diff options
Diffstat (limited to 'doc')
| -rw-r--r-- | doc/device-tree-bindings/serial/8250.txt | 66 | ||||
| -rw-r--r-- | doc/device-tree-bindings/serial/ns16550.txt | 10 | ||||
| -rw-r--r-- | doc/device-tree-bindings/serial/omap_serial.txt | 33 | ||||
| -rw-r--r-- | doc/device-tree-bindings/serial/snps-dw-apb-uart.txt | 76 |
4 files changed, 175 insertions, 10 deletions
diff --git a/doc/device-tree-bindings/serial/8250.txt b/doc/device-tree-bindings/serial/8250.txt new file mode 100644 index 0000000..91d5ab0 --- /dev/null +++ b/doc/device-tree-bindings/serial/8250.txt @@ -0,0 +1,66 @@ +* UART (Universal Asynchronous Receiver/Transmitter) + +Required properties: +- compatible : one of: + - "ns8250" + - "ns16450" + - "ns16550a" + - "ns16550" + - "ns16750" + - "ns16850" + - For Tegra20, must contain "nvidia,tegra20-uart" + - For other Tegra, must contain '"nvidia,<chip>-uart", + "nvidia,tegra20-uart"' where <chip> is tegra30, tegra114, tegra124, + tegra132, or tegra210. + - "nxp,lpc3220-uart" + - "ralink,rt2880-uart" + - "ibm,qpace-nwp-serial" + - "altr,16550-FIFO32" + - "altr,16550-FIFO64" + - "altr,16550-FIFO128" + - "fsl,16550-FIFO64" + - "fsl,ns16550" + - "serial" if the port type is unknown. +- reg : offset and length of the register set for the device. +- interrupts : should contain uart interrupt. +- clock-frequency : the input clock frequency for the UART + or + clocks phandle to refer to the clk used as per Documentation/devicetree + /bindings/clock/clock-bindings.txt + +Optional properties: +- current-speed : the current active speed of the UART. +- reg-offset : offset to apply to the mapbase from the start of the registers. +- reg-shift : quantity to shift the register offsets by. +- reg-io-width : the size (in bytes) of the IO accesses that should be + performed on the device. There are some systems that require 32-bit + accesses to the UART (e.g. TI davinci). +- used-by-rtas : set to indicate that the port is in use by the OpenFirmware + RTAS and should not be registered. +- no-loopback-test: set to indicate that the port does not implements loopback + test mode +- fifo-size: the fifo size of the UART. +- auto-flow-control: one way to enable automatic flow control support. The + driver is allowed to detect support for the capability even without this + property. + +Note: +* fsl,ns16550: + ------------ + Freescale DUART is very similar to the PC16552D (and to a + pair of NS16550A), albeit with some nonstandard behavior such as + erratum A-004737 (relating to incorrect BRK handling). + + Represents a single port that is compatible with the DUART found + on many Freescale chips (examples include mpc8349, mpc8548, + mpc8641d, p4080 and ls2085a). + +Example: + + uart@80230000 { + compatible = "ns8250"; + reg = <0x80230000 0x100>; + clock-frequency = <3686400>; + interrupts = <10>; + reg-shift = <2>; + }; diff --git a/doc/device-tree-bindings/serial/ns16550.txt b/doc/device-tree-bindings/serial/ns16550.txt deleted file mode 100644 index ef0b9ae..0000000 --- a/doc/device-tree-bindings/serial/ns16550.txt +++ /dev/null @@ -1,10 +0,0 @@ -NS16550 UART - -This UART driver supports many chip variants and is used in mamy SoCs. - -Required properties: -- compatible: "ns16550" or "nvidia,tegra20-uart" -- reg: start address and size of registers -- reg-shift: shift value indicating register size: 0=byte, 1=16bit,2=32bit etc. -- clock-frequency: input clock frequency for the UART (used to calculate the - baud rate divisor) diff --git a/doc/device-tree-bindings/serial/omap_serial.txt b/doc/device-tree-bindings/serial/omap_serial.txt new file mode 100644 index 0000000..7a71b5d --- /dev/null +++ b/doc/device-tree-bindings/serial/omap_serial.txt @@ -0,0 +1,33 @@ +OMAP UART controller + +Required properties: +- compatible : should be "ti,omap2-uart" for