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

commit 13c65840feab8109194f9490c9870587173cb29d upstream.

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
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index b11521953485bb99892b85dd4c2c3e93378c2d56..8b58e7a009c1c8b4d7c848d3f3013ffe0045ae1f 100644 (file)
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -144,7 +144,7 @@ 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 07aa722bb12cd61a6a3a8767b2efe1dd826e6952..688bf665991bd4088623da361e26a6b5607eac5e 100644 (file)
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -332,7 +332,7 @@ 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 6d6868811e56ec93b8b615c079e6daea45c21b0d..fc7f48a7e8af186fcd54a810f909fe5b54a0d21b 100644 (file)
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -602,7 +602,7 @@ static irqreturn_t pcie_isr(int irq, void *dev_id)
        return IRQ_HANDLED;
 }
 
-void pcie_enable_notification(struct controller *ctrl)
+static void pcie_enable_notification(struct controller *ctrl)
 {
        u16 cmd, mask;
 
@@ -642,6 +642,17 @@ 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;