Linux mainline fork with MSM8998 patches | https://mainline.space | Currently supported devices:
OnePlus 5/5T, Xiaomi Mi 6, F(x)tec Pro¹ (2019 QX1000 model) & Sony Xperia XZ Premium (UNTESTED!)
The pullup does not need to be enabled at below situations: - For platforms which the hardware pullup starts after setting register even they do not see the VBUS. If the pullup is always enabled for these platforms, it will consume more power and break the USB IF compliance tests [1]. - For platforms which need to do BC 1.2 charger detection after seeing the VBUS. Pullup D+ will break the charger detection flow. - For platforms which the system suspend is allowed when the connection with host is there but the bus is not at suspend. For these platforms, it is better to disable pullup when entering the system suspend otherwise the host may confuse the device behavior after controller is in low power mode. Disable pullup is considered as a disconnection event from host side. [1] USB-IF Full and Low Speed Compliance Test Procedure F Back-voltage Testing Section 7.2.1 of the USB specification requires that no device shall supply (source) current on VBUS at its upstream facing port at any time. From VBUS on its upstream facing port, a device may only draw (sink) current. They may not provide power to the pull-up resistor on D+/D- unless VBUS is present (see Section 7.1.5). Signed-off-by: Peter Chen <peter.chen@nxp.com> Link: https://lore.kernel.org/r/20201230051114.21370-1-peter.chen@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
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.