Hello, On Thu, 18 Feb 2021 06:55:53 +0300 Alexander Shiyan <shc_work@xxxxxxx> wrote: > I wrote a little inaccurately, I did not mean a physical interface RS-485, > but rather a time-critical MODBUS protocol. (In our case it used on top on RS-485). OK, so it's not about 232 vs 485. > I do not know how best to solve this problem, it may be an additional parameter > for the devicetree, but in this case it is not clear how to manage it if the > devicetree is not used ... No, it cannot be a parameter in the Device Tree, as what we're talking about is not hardware description, but configuration of the hardware for particular use cases. > This could be a Kconfig item (but something's not very good either). > Probably the best solution is to adapt some kind of IOCTL (or control via SYSFS). Greg, Jiri, perhaps you could comment on what would be the appropriate user-space interface to use or add to be able to configure such aspects of a UART controller ? Thomas -- Thomas Petazzoni, CTO, Bootlin Embedded Linux and Kernel engineering https://bootlin.com
