f83810e0ec
[ Upstream commit 6add6dd345cb754ce18ff992c7264cabf31e59f6 ]
There is a 120ms delay implemented for allowing the XHCI host controller to
detect a U3 wakeup pulse. The intention is to wait for the device to retry
the wakeup event if the USB3 PORTSC doesn't reflect the RESUME link status
by the time it is checked. As per the USB3 specification:
tU3WakeupRetryDelay ("Table 7-12. LTSSM State Transition Timeouts")
This would allow the XHCI resume sequence to determine if the root hub
needs to be also resumed. However, in case there is no device connected,
or if there is only a HSUSB device connected, this delay would still affect
the overall resume timing.
Since this delay is solely for detecting U3 wake events (USB3 specific)
then ignore this delay for the disconnected case and the HSUSB connected
only case.
[skip helper function, rename usb3_connected variable -Mathias ]
Signed-off-by: Wesley Cheng <quic_wcheng@quicinc.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20231019102924.2797346-20-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.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.