Revert "mvebu: remove linux 4.4 support"

This reverts commit 51397d7d95d9f5e210a5557f65de1fa21e6f5921.
There are some unresolved random crashes on WRT1900AC v1 that still need
to be sorted out

Signed-off-by: Felix Fietkau <nbd@nbd.name>

1 files changed, 183 insertions, 0 deletions

diff --git a/target/linux/mvebu/patches-4.4/125-phy-provide-a-hook-for-link-up-link-down-events.patch b/target/linux/mvebu/patches-4.4/125-phy-provide-a-hook-for-link-up-link-down-events.patch
new file mode 100644
index 0000000000..b00968961f
--- /dev/null
+++ b/target/linux/mvebu/patches-4.4/125-phy-provide-a-hook-for-link-up-link-down-events.patch
@@ -0,0 +1,183 @@
+From d8b4e728f598d3c8a9b219d4679d5de350caa082 Mon Sep 17 00:00:00 2001
+From: Russell King <rmk+kernel@arm.linux.org.uk>
+Date: Fri, 18 Sep 2015 14:42:16 +0100
+Subject: [PATCH 714/744] phy: provide a hook for link up/link down events
+
+Sometimes, we need to do additional work between the PHY coming up and
+marking the carrier present - for example, we may need to wait for the
+PHY to MAC link to finish negotiation.  This changes phylib to provide
+a notification function pointer which avoids the built-in
+netif_carrier_on() and netif_carrier_off() functions.
+
+Standard ->adjust_link functionality is provided by hooking a helper
+into the new ->phy_link_change method.
+
+Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
+Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
+---
+ drivers/net/phy/phy.c        | 42 ++++++++++++++++++++++--------------------
+ drivers/net/phy/phy_device.c | 14 ++++++++++++++
+ include/linux/phy.h          |  1 +
+ 3 files changed, 37 insertions(+), 20 deletions(-)
+
+--- a/drivers/net/phy/phy.c
++++ b/drivers/net/phy/phy.c
+@@ -849,6 +849,16 @@ void phy_start(struct phy_device *phydev
+ }
+ EXPORT_SYMBOL(phy_start);
+ 
++static void phy_link_up(struct phy_device *phydev)
++{
++	phydev->phy_link_change(phydev, true, true);
++}
++
++static void phy_link_down(struct phy_device *phydev, bool do_carrier)
++{
++	phydev->phy_link_change(phydev, false, do_carrier);
++}
++
+ /**
+  * phy_state_machine - Handle the state machine
+  * @work: work_struct that describes the work to be done
+@@ -890,8 +900,7 @@ void phy_state_machine(struct work_struc
+ 		/* If the link is down, give up on negotiation for now */
+ 		if (!phydev->link) {
+ 			phydev->state = PHY_NOLINK;
+-			netif_carrier_off(phydev->attached_dev);
+-			phydev->adjust_link(phydev->attached_dev);
++			phy_link_down(phydev, true);
+ 			break;
+ 		}
+ 
+@@ -903,9 +912,7 @@ void phy_state_machine(struct work_struc
+ 		/* If AN is done, we're running */
+ 		if (err > 0) {
+ 			phydev->state = PHY_RUNNING;
+-			netif_carrier_on(phydev->attached_dev);
+-			phydev->adjust_link(phydev->attached_dev);
+-
++			phy_link_up(phydev);
+ 		} else if (0 == phydev->link_timeout--)
+ 			needs_aneg = true;
+ 		break;
+@@ -930,8 +937,7 @@ void phy_state_machine(struct work_struc
+ 				}
+ 			}
+ 			phydev->state = PHY_RUNNING;
+-			netif_carrier_on(phydev->attached_dev);
+-			phydev->adjust_link(phydev->attached_dev);
++			phy_link_up(phydev);
+ 		}
+ 		break;
