[PATCH AUTOSEL 5.4 135/205] PCI: pciehp: Do not disable interrupt twice on suspend

[Sasha Levin <sashal@kernel.org>]

From: Mika Westerberg <mika.westerberg@linux.intel.com>

[ Upstream commit 75fcc0ce72e5cea2e357cdde858216c5bad40442 ]

We try to keep PCIe hotplug ports runtime suspended when entering system
suspend. Because the PCIe portdrv sets the DPM_FLAG_NEVER_SKIP flag, the PM
core always calls system suspend/resume hooks even if the device is left
runtime suspended. Since PCIe hotplug driver re-used the same function for
both runtime suspend and system suspend, it ended up disabling hotplug
interrupt twice and the second time following was printed:

  pciehp 0000:03:01.0:pcie204: pcie_do_write_cmd: no response from device

Prevent this from happening by checking whether the device is already
runtime suspended when the system suspend hook is called.

Fixes: 9c62f0bfb832 ("PCI: pciehp: Implement runtime PM callbacks")
Link: https://lore.kernel.org/r/20191029170022.57528-1-mika.westerberg@linux.intel.com
Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/pci/hotplug/pciehp_core.c | 25 +++++++++++++++++++++++--
 1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index b3122c151b80..56daad828c9e 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -253,7 +253,7 @@ static bool pme_is_native(struct pcie_device *dev)
 	return pcie_ports_native || host->native_pme;
 }
 
-static int pciehp_suspend(struct pcie_device *dev)
+static void pciehp_disable_interrupt(struct pcie_device *dev)
 {
 	/*
 	 * Disable hotplug interrupt so that it does not trigger
@@ -261,7 +261,19 @@ static int pciehp_suspend(struct pcie_device *dev)
 	 */
 	if (pme_is_native(dev))
 		pcie_disable_interrupt(get_service_data(dev));
+}
 
+#ifdef CONFIG_PM_SLEEP
+static int pciehp_suspend(struct pcie_device *dev)
+{
+	/*
+	 * If the port is already runtime suspended we can keep it that
+	 * way.
+	 */
+	if (dev_pm_smart_suspend_and_suspended(&dev->port->dev))
+		return 0;
+
+	pciehp_disable_interrupt(dev);
 	return 0;
 }
 
@@ -279,6 +291,7 @@ static int pciehp_resume_noirq(struct pcie_device *dev)
 
 	return 0;
 }
+#endif
 
 static int pciehp_resume(struct pcie_device *dev)
 {
@@ -292,6 +305,12 @@ static int pciehp_resume(struct pcie_device *dev)
 	return 0;
 }
 
+static int pciehp_runtime_suspend(struct pcie_device *dev)
+{
+	pciehp_disable_interrupt(dev);
+	return 0;
+}
+
 static int pciehp_runtime_resume(struct pcie_device *dev)
 {
 	struct controller *ctrl = get_service_data(dev);
@@ -318,10 +337,12 @@ static struct pcie_port_service_driver hpdriver_portdrv = {
 	.remove		= pciehp_remove,
 
 #ifdef	CONFIG_PM
+#ifdef	CONFIG_PM_SLEEP
 	.suspend	= pciehp_suspend,
 	.resume_noirq	= pciehp_resume_noirq,
 	.resume		= pciehp_resume,
-	.runtime_suspend = pciehp_suspend,
+#endif
+	.runtime_suspend = pciehp_runtime_suspend,
 	.runtime_resume	= pciehp_runtime_resume,
 #endif	/* PM */
 };
-- 
2.20.1