README: Document kernel headers installation process

Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>

1 files changed, 17 insertions, 2 deletions

diff --git a/README b/README
index 71da2aa..71f9bcc 100644
--- a/README
+++ b/README
@@ -26,6 +26,22 @@ export PATH=/opt/scratchbox/compilers/cs2009q3-eglibc2.10-armv7-hard/bin:$PATH
 
 to ~/.bashrc (when using the bash shell).
 
+Kernel Headers
+--------------
+
+Due to the V4L2 events ABI breakages between kernels v3.0 and v3.1, you must
+make sure that the kernel headers used during compilation and the kernel running
+on the target system are both <= v3.0 or >= v3.1.
+
+To compile the applications against kernel headers from a kernel git tree you
+first need to pre-process the headers to make them usable in userspace. This can
+be done by running
+
+make ARCH=arm headers_install
+
+in the kernel source directory. The headers will be installed in the
+usr/include/ subdirectory of your kernel sources.
+
 Compilation
 ===========
 
@@ -33,5 +49,4 @@ To compile the ARM software, run
 
 make KDIR=/path/to/kernel/sources CROSS_COMPILE=arm-none-linux-gnueabi-
 
-This will create the ts binary for ARM.
-
+This will create the live and snapshot binaries for ARM.