diff options
Diffstat (limited to 'arch/x86/kernel/i8259.c')
| -rw-r--r-- | arch/x86/kernel/i8259.c | 29 |
1 files changed, 21 insertions, 8 deletions
diff --git a/arch/x86/kernel/i8259.c b/arch/x86/kernel/i8259.c index 16cb827a5b27..be22f5a2192e 100644 --- a/arch/x86/kernel/i8259.c +++ b/arch/x86/kernel/i8259.c @@ -295,16 +295,11 @@ static void unmask_8259A(void) raw_spin_unlock_irqrestore(&i8259A_lock, flags); } -static void init_8259A(int auto_eoi) +static int probe_8259A(void) { unsigned long flags; unsigned char probe_val = ~(1 << PIC_CASCADE_IR); unsigned char new_val; - - i8259A_auto_eoi = auto_eoi; - - raw_spin_lock_irqsave(&i8259A_lock, flags); - /* * Check to see if we have a PIC. * Mask all except the cascade and read @@ -312,16 +307,28 @@ static void init_8259A(int auto_eoi) * have a PIC, we will read 0xff as opposed to the * value we wrote. */ + raw_spin_lock_irqsave(&i8259A_lock, flags); + outb(0xff, PIC_SLAVE_IMR); /* mask all of 8259A-2 */ outb(probe_val, PIC_MASTER_IMR); new_val = inb(PIC_MASTER_IMR); if (new_val != probe_val) { printk(KERN_INFO "Using NULL legacy PIC\n"); legacy_pic = &null_legacy_pic; - raw_spin_unlock_irqrestore(&i8259A_lock, flags); - return; } + raw_spin_unlock_irqrestore(&i8259A_lock, flags); + return nr_legacy_irqs(); +} + +static void init_8259A(int auto_eoi) +{ + unsigned long flags; + + i8259A_auto_eoi = auto_eoi; + + raw_spin_lock_irqsave(&i8259A_lock, flags); + outb(0xff, PIC_MASTER_IMR); /* mask all of 8259A-1 */ /* @@ -379,6 +386,10 @@ static int legacy_pic_irq_pending_noop(unsigned int irq) { return 0; } +static int legacy_pic_probe(void) +{ + return 0; +} struct legacy_pic null_legacy_pic = { .nr_legacy_irqs = 0, @@ -388,6 +399,7 @@ struct legacy_pic null_legacy_pic = { .mask_all = legacy_pic_noop, .restore_mask = legacy_pic_noop, .init = legacy_pic_int_noop, + .probe = legacy_pic_probe, .irq_pending = legacy_pic_irq_pending_noop, .make_irq = legacy_pic_uint_noop, }; @@ -400,6 +412,7 @@ struct legacy_pic default_legacy_pic = { .mask_all = mask_8259A, .restore_mask = unmask_8259A, .init = init_8259A, + .probe = probe_8259A, .irq_pending = i8259A_irq_pending, .make_irq = make_8259A_irq, }; |