On Thu, Nov 26, 2009 at 10:34:55PM -0500, Jon Smirl wrote: > On Thu, Nov 26, 2009 at 10:12 PM, Jarod Wilson <jarod@xxxxxxxxxxxx> wrote: > > This part... Not so wild about. The common thought I'm seeing from people is > > that we should be using setkeycode to load keymaps. I mean, sure, I suppose > > this could be abstracted away so the user never sees it, but it seems to be > > reinventing a way to set up key mapping when setkeycode already exists, and > > is used by a number of existing IR devices in the v4l/dvb subsystem (as well > > as misc things like the ati rf remotes, iirc). Is there some distinct > > advantage to going this route vs. setkeycode that I'm missing? > > The configfs scheme and keymaps offer the same abilities. One is an > ancient binary protocol and the other one uses Unix standard commands > like mkdir and echo to build the map. You need special commands - > setkeycodes, getkeycodes, showkey, loadkeys, xmodmap, dump-keys to use > a keymap. I've been using Linux forever and I can't remember how > these commands work. Nor you really should - it all is mostly being used transparently for the end-user. I mean udev loading your laptop-specific keymap is not using loadkeys but specially written utility that issues EVIOCSKEYCODE directly. > > Keymaps are a binary protocol written by Risto Kankkunen in 1993. > Configfs was added by Oracle about two years ago but it has not been > used for mapping purposes. Nor it is even enabled by default... Do we want to make in mandatory on all consumer systems out there? > > It's another discussion, but if IR goes the configfs route I'd > consider writing a patch to switch keymaps/keycodes onto the configfs > model. It is a huge advantage to get rid of these pointless special > purpose commands that nobody knows how to use. I'd keep the legacy > IOCTLs working and redirect the data structure to a configfs one > instead of the existing structure. What is the memory footprint for configfs solution though? I would hate to see the cost of user-modifiable keymap explode tenfold so that we can rely less (not even get rid of, since it is published userspace API/ABI) on setkeycodes and related ioctls. > > The same idea is behind getting rid of IOCTLs and using sysfs. Normal > Unix commands can manipulate sysfs. IOCTLs have problems with strace, > endianess and the size of int (32/64b). The size of long you mean, right? Besides, now that we know better we should simply use explicitely-sized fields in ioctl structures. -- Dmitry -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
