From 8c751e0d9a5264376935a84429a2d468c8877d99 Mon Sep 17 00:00:00 2001
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: Sun, 20 Feb 2022 15:15:17 +0000
Subject: [PATCH] nvmem: core: Check input parameter for NULL in
 nvmem_unregister()
Git-commit: 8c751e0d9a5264376935a84429a2d468c8877d99
References: bsc#1204241
Patch-mainline: v5.18-rc1

nvmem_unregister() frees resources and standard pattern is to allow
caller to not care if it's NULL or not. This will reduce burden on
the callers to perform this check.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20220220151527.17216-4-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/nvmem/core.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/nvmem/core.c
+++ b/drivers/nvmem/core.c
@@ -527,6 +527,8 @@ EXPORT_SYMBOL_GPL(nvmem_register);
  */
 int nvmem_unregister(struct nvmem_device *nvmem)
 {
+	if (!nvmem)
+		return 0;
 	mutex_lock(&nvmem_mutex);
 	if (nvmem->users) {
 		mutex_unlock(&nvmem_mutex);