From 979283c0a3708ee0ac48a858399a71075458e098 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Wed, 4 Jul 2012 09:18:02 +0200
Subject: [PATCH] --- yaml --- r: 316988 b: refs/heads/master c:
 19181bc50e1b8e92a7a3b3d78637c6dc5c0b5a1b h: refs/heads/master v: v3

---
 [refs]                             |  2 +-
 trunk/drivers/usb/core/devio.c     | 17 +++++++++++++++++
 trunk/drivers/usb/host/xhci.c      |  2 ++
 trunk/include/linux/usb.h          |  5 +++++
 trunk/include/linux/usbdevice_fs.h |  7 +++++++
 5 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index 9fa533ddf000..25bbe4a9ad32 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 2102e06a5f2e414694921f23591f072a5ba7db9f
+refs/heads/master: 19181bc50e1b8e92a7a3b3d78637c6dc5c0b5a1b
diff --git a/trunk/drivers/usb/core/devio.c b/trunk/drivers/usb/core/devio.c
index 62679bc031fb..0b387c1a8b7e 100644
--- a/trunk/drivers/usb/core/devio.c
+++ b/trunk/drivers/usb/core/devio.c
@@ -1824,6 +1824,20 @@ static int proc_release_port(struct dev_state *ps, void __user *arg)
 	return usb_hub_release_port(ps->dev, portnum, ps);
 }
 
+static int proc_get_capabilities(struct dev_state *ps, void __user *arg)
+{
+	__u32 caps;
+
+	caps = USBDEVFS_CAP_ZERO_PACKET | USBDEVFS_CAP_NO_PACKET_SIZE_LIM;
+	if (!ps->dev->bus->no_stop_on_short)
+		caps |= USBDEVFS_CAP_BULK_CONTINUATION;
+
+	if (put_user(caps, (__u32 __user *)arg))
+		return -EFAULT;
+
+	return 0;
+}
+
 /*
  * NOTE:  All requests here that have interface numbers as parameters
  * are assuming that somehow the configuration has been prevented from
@@ -1994,6 +2008,9 @@ static long usbdev_do_ioctl(struct file *file, unsigned int cmd,
 		snoop(&dev->dev, "%s: RELEASE_PORT\n", __func__);
 		ret = proc_release_port(ps, p);
 		break;
+	case USBDEVFS_GET_CAPABILITIES:
+		ret = proc_get_capabilities(ps, p);
+		break;
 	}
 	usb_unlock_device(dev);
 	if (ret >= 0)
diff --git a/trunk/drivers/usb/host/xhci.c b/trunk/drivers/usb/host/xhci.c
index a979cd0dbe0f..7648b2d4b268 100644
--- a/trunk/drivers/usb/host/xhci.c
+++ b/trunk/drivers/usb/host/xhci.c
@@ -4450,6 +4450,8 @@ int xhci_gen_setup(struct usb_hcd *hcd, xhci_get_quirks_t get_quirks)
 
 	/* Accept arbitrarily long scatter-gather lists */
 	hcd->self.sg_tablesize = ~0;
+	/* XHCI controllers don't stop the ep queue on short packets :| */
+	hcd->self.no_stop_on_short = 1;
 
 	if (usb_hcd_is_primary_hcd(hcd)) {
 		xhci = kzalloc(sizeof(struct xhci_hcd), GFP_KERNEL);
diff --git a/trunk/include/linux/usb.h b/trunk/include/linux/usb.h
index f717fbdaee8e..d4f9de1acd45 100644
--- a/trunk/include/linux/usb.h
+++ b/trunk/include/linux/usb.h
@@ -331,6 +331,11 @@ struct usb_bus {
 	u8 otg_port;			/* 0, or number of OTG/HNP port */
 	unsigned is_b_host:1;		/* true during some HNP roleswitches */
 	unsigned b_hnp_enable:1;	/* OTG: did A-Host enable HNP? */
+	unsigned no_stop_on_short:1;    /*
+					 * Quirk: some controllers don't stop
+					 * the ep queue on a short transfer
+					 * with the URB_SHORT_NOT_OK flag set.
+					 */
 	unsigned sg_tablesize;		/* 0 or largest number of sg list entries */
 
 	int devnum_next;		/* Next open device number in
diff --git a/trunk/include/linux/usbdevice_fs.h b/trunk/include/linux/usbdevice_fs.h
index 15591d2ea400..07b2ceaaad70 100644
--- a/trunk/include/linux/usbdevice_fs.h
+++ b/trunk/include/linux/usbdevice_fs.h
@@ -125,6 +125,11 @@ struct usbdevfs_hub_portinfo {
 	char port [127];	/* e.g. port 3 connects to device 27 */
 };
 
+/* Device capability flags */
+#define USBDEVFS_CAP_ZERO_PACKET		0x01
+#define USBDEVFS_CAP_BULK_CONTINUATION		0x02
+#define USBDEVFS_CAP_NO_PACKET_SIZE_LIM		0x04
+
 #ifdef __KERNEL__
 #ifdef CONFIG_COMPAT
 #include <linux/compat.h>
@@ -204,4 +209,6 @@ struct usbdevfs_ioctl32 {
 #define USBDEVFS_CONNECT           _IO('U', 23)
 #define USBDEVFS_CLAIM_PORT        _IOR('U', 24, unsigned int)
 #define USBDEVFS_RELEASE_PORT      _IOR('U', 25, unsigned int)
+#define USBDEVFS_GET_CAPABILITIES  _IOR('U', 26, __u32)
+
 #endif /* _LINUX_USBDEVICE_FS_H */