diff --git a/include/fs/fs.h b/include/fs/fs.h
index 06543a700da..48bb13495aa 100644
--- a/include/fs/fs.h
+++ b/include/fs/fs.h
@@ -416,7 +416,9 @@ int fs_mount(struct fs_mount_t *mp);
  * @param mp Pointer to the fs_mount_t structure
  *
  * @retval 0 on success;
- * @retval <0 negative errno code on error.
+ * @retval -EINVAL if no system has been mounted at given mount point;
+ * @retval -ENOTSUP when not supported by underlying file system driver;
+ * @retval <0 an other negative errno code on error.
  */
 int fs_unmount(struct fs_mount_t *mp);
 
diff --git a/subsys/fs/fs.c b/subsys/fs/fs.c
index 4854d80fedf..6e6635d6bd3 100644
--- a/subsys/fs/fs.c
+++ b/subsys/fs/fs.c
@@ -657,16 +657,21 @@ int fs_unmount(struct fs_mount_t *mp)
 {
 	int rc = -EINVAL;
 
-	if ((mp == NULL) || (mp->mnt_point == NULL) ||
-				(strlen(mp->mnt_point) <= 1)) {
-		LOG_ERR("invalid mount point!!");
-		return -EINVAL;
+	if (mp == NULL) {
+		return rc;
 	}
 
 	k_mutex_lock(&mutex, K_FOREVER);
-	if ((mp->fs == NULL) || mp->fs->unmount == NULL) {
-		LOG_ERR("fs ops functions not set!!");
-		rc = -EINVAL;
+
+	if (mp->fs == NULL) {
+		LOG_ERR("fs not mounted (mp == %p)", mp);
+		goto unmount_err;
+	}
+
+	if (mp->fs->unmount == NULL) {
+		LOG_ERR("mount path %s is not unmountable",
+			log_strdup(mp->mnt_point));
+		rc = -ENOTSUP;
 		goto unmount_err;
 	}
 
diff --git a/tests/subsys/fs/fs_api/src/test_fs_dir_file.c b/tests/subsys/fs/fs_api/src/test_fs_dir_file.c
index 5b83870f24e..99e379ec864 100644
--- a/tests/subsys/fs/fs_api/src/test_fs_dir_file.c
+++ b/tests/subsys/fs/fs_api/src/test_fs_dir_file.c
@@ -119,7 +119,7 @@ void test_unmount(void)
 
 	TC_PRINT("\nunmount file system that has never been mounted:\n");
 	ret = fs_unmount(&test_fs_mnt_unsupported_fs);
-	zassert_not_equal(ret, 0, "Unmount a never mounted fs");
+	zassert_equal(ret, -EINVAL, "Unmount a never mounted fs");
 
 	TC_PRINT("\nunmount file system multiple times:\n");
 	ret = fs_unmount(&test_fs_mnt_1);
@@ -127,7 +127,7 @@ void test_unmount(void)
 
 	test_fs_mnt_1.fs = &temp_fs;
 	ret = fs_unmount(&test_fs_mnt_1);
-	zassert_not_equal(ret, 0, "Unmount a unmounted fs");
+	zassert_equal(ret, -EINVAL, "Unmount a unmounted fs");
 }
 
 /**