Merge tag 'for-v4.6-rc/omap-fixes-a' of git://git.kernel.org/pub/scm/linux/kernel/git/pjw/omap-pending into omap-for-v4.6/fixes

ARM: OMAP2+: first hwmod fix for v4.6-rc

Fix a longstanding bug in the hwmod code that could cause
hardware SYSCONFIG register values to not match the kernel's
idea of what they should be, and that could result in lower
performance during IP block idle entry.

Basic build, boot, and PM test logs are available here:

http://www.pwsan.com/omap/testlogs/omap-hwmod-fixes-a-for-v4.6-rc/20160326231727/

1 files changed, 81 insertions, 10 deletions

diff --git a/drivers/net/xen-netback/xenbus.c b/drivers/net/xen-netback/xenbus.c
index 56ebd8267386..bd182cd55dda 100644
--- a/drivers/net/xen-netback/xenbus.c
+++ b/drivers/net/xen-netback/xenbus.c
@@ -327,7 +327,7 @@ static int netback_probe(struct xenbus_device *dev,
 			goto abort_transaction;
 		}
 
-		/* We support multicast-control. */
+		/* We support dynamic multicast-control. */
 		err = xenbus_printf(xbt, dev->nodename,
 				    "feature-multicast-control", "%d", 1);
 		if (err) {
@@ -335,6 +335,14 @@ static int netback_probe(struct xenbus_device *dev,
 			goto abort_transaction;
 		}
 
+		err = xenbus_printf(xbt, dev->nodename,
+				    "feature-dynamic-multicast-control",
+				    "%d", 1);
+		if (err) {
+			message = "writing feature-dynamic-multicast-control";
+			goto abort_transaction;
+		}
+
 		err = xenbus_transaction_end(xbt, 0);
 	} while (err == -EAGAIN);
 
@@ -503,8 +511,6 @@ static void set_backend_state(struct backend_info *be,
 			switch (state) {
 			case XenbusStateInitWait:
 			case XenbusStateConnected:
-				pr_info("%s: prepare for reconnect\n",
-					be->dev->nodename);
 				backend_switch_state(be, XenbusStateInitWait);
 				break;
 			case XenbusStateClosing:
@@ -683,7 +689,8 @@ static void xen_net_rate_changed(struct xenbus_watch *watch,
 	}
 }
 
-static int xen_register_watchers(struct xenbus_device *dev, struct xenvif *vif)
+static int xen_register_credit_watch(struct xenbus_device *dev,
+				     struct xenvif *vif)
 {
 	int err = 0;
 	char *node;
@@ -708,7 +715,7 @@ static int xen_register_watchers(struct xenbus_device *dev, struct xenvif *vif)
 	return err;
 }
 
-static void xen_unregister_watchers(struct xenvif *vif)
+static void xen_unregister_credit_watch(struct xenvif *vif)
 {
 	if (vif->credit_watch.node) {
 		unregister_xenbus_watch(&vif->credit_watch);
@@ -717,6 +724,75 @@ static void xen_unregister_watchers(struct xenvif *vif)
 	}
 }
 
+static void xen_mcast_ctrl_changed(struct xenbus_watch *watch,
+				   const char **vec, unsigned int len)
+{
+	struct xenvif *vif = container_of(watch, struct xenvif,
+					  mcast_ctrl_watch);
+	struct xenbus_device *dev = xenvif_to_xenbus_device(vif);
+	int val;
+
+	if (xenbus_scanf(XBT_NIL, dev->otherend,
+			 "request-multicast-control", "%d", &val) < 0)
+		val = 0;
+	vif->multicast_control = !!val;
+}
+
+static int xen_register_mcast_ctrl_watch(struct xenbus_device *dev,
+					 struct xenvif *vif)
+{
+	int err = 0;
+	char *node;
+	unsigned maxlen = strlen(dev->otherend) +
+		sizeof("/request-multicast-control");
+
+	if (vif->mcast_ctrl_watch.node) {
+		pr_err_ratelimited("Watch is already registered\n");
+		return -EADDRINUSE;
+	}
+
+	node = kmalloc(maxlen, GFP_KERNEL);
+	if (!node) {
+		pr_err("Failed to allocate memory for watch\n");
+		return -ENOMEM;
+	}
+	snprintf(node, maxlen, "%s/request-multicast-control",
+		 dev->otherend);
+	vif->mcast_ctrl_watch.node = node;
+	vif->mcast_ctrl_watch.callback = xen_mcast_ctrl_changed;
+	err = register_xenbus_watch(&vif->mcast_ctrl_watch);
+	if (err) {
+		pr_err("Failed to set watcher %s\n",
+		       vif->mcast_ctrl_watch.node);
+		kfree(node);
+		vif->mcast_ctrl_watch.node = NULL;
+		vif->mcast_ctrl_watch.callback = NULL;
+	}
+	return err;
+}
+
+static void xen_unregister_mcast_ctrl_watch(struct xenvif *vif)
+{
+	if (vif->mcast_ctrl_watch.node) {
+		unregister_xenbus_watch(&vif->mcast_ctrl_watch);
+		kfree(vif->mcast_ctrl_watch.node);
+		vif->mcast_ctrl_watch.node = NULL;
+	}
+}
+
+static void xen_register_watchers(struct xenbus_device *dev,
+				  struct xenvif *vif)
+{
+	xen_register_credit_watch(dev, vif);
+	xen_register_mcast_ctrl_watch(dev, vif);
+}
+
+static void xen_unregister_watchers(struct xenvif *vif)
+{
+	xen_unregister_mcast_ctrl_watch(vif);
+	xen_unregister_credit_watch(vif);
+}
+
 static void unregister_hotplug_status_watch(struct backend_info *be)
 {
 	if (be->have_hotplug_status_watch) {
@@ -1030,11 +1106,6 @@ static int read_xenbus_vif_flags(struct backend_info *be)
 		val = 0;
 	vif->ipv6_csum = !!val;
 
-	if (xenbus_scanf(XBT_NIL, dev->otherend, "request-multicast-control",
-			 "%d", &val) < 0)
-		val = 0;
-	vif->multicast_control = !!val;
-
 	return 0;
 }