Merge tag 'pci-v4.21-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci

Pull PCI updates from Bjorn Helgaas:

 - Remove unused lists from ASPM pcie_link_state (Frederick Lawler)

 - Fix Broadcom CNB20LE host bridge unintended sign extension (Colin Ian
   King)

 - Expand Kconfig "PF" acronyms (Randy Dunlap)

 - Update MAINTAINERS for arch/x86/kernel/early-quirks.c (Bjorn Helgaas)

 - Add missing include to drivers/pci.h (Alexandru Gagniuc)

 - Override Synopsys USB 3.x HAPS device class so dwc3-haps can claim it
   instead of xhci (Thinh Nguyen)

 - Clean up P2PDMA documentation (Randy Dunlap)

 - Allow runtime PM even if driver doesn't supply callbacks (Jarkko
   Nikula)

 - Remove status check after submitting Switchtec MRPC Firmware Download
   commands to avoid Completion Timeouts (Kelvin Cao)

 - Set Switchtec coherent DMA mask to allow 64-bit DMA (Boris Glimcher)

 - Fix Switchtec SWITCHTEC_IOCTL_EVENT_IDX_ALL flag overwrite issue
   (Joey Zhang)

 - Enable write combining for Switchtec MRPC Input buffers (Kelvin Cao)

 - Add Switchtec MRPC DMA mode support (Wesley Sheng)

 - Skip VF scanning on powerpc, which does this in firmware (Sebastian
   Ott)

 - Add Amlogic Meson PCIe controller driver and DT bindings (Yue Wang)

 - Constify histb dw_pcie_host_ops structure (Julia Lawall)

 - Support multiple power domains for imx6 (Leonard Crestez)

 - Constify layerscape driver data (Stefan Agner)

 - Update imx6 Kconfig to allow imx6 PCIe in imx7 kernel (Trent Piepho)

 - Support armada8k GPIO reset (Baruch Siach)

 - Support suspend/resume support on imx6 (Leonard Crestez)

 - Don't hard-code DesignWare DBI/ATU offst (Stephen Warren)

 - Skip i.MX6 PHY setup on i.MX7D (Andrey Smirnov)

 - Remove Jianguo Sun from HiSilicon STB maintainers (Lorenzo Pieralisi)

 - Mask DesignWare interrupts instead of disabling them to avoid lost
   interrupts (Marc Zyngier)

 - Add locking when acking DesignWare interrupts (Marc Zyngier)

 - Ack DesignWare interrupts in the proper callbacks (Marc Zyngier)

 - Use devm resource parser in mediatek (Honghui Zhang)

 - Remove unused mediatek "num-lanes" DT property (Honghui Zhang)

 - Add UniPhier PCIe controller driver and DT bindings (Kunihiko
   Hayashi)

 - Enable MSI for imx6 downstream components (Richard Zhu)

* tag 'pci-v4.21-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (40 commits)
  PCI: imx: Enable MSI from downstream components
  s390/pci: skip VF scanning
  PCI/IOV: Add flag so platforms can skip VF scanning
  PCI/IOV: Factor out sriov_add_vfs()
  PCI: uniphier: Add UniPhier PCIe host controller support
  dt-bindings: PCI: Add UniPhier PCIe host controller description
  PCI: amlogic: Add the Amlogic Meson PCIe controller driver
  dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe controller
  arm64: dts: mt7622: Remove un-used property for PCIe
  arm: dts: mt7623: Remove un-used property for PCIe
  dt-bindings: PCI: MediaTek: Remove un-used property
  PCI: mediatek: Remove un-used variant in struct mtk_pcie_port
  MAINTAINERS: Remove Jianguo Sun from HiSilicon STB DWC entry
  PCI: dwc: Don't hard-code DBI/ATU offset
  PCI: imx: Add imx6sx suspend/resume support
  PCI: armada8k: Add support for gpio controlled reset signal
  PCI: dwc: Adjust Kconfig to allow IMX6 PCIe host on IMX7
  PCI: dwc: layerscape: Constify driver data
  PCI: imx: Add multi-pd support
  PCI: Override Synopsys USB 3.x HAPS device class
  ...

1 files changed, 12 insertions, 15 deletions

diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
index ea55444e6ead..79b1610a8beb 100644
--- a/drivers/pci/pci-driver.c
+++ b/drivers/pci/pci-driver.c
@@ -1251,30 +1251,29 @@ static int pci_pm_runtime_suspend(struct device *dev)
 		return 0;
 	}
 
-	if (!pm || !pm->runtime_suspend)
-		return -ENOSYS;
-
 	pci_dev->state_saved = false;
-	error = pm->runtime_suspend(dev);
-	if (error) {
+	if (pm && pm->runtime_suspend) {
+		error = pm->runtime_suspend(dev);
 		/*
 		 * -EBUSY and -EAGAIN is used to request the runtime PM core
 		 * to schedule a new suspend, so log the event only with debug
 		 * log level.
 		 */
-		if (error == -EBUSY || error == -EAGAIN)
+		if (error == -EBUSY || error == -EAGAIN) {
 			dev_dbg(dev, "can't suspend now (%pf returned %d)\n",
 				pm->runtime_suspend, error);
-		else
+			return error;
+		} else if (error) {
 			dev_err(dev, "can't suspend (%pf returned %d)\n",
 				pm->runtime_suspend, error);
-
-		return error;
+			return error;
+		}
 	}
 
 	pci_fixup_device(pci_fixup_suspend, pci_dev);
 
-	if (!pci_dev->state_saved && pci_dev->current_state != PCI_D0
+	if (pm && pm->runtime_suspend
+	    && !pci_dev->state_saved && pci_dev->current_state != PCI_D0
 	    && pci_dev->current_state != PCI_UNKNOWN) {
 		WARN_ONCE(pci_dev->current_state != prev,
 			"PCI PM: State of device not saved by %pF\n",
@@ -1292,7 +1291,7 @@ static int pci_pm_runtime_suspend(struct device *dev)
 
 static int pci_pm_runtime_resume(struct device *dev)
 {
-	int rc;
+	int rc = 0;
 	struct pci_dev *pci_dev = to_pci_dev(dev);
 	const struct dev_pm_ops *pm = dev->driver ? dev->driver->pm : NULL;
 
@@ -1306,14 +1305,12 @@ static int pci_pm_runtime_resume(struct device *dev)
 	if (!pci_dev->driver)
 		return 0;
 
-	if (!pm || !pm->runtime_resume)
-		return -ENOSYS;
-
 	pci_fixup_device(pci_fixup_resume_early, pci_dev);
 	pci_enable_wake(pci_dev, PCI_D0, false);
 	pci_fixup_device(pci_fixup_resume, pci_dev);
 
-	rc = pm->runtime_resume(dev);
+	if (pm && pm->runtime_resume)
+		rc = pm->runtime_resume(dev);
 
 	pci_dev->runtime_d3cold = false;