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,
 };