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>
This commit is contained in:
Alexander Graf
2014-10-13 16:01:09 +02:00
committed by Michael Ellerman
parent 0df1f2487d
commit 9178ba294b
21 changed files with 66 additions and 58 deletions

View File

@@ -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,