1 files changed, 18 insertions, 16 deletions

diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c
index f12dcd1dc208..0260b14c8d94 100644
--- a/drivers/pci/pci-label.c
+++ b/drivers/pci/pci-label.c
@@ -187,7 +187,6 @@ static const char device_label_dsm_uuid[] = {
 };
 
 enum acpi_attr_enum {
-        ACPI_ATTR_NONE = 0,
         ACPI_ATTR_LABEL_SHOW,
         ACPI_ATTR_INDEX_SHOW,
 };
@@ -222,20 +221,16 @@ dsm_get_label(struct device *dev, char *buf, enum acpi_attr_enum attr)
         if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 2 &&
             tmp[0].type == ACPI_TYPE_INTEGER &&
             tmp[1].type == ACPI_TYPE_STRING) {
-                len = tmp[0].integer.value;
-                if (buf) {
-                        /*
-                         * This second string element is optional even when
-                         * this _DSM is implemented; when not implemented,
-                         * this entry must return a null string.
-                         */
-                        if (attr == ACPI_ATTR_INDEX_SHOW)
-                                scnprintf(buf, PAGE_SIZE, "%llu\n",
-                                tmp->integer.value);
-                        else if (attr == ACPI_ATTR_LABEL_SHOW)
-                                dsm_label_utf16s_to_utf8s(tmp + 1, buf);
-                        len = strlen(buf) > 0 ? strlen(buf) : -1;
-                }
+                /*
+                 * The second string element is optional even when
+                 * this _DSM is implemented; when not implemented,
+                 * this entry must return a null string.
+                 */
+                if (attr == ACPI_ATTR_INDEX_SHOW)
+                        scnprintf(buf, PAGE_SIZE, "%llu\n", tmp->integer.value);
+                else if (attr == ACPI_ATTR_LABEL_SHOW)
+                        dsm_label_utf16s_to_utf8s(tmp + 1, buf);
+                len = strlen(buf) > 0 ? strlen(buf) : -1;
         }
 
         ACPI_FREE(obj);
@@ -246,7 +241,14 @@ dsm_get_label(struct device *dev, char *buf, enum acpi_attr_enum attr)
 static bool
 device_has_dsm(struct device *dev)
 {
-        return dsm_get_label(dev, NULL, ACPI_ATTR_NONE) > 0;
+        acpi_handle handle;
+
+        handle = ACPI_HANDLE(dev);
+        if (!handle)
+                return false;
+
+        return !!acpi_check_dsm(handle, device_label_dsm_uuid, 0x2,
+                                1 << DEVICE_LABEL_DSM);
 }
 
 static umode_t