diff options
Diffstat (limited to 'arch/parisc/kernel/firmware.c')
| -rw-r--r-- | arch/parisc/kernel/firmware.c | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/arch/parisc/kernel/firmware.c b/arch/parisc/kernel/firmware.c index 6817892a2c58..cc124d9f1f7f 100644 --- a/arch/parisc/kernel/firmware.c +++ b/arch/parisc/kernel/firmware.c @@ -1232,15 +1232,18 @@ int __init pdc_soft_power_info(unsigned long *power_reg) } /* - * pdc_soft_power_button - Control the soft power button behaviour - * @sw_control: 0 for hardware control, 1 for software control + * pdc_soft_power_button{_panic} - Control the soft power button behaviour + * @sw_control: 0 for hardware control, 1 for software control * * * This PDC function places the soft power button under software or * hardware control. - * Under software control the OS may control to when to allow to shut - * down the system. Under hardware control pressing the power button + * Under software control the OS may control to when to allow to shut + * down the system. Under hardware control pressing the power button * powers off the system immediately. + * + * The _panic version relies on spin_trylock to prevent deadlock + * on panic path. */ int pdc_soft_power_button(int sw_control) { @@ -1254,6 +1257,22 @@ int pdc_soft_power_button(int sw_control) return retval; } +int pdc_soft_power_button_panic(int sw_control) +{ + int retval; + unsigned long flags; + + if (!spin_trylock_irqsave(&pdc_lock, flags)) { + pr_emerg("Couldn't enable soft power button\n"); + return -EBUSY; /* ignored by the panic notifier */ + } + + retval = mem_pdc_call(PDC_SOFT_POWER, PDC_SOFT_POWER_ENABLE, __pa(pdc_result), sw_control); + spin_unlock_irqrestore(&pdc_lock, flags); + + return retval; +} + /* * pdc_io_reset - Hack to avoid overlapping range registers of Bridges devices. * Primarily a problem on T600 (which parisc-linux doesn't support) but |