[PATCH 1/2] efi: add a function for transferring status to string

["Lee, Chun-Yi" <joeyli.kernel@gmail.com>]

This function can be used to transfer EFI status code to string
to improve the readability of debug log.

Signed-off-by: "Lee, Chun-Yi" <jlee@suse.com>
---
 include/linux/efi.h | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)

diff --git a/include/linux/efi.h b/include/linux/efi.h
index d87acf62958e..08daf4cdd807 100644
--- a/include/linux/efi.h
+++ b/include/linux/efi.h
@@ -42,6 +42,32 @@
 #define EFI_ABORTED		(21 | (1UL << (BITS_PER_LONG-1)))
 #define EFI_SECURITY_VIOLATION	(26 | (1UL << (BITS_PER_LONG-1)))
 
+#define EFI_STATUS_STR(_status) \
+	case EFI_##_status: \
+		return "EFI_" __stringify(_status);
+
+static inline char *
+efi_status_to_str(unsigned long status)
+{
+	switch (status) {
+	EFI_STATUS_STR(SUCCESS)
+	EFI_STATUS_STR(LOAD_ERROR)
+	EFI_STATUS_STR(INVALID_PARAMETER)
+	EFI_STATUS_STR(UNSUPPORTED)
+	EFI_STATUS_STR(BAD_BUFFER_SIZE)
+	EFI_STATUS_STR(BUFFER_TOO_SMALL)
+	EFI_STATUS_STR(NOT_READY)
+	EFI_STATUS_STR(DEVICE_ERROR)
+	EFI_STATUS_STR(WRITE_PROTECTED)
+	EFI_STATUS_STR(OUT_OF_RESOURCES)
+	EFI_STATUS_STR(NOT_FOUND)
+	EFI_STATUS_STR(ABORTED)
+	EFI_STATUS_STR(SECURITY_VIOLATION)
+	}
+
+	return "";
+}
+
 typedef unsigned long efi_status_t;
 typedef u8 efi_bool_t;
 typedef u16 efi_char16_t;		/* UNICODE character */
-- 
2.16.4