2847c46c61
This reverts commit 5d5323a6f3625f101dbfa94ba3ef7706cce38760. That commit effectively disabled Intel host initiated U1/U2 lpm for devices with periodic endpoints. Before that commit we disabled host initiated U1/U2 lpm if the exit latency was larger than any periodic endpoint service interval, this is according to xhci spec xhci 1.1 specification section 4.23.5.2 After that commit we incorrectly checked that service interval was smaller than U1/U2 inactivity timeout. This is not relevant, and can't happen for Intel hosts as previously set U1/U2 timeout = 105% * service interval. Patch claimed it solved cases where devices can't be enumerated because of bandwidth issues. This might be true but it's a side effect of accidentally turning off lpm. exit latency calculations have been revised since then Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com> Link: https://lore.kernel.org/r/20210820123503.2605901-5-mathias.nyman@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.