powerpc: Convert power off logic to pm_power_off

The generic Linux framework to power off the machine is a function pointer
called pm_power_off. The trick about this pointer is that device drivers can
potentially implement it rather than board files.

Today on powerpc we set pm_power_off to invoke our generic full machine power
off logic which then calls ppc_md.power_off to invoke machine specific power
off.

However, when we want to add a power off GPIO via the "gpio-poweroff" driver,
this card house falls apart. That driver only registers itself if pm_power_off
is NULL to ensure it doesn't override board specific logic. However, since we
always set pm_power_off to the generic power off logic (which will just not
power off the machine if no ppc_md.power_off call is implemented), we can't
implement power off via the generic GPIO power off driver.

To fix this up, let's get rid of the ppc_md.power_off logic and just always use
pm_power_off as was intended. Then individual drivers such as the GPIO power off
driver can implement power off logic via that function pointer.

With this patch set applied and a few patches on top of QEMU that implement a
power off GPIO on the virt e500 machine, I can successfully turn off my virtual
machine after halt.

Signed-off-by: Alexander Graf <agraf@suse.de>
[mpe: Squash into one patch and update changelog based on cover letter]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

3 files changed, 4 insertions, 4 deletions

diff --git a/arch/powerpc/platforms/cell/celleb_setup.c b/arch/powerpc/platforms/cell/celleb_setup.c
index 34e8ce2976aa..90be8ec51686 100644
--- a/arch/powerpc/platforms/cell/celleb_setup.c
+++ b/arch/powerpc/platforms/cell/celleb_setup.c
@@ -142,6 +142,7 @@ static int __init celleb_probe_beat(void)
 	powerpc_firmware_features |= FW_FEATURE_CELLEB_ALWAYS
 		| FW_FEATURE_BEAT | FW_FEATURE_LPAR;
 	hpte_init_beat_v3();
+	pm_power_off = beat_power_off;
 
 	return 1;
 }
@@ -190,6 +191,7 @@ static int __init celleb_probe_native(void)
 
 	powerpc_firmware_features |= FW_FEATURE_CELLEB_ALWAYS;
 	hpte_init_native();
+	pm_power_off = rtas_power_off;
 
 	return 1;
 }
@@ -204,7 +206,6 @@ define_machine(celleb_beat) {
 	.setup_arch		= celleb_setup_arch_beat,
 	.show_cpuinfo		= celleb_show_cpuinfo,
 	.restart		= beat_restart,
-	.power_off		= beat_power_off,
 	.halt			= beat_halt,
 	.get_rtc_time		= beat_get_rtc_time,
 	.set_rtc_time		= beat_set_rtc_time,
@@ -230,7 +231,6 @@ define_machine(celleb_native) {
 	.setup_arch		= celleb_setup_arch_native,
 	.show_cpuinfo		= celleb_show_cpuinfo,
 	.restart		= rtas_restart,
-	.power_off		= rtas_power_off,
 	.halt			= rtas_halt,
 	.get_boot_time		= rtas_get_boot_time,
 	.get_rtc_time		= rtas_get_rtc_time,
diff --git a/arch/powerpc/platforms/cell/qpace_setup.c b/arch/powerpc/platforms/cell/qpace_setup.c
index 6e3409d590ac..d328140dc6f5 100644
--- a/arch/powerpc/platforms/cell/qpace_setup.c
+++ b/arch/powerpc/platforms/cell/qpace_setup.c
@@ -127,6 +127,7 @@ static int __init qpace_probe(void)
 		return 0;
 
 	hpte_init_native();
+	pm_power_off = rtas_power_off;
 
 	return 1;
 }
@@ -137,7 +138,6 @@ define_machine(qpace) {
 	.setup_arch		= qpace_setup_arch,
 	.show_cpuinfo		= qpace_show_cpuinfo,
 	.restart		= rtas_restart,
-	.power_off		= rtas_power_off,
 	.halt			= rtas_halt,
 	.get_boot_time		= rtas_get_boot_time,
 	.get_rtc_time		= rtas_get_rtc_time,
diff --git a/arch/powerpc/platforms/cell/setup.c b/arch/powerpc/platforms/cell/setup.c
index 6ae25fb62015..d62aa982d530 100644
--- a/arch/powerpc/platforms/cell/setup.c
+++ b/arch/powerpc/platforms/cell/setup.c
@@ -259,6 +259,7 @@ static int __init cell_probe(void)
 		return 0;
 
 	hpte_init_native();
+	pm_power_off = rtas_power_off;
 
 	return 1;
 }
@@ -269,7 +270,6 @@ define_machine(cell) {
 	.setup_arch		= cell_setup_arch,
 	.show_cpuinfo		= cell_show_cpuinfo,
 	.restart		= rtas_restart,
-	.power_off		= rtas_power_off,
 	.halt			= rtas_halt,
 	.get_boot_time		= rtas_get_boot_time,
 	.get_rtc_time		= rtas_get_rtc_time,