On Thu, Jun 29, 2017 at 08:50:32PM +0100, Alan Cox wrote: > So IMHO there are two cases > > 1. The configuration is fixed in the hardware - in which case we should > automatically set it in kernel, or from device tree. Right. > 2. The configuration is soft - in which case you need an ioctl you can > use on the port to change it - irrespective of whether sysfs also handles > it. For simple permissions reasons and also to avoid races you need that > ioctl. Ok, but if we are going to extend and use the RS485 ioctl for this, I think we should just stick to that and not add a sysfs-interface as well. I'll take a closer look at this. > We intentionally have lots of spare space left to extend the RS485 ioctl, > and we have termiox which contains even more room and historically in > other Unixen dealt with all sorts of weird and wonderful parameters used > on stuff like synchronous ports. Yes, your foresight when adding (generalising) that ioctl might come in handy now. :) Thanks, Johan -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
