[openwrt/openwrt] mvebu: add missing patch for reprobing SFP phys for 4.14

[LEDE Commits]

jogo pushed a commit to openwrt/openwrt.git, branch master:
https://git.lede-project.org/c5b06da56cebf5a4373ebeeab2b5a942246fb04d

commit c5b06da56cebf5a4373ebeeab2b5a942246fb04d
Author: Jonas Gorski <jonas.gorski at gmail.com>
AuthorDate: Sun Feb 25 22:54:39 2018 +0100

    mvebu: add missing patch for reprobing SFP phys for 4.14
    
    Add the patch for reprobing phys also for 4.14, as it is still needed.
    
    Fixes: 4ccad922293a ("mvebu: Add support for kernel 4.14")
    Signed-off-by: Jonas Gorski <jonas.gorski at gmail.com>
---
 .../mvebu/patches-4.14/450-reprobe_sfp_phy.patch   | 98 ++++++++++++++++++++++
 1 file changed, 98 insertions(+)

diff --git a/target/linux/mvebu/patches-4.14/450-reprobe_sfp_phy.patch b/target/linux/mvebu/patches-4.14/450-reprobe_sfp_phy.patch
new file mode 100644
index 0000000..a9a6634
--- /dev/null
+++ b/target/linux/mvebu/patches-4.14/450-reprobe_sfp_phy.patch
@@ -0,0 +1,98 @@
+From 28baa5e2635285b178326b301f534ed95c65dd01 Mon Sep 17 00:00:00 2001
+From: Jonas Gorski <jonas.gorski at gmail.com>
+Date: Thu, 29 Sep 2016 11:44:39 +0200
+Subject: [PATCH] sfp: retry phy probe if unsuccessful
+
+Some phys seem to take longer than 50 ms to come out of reset, so retry
+until we find a phy.
+
+Signed-off-by: Jonas Gorski <jonas.gorski at gmail.com>
+---
+ drivers/net/phy/sfp.c | 38 +++++++++++++++++++++++++-------------
+ 1 file changed, 25 insertions(+), 13 deletions(-)
+
+--- a/drivers/net/phy/sfp.c
++++ b/drivers/net/phy/sfp.c
+@@ -488,7 +488,7 @@ static void sfp_sm_phy_detach(struct sfp
+ 	sfp->mod_phy = NULL;
+ }
+ 
+-static void sfp_sm_probe_phy(struct sfp *sfp)
++static int sfp_sm_probe_phy(struct sfp *sfp)
+ {
+ 	struct phy_device *phy;
+ 	int err;
+@@ -497,12 +497,12 @@ static void sfp_sm_probe_phy(struct sfp
+ 
+ 	phy = mdiobus_scan(sfp->i2c_mii, SFP_PHY_ADDR);
+ 	if (IS_ERR(phy)) {
++		if (PTR_ERR(phy) == -ENODEV) {
++			dev_dbg(sfp->dev, "no PHY detected\n");
++			return -EAGAIN;
++		}
+ 		dev_err(sfp->dev, "mdiobus scan returned %ld\n", PTR_ERR(phy));
+-		return;
+-	}
+-	if (!phy) {
+-		dev_info(sfp->dev, "no PHY detected\n");
+-		return;
++		return PTR_ERR(phy);
+ 	}
+ 
+ 	err = sfp_add_phy(sfp->sfp_bus, phy);
+@@ -510,11 +510,13 @@ static void sfp_sm_probe_phy(struct sfp
+ 		phy_device_remove(phy);
+ 		phy_device_free(phy);
+ 		dev_err(sfp->dev, "sfp_add_phy failed: %d\n", err);
+-		return;
++		return err;
+ 	}
+ 
+ 	sfp->mod_phy = phy;
+ 	phy_start(phy);
++
++	return 0;
+ }
+ 
+ static void sfp_sm_link_up(struct sfp *sfp)
+@@ -560,14 +562,9 @@ static void sfp_sm_fault(struct sfp *sfp
+ 
+ static void sfp_sm_mod_init(struct sfp *sfp)
+ {
+-	sfp_module_tx_enable(sfp);
++	int ret = 0;
+ 
+-	/* Wait t_init before indicating that the link is up, provided the
+-	 * current state indicates no TX_FAULT.  If TX_FAULT clears before
+-	 * this time, that's fine too.
+-	 */
+-	sfp_sm_next(sfp, SFP_S_INIT, T_INIT_JIFFIES);
+-	sfp->sm_retries = 5;
++	sfp_module_tx_enable(sfp);
+ 
+ 	/* Setting the serdes link mode is guesswork: there's no
+ 	 * field in the EEPROM which indicates what mode should
+@@ -581,7 +578,22 @@ static void sfp_sm_mod_init(struct sfp *
+ 	if (sfp->id.base.e1000_base_t ||
+ 	    sfp->id.base.e100_base_lx ||
+ 	    sfp->id.base.e100_base_fx)
+-		sfp_sm_probe_phy(sfp);
++		ret = sfp_sm_probe_phy(sfp);
++
++	if (!ret) {
++		/* Wait t_init before indicating that the link is up, provided
++		 * the current state indicates no TX_FAULT.  If TX_FAULT clears
++		 * this time, that's fine too.
++		 */
++		sfp_sm_next(sfp, SFP_S_INIT, T_INIT_JIFFIES);
++		sfp->sm_retries = 5;
++		return;
++	}
++
++	if (ret == -EAGAIN)
++		sfp_sm_set_timer(sfp, T_PROBE_RETRY);
++	else
++		sfp_sm_next(sfp, SFP_S_TX_DISABLE, 0);
+ }
+ 
+ static int sfp_sm_mod_probe(struct sfp *sfp)