[PATCH v9 07/21] ACPI / sleep: Introduce arm64 specific acpi_sleep.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
management, so introduce acpi_sleep.c to allow other drivers to function
until S states are defined.

Since it is arm64 specific stub holder, so let acpi_sleep.c to ARM64
specific.

TODO: merge this with drivers/acpi/sleep.c once we fix the specification.

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>
Tested-by: Robert Richter <rrichter at cavium.com>
Acked-by: Robert Richter <rrichter at cavium.com>
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>
---
 arch/arm64/kernel/Makefile     |  2 +-
 arch/arm64/kernel/acpi_sleep.c | 28 ++++++++++++++++++++++++++++
 drivers/acpi/Makefile          |  2 ++
 3 files changed, 31 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm64/kernel/acpi_sleep.c

diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index 218eb7e..4435943 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -34,7 +34,7 @@ arm64-obj-$(CONFIG_KGDB)		+= kgdb.o
 arm64-obj-$(CONFIG_EFI)			+= efi.o efi-stub.o efi-entry.o
 arm64-obj-$(CONFIG_PCI)			+= pci.o
 arm64-obj-$(CONFIG_ARMV8_DEPRECATED)	+= armv8_deprecated.o
-arm64-obj-$(CONFIG_ACPI)		+= acpi.o
+arm64-obj-$(CONFIG_ACPI)		+= acpi.o acpi_sleep.o
 
 obj-y					+= $(arm64-obj-y) vdso/
 obj-m					+= $(arm64-obj-m)
diff --git a/arch/arm64/kernel/acpi_sleep.c b/arch/arm64/kernel/acpi_sleep.c
new file mode 100644
index 0000000..54578ef
--- /dev/null
+++ b/arch/arm64/kernel/acpi_sleep.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;
+}
diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
index 623b117..c32edf5 100644
--- a/drivers/acpi/Makefile
+++ b/drivers/acpi/Makefile
@@ -23,7 +23,9 @@ acpi-y				+= nvs.o
 
 # Power management related files
 acpi-y				+= wakeup.o
+ifneq (,$(findstring $(ARCH),x86 ia64))
 acpi-y				+= sleep.o
+endif
 acpi-y				+= device_pm.o
 acpi-$(CONFIG_ACPI_SLEEP)	+= proc.o
 
-- 
1.9.1