Merge remote-tracking branch 'remotes/fslc/4.9-2.3.x-imx' into toradex_4.9-2.3.x-imx-nextColibri-iMX7_LXDE-Image_2.8b6.184-20190401Colibri-iMX6_LXDE-Image_2.8b6.184-20190401Colibri-iMX6ULL_LXDE-Image_2.8b6.184-20190401Apalis-iMX6_LXDE-Image_2.8b6.184-20190401

1 files changed, 22 insertions, 0 deletions

diff --git a/drivers/acpi/power.c b/drivers/acpi/power.c
index 3a6c9b741b23..4f4c34892086 100644
--- a/drivers/acpi/power.c
+++ b/drivers/acpi/power.c
@@ -131,6 +131,23 @@ void acpi_power_resources_list_free(struct list_head *list)
 	}
 }
 
+static bool acpi_power_resource_is_dup(union acpi_object *package,
+				       unsigned int start, unsigned int i)
+{
+	acpi_handle rhandle, dup;
+	unsigned int j;
+
+	/* The caller is expected to check the package element types */
+	rhandle = package->package.elements[i].reference.handle;
+	for (j = start; j < i; j++) {
+		dup = package->package.elements[j].reference.handle;
+		if (dup == rhandle)
+			return true;
+	}
+
+	return false;
+}
+
 int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
 				 struct list_head *list)
 {
@@ -150,6 +167,11 @@ int acpi_extract_power_resources(union acpi_object *package, unsigned int start,
 			err = -ENODEV;
 			break;
 		}
+
+		/* Some ACPI tables contain duplicate power resource references */
+		if (acpi_power_resource_is_dup(package, start, i))
+			continue;
+
 		err = acpi_add_power_resource(rhandle);
 		if (err)
 			break;