PCI/ERR: Return status of pcie_do_recovery()

As per the DPC Enhancements ECN [1], sec 4.5.1, table 4-4, if the OS
supports Error Disconnect Recover (EDR), it must invalidate the software
state associated with child devices of the port without attempting to
access the child device hardware. In addition, if the OS supports DPC, it
must attempt to recover the child devices if the port implements the DPC
Capability. If the OS continues operation, the OS must inform the firmware
of the status of the recovery operation via the _OST method.

Return the result of pcie_do_recovery() so we can report it to firmware via
_OST.

[1] Downstream Port Containment Related Enhancements ECN, Jan 28, 2019,
    affecting PCI Firmware Specification, Rev. 3.2
    https://members.pcisig.com/wg/PCI-SIG/document/12888

Link: https://lore.kernel.org/r/eb60ec89448769349c6722954ffbf2de163155b5.1585000084.git.sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>

1 files changed, 6 insertions, 4 deletions

diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c
index 9d5b71a7f837..0c40488da651 100644
--- a/drivers/pci/pcie/err.c
+++ b/drivers/pci/pcie/err.c
@@ -146,9 +146,9 @@ out:
 	return 0;
 }
 
-void pcie_do_recovery(struct pci_dev *dev,
-		      enum pci_channel_state state,
-		      pci_ers_result_t (*reset_link)(struct pci_dev *pdev))
+pci_ers_result_t pcie_do_recovery(struct pci_dev *dev,
+			enum pci_channel_state state,
+			pci_ers_result_t (*reset_link)(struct pci_dev *pdev))
 {
 	pci_ers_result_t status = PCI_ERS_RESULT_CAN_RECOVER;
 	struct pci_bus *bus;
@@ -200,11 +200,13 @@ void pcie_do_recovery(struct pci_dev *dev,
 	pci_aer_clear_device_status(dev);
 	pci_cleanup_aer_uncorrect_error_status(dev);
 	pci_info(dev, "device recovery successful\n");
-	return;
+	return status;
 
 failed:
 	pci_uevent_ers(dev, PCI_ERS_RESULT_DISCONNECT);
 
 	/* TODO: Should kernel panic here? */
 	pci_info(dev, "device recovery failed\n");
+
+	return status;
 }