If platform_get_irq() returns IRQ0 (considered invalid according to Linus)
the driver blithely passes it to ata_host_activate() that treats IRQ0 as
a sign that libata should use polling and thus complains about non-NULL 
IRQ handler passed to it. Deny IRQ0 right away, returning -EINVAL from
the probe() method...

Fixes: 76a40ca82f34 ("Add Palmchip BK3710 PATA controller driver.")
Signed-off-by: Sergey Shtylyov <redacted>

---
 drivers/ata/pata_bk3710.c |    2 ++
 1 file changed, 2 insertions(+)

Index: linux-block/drivers/ata/pata_bk3710.c
===================================================================

--- linux-block.orig/drivers/ata/pata_bk3710.c
+++ linux-block/drivers/ata/pata_bk3710.c

@@ -317,6 +317,8 @@ static int __init pata_bk3710_probe(stru
 		pr_err(DRV_NAME ": failed to get IRQ resource\n");
 		return irq;
 	}
+	if (!irq)
+		return -EINVAL;
 
 	base = devm_ioremap_resource(&pdev->dev, mem);
 	if (IS_ERR(base))