static int acpi_processor_get_throttling(struct acpi_processor *pr);
 int acpi_processor_set_throttling(struct acpi_processor *pr, int state);
 
+/*
+ * _TPC - Throttling Present Capabilities
+ */
 static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
 {
        acpi_status status = 0;
        if (!pr)
                return -EINVAL;
        status = acpi_evaluate_integer(pr->handle, "_TPC", NULL, &tpc);
-       if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
-               ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
+       if (ACPI_FAILURE(status)) {
+               if (status != AE_NOT_FOUND) {
+                       ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TPC"));
+               }
                return -ENODEV;
        }
        pr->throttling_platform_limit = (int)tpc;
        return acpi_processor_get_platform_limit(pr);
 }
 
-/* --------------------------------------------------------------------------
-                             _PTC, _TSS, _TSD support 
-   -------------------------------------------------------------------------- */
+/*
+ * _PTC - Processor Throttling Control (and status) register location
+ */
 static int acpi_processor_get_throttling_control(struct acpi_processor *pr)
 {
        int result = 0;
 
        status = acpi_evaluate_object(pr->handle, "_PTC", NULL, &buffer);
        if (ACPI_FAILURE(status)) {
-               ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
+               if (status != AE_NOT_FOUND) {
+                       ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PTC"));
+               }
                return -ENODEV;
        }
 
 
        return result;
 }
+
+/*
+ * _TSS - Throttling Supported States
+ */
 static int acpi_processor_get_throttling_states(struct acpi_processor *pr)
 {
        int result = 0;
 
        status = acpi_evaluate_object(pr->handle, "_TSS", NULL, &buffer);
        if (ACPI_FAILURE(status)) {
-               ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
+               if (status != AE_NOT_FOUND) {
+                       ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSS"));
+               }
                return -ENODEV;
        }
 
 
        return result;
 }
+
+/*
+ * _TSD - T-State Dependencies
+ */
 static int acpi_processor_get_tsd(struct acpi_processor *pr)
 {
        int result = 0;
 
        status = acpi_evaluate_object(pr->handle, "_TSD", NULL, &buffer);
        if (ACPI_FAILURE(status)) {
+               if (status != AE_NOT_FOUND) {
+                       ACPI_EXCEPTION((AE_INFO, status, "Evaluating _TSD"));
+               }
                return -ENODEV;
        }
 
        int result = 0;
        int step = 0;
        int i = 0;
-       int no_ptc = 0;
-       int no_tss = 0;
-       int no_tsd = 0;
 
        ACPI_DEBUG_PRINT((ACPI_DB_INFO,
                          "pblk_address[0x%08x] duty_offset[%d] duty_width[%d]\n",
        if (!pr)
                return -EINVAL;
 
-       /* TBD: Support ACPI 2.0 objects */
-       no_ptc = acpi_processor_get_throttling_control(pr);
-       no_tss = acpi_processor_get_throttling_states(pr);
-       no_tsd = acpi_processor_get_tsd(pr);
-
-       if (no_ptc || no_tss) {
+       /*
+        * Evaluate _PTC, _TSS and _TPC
+        * They must all be present or none of them can be used.
+        */
+       if (acpi_processor_get_throttling_control(pr) ||
+               acpi_processor_get_throttling_states(pr) ||
+               acpi_processor_get_platform_limit(pr))
+       {
                pr->throttling.acpi_processor_get_throttling =
                    &acpi_processor_get_throttling_fadt;
                pr->throttling.acpi_processor_set_throttling =
                    &acpi_processor_set_throttling_ptc;
        }
 
+       acpi_processor_get_tsd(pr);
+
        if (!pr->throttling.address) {
                ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No throttling register\n"));
                return 0;