wireless: support internal statically compiled regulatory database

This patch provides infrastructure for machine translation of the
regulatory rules database used by CRDA into a C data structure.
It includes code for searching that database as an alternative
to dynamic regulatory rules updates via CRDA.  Most people should
use CRDA instead of this infrastructure, but it provides a better
alternative than the WIRELESS_OLD_REGULATORY infrastructure (which
can now be removed).

Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 24 insertions, 0 deletions

diff --git a/Documentation/networking/regulatory.txt b/Documentation/networking/regulatory.txt
index ee31369e9e5..9551622d0a7 100644
--- a/Documentation/networking/regulatory.txt
+++ b/Documentation/networking/regulatory.txt
@@ -188,3 +188,27 @@ Then in some part of your code after your wiphy has been registered:
 		       &mydriver_jp_regdom.reg_rules[i],
 		       sizeof(struct ieee80211_reg_rule));
 	regulatory_struct_hint(rd);
+
+Statically compiled regulatory database
+---------------------------------------
+
+In most situations the userland solution using CRDA as described
+above is the preferred solution.  However in some cases a set of
+rules built into the kernel itself may be desirable.  To account
+for this situation, a configuration option has been provided
+(i.e. CONFIG_CFG80211_INTERNAL_REGDB).  With this option enabled,
+the wireless database information contained in net/wireless/db.txt is
+used to generate a data structure encoded in net/wireless/regdb.c.
+That option also enables code in net/wireless/reg.c which queries
+the data in regdb.c as an alternative to using CRDA.
+
+The file net/wireless/db.txt should be kept up-to-date with the db.txt
+file available in the git repository here:
+
+    git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-regdb.git
+
+Again, most users in most situations should be using the CRDA package
+provided with their distribution, and in most other situations users
+should be building and using CRDA on their own rather than using
+this option.  If you are not absolutely sure that you should be using
+CONFIG_CFG80211_INTERNAL_REGDB then _DO_NOT_USE_IT_.