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 06:24:34 +0000 (07:24 +0100)
commit08bf23c33979e0f44ff9ad1849c08067c7c3a46b
tree3c8f7d6ea0e597ef70b9f5aba5391dbf14f3f0c9
parentb7904d20157cb71587f2ae58ec7ed6b48204e88f
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