Hello Greg On Thu, Jun 11, 2015 at 4:31 PM, Greg KH <greg@xxxxxxxxx> wrote: > > real-time performance does not mean it has to be in the kernel at all. > > And almost no one needs "real" real-time performance, that's a horrible > check-box that people love to claim is needed and yet, almost no one > really needs in the end. > Agree, I do NOT need real time performace, in fact I can tolerate msecs of jitter. This is why I want to have a userland application >> By looking at our applications, The userspace sollution is more than >> enough for our requirements. >> >> The problem appears when we want to use the serial adapter. I want to >> keep using the serial API, but I cannot achieve this from userspace. > > I don't understand what type of API you are talking about here. What > exactly does ethercat do? What are you doing that does not work today > from userspace with the existing serial apis? Ehtercat is an industrial protocol that runs over ethernet. In a normal setup, there is one master and multiple slaves. Master is generally a PC, and the slaves are GPIO boards, serial ports, CAN bridges.... Ethercat is quite a complex protocol, it has a shared clock, device discovery.... So before you can read/write a register at a slave you end up with thousands of lines of code. What I want to do, is access a ethercat slave serial port like a "normal" serial port in my computer (/dev/ttyS0, /dev/ttyUSB0, /dev/ttyUL0....) That way any application can use the serial port with no modification. The common approach would be to create a serial port kernel module, but because it is such a complicated protocol I rather handle it in userland (same idea as uinput, but for serial ports) I am now taking a look to Bjørn suggestion about using a pty, and looks very promising. Thanks! -- Ricardo Ribalda _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
