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authorAaro Koskinen <aaro.koskinen@iki.fi>2016-01-23 23:37:17 +0300
committerGregory CLEMENT <gregory.clement@free-electrons.com>2016-02-09 13:00:25 +0300
commit39ac0979de635c8be94e1353afde65524ac1ed03 (patch)
tree1e690cfbb77c32c4e1383d759940836f6a6fa95b /arch
parent60ff189ca05dedac97af8d9e51c285a44bc9e5a5 (diff)
downloadlinux-39ac0979de635c8be94e1353afde65524ac1ed03.tar.xz
ARM: dts: kirkwood: provide template for RS-232/485 configuration for OpenRD
Some OpenRD boards have RS-232 and RS-486 connectors wired, but using them needs a custom DTB as the current DTB configures SD card slot instead. This patch adds documentation into the DTS on how to change the configuration. Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/arm/boot/dts/kirkwood-openrd.dtsi31
1 files changed, 30 insertions, 1 deletions
diff --git a/arch/arm/boot/dts/kirkwood-openrd.dtsi b/arch/arm/boot/dts/kirkwood-openrd.dtsi
index f65b7273bb0a..24f1d30970a0 100644
--- a/arch/arm/boot/dts/kirkwood-openrd.dtsi
+++ b/arch/arm/boot/dts/kirkwood-openrd.dtsi
@@ -40,7 +40,7 @@
pinctrl-0 = <&pmx_select28 &pmx_sdio_cd &pmx_select34>;
pinctrl-names = "default";
- pmx_select28: pmx-select-rs232-rs484 {
+ pmx_select28: pmx-select-rs232-rs485 {
marvell,pins = "mpp28";
marvell,function = "gpio";
};
@@ -65,10 +65,39 @@
status = "okay";
cd-gpios = <&gpio0 29 9>;
};
+ gpio@10100 {
+ p28 {
+ gpio-hog;
+ gpios = <28 GPIO_ACTIVE_HIGH>;
+ /*
+ * SelRS232or485 selects between RS-232 or RS-485
+ * mode for the second UART.
+ *
+ * Low: RS-232
+ * High: RS-485
+ *
+ * To use the second UART, you need to change also
+ * the SelUARTorSD.
+ */
+ output-low;
+ line-name = "SelRS232or485";
+ };
+ };
gpio@10140 {
p2 {
gpio-hog;
gpios = <2 GPIO_ACTIVE_HIGH>;
+ /*
+ * SelUARTorSD selects between the second UART
+ * (serial@12100) and SD (mvsdio@90000).
+ *
+ * Low: UART
+ * High: SD
+ *
+ * When changing this line make sure the newly
+ * selected device node is enabled and the
+ * previously selected device node is disabled.
+ */
output-high; /* Select SD by default */
line-name = "SelUARTorSD";
};