ACPICA: Add table-driven dispatch for sleep/wake functions

Simplifies the code, especially the compile-time
ACPI_REDUCED_HARDWARE option.

Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

2 files changed, 88 insertions, 54 deletions

diff --git a/drivers/acpi/acpica/acmacros.h b/drivers/acpi/acpica/acmacros.h
index ef338a96f5b2..f119f473f71a 100644
--- a/drivers/acpi/acpica/acmacros.h
+++ b/drivers/acpi/acpica/acmacros.h
@@ -516,6 +516,12 @@
 
 #endif                          /* ACPI_DEBUG_OUTPUT */
 
+#if (!ACPI_REDUCED_HARDWARE)
+#define ACPI_HW_OPTIONAL_FUNCTION(addr)     addr
+#else
+#define ACPI_HW_OPTIONAL_FUNCTION(addr)     NULL
+#endif
+
 /*
  * Some code only gets executed when the debugger is built in.
  * Note that this is entirely independent of whether the
diff --git a/drivers/acpi/acpica/hwxfsleep.c b/drivers/acpi/acpica/hwxfsleep.c
index ff2055804809..b711f97c9a87 100644
--- a/drivers/acpi/acpica/hwxfsleep.c
+++ b/drivers/acpi/acpica/hwxfsleep.c
@@ -48,6 +48,34 @@
 #define _COMPONENT          ACPI_HARDWARE
 ACPI_MODULE_NAME("hwxfsleep")
 
+/* Local prototypes */
+static acpi_status acpi_hw_sleep_dispatch(u8 sleep_state, u32 function_id);
+
+/*
+ * Dispatch table used to efficiently branch to the various sleep
+ * functions.
+ */
+#define ACPI_SLEEP_FUNCTION         0
+#define ACPI_WAKE_PREP_FUNCTION     1
+#define ACPI_WAKE_FUNCTION          2
+
+/* Legacy functions are optional, based upon ACPI_REDUCED_HARDWARE */
+
+static struct acpi_sleep_functions acpi_sleep_dispatch[] = {
+        {ACPI_HW_OPTIONAL_FUNCTION(acpi_hw_legacy_sleep),
+         acpi_hw_extended_sleep},
+        {ACPI_HW_OPTIONAL_FUNCTION(acpi_hw_legacy_wake_prep),
+         acpi_hw_extended_wake_prep},
+        {ACPI_HW_OPTIONAL_FUNCTION(acpi_hw_legacy_wake), acpi_hw_extended_wake}
+};
+
+/*
+ * These functions are removed for the ACPI_REDUCED_HARDWARE case:
+ *      acpi_set_firmware_waking_vector
+ *      acpi_set_firmware_waking_vector64
+ *      acpi_enter_sleep_state_s4bios
+ */
+
 #if (!ACPI_REDUCED_HARDWARE)
 /*******************************************************************************
  *
@@ -61,6 +89,7 @@ ACPI_MODULE_NAME("hwxfsleep")
  * DESCRIPTION: Sets the 32-bit firmware_waking_vector field of the FACS
  *
  ******************************************************************************/
+
 acpi_status acpi_set_firmware_waking_vector(u32 physical_address)
 {
         ACPI_FUNCTION_TRACE(acpi_set_firmware_waking_vector);
@@ -193,18 +222,65 @@ ACPI_EXPORT_SYMBOL(acpi_enter_sleep_state_s4bios)
 #endif                          /* !ACPI_REDUCED_HARDWARE */
 /*******************************************************************************
  *
+ * FUNCTION:    acpi_hw_sleep_dispatch
+ *
+ * PARAMETERS:  sleep_state         - Which sleep state to enter/exit
+ *              function_id         - Sleep, wake_prep, or Wake
+ *
+ * RETURN:      Status from the invoked sleep handling function.
+ *
+ * DESCRIPTION: Dispatch a sleep/wake request to the appropriate handling
+ *              function.
+ *
+ ******************************************************************************/
+static acpi_status acpi_hw_sleep_dispatch(u8 sleep_state, u32 function_id)
+{
+        acpi_status status;
+        struct acpi_sleep_functions *sleep_functions =
+            &acpi_sleep_dispatch[function_id];
+
+#if (!ACPI_REDUCED_HARDWARE)
+
+        /*
+         * If the Hardware Reduced flag is set (from the FADT), we must
+         * use the extended sleep registers
+         */
+        if (acpi_gbl_reduced_hardware || acpi_gbl_FADT.sleep_control.address) {
+                status = sleep_functions->extended_function(sleep_state);
+        } else {
+                /* Legacy sleep */
+
+                status = sleep_functions->legacy_function(sleep_state);
+        }
+
+        return (status);
+
+#else
+        /*
+         * For the case where reduced-hardware-only code is being generated,
+         * we know that only the extended sleep registers are available
+         */
+        status = sleep_functions->extended_function(sleep_state);
+        return (status);
+
+#endif                          /* !ACPI_REDUCED_HARDWARE */
+}
+
+/*******************************************************************************
+ *
  * FUNCTION:    acpi_enter_sleep_state_prep
  *
  * PARAMETERS:  sleep_state         - Which sleep state to enter
  *
  * RETURN:      Status
  *
- * DESCRIPTION: Prepare to enter a system sleep state (see ACPI 2.0 spec p 231)
+ * DESCRIPTION: Prepare to enter a system sleep state.
  *              This function must execute with interrupts enabled.
  *              We break sleeping into 2 stages so that OSPM can handle
  *              various OS-specific tasks between the two steps.
  *
  ******************************************************************************/
+
 acpi_status acpi_enter_sleep_state_prep(u8 sleep_state)
 {
         acpi_status status;
@@ -291,23 +367,8 @@ acpi_status asmlinkage acpi_enter_sleep_state(u8 sleep_state)
                             acpi_gbl_sleep_type_a, acpi_gbl_sleep_type_b));
                 return_ACPI_STATUS(AE_AML_OPERAND_VALUE);
         }
-#if (!ACPI_REDUCED_HARDWARE)
-
-        /* If Hardware Reduced flag is set, must use the extended sleep registers */
-
-        if (acpi_gbl_reduced_hardware || acpi_gbl_FADT.sleep_control.address) {
-                status = acpi_hw_extended_sleep(sleep_state);
-        } else {
-                /* Legacy sleep */
-
-                status = acpi_hw_legacy_sleep(sleep_state);
-        }
-
-#else
-        status = acpi_hw_extended_sleep(sleep_state);
-
-#endif                          /* !ACPI_REDUCED_HARDWARE */
 
