xhci: Detect lpm incapable xHC USB3 roothub ports from ACPI tables
authorMathias Nyman <mathias.nyman@linux.intel.com>
Mon, 16 Jan 2023 14:22:16 +0000 (16:22 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 24 Jan 2023 06:22:44 +0000 (07:22 +0100)
commit418e2c756d65276237e45456d51d7144a3c1a7a1
treedfc4bbce258af19a1ea6dc64ac60725bc4965fdb
parent10cb7d53be5fd02a6190991cb567b355356eeb75
xhci: Detect lpm incapable xHC USB3 roothub ports from ACPI tables

commit 74622f0a81d0c2bcfc39f9192b788124e8c7f0af upstream.

USB3 ports on xHC hosts may have retimers that cause too long
exit latency to work with native USB3 U1/U2 link power management states.

For now only use usb_acpi_port_lpm_incapable() to evaluate if port lpm
should be disabled while setting up the USB3 roothub.

Other ways to identify lpm incapable ports can be added here later if
ACPI _DSM does not exist.

Limit this to Intel hosts for now, this is to my knowledge only
an Intel issue.

Cc: stable@vger.kernel.org
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20230116142216.1141605-8-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/usb/host/xhci-pci.c