PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume

After a suspend/resume cycle the Presence Detect or Data Link Layer Status
Changed bits might be set.  If we don't clear them those events will not
fire anymore and nothing happens for instance when a device is now
hot-unplugged.

Fix this by clearing those bits in a newly introduced function
pcie_reenable_notification().  This should be fine because immediately
after, we check if the adapter is still present by reading directly from
the status register.

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>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: stable@vger.kernel.org

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 88e917c9120fd2a42f05c0a26434017e8bfc2913..5f892065585e8d00611a959cce462520d3c7c52b 100644 (file)
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -121,7 +121,7 @@ struct controller *pcie_init(struct pcie_device *dev);
 int pcie_init_notification(struct controller *ctrl);
 int pciehp_enable_slot(struct slot *p_slot);
 int pciehp_disable_slot(struct slot *p_slot);
-void pcie_enable_notification(struct controller *ctrl);
+void pcie_reenable_notification(struct controller *ctrl);
 int pciehp_power_on_slot(struct slot *slot);
 void pciehp_power_off_slot(struct slot *slot);
 void pciehp_get_power_status(struct slot *slot, u8 *status);

diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 332b723ff9e63a696fb3c299addef91030af2256..44a6a63802d5628bdc7e400f12e43f263047bd4b 100644 (file)
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -283,7 +283,7 @@ static int pciehp_resume(struct pcie_device *dev)
        ctrl = get_service_data(dev);
 
        /* reinitialize the chipset's event detection logic */
-       pcie_enable_notification(ctrl);
+       pcie_reenable_notification(ctrl);
 
        slot = ctrl->slot;
 

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 74a7f7bde2632267cfdd654160ea9e4759196425..022e68f7c3ec6a7b5bde52f24c02199f5ebf4d71 100644 (file)
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -667,7 +667,7 @@ static irqreturn_t pcie_isr(int irq, void *dev_id)
        return handled;
 }
 
-void pcie_enable_notification(struct controller *ctrl)
+static void pcie_enable_notification(struct controller *ctrl)
 {
        u16 cmd, mask;
 
@@ -705,6 +705,17 @@ void pcie_enable_notification(struct controller *ctrl)
                 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd);
 }
 
+void pcie_reenable_notification(struct controller *ctrl)
+{
+       /*
+        * Clear both Presence and Data Link Layer Changed to make sure
+        * those events still fire after we have re-enabled them.
+        */
+       pcie_capability_write_word(ctrl->pcie->port, PCI_EXP_SLTSTA,
+                                  PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC);
+       pcie_enable_notification(ctrl);
+}
+
 static void pcie_disable_notification(struct controller *ctrl)
 {
        u16 mask;