&ci->lock);
-		if (usb_ep_set_halt(&hwep->ep))
-			dev_err(ci->dev, "error: ep_set_halt\n");
+		if (_ep_set_halt(&hwep->ep, 1, false))
+			dev_err(ci->dev, "error: _ep_set_halt\n");
 		spin_lock(&ci->lock);
 	}
 }
@@ -1124,9 +1162,9 @@ __acquires(ci->lock)
 					err = isr_setup_status_phase(ci);
 				if (err < 0) {
 					spin_unlock(&ci->lock);
-					if (usb_ep_set_halt(&hwep->ep))
+					if (_ep_set_halt(&hwep->ep, 1, false))
 						dev_err(ci->dev,
-							"error: ep_set_halt\n");
+						"error: _ep_set_halt\n");
 					spin_lock(&ci->lock);
 				}
 			}
@@ -1369,41 +1407,7 @@ static int ep_dequeue(struct usb_ep *ep, struct usb_request *req)
  */
 static int ep_set_halt(struct usb_ep *ep, int value)
 {
-	struct ci_hw_ep *hwep = container_of(ep, struct ci_hw_ep, ep);
-	int direction, retval = 0;
-	unsigned long flags;
-
-	if (ep == NULL || hwep->ep.desc == NULL)
-		return -EINVAL;
-
-	if (usb_endpoint_xfer_isoc(hwep->ep.desc))
-		return -EOPNOTSUPP;
-
-	spin_lock_irqsave(hwep->lock, flags);
-
-#ifndef STALL_IN
-	/* g_file_storage MS compliant but g_zero fails chapter 9 compliance */
-	if (value && hwep->type == USB_ENDPOINT_XFER_BULK && hwep->dir == TX &&
-	    !list_empty(&hwep->qh.queue)) {
-		spin_unlock_irqrestore(hwep->lock, flags);
-		return -EAGAIN;
-	}
-#endif
-
-	direction = hwep->dir;
-	do {
-		retval |= hw_ep_set_halt(hwep->ci, hwep->num, hwep->dir, value);
-
-		if (!value)
-			hwep->wedge = 0;
-
-		if (hwep->type == USB_ENDPOINT_XFER_CONTROL)
-			hwep->dir = (hwep->dir == TX) ? RX : TX;
-
-	} while (hwep->dir != direction);
-
-	spin_unlock_irqrestore(hwep->lock, flags);
-	return retval;
+	return _ep_set_halt(ep, value, true);
 }

 /**
--
1.9.1