Hi Andrey, +Cc NeilBrown <neil@xxxxxxxxxx> On Mon, Nov 16, 2015 at 07:24:58PM +0300, Andrey Vostrikov wrote: > Hi, > > I have an embedded system with microcontroller connected via > UART/RS232 port. This microcontroller implements several low-level > functions that need to be exposed as device drivers in other > subsystems (watchdog, LEDs, HWMON, firmware read/write). > > I checked many drivers implemented in the kernel, searched through > mail list archives and it looks like there are three different ways to > solve this task: > A) most of the devices that are connected using UART have user space > program that configures and manages it (either directly or with help > of dedicated line discipline, SLIP, SL-CAN, etc) > B) serio - mostly used for input devices > C) direct use of UART port taking control from serial_core. > > The best match I have found so far is MFD driver for Atmel > Microcontroller on iPaq h3xxx (drivers/mfd/ipaq-micro.c) that follows > concept "C)" There's also D) TTY slave device support: https://lkml.org/lkml/2015/3/18/40 Unfortunately this hasn't made it to mainline yet and it seems the parties lost interest after some lengthy discussion of device tree phandles vs. subnodes, but I think this is what you're looking for. Sascha -- Pengutronix e.K. | | Industrial Linux Solutions | http://www.pengutronix.de/ | Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | -- To unsubscribe from this list: send the line "unsubscribe linux-embedded" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
