bf45e4f92c
commit ceb94bc52c437463f0903e61060a94a2226fb672 upstream. This patch adds a safety connection way for "forced_b_device" with "workaround_for_vbus" like below: < Example for R-Car E3 Ebisu > # modprobe <any usb gadget driver> # echo 1 > /sys/kernel/debug/ee020000.usb/b_device (connect a usb cable to host side.) # echo 2 > /sys/kernel/debug/ee020000.usb/b_device Previous code should have connected a usb cable before the "b_device" is set to 1 on the Ebisu board. However, if xHCI driver on the board is probed, it causes some troubles: - Conflicts USB VBUS/signals between the board and another host. - "Cannot enable. Maybe the USB cable is bad?" might happen on both the board and another host with a usb hub. - Cannot enumerate a usb gadget correctly because an interruption of VBUS change happens unexpectedly. Reported-by: Kazuya Mizuguchi <kazuya.mizuguchi.ks@renesas.com> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com> Signed-off-by: Pavel Machek <pavel@denx.de>
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.