From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann E. MORIN Date: Fri, 26 Dec 2014 15:51:28 +0100 Subject: [Buildroot] building fbtft framebuffer drivers into buildroot. In-Reply-To: <20141226150438.08e429c2@free-electrons.com> References: <20141226102028.GA3982@free.fr> <20141226150438.08e429c2@free-electrons.com> Message-ID: <20141226145128.GC3982@free.fr> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: buildroot@busybox.net On 2014-12-26 15:04 +0100, Thomas Petazzoni spake thusly: > Dear Yann E. MORIN, > > On Fri, 26 Dec 2014 11:20:29 +0100, Yann E. MORIN wrote: > > > I've had a look at this package, and unfortunately, it will be hard to > > get it packaged in Buildroot. > > > > The problem is that this kernel module does not compile as an > > out-of-tree module, and their buildsystem is made so that it requires > > the kernel be patched. > > > > This is not posible with Buildroot. > > Well, yes and no. Indeed it is much easier to package if the stuff can > be built as an out-of-tree module. However, we have two examples of > things packaged in Buildroot that require patching the kernel: Xenomai > and RTAI. They use a loosely defined model that we could name "Linux > extension", see linux/linux-ext-*.mk. They basically hook up into the > Linux build process by adding some stuff to LINUX_PRE_PATCH_HOOKS. > > I recently had a look at the aufs stuff, and it has the same problem: > not only it is made of modules that can be built out-of-tree, but it > also needs to patch the kernel (some core VFS changes). > > So, I haven't looked at all the fbtft stuff. If it's a set of > standalone drivers that don't require any modification to the core of > the kernel, then indeed, turning them into out-of-tree modules can be a > good idea. If not, then using the "linux-ext" model can be a solution. Yes, I know about those linux "extensions". But the fact is that fbtft is only an additional modules with no impact on the core of the kernel; it requires "patching" the kernel just because it wants to add a Kconfig option and a Kbuild sub-directory. So, it would better be built as an out-of-tree module, rather than be handled as a kernel extension. Hence the reason I said it would not play well "as-is" with Buildroot. Regards, Yann E. MORIN. -- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | +33 662 376 056 | Software Designer | \ / CAMPAIGN | ___ | | +33 223 225 172 `------------.-------: X AGAINST | \e/ There is no | | http://ymorin.is-a-geek.org/ | _/*\_ | / \ HTML MAIL | v conspiracy. | '------------------------------^-------^------------------^--------------------'