751faedf06
Adds 80000 us sleep when the usb cable is plugged in to hopefully avoid bouncing contacts. Upon pluging in the usb cable vbus will bounce for some time, causing cpcap to dissconnect charging due to detecting an undervoltage condition. This is a scope of vbus on xt894 while quickly inserting the usb cable with firm force, probed at the far side of the usb socket and vbus loaded with approx 1k: http://uvos.xyz/maserati/usbplug.jpg. As can clearly be seen, vbus is all over the place for the first 15 ms or so with a small blip at ~40 ms this causes the cpcap to trip up and disable charging again. The delay helps cpcap_usb_detect avoid the worst of this. It is, however, still not ideal as strong vibrations can cause the issue to reapear any time during charging. I have however not been able to cause the device to stop charging due to this in practice as it is hard to vibrate the device such that the vbus pins start bouncing again but cpcap_usb_detect is not called again due to a detected disconnect/reconnect event. Signed-off-by: Carl Philipp Klemm <philipp@uvos.xyz> Tested-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com> |
||
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| 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 | ||
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.