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Ravi Chandra Sadineni
83a62c51ba
On chromebooks we depend on wakeup count to identify the wakeup source. But currently USB devices do not increment the wakeup count when they trigger the remote wake. This patch addresses the same. Resume condition is reported differently on USB 2.0 and USB 3.0 devices. On USB 2.0 devices, a wake capable device, if wake enabled, drives resume signal to indicate a remote wake (USB 2.0 spec section 7.1.7.7). The upstream facing port then sets C_PORT_SUSPEND bit and reports a port change event (USB 2.0 spec section 11.24.2.7.2.3). Thus if a port has resumed before driving the resume signal from the host and C_PORT_SUSPEND is set, then the device attached to the given port might be the reason for the last system wakeup. Increment the wakeup count for the same. On USB 3.0 devices, a function may signal that it wants to exit from device suspend by sending a Function Wake Device Notification to the host (USB3.0 spec section 8.5.6.4) Thus on receiving the Function Wake, increment the wakeup count. Signed-off-by: Ravi Chandra Sadineni <ravisadineni@chromium.org> Acked-by: Alan Stern <stern@rowland.harvard.edu> Cc: stable <stable@vger.kernel.org> 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.
See Documentation/00-INDEX for a list of what is contained in each file.
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.