diff options
| author | Geert Uytterhoeven <geert+renesas@glider.be> | 2016-04-22 17:22:20 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-04-30 09:26:55 -0700 |
| commit | 8d21f24416719198c860009210a5fa9b33487211 (patch) | |
| tree | cfe9aa0a83e327e5368ea3d6ecbcefd5bbeda67c /Documentation/devicetree/bindings/serial/serial.txt | |
| parent | 28264eb6c36e267aad0e6cfb353ad1e7920ac87b (diff) | |
doc: DT: Add Generic Serial Device Tree Bindings
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@glider.be>
Acked-by: Rob Herring <rob@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'Documentation/devicetree/bindings/serial/serial.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/serial/serial.txt | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/serial/serial.txt b/Documentation/devicetree/bindings/serial/serial.txt new file mode 100644 index 000000000000..fd970f76a7b8 --- /dev/null +++ b/Documentation/devicetree/bindings/serial/serial.txt @@ -0,0 +1,57 @@ +Generic Serial DT Bindings + +This document lists a set of generic properties for describing UARTs in a +device tree. Whether these properties apply to a particular device depends on +the DT bindings for the actual device. + +Optional properties: + - cts-gpios: Must contain a GPIO specifier, referring to the GPIO pin to be + used as the UART's CTS line. + - dcd-gpios: Must contain a GPIO specifier, referring to the GPIO pin to be + used as the UART's DCD line. + - dsr-gpios: Must contain a GPIO specifier, referring to the GPIO pin to be + used as the UART's DSR line. + - dtr-gpios: Must contain a GPIO specifier, referring to the GPIO pin to be + used as the UART's DTR line. + - rng-gpios: Must contain a GPIO specifier, referring to the GPIO pin to be + used as the UART's RNG line. + - rts-gpios: Must contain a GPIO specifier, referring to the GPIO pin to be + used as the UART's RTS line. + + - uart-has-rtscts: The presence of this property indicates that the + UART has dedicated lines for RTS/CTS hardware flow control, and that + they are available for use (wired and enabled by pinmux configuration). + This depends on both the UART hardware and the board wiring. + Note that this property is mutually-exclusive with "cts-gpios" and + "rts-gpios" above. + + +Examples: + + uart1: serial@48022000 { + compatible = "ti,am3352-uart", "ti,omap3-uart"; + ti,hwmods = "uart2"; + clock-frequency = <48000000>; + reg = <0x48022000 0x2000>; + interrupts = <73>; + dmas = <&edma 28 0>, <&edma 29 0>; + dma-names = "tx", "rx"; + dtr-gpios = <&gpio2 22 GPIO_ACTIVE_LOW>; + dsr-gpios = <&gpio2 23 GPIO_ACTIVE_LOW>; + dcd-gpios = <&gpio2 24 GPIO_ACTIVE_LOW>; + rng-gpios = <&gpio2 25 GPIO_ACTIVE_LOW>; + cts-gpios = <&gpio0 12 GPIO_ACTIVE_LOW>; + rts-gpios = <&gpio0 13 GPIO_ACTIVE_LOW>; + status = "okay"; + }; + + scifa4: serial@e6c80000 { + compatible = "renesas,scifa-sh73a0", "renesas,scifa"; + reg = <0xe6c80000 0x100>; + interrupts = <GIC_SPI 78 IRQ_TYPE_LEVEL_HIGH>; + clocks = <&mstp2_clks SH73A0_CLK_SCIFA4>; + clock-names = "fck"; + power-domains = <&pd_a3sp>; + uart-has-rtscts; + status = "okay"; + }; |