On 2015?03?14? 05:49, Rafael J. Wysocki wrote:

On Friday, March 13, 2015 04:14:29 PM Hanjun Guo wrote:

quoted

From: Graeme Gregory <redacted>

ACPI 5.1 does not currently support S states for ARM64 hardware but
ACPI code will call acpi_target_system_state() and acpi_sleep_init()
for device power management, so introduce CONFIG_ACPI_GENERIC_SLEEP
and select it for x86 and ia64 only to make sleep functions available,
and also introduce stub function to allow other drivers to function
until S states are defined for ARM64.

It will be no functional change for x86 and IA64.

CC: Rafael J. Wysocki <redacted>
Suggested-by: Rafael J. Wysocki <redacted>
Acked-by: Robert Richter <redacted>
Acked-by: Lorenzo Pieralisi <redacted>
Signed-off-by: Graeme Gregory <redacted>
Signed-off-by: Tomasz Nowicki <redacted>
Signed-off-by: Hanjun Guo <redacted>
---
  arch/ia64/Kconfig       | 1 +
  arch/x86/Kconfig        | 1 +
  drivers/acpi/Kconfig    | 4 ++++
  drivers/acpi/Makefile   | 2 +-
  drivers/acpi/internal.h | 4 ++++
  5 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/arch/ia64/Kconfig b/arch/ia64/Kconfig
index 074e52b..e8728d7 100644
--- a/arch/ia64/Kconfig
+++ b/arch/ia64/Kconfig

@@ -10,6 +10,7 @@ config IA64
  	select ARCH_MIGHT_HAVE_PC_SERIO
  	select PCI if (!IA64_HP_SIM)
  	select ACPI if (!IA64_HP_SIM)
+	select ACPI_GENERIC_SLEEP if ACPI
  	select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
  	select HAVE_UNSTABLE_SCHED_CLOCK
  	select HAVE_IDE

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index b7d31ca..9804431 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig

@@ -22,6 +22,7 @@ config X86_64
  ### Arch settings
  config X86
  	def_bool y
+	select ACPI_GENERIC_SLEEP if ACPI

One more nit.  If you did

+	select ACPI_GENERIC_SLEEP if ACPI_SLEEP

here (and above for ia64), you'd avoid having to make ACPI_SLEEP
depend on ACPI_GENERIC_SLEEP which goes somewhat backwards.

In sleep.c,

#ifdef CONFIG_ACPI_SLEEP
acpi_target_system_state()
{
}
#endif

and CONFIG_ACPI_SLEEP depends on SUSPEND || HIBERNATION,
which one of them will be enabled on ARM64 so ACPI_SLEEP
will also enabled too.

So if we

+select ACPI_GENERIC_SLEEP if ACPI_SLEEP

and

+acpi-$(CONFIG_ACPI_GENERIC_SLEEP) += sleep.o

it will lead to errors for acpi_target_system_state() that
is declared but not defined, so I will keep the code as
it is, what do you think?

Thanks
Hanjun