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Hans de Goede 29ec3394f0 brcmfmac: Fix ccode from EFI nvram when necessary
In some cases the EFI-var stored nvram contains "ccode=ALL" or "ccode=XV"
to specify "worldwide" compatible settings, but these 2 ccode-s do not work
properly.

I've tested the different known "worldwide" ccode-s used in various nvram
sources with the latest firmwares from linux-firmware for various brcmfmac
models, here is a simplified (*) table with what each setting results in:

ALL: 12-14 disab, U-NII-1, U-NII-2 no-IR/radar, U-NII-3
XV:  12-14 no-IR, disables all 5G channels
XY:  12-13 enab, 14 disab, U-NII-1 enab, U-NII-2 no-IR/radar, U-NII-3 disab
X2:  12-13 no-IR, 14 dis, U-NII-1 no-IR, U-NII-2 no-IR/radar, U-NII-3 no-IR

Where 12,13,14 are 2.4G channels 12-14 and U-NII-1/2/3 are the 3 different
5G channel groups. no-IR is no-Initiate-Radiation, we will never send on
these channels without first having received valid wifi traffic there.

This immediately shows that both ALL and XV are not as worldwide as we want
them to be. ALL causes channels 12 and 13 to not be available and XV causes
all 5GHz channels to not be available. Also ALL unconditionally enables the
U-NII-1 and U-NII-3 5G groups, while we really should be using no-IR for
these.

This commit replace XV and ALL with X2, which allows usage of chan 12-13
and 5G channels, but only after receiving valid wifi traffic there first.

Note that this configure the firmware's channel limits, the kernels own
regulatory restrictions based on e.g. regulatory info received from the
access-point, will be applied on top of this.

This fixes channels 12+13 not working on the Asus T200TA and the Lenovo
Mixx 2 8 and 5G channels not working on the Asus T100HA.

This has been tested on the following models: Acer Iconia Tab8 w1-810,
Acer One 10, Asus T100CHI, Asus T100HA, Asus T100TA, Asus T200TA and a
Lenovo Mixx 2 8.

*) There are some exceptions to this table:
1) On really old firmware e.g. linux-firmware's 2011 brcmfmac4330-sdio.bin
   ALL really means all, unconditionally enabling everything
2) The exact meaning might be influenced by setting the regrev nvram var.
   Specifically using ccode=XV + regrev=1 on brcmfmac43241b4 leads to:
   12-14 no-ir, U-NII-1 no-ir, U-NII-2 no-ir/radar, U-NII-3 no-ir
   But only on the brcmfmac43241b4 and not on e.g. the brcmfmac43340

Tested-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
2018-11-06 18:51:41 +02:00
arch Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-11-03 18:25:17 -07:00
block for-linus-20181102 2018-11-02 11:25:48 -07:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto KEYS: asym_tpm: Add support for the sign operation [ver #2] 2018-10-26 09:30:47 +01:00
Documentation This pull request contains updates for UBIFS: 2018-11-04 14:46:04 -08:00
drivers brcmfmac: Fix ccode from EFI nvram when necessary 2018-11-06 18:51:41 +02:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs This pull request contains updates for UBIFS: 2018-11-04 14:46:04 -08:00
include NFS client bugfixes for Linux 4.20 2018-11-04 08:20:09 -08:00
init memblock: stop using implicit alignment to SMP_CACHE_BYTES 2018-10-31 08:54:16 -07:00
ipc ipc: IPCMNI limit check for semmni 2018-10-31 08:54:14 -07:00
kernel Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-11-03 18:37:09 -07:00
lib Merge branch 'work.afs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2018-11-01 19:58:52 -07:00
LICENSES This is a fairly typical cycle for documentation. There's some welcome 2018-10-24 18:01:11 +01:00
mm memory_hotplug: cond_resched in __remove_pages 2018-11-03 10:09:38 -07:00
net NFS client bugfixes for Linux 4.20 2018-11-04 08:20:09 -08:00
samples VFIO updates for v4.20 2018-10-31 11:01:38 -07:00
scripts Kbuild updates for v4.20 (2nd) 2018-11-03 10:47:33 -07:00
security + Features/Improvements 2018-11-02 10:04:26 -07:00
sound sound fixes for 4.20-rc1 2018-11-02 11:02:52 -07:00
tools Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-11-03 18:25:17 -07:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt Revert "mm, mmu_notifier: annotate mmu notifiers with blockable invalidate callbacks" 2018-10-26 16:25:19 -07:00
.clang-format page cache: Convert find_get_pages_contig to XArray 2018-10-21 10:46:34 -04:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore Add hch to .get_maintainer.ignore 2015-08-21 14:30:10 -07:00
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap .mailmap: add Oleksij Rempel 2018-10-31 08:54:12 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS The Compiler Attributes series 2018-11-01 18:34:46 -07:00
Makefile Linux 4.20-rc1 2018-11-04 15:37:52 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

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.