openwrt/target/linux/generic/backport-4.19/723-v5.5-net-sfp-handle-module-remove-outside-state-machine.patch

From d2591ea5520e2ee8fa557f96bb64c23cafac4b20 Mon Sep 17 00:00:00 2001
From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Tue, 15 Oct 2019 10:33:13 +0100
Subject: [PATCH 621/660] net: sfp: handle module remove outside state machine

Removing a module resets the module state machine back to its initial
state.  Rather than explicitly handling this in every state, handle it
early on outside of the state machine.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
---
 drivers/net/phy/sfp.c | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

--- a/drivers/net/phy/sfp.c
+++ b/drivers/net/phy/sfp.c
@@ -1500,6 +1500,14 @@ static void sfp_sm_device(struct sfp *sf
  */
 static void sfp_sm_module(struct sfp *sfp, unsigned int event)
 {
+	/* Handle remove event globally, it resets this state machine */
+	if (event == SFP_E_REMOVE) {
+		if (sfp->sm_mod_state > SFP_MOD_PROBE)
+			sfp_sm_mod_remove(sfp);
+		sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
+		return;
+	}
+
 	switch (sfp->sm_mod_state) {
 	default:
 		if (event == SFP_E_INSERT && sfp->attached) {
@@ -1509,9 +1517,7 @@ static void sfp_sm_module(struct sfp *sf
 		break;
 
 	case SFP_MOD_PROBE:
-		if (event == SFP_E_REMOVE) {
-			sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
-		} else if (event == SFP_E_TIMEOUT) {
+		if (event == SFP_E_TIMEOUT) {
 			int val = sfp_sm_mod_probe(sfp);
 
 			if (val == 0)
@@ -1533,10 +1539,6 @@ static void sfp_sm_module(struct sfp *sf
 		/* fallthrough */
 	case SFP_MOD_PRESENT:
 	case SFP_MOD_ERROR:
-		if (event == SFP_E_REMOVE) {
-			sfp_sm_mod_remove(sfp);
-			sfp_sm_mod_next(sfp, SFP_MOD_EMPTY, 0);
-		}
 		break;
 	}
 }