PCI: pciehp: Enable link state change notifications
Enable the Link state notifications unconditionally. Enable the
presence detection notification only if attention button is absent.
This was discussed at this thread:
https://lkml.kernel.org/r/529E5C0E.80903@gmail.com
Signed-off-by: Rajat Jain <rajatxjain@gmail.com>
Signed-off-by: Rajat Jain <rajatjain@juniper.net>
Signed-off-by: Guenter Roeck <groeck@juniper.net>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index b413dce..245a3cb 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -600,9 +600,17 @@
* when it is cleared in the interrupt service routine, and
* next power fault detected interrupt was notified again.
*/
- cmd = PCI_EXP_SLTCTL_PDCE;
+
+ /*
+ * Always enable link events: thus link-up and link-down shall
+ * always be treated as hotplug and unplug respectively. Enable
+ * presence detect only if Attention Button is not present.
+ */
+ cmd = PCI_EXP_SLTCTL_DLLSCE;
if (ATTN_BUTTN(ctrl))
cmd |= PCI_EXP_SLTCTL_ABPE;
+ else
+ cmd |= PCI_EXP_SLTCTL_PDCE;
if (MRL_SENS(ctrl))
cmd |= PCI_EXP_SLTCTL_MRLSCE;
if (!pciehp_poll_mode)
@@ -610,7 +618,8 @@
mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
- PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE);
+ PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
+ PCI_EXP_SLTCTL_DLLSCE);
pcie_write_cmd(ctrl, cmd, mask);
}