+        status = acpi_hw_sleep_dispatch(sleep_state, ACPI_SLEEP_FUNCTION);
         return_ACPI_STATUS(status);
 }
 
@@ -330,26 +391,9 @@ acpi_status acpi_leave_sleep_state_prep(u8 sleep_state)
 {
         acpi_status status;
 
-        ACPI_FUNCTION_TRACE(acpi_leave_sleep_state);
-
-
-#if (!ACPI_REDUCED_HARDWARE)
-
-        /* If Hardware Reduced flag is set, must use the extended sleep registers */
-
-        if (acpi_gbl_reduced_hardware || acpi_gbl_FADT.sleep_control.address) {
-                status = acpi_hw_extended_wake_prep(sleep_state);
-        } else {
-                /* Legacy sleep */
-
-                status = acpi_hw_legacy_wake_prep(sleep_state);
-        }
-#else
-        status = acpi_hw_extended_wake_prep(sleep_state);
-
-#endif                          /* !ACPI_REDUCED_HARDWARE */
-
+        ACPI_FUNCTION_TRACE(acpi_leave_sleep_state_prep);
 
+        status = acpi_hw_sleep_dispatch(sleep_state, ACPI_WAKE_PREP_FUNCTION);
         return_ACPI_STATUS(status);
 }
 
@@ -359,7 +403,7 @@ ACPI_EXPORT_SYMBOL(acpi_leave_sleep_state_prep)
  *
  * FUNCTION:    acpi_leave_sleep_state
  *
- * PARAMETERS:  sleep_state         - Which sleep state we just exited
+ * PARAMETERS:  sleep_state         - Which sleep state we are exiting
  *
  * RETURN:      Status
  *
@@ -374,23 +418,7 @@ acpi_status acpi_leave_sleep_state(u8 sleep_state)
         ACPI_FUNCTION_TRACE(acpi_leave_sleep_state);
 
 
-#if (!ACPI_REDUCED_HARDWARE)
-
-        /* If Hardware Reduced flag is set, must use the extended sleep registers */
-
-        if (acpi_gbl_reduced_hardware || acpi_gbl_FADT.sleep_control.address) {
-                status = acpi_hw_extended_wake(sleep_state);
-        } else {
-                /* Legacy sleep */
-
-                status = acpi_hw_legacy_wake(sleep_state);
-        }
-
-#else
-        status = acpi_hw_extended_wake(sleep_state);
-
-#endif                          /* !ACPI_REDUCED_HARDWARE */
-
+        status = acpi_hw_sleep_dispatch(sleep_state, ACPI_WAKE_FUNCTION);
         return_ACPI_STATUS(status);
 }