xhci-pci: Set runtime PM as default policy on all xHC 1.2 or later devices
authorMario Limonciello <mario.limonciello@amd.com>
Mon, 24 Oct 2022 14:27:19 +0000 (17:27 +0300)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 25 Oct 2022 17:53:41 +0000 (19:53 +0200)
commita611bf473d1f77b70f7188b5577542cb39b4701b
treeaee434c88d2324fa7170c9513845cdb24fda2b6e
parent34cd2db408d591bc15771cbcc90939ade0a99a21
xhci-pci: Set runtime PM as default policy on all xHC 1.2 or later devices

For optimal power consumption of USB4 routers the XHCI PCIe endpoint
used for tunneling must be in D3.  Historically this is accomplished
by a long list of PCIe IDs that correspond to these endpoints because
the xhci_hcd driver will not default to allowing runtime PM for all
devices.

As both AMD and Intel have released new products with new XHCI controllers
this list continues to grow. In reviewing the XHCI specification v1.2 on
page 607 there is already a requirement that the PCI power management
states D3hot and D3cold must be supported.

In the quirk list, use this to indicate that runtime PM should be allowed
on XHCI controllers. The following controllers are known to be xHC 1.2 and
dropped explicitly:
* AMD Yellow Carp
* Intel Alder Lake
* Intel Meteor Lake
* Intel Raptor Lake

[keep PCI ID for Alder Lake PCH for recently added quirk -Mathias]

Cc: stable@vger.kernel.org
Suggested-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://www.intel.com/content/dam/www/public/us/en/documents/technical-specifications/extensible-host-controler-interface-usb-xhci.pdf
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20221024142720.4122053-4-mathias.nyman@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-pci.c