I’m trying to use uart4 to program an arduino and I need to get DTR to work for that purpose (it resets the arduino). I see in the omap serial driver that there’s code there to map DTR to a gpio pin. E.g. see https://lkml.org/lkml/2012/7/29/149
As far as I can see this has indeed made it into the kernel (see http://lxr.free-electrons.com/source/drivers/tty/serial/omap-serial.c?v=3.8#L154), but I’m a bit at a loss about how to specify this in the DTC overlay. I’ve tried the following without much luck. Does anyone have an idea?
/ {
compatible = “ti,beaglebone”, “ti,beaglebone-black”;
part-number = “BB-UART4-TVE”;
version = “00A0”;
exclusive-use = “P9.13”, “P9.11”, “P9.15”, “P8.33”, “P8.35”, “uart4”;
fragment@0 {
target = <0xdeadbeef>;
overlay {
pinmux_bb_uart4_pins {
pinctrl-single,pins = <
0x070 0x26 /* P9_11 = GPIO0_30 = GPMC_WAIT0 , MODE6 /
0x074 0x06 / P9_13 = GPIO0_31 = GPMC_WPN, MODE6 /
0x040 0x0F / P9_15 = GPIO1_16 = GPIO48, MODE7 /
0x0D4 0x06 / P8_33 = UART4_RTSN = lcd_data13, MODE6 /
0x0D0 0x26 / P8_35 = UART4_CTSN = lcd_data12, MODE6 */
;
linux,phandle = <0x1>;
phandle = <0x1>;
};
};
};
fragment@1 {
target = <0xdeadbeef>;
overlay {
status = “okay”;
pinctrl-names = “default”;
pinctrl-0 = <0x1>;
dtr-gpio = <&gpio1 16 0>; /* 0=GPIO_ACTIVE_HIGH>;*/
};
};