On Thursday 14 April 2016 14:13:19 Geert Uytterhoeven wrote: > Document a set of generic properties for describing UARTs in a > device tree: > 1. The GPIO modem control properties are currently duplicated across > hardware-specific binding documentation, > 2. The property for dedicated RTS/CTS hardware flow control lines is > already supported by several drivers, albeit with a vendor-specific > prefix, hence make it generic. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> Originally the ISA 8250 uart binding (from ieee) was used as the template for other uart bindings. How about documenting the parts that are used in 8250-of today (current-speed, clock-frequency, reg-offset, reg-shift, fifo-size, reg-io-width, auto-flow-control) in the same file? > - out1-gpios: Must contain a GPIO specifier, referring to the GPIO pin to be > used as the UART's OUT1 line. > - out2-gpios: Must contain a GPIO specifier, referring to the GPIO pin to be > used as the UART's OUT2 line. I had to look up what OUT1 and OUT2 are, but I still don't see how you'd implement them using a GPIO line: From all I can tell, these are usually internal registers in a hardware uart but they are not assigned to an external line on the standard db9 or even the old db25 connectors. Should we drop these instead? On a related note, do you think it would be possible to do a bit-banged uart if we defined gpio lines for rxd and txd? Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
