From 089b2bec97bbddb519e849a58b1ba8cc9880a4e5 Mon Sep 17 00:00:00 2001
From: Erik Schmauss <erik.schmauss@intel.com>
Date: Fri, 10 Aug 2018 14:42:57 -0700
Subject: [PATCH] ACPICA: Utilities: split hex detection into smaller functions

acpi_ut_implicit_strtoul64() called acpi_ut_detect_hex_prefix() and
ignored the return value. Instead, use acpi_ut_remove_hex_prefix().

Signed-off-by: Erik Schmauss <erik.schmauss@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---
 drivers/acpi/acpica/acutils.h     |  2 ++
 drivers/acpi/acpica/utstrsuppt.c  | 28 ++++++++++++++++++++++++----
 drivers/acpi/acpica/utstrtoul64.c |  2 +-
 3 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/drivers/acpi/acpica/acutils.h b/drivers/acpi/acpica/acutils.h
index 2733cd4e418c..3374d41582b5 100644
--- a/drivers/acpi/acpica/acutils.h
+++ b/drivers/acpi/acpica/acutils.h
@@ -180,6 +180,8 @@ char acpi_ut_remove_leading_zeros(char **string);
 
 u8 acpi_ut_detect_hex_prefix(char **string);
 
+void acpi_ut_remove_hex_prefix(char **string);
+
 u8 acpi_ut_detect_octal_prefix(char **string);
 
 /*
diff --git a/drivers/acpi/acpica/utstrsuppt.c b/drivers/acpi/acpica/utstrsuppt.c
index 954f8e3e35cd..05ff20049b87 100644
--- a/drivers/acpi/acpica/utstrsuppt.c
+++ b/drivers/acpi/acpica/utstrsuppt.c
@@ -231,16 +231,36 @@ char acpi_ut_remove_whitespace(char **string)
 
 u8 acpi_ut_detect_hex_prefix(char **string)
 {
+	char *initial_position = *string;
 
-	if ((**string == ACPI_ASCII_ZERO) &&
-	    (tolower((int)*(*string + 1)) == 'x')) {
-		*string += 2;	/* Go past the leading 0x */
-		return (TRUE);
+	acpi_ut_remove_hex_prefix(string);
+	if (*string != initial_position) {
+		return (TRUE);	/* String is past leading 0x */
 	}
 
 	return (FALSE);		/* Not a hex string */
 }
 
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_remove_hex_prefix
+ *
+ * PARAMETERS:  string                  - Pointer to input ASCII string
+ *
+ * RETURN:      none
+ *
+ * DESCRIPTION: Remove a hex "0x" prefix
+ *
+ ******************************************************************************/
+
+void acpi_ut_remove_hex_prefix(char **string)
+{
+	if ((**string == ACPI_ASCII_ZERO) &&
+	    (tolower((int)*(*string + 1)) == 'x')) {
+		*string += 2;	/* Go past the leading 0x */
+	}
+}
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ut_detect_octal_prefix
diff --git a/drivers/acpi/acpica/utstrtoul64.c b/drivers/acpi/acpica/utstrtoul64.c
index 8fadad242db6..5fde619a8bbd 100644
--- a/drivers/acpi/acpica/utstrtoul64.c
+++ b/drivers/acpi/acpica/utstrtoul64.c
@@ -218,7 +218,7 @@ u64 acpi_ut_implicit_strtoul64(char *string)
 	 * implicit conversions, and the "0x" prefix is "not allowed".
 	 * However, allow a "0x" prefix as an ACPI extension.
 	 */
-	acpi_ut_detect_hex_prefix(&string);
+	acpi_ut_remove_hex_prefix(&string);
 
 	if (!acpi_ut_remove_leading_zeros(&string)) {
 		return_VALUE(0);