From 13c65840feab8109194f9490c9870587173cb29d Mon Sep 17 00:00:00 2001
From: Mika Westerberg <mika.westerberg@linux.intel.com>
Date: Wed, 23 May 2018 17:14:39 -0500
Subject: [PATCH] PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume
Git-commit: 13c65840feab8109194f9490c9870587173cb29d
Patch-mainline: v4.18-rc1
References: bsc#1051510
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
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/pci/hotplug/pciehp.h | 2 +-
drivers/pci/hotplug/pciehp_core.c | 2 +-
drivers/pci/hotplug/pciehp_hpc.c | 13 ++++++++++++-
3 files changed, 14 insertions(+), 3 deletions(-)
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 88e917c9120f..5f892065585e 100644
--- 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 332b723ff9e6..44a6a63802d5 100644
--- 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 74a7f7bde263..022e68f7c3ec 100644
--- 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;
--
2.18.0