On Sun, Dec 02, 2012 at 07:26:27PM +0200, Eli Billauer wrote: > On 11/30/2012 06:32 PM, Greg KH wrote: > >>>>> >>+static struct class *xillybus_class; > >>>> >Why not just use the misc interface instead of your own class? > >>> When Xillybus is used, the whole system's mission is usually around > >>> it (e.g. it's a computer doing data acquisition through the Xillybus > >>> pipes). So giving it a high profile makes sense, I believe. Besides, > >>> a dozen of device files are not rare. > >It is no problem to create dozens of misc devices. It makes your driver > >smaller, contain less code that I have to audit and you have to ensure > >you got right, and it removes another user of 'struct class' which we > >are trying to get rid of anyway. So please, move to use a misc device. > > > > It has just occurred to me that DYNAMIC_MINORS is 64 > (drivers/char/misc.c), so I guess that limits the number of misc > devices that can be generated, at least with dynamically allocated > minors. I previously mentioned "a dozen" as the number of devices, > but I've already run tests with 100+ devices, and I can also think > of a sane application for that. > > > So if I understood the situation correctly, it looks like using misc > devices will create a limitation which will be reached sooner or > later. > > Any suggestion what to do?
Given that I don't really understand how you can have that many device nodes, because I don't know what they all seem to be needed for, I can't answer this question. Again, any hints on the user/kernel api you use/need here? Does it really have to be device nodes? What's wrong with the simple firmware interface the kernel provides? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
