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-rw-r--r--doc/device-tree-bindings/serial/8250.txt66
-rw-r--r--doc/device-tree-bindings/serial/ns16550.txt10
-rw-r--r--doc/device-tree-bindings/serial/omap_serial.txt33
-rw-r--r--doc/device-tree-bindings/serial/snps-dw-apb-uart.txt76
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>;
+ };