Re: [PATCH 1/2] PCI: pciehp: Do not disable interrupt twice on suspend

[Kai-Heng Feng]

at 20:50, Mika Westerberg <mika.westerb...@linux.intel.com> wrote:

We try to keep PCIe hotplug ports runtime suspended when entering system
suspend. Due to the fact that the PCIe portdrv sets NEVER_SKIP driver PM
flag the PM core always calls system suspend/resume hooks even if the
device is left runtime suspended. Since PCIe hotplug driver re-uses the
same function for both it ends up disabling hotplug interrupt twice and
the second time following is 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 system suspend hook is called.

Fixes: 9c62f0bfb832 ("PCI: pciehp: Implement runtime PM callbacks")
Reported-by: Kai Heng Feng <kai.heng.f...@canonical.com>
Signed-off-by: Mika Westerberg <mika.westerb...@linux.intel.com>

Tested-by: Kai-Heng Feng <kai.heng.f...@canonical.com>

---
 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 6ad0d86762cb..3f8c13ddb3e8 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -248,7 +248,7 @@ 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
@@ -256,7 +256,19 @@ 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;
 }

@@ -274,6 +286,7 @@ static int pciehp_resume_noirq(struct pcie_device *dev)

        return 0;
 }
+#endif

 static int pciehp_resume(struct pcie_device *dev)
 {
@@ -287,6 +300,12 @@ 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);

@@ -313,10 +332,12 @@ 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,
+#endif
        .resume         = pciehp_resume,
-       .runtime_suspend = pciehp_suspend,
+       .runtime_suspend = pciehp_runtime_suspend,
        .runtime_resume = pciehp_runtime_resume,
 #endif /* PM */
 };
--
2.20.1