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PCI: Get rid of dev->has_secondary_link flag

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In some systems, the Device/Port Type in the PCI Express Capabilities
register incorrectly identifies upstream ports as downstream ports.

d0751b98df ("PCI: Add dev->has_secondary_link to track downstream PCIe
links") addressed this by adding pci_dev.has_secondary_link, which is set
for downstream ports.  But this is confusing because pci_pcie_type()
sometimes gives the wrong answer, and it's not obvious that we should use
pci_dev.has_secondary_link instead.

Reduce the confusion by correcting the type of the port itself so that
pci_pcie_type() returns the actual type regardless of what the Device/Port
Type register claims it is.  Update the users to call pci_pcie_type() and
pcie_downstream_port() accordingly, and remove pci_dev.has_secondary_link
completely.

Link: https://lore.kernel.org/linux-pci/20190703133953.GK128603@google.com/
Suggested-by: Bjorn Helgaas <bhelgaas@google.com>
Link: https://lore.kernel.org/r/20190822085553.62697-2-mika.westerberg@linux.intel.com
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
This commit is contained in:
Mika Westerberg
2019-08-22 11:55:53 +03:00
committed by Bjorn Helgaas
parent 984998e340
commit ca78410403
6 changed files with 37 additions and 28 deletions
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8
drivers/pci/pcie/aspm.c
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@@ -913,10 +913,10 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
/*
* We allocate pcie_link_state for the component on the upstream
* end of a Link, so there's nothing to do unless this device has a
* Link on its secondary side.
* end of a Link, so there's nothing to do unless this device is
* downstream port.
*/
if (!pdev->has_secondary_link)
if (!pcie_downstream_port(pdev))
return;
/* VIA has a strange chipset, root port is under a bridge */
@@ -1070,7 +1070,7 @@ static int __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
if (!pci_is_pcie(pdev))
return 0;
if (pdev->has_secondary_link)
if (pcie_downstream_port(pdev))
parent = pdev;
if (!parent || !parent->link_state)
return -EINVAL;