[PATCH v8 05/21] ACPI / sleep: Introduce sleep_arm.c

[Hanjun Guo]

From: Graeme Gregory <graeme.gregory at linaro.org>

ACPI 5.1 does not currently support S states for ARM64 hardware but
ACPI code will call acpi_target_system_state() for device power
managment, so introduce sleep_arm.c to allow other drivers to function
until S states are defined.

CC: Rafael J. Wysocki <rjw at rjwysocki.net>
Tested-by: Suravee Suthikulpanit <Suravee.Suthikulpanit at amd.com>
Tested-by: Yijing Wang <wangyijing at huawei.com>
Tested-by: Mark Langsdorf <mlangsdo at redhat.com>
Tested-by: Jon Masters <jcm at redhat.com>
Tested-by: Timur Tabi <timur at codeaurora.org>
Signed-off-by: Graeme Gregory <graeme.gregory at linaro.org>
Signed-off-by: Tomasz Nowicki <tomasz.nowicki at linaro.org>
Signed-off-by: Hanjun Guo <hanjun.guo at linaro.org>
---
 drivers/acpi/Makefile    |  4 ++++
 drivers/acpi/sleep_arm.c | 28 ++++++++++++++++++++++++++++
 2 files changed, 32 insertions(+)
 create mode 100644 drivers/acpi/sleep_arm.c

diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index f74317c..bcec54e 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -23,7 +23,11 @@ acpi-y				+= nvs.o
 
 # Power management related files
 acpi-y				+= wakeup.o
+ifeq ($(ARCH), arm64)
+acpi-y				+= sleep_arm.o
+else # X86, IA64
 acpi-y				+= sleep.o
+endif
 acpi-y				+= device_pm.o
 acpi-$(CONFIG_ACPI_SLEEP)	+= proc.o
 
diff --git a/drivers/acpi/sleep_arm.c b/drivers/acpi/sleep_arm.c
new file mode 100644
index 0000000..54578ef
--- /dev/null
+++ b/drivers/acpi/sleep_arm.c
@@ -0,0 +1,28 @@
+/*
+ *  ARM64 Specific Sleep Functionality
+ *
+ *  Copyright (C) 2013-2014, Linaro Ltd.
+ *      Author: Graeme Gregory <graeme.gregory at linaro.org>
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License version 2 as
+ *  published by the Free Software Foundation.
+ */
+
+#include <linux/acpi.h>
+
+/*
+ * Currently the ACPI 5.1 standard does not define S states in a
+ * manner which is usable for ARM64. These two stubs are sufficient
+ * that system initialises and device PM works.
+ */
+u32 acpi_target_system_state(void)
+{
+	return ACPI_STATE_S0;
+}
+EXPORT_SYMBOL_GPL(acpi_target_system_state);
+
+int __init acpi_sleep_init(void)
+{
+	return -ENOSYS;
+}
-- 
1.9.1