2 files changed, 45 insertions, 0 deletions

diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index bbe48ad20886..4d6eeb1793e6 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -23,6 +23,7 @@
 #include <linux/io.h>
 #include <linux/nd.h>
 #include <asm/cacheflush.h>
+#include <acpi/nfit.h>
 #include "nfit.h"
 
 /*
@@ -690,6 +691,32 @@ static bool add_memdev(struct acpi_nfit_desc *acpi_desc,
         return true;
 }
 
+int nfit_get_smbios_id(u32 device_handle, u16 *flags)
+{
+        struct acpi_nfit_memory_map *memdev;
+        struct acpi_nfit_desc *acpi_desc;
+        struct nfit_mem *nfit_mem;
+
+        mutex_lock(&acpi_desc_lock);
+        list_for_each_entry(acpi_desc, &acpi_descs, list) {
+                mutex_lock(&acpi_desc->init_mutex);
+                list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) {
+                        memdev = __to_nfit_memdev(nfit_mem);
+                        if (memdev->device_handle == device_handle) {
+                                mutex_unlock(&acpi_desc->init_mutex);
+                                mutex_unlock(&acpi_desc_lock);
+                                *flags = memdev->flags;
+                                return memdev->physical_id;
+                        }
+                }
+                mutex_unlock(&acpi_desc->init_mutex);
+        }
+        mutex_unlock(&acpi_desc_lock);
+
+        return -ENODEV;
+}
+EXPORT_SYMBOL_GPL(nfit_get_smbios_id);
+
 /*
  * An implementation may provide a truncated control region if no block windows
  * are defined.
diff --git a/include/acpi/nfit.h b/include/acpi/nfit.h
new file mode 100644
index 000000000000..86ed07c1200d
--- /dev/null
+++ b/include/acpi/nfit.h
@@ -0,0 +1,18 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0
+ * Copyright (C) 2018 Intel Corporation
+ */
+
+#ifndef __ACPI_NFIT_H
+#define __ACPI_NFIT_H
+
+#if IS_ENABLED(CONFIG_ACPI_NFIT)
+int nfit_get_smbios_id(u32 device_handle, u16 *flags);
+#else
+static inline int nfit_get_smbios_id(u32 device_handle, u16 *flags)
+{
+        return -EOPNOTSUPP;
+}
+#endif
+
+#endif /* __ACPI_NFIT_H */