[PATCH] Bug fix for PME interrupt handler, add Root Status check

[Qiang <zhengqiang10@huawei.com>]

PCIe PME and hot plug share same interrupt number. In some special case,
Link down event cause hot plug interrupt, devices is not disconnected,
But read config will return 0xff.

In that case, PME work function will run and not return Because
Root Status PME bit always 1 and can not be cleared.

This patch add Root Status check in PME interrupt handler,
Just do same as pciehp isr Slot status check.

Signed-off-by: Qiang Zheng <zhengqiang10@huawei.com>
---
 drivers/pci/pcie/pme.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/pcie/pme.c b/drivers/pci/pcie/pme.c
index fafdb16..67144f5 100644
--- a/drivers/pci/pcie/pme.c
+++ b/drivers/pci/pcie/pme.c
@@ -273,7 +273,7 @@ static irqreturn_t pcie_pme_irq(int irq, void *context)
 	spin_lock_irqsave(&data->lock, flags);
 	pcie_capability_read_dword(port, PCI_EXP_RTSTA, &rtsta);
 
-	if (!(rtsta & PCI_EXP_RTSTA_PME)) {
+	if (rtsta == (u32)(~0) || !(rtsta & PCI_EXP_RTSTA_PME)) {
 		spin_unlock_irqrestore(&data->lock, flags);
 		return IRQ_NONE;
 	}
-- 
1.9.1