From abf92e78e39956128d652ac229ba99e706293c0d Mon Sep 17 00:00:00 2001
From: Tim Crawford <tcrawford@system76.com>
Date: Mon, 11 Jan 2021 12:34:42 -0700
Subject: [PATCH] Do not access NV device if not present

Prevents NULL pointer dereference on pang10 when removing module.
---
 system76_nv_hda.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/system76_nv_hda.c b/system76_nv_hda.c
index 73a8c9f..7c2de34 100644
--- a/system76_nv_hda.c
+++ b/system76_nv_hda.c
@@ -162,6 +162,9 @@ static int __init nv_hda_init(struct device *dev) {
 }
 
 static void __exit nv_hda_exit(void) {
+    if (dis_dev == NULL)
+        return;
+
     dis_dev_get();
 
     nv_hda_off();