OMAP2 controllers +- compatible : should be "ti,omap3-uart" for OMAP3 controllers +- compatible : should be "ti,omap4-uart" for OMAP4 controllers +- compatible : should be "ti,am4372-uart" for AM437x controllers +- compatible : should be "ti,am3352-uart" for AM335x controllers +- compatible : should be "ti,dra742-uart" for DRA7x controllers +- reg : address and length of the register space +- interrupts or interrupts-extended : Should contain the uart interrupt + specifier or both the interrupt + controller phandle and interrupt + specifier. +- ti,hwmods : Must be "uart<n>", n being the instance number (1-based) + +Optional properties: +- clock-frequency : frequency of the clock input to the UART +- dmas : DMA specifier, consisting of a phandle to the DMA controller + node and a DMA channel number. +- dma-names : "rx" for receive channel, "tx" for transmit channel. + +Example: + + uart4: serial@49042000 { + compatible = "ti,omap3-uart"; + reg = <0x49042000 0x400>; + interrupts = <80>; + dmas = <&sdma 81 &sdma 82>; + dma-names = "tx", "rx"; + ti,hwmods = "uart4"; + clock-frequency = <48000000>; + }; diff --git a/doc/device-tree-bindings/serial/snps-dw-apb-uart.txt b/doc/device-tree-bindings/serial/snps-dw-apb-uart.txt new file mode 100644 index 0000000..12bbe9f --- /dev/null +++ b/doc/device-tree-bindings/serial/snps-dw-apb-uart.txt @@ -0,0 +1,76 @@ +* Synopsys DesignWare ABP UART + +Required properties: +- compatible : "snps,dw-apb-uart" +- reg : offset and length of the register set for the device. +- interrupts : should contain uart interrupt. + +Clock handling: +The clock rate of the input clock needs to be supplied by one of +- clock-frequency : the input clock frequency for the UART. +- clocks : phandle to the input clock + +The supplying peripheral clock can also be handled, needing a second property +- clock-names: tuple listing input clock names. + Required elements: "baudclk", "apb_pclk" + +Optional properties: +- snps,uart-16550-compatible : reflects the value of UART_16550_COMPATIBLE + configuration parameter. Define this if your UART does not implement the busy + functionality. +- resets : phandle to the parent reset controller. +- reg-shift : quantity to shift the register offsets by. If this property is + not present then the register offsets are not shifted. +- reg-io-width : the size (in bytes) of the IO accesses that should be + performed on the device. If this property is not present then single byte + accesses are used. +- dcd-override : Override the DCD modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- dsr-override : Override the DTS modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- cts-override : Override the CTS modem status signal. This signal will always + be reported as active instead of being obtained from the modem status + register. Define this if your serial port does not use this pin. +- ri-override : Override the RI modem status signal. This signal will always be + reported as inactive instead of being obtained from the modem status register. + Define this if your serial port does not use this pin. + +Example: + + uart@80230000 { + compatible = "snps,dw-apb-uart"; + reg = <0x80230000 0x100>; + clock-frequency = <3686400>; + interrupts = <10>; + reg-shift = <2>; + reg-io-width = <4>; + dcd-override; + dsr-override; + cts-override; + ri-override; + }; + +Example with one clock: + + uart@80230000 { + compatible = "snps,dw-apb-uart"; + reg = <0x80230000 0x100>; + clocks = <&baudclk>; + interrupts = <10>; + reg-shift = <2>; + reg-io-width = <4>; + }; + +Example with two clocks: + + uart@80230000 { + compatible = "snps,dw-apb-uart"; + reg = <0x80230000 0x100>; + clocks = <&baudclk>, <&apb_pclk>; + clock-names = "baudclk", "apb_pclk"; + interrupts = <10>; + reg-shift = <2>; + reg-io-width = <4>; + }; |