From: Russell King <rmk+kernel@armlinux.org.uk>
Date: Sun, 10 Nov 2019 14:06:28 +0000
Subject: net: sfp: handle module remove outside state machine
Patch-mainline: v5.5-rc1
Git-commit: d2e816c0293fc263b3f168c14992a5f1a50d7593
References: bsc#1154353

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>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 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
@@ -1502,6 +1502,14 @@ 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) {
@@ -1511,9 +1519,7 @@ 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)
@@ -1535,10 +1541,6 @@ 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;
 	}
 }