PCI: pciehp: Do not handle events if interrupts are masked

PCIe native hotplug shares MSI vector with native PME so the interrupt
handler might get called even the hotplug interrupt is masked. In that case
we should not handle any events because the interrupt was not meant for us.

Modify the PCIe hotplug interrupt handler to check this accordingly and
bail out if it finds out that the interrupt was not about hotplug.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Lukas Wunner <lukas@wunner.de>

drivers/pci/hotplug/pciehp_hpc.c

@@ -518,9 +518,11 @@ static irqreturn_t pciehp_isr(int irq, void *dev_id)
 	u16 status, events;
 
 	/*
-	 * Interrupts only occur in D3hot or shallower (PCIe r4.0, sec 6.7.3.4).
+	 * Interrupts only occur in D3hot or shallower and only if enabled
+	 * in the Slot Control register (PCIe r4.0, sec 6.7.3.4).
 	 */
-	if (pdev->current_state == PCI_D3cold)
+	if (pdev->current_state == PCI_D3cold ||
+	    (!(ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE) && !pciehp_poll_mode))
 		return IRQ_NONE;
 
 	/*