+ 	case PHY_FORCING:
+@@ -941,13 +947,12 @@ void phy_state_machine(struct work_struc
+ 
+ 		if (phydev->link) {
+ 			phydev->state = PHY_RUNNING;
+-			netif_carrier_on(phydev->attached_dev);
++			phy_link_up(phydev);
+ 		} else {
+ 			if (0 == phydev->link_timeout--)
+ 				needs_aneg = true;
++			phy_link_down(phydev, false);
+ 		}
+-
+-		phydev->adjust_link(phydev->attached_dev);
+ 		break;
+ 	case PHY_RUNNING:
+ 		/* Only register a CHANGE if we are polling or ignoring
+@@ -970,14 +975,12 @@ void phy_state_machine(struct work_struc
+ 
+ 		if (phydev->link) {
+ 			phydev->state = PHY_RUNNING;
+-			netif_carrier_on(phydev->attached_dev);
++			phy_link_up(phydev);
+ 		} else {
+ 			phydev->state = PHY_NOLINK;
+-			netif_carrier_off(phydev->attached_dev);
++			phy_link_down(phydev, true);
+ 		}
+ 
+-		phydev->adjust_link(phydev->attached_dev);
+-
+ 		if (phy_interrupt_is_valid(phydev))
+ 			err = phy_config_interrupt(phydev,
+ 						   PHY_INTERRUPT_ENABLED);
+@@ -985,8 +988,7 @@ void phy_state_machine(struct work_struc
+ 	case PHY_HALTED:
+ 		if (phydev->link) {
+ 			phydev->link = 0;
+-			netif_carrier_off(phydev->attached_dev);
+-			phydev->adjust_link(phydev->attached_dev);
++			phy_link_down(phydev, true);
+ 			do_suspend = true;
+ 		}
+ 		break;
+@@ -1006,11 +1008,11 @@ void phy_state_machine(struct work_struc
+ 
+ 				if (phydev->link) {
+ 					phydev->state = PHY_RUNNING;
+-					netif_carrier_on(phydev->attached_dev);
++					phy_link_up(phydev);
+ 				} else	{
+ 					phydev->state = PHY_NOLINK;
++					phy_link_down(phydev, false);
+ 				}
+-				phydev->adjust_link(phydev->attached_dev);
+ 			} else {
+ 				phydev->state = PHY_AN;
+ 				phydev->link_timeout = PHY_AN_TIMEOUT;
+@@ -1022,11 +1024,11 @@ void phy_state_machine(struct work_struc
+ 
+ 			if (phydev->link) {
+ 				phydev->state = PHY_RUNNING;
+-				netif_carrier_on(phydev->attached_dev);
++				phy_link_up(phydev);
+ 			} else	{
+ 				phydev->state = PHY_NOLINK;
++				phy_link_down(phydev, false);
+ 			}
+-			phydev->adjust_link(phydev->attached_dev);
+ 		}
+ 		break;
+ 	}
+--- a/drivers/net/phy/phy_device.c
++++ b/drivers/net/phy/phy_device.c
+@@ -441,6 +441,19 @@ struct phy_device *phy_find_first(struct
+ }
+ EXPORT_SYMBOL(phy_find_first);
+ 
++static void phy_link_change(struct phy_device *phydev, bool up, bool do_carrier)
++{
++	struct net_device *netdev = phydev->attached_dev;
++
++	if (do_carrier) {
++		if (up)
++			netif_carrier_on(netdev);
++		else
++			netif_carrier_off(netdev);
++	}
++	phydev->adjust_link(netdev);
++}
++
+ /**
+  * phy_prepare_link - prepares the PHY layer to monitor link status
+  * @phydev: target phy_device struct
+@@ -659,6 +672,7 @@ int phy_attach_direct(struct net_device
+ 		goto error;
+ 	}
+ 
++	phydev->phy_link_change = phy_link_change;
+ 	phydev->attached_dev = dev;
+ 	dev->phydev = phydev;
+ 
+--- a/include/linux/phy.h
++++ b/include/linux/phy.h
+@@ -433,6 +433,7 @@ struct phy_device {
+ 
+ 	u8 mdix;
+ 
++	void (*phy_link_change)(struct phy_device *, bool up, bool do_carrier);
+ 	void (*adjust_link)(struct net_device *dev);
+ };
+ #define to_phy_device(d) container_of(d, struct phy_device, dev)