Fork of alistair23 Linux kernel for reMarkable from https://github.com/alistair23/linux
14486c8261
The WLAN device may exist yet not be usable. This can happen when the WLAN device is controllable by both the host and some platform internal component. We need some arbritration that is vendor specific, but when the device is not available for the host, we need to reflect this state towards the user space. Add a reason field to the rfkill object (and event) so that userspace can know why the device is in rfkill: because some other platform component currently owns the device, or because the actual hw rfkill signal is asserted. Capable userspace can now determine the reason for the rfkill and possibly do some negotiation on a side band channel using a proprietary protocol to gain ownership on the device in case the device is owned by some other component. When the host gains ownership on the device, the kernel can remove the RFKILL_HARD_BLOCK_NOT_OWNER reason and the hw rfkill state will be off. Then, the userspace can bring the device up and start normal operation. The rfkill_event structure is enlarged to include the additional byte, it is now 9 bytes long. Old user space will ask to read only 8 bytes so that the kernel can know not to feed them with more data. When the user space writes 8 bytes, new kernels will just read what is present in the file descriptor. This new byte is read only from the userspace standpoint anyway. If a new user space uses an old kernel, it'll ask to read 9 bytes but will get only 8, and it'll know that it didn't get the new state. When it'll write 9 bytes, the kernel will again ignore this new byte which is read only from the userspace standpoint. Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com> Link: https://lore.kernel.org/r/20201104134641.28816-1-emmanuel.grumbach@intel.com Signed-off-by: Johannes Berg <johannes.berg@intel.com> |
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| 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.