On Wed, 3 Oct 2012 19:07:31 +0200, Baruch Siach wrote: > I think that a template driver in the mainline kernel would be a great > contribution to the kernel.
On my side, I am questioning whether this is a goal that can actually be achieved. In practice, Constantine driver will never be useful as a template for any driver, for two main reasons: * It is only showing how to write a raw character driver, while most drivers in the kernel are integrated inside an existing subsystem, that requires the implementation of subsystem-specific APIs (tty subsystem, mtd subsystem, input subsystem, network subsystem, etc.). Therefore, each of those subsystems would require a separate template driver. And in fact some of them already have such a template, see for example http://lxr.free-electrons.com/source/drivers/video/skeletonfb.c for the framebuffer subsystem. Doing similar skeleton drivers for each subsystem would most likely be a lot more useful. * This driver only shows how to implement a platform driver, while only some of the drivers are platform drivers. Many other are I2C drivers, SPI drivers, USB drivers, PCI drivers, etc. and therefore this template does not show any of this. Another example is that this driver is a platform driver, but does not support the Device Tree, which is needed on ARM, PowerPC, Microblaze and probably at least another architecture. Therefore the whole idea of writing a "generic template kernel driver" is doomed to fail, as it is simply not possible. Also, /proc entries are deprecated for drivers. No new driver should create one. Use debugfs instead for debugging features, or possibly sysfs if this is actually relevant. Best regards, Thomas -- Thomas Petazzoni, Free Electrons Kernel, drivers, real-time and embedded Linux development, consulting, training and support. http://free-electrons.com _______________________________________________ Celinux-dev mailing list Celinux-dev@lists.celinuxforum.org https://lists.celinuxforum.org/mailman/listinfo/celinux-dev
