Add a paragraph on how to package kernel modules

SVN-Revision: 6658
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Florian Fainelli 2007-03-24 10:18:36 +00:00
parent 9765f4032e
commit 1cd307f48b

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@ -39,7 +39,7 @@ with the latest compilers, latest kernels and latest applications.
So let's take a look at OpenWrt and see how this all works.
\subsubsection{Download openwrt}
\subsubsection{Download OpenWrt}
This article refers to the "Kamikaze" branch of OpenWrt, which can be downloaded via
subversion using the following command:
@ -373,6 +373,59 @@ After you have created your \texttt{package/\textit{<name>}/Makefile}, the new p
will automatically show in the menu the next time you run "make menuconfig" and if selected
will be built automatically the next time "\texttt{make}" is run.
\subsection{Creating kernel modules packages}
The OpenWrt distribution makes the distinction between two kind of kernel modules, those coming along with the mainline kernel, and the others available as a separate project. We will see later that a common template is used for both of them.
For kernel modules that are part of the mainline kernel source, the makefiles are located in \textit{package/kernel/modules/*.mk} and they appear under the section "Kernel modules"
For external kernel modules, you can add them to the build system just like if they were software packages by defining a KernelPackage section in the package makefile.
Here for instance the Makefile for the I2C subsytem kernel modules :
\begin{Verbatim}[frame=single,numbers=left]
#
# Copyright (C) 2006 OpenWrt.org
#
# This is free software, licensed under the GNU General Public License v2.
# See /LICENSE for more information.
#
# $Id $
I2CMENU:=I2C Bus
define KernelPackage/i2c-core
TITLE:=I2C support
DESCRIPTION:=Kernel modules for i2c support
SUBMENU:=$(I2CMENU)
KCONFIG:=$(CONFIG_I2C_CORE) \
$(CONFIG_I2C_DEV)
FILES:=$(MODULES_DIR)/kernel/drivers/i2c/*.$(LINUX_KMOD_SUFFIX)
AUTOLOAD:=$(call AutoLoad,50,i2c-core i2c-dev)
endef
$(eval $(call KernelPackage,i2c-core))
\end{Verbatim}
To group kernel modules under a common description in menuconfig, you might want to define a \textit{<description>MENU} variable on top of the kernel modules makefile.
\begin{itemize}
\item \texttt{TITLE} \\
The name of the module as seen via menuconfig
\item \texttt{DESCRIPTION} \\
The description as seen via help in menuconfig
\item \texttt{SUBMENU} \\
The sub menu under which this package will be seen
\item \texttt{KCONFIG} \\
Kernel configuration option dependency. For external modules, remove it.
\item \texttt{FILES} \\
Files you want to inlude to this kernel module package, separate with spaces.
\item \texttt{AUTOLOAD} \\
Modules that will be loaded automatically on boot, the order you write them is the order they would be loaded.
\end{itemize}
After you have created your \texttt{package/kernel/modules/\textit{<name>}.mk}, the new kernel modules package
will automatically show in the menu under "Kernel modules" next time you run "make menuconfig" and if selected
will be built automatically the next time "\texttt{make}" is run.
\subsection{Conventions}