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authorLinus Torvalds <torvalds@linux-foundation.org>2016-03-15 20:23:13 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2016-03-15 20:23:13 -0700
commit5ca5446ec5ba5e79a6f271cd026bb153d6850fcc (patch)
treeba6b9a309d5f8730a01002db389e05ea7f784f9c /Documentation
parent710d60cbf1b312a8075a2158cbfbbd9c66132dcc (diff)
parent3c177a166253653bf9c377eb28a5155ea2d9b631 (diff)
Merge tag 'pinctrl-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pin control updates from Linus Walleij: "An almost purely driver related set of changes with no major changes to the framework, only one patch adding an unlocked version of the pinctrl_find_gpio_range_from_pin() library call. New drivers: - ST Microelectronics STM32 MCU support: this is a non-MMU low-end platform for IoT things (etc). - Microchip PIC32 MCU support: same story as for STM32. New subdrivers: - Allwinner SunXi H3 R_PIO controller support. - Qualcomm IPQ4019 support. - MediaTek MT2701 and MT7623. - Allwinner A64 Non-critical fixes: - gpio_disable_free() for the Vybrid. - pinctrl single: use a separate lockdep class. Misc: - Substantial cleanups and rewrites for the Super-H PFC driver and subdrivers. - Various fixes and cleanups, especially Paul Gortmakers work to make nonmodular drivers nonmodular" * tag 'pinctrl-v4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (75 commits) pinctrl: single: Use a separate lockdep class drivers: pinctrl: add driver for Allwinner A64 SoC pinctrl: Broadcom Northstar2 pinctrl device tree bindings pinctrl: amlogic: Make driver independent from two-domain configuration pinctrl: amlogic: Separate some pin functions for Meson8 / Meson8b pinctrl: at91: use __maybe_unused to hide pm functions pinctrl: sh-pfc: core: don't open code of_device_get_match_data() pinctrl: uniphier: rename CONFIG options and file names pinctrl: sunxi: make A80 explicitly non-modular pinctrl: stm32: make explicitly non-modular pinctrl: sh-pfc: make explicitly non-modular pinctrl: meson: make explicitly non-modular pinctrl: pinctrl-mt6397 driver explicitly non-modular pinctrl: sunxi: does not need module.h pinctrl: pxa2xx: export symbols pinctrl: sunxi: Change mux setting on PI irq pins pinctrl: sunxi: Remove non existing irq's pinctrl: imx: attach iomuxc device to gpr syscon pinctrl-bcm2835: Fix cut-and-paste error in "pull" parsing pinctrl: lpc1850-scu: document nxp,gpio-pin-interrupt ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/gpio/microchip,pic32-gpio.txt49
-rw-r--r--Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt2
-rw-r--r--Documentation/devicetree/bindings/pinctrl/brcm,ns2-pinmux.txt102
-rw-r--r--Documentation/devicetree/bindings/pinctrl/microchip,pic32-pinctrl.txt60
-rw-r--r--Documentation/devicetree/bindings/pinctrl/nxp,lpc1850-scu.txt14
-rw-r--r--Documentation/devicetree/bindings/pinctrl/pinctrl-mt65xx.txt1
-rw-r--r--Documentation/devicetree/bindings/pinctrl/qcom,ipq4019-pinctrl.txt74
-rw-r--r--Documentation/devicetree/bindings/pinctrl/rockchip,pinctrl.txt2
-rw-r--r--Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt126
9 files changed, 429 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/gpio/microchip,pic32-gpio.txt b/Documentation/devicetree/bindings/gpio/microchip,pic32-gpio.txt
new file mode 100644
index 000000000000..ef3752889496
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/microchip,pic32-gpio.txt
@@ -0,0 +1,49 @@
+* Microchip PIC32 GPIO devices (PIO).
+
+Required properties:
+ - compatible: "microchip,pic32mzda-gpio"
+ - reg: Base address and length for the device.
+ - interrupts: The port interrupt shared by all pins.
+ - gpio-controller: Marks the port as GPIO controller.
+ - #gpio-cells: Two. The first cell is the pin number and
+ the second cell is used to specify the gpio polarity as defined in
+ defined in <dt-bindings/gpio/gpio.h>:
+ 0 = GPIO_ACTIVE_HIGH
+ 1 = GPIO_ACTIVE_LOW
+ 2 = GPIO_OPEN_DRAIN
+ - interrupt-controller: Marks the device node as an interrupt controller.
+ - #interrupt-cells: Two. The first cell is the GPIO number and second cell
+ is used to specify the trigger type as defined in
+ <dt-bindings/interrupt-controller/irq.h>:
+ IRQ_TYPE_EDGE_RISING
+ IRQ_TYPE_EDGE_FALLING
+ IRQ_TYPE_EDGE_BOTH
+ - clocks: Clock specifier (see clock bindings for details).
+ - microchip,gpio-bank: Specifies which bank a controller owns.
+ - gpio-ranges: Interaction with the PINCTRL subsystem.
+
+Example:
+
+/* PORTA */
+gpio0: gpio0@1f860000 {
+ compatible = "microchip,pic32mzda-gpio";
+ reg = <0x1f860000 0x100>;
+ interrupts = <118 IRQ_TYPE_LEVEL_HIGH>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ clocks = <&PBCLK4>;
+ microchip,gpio-bank = <0>;
+ gpio-ranges = <&pic32_pinctrl 0 0 16>;
+};
+
+keys {
+ ...
+
+ button@sw1 {
+ label = "ESC";
+ linux,code = <1>;
+ gpios = <&gpio0 12 0>;
+ };
+};
diff --git a/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt
index 9213b27e1036..69617220c5d6 100644
--- a/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/allwinner,sunxi-pinctrl.txt
@@ -21,6 +21,8 @@ Required properties:
"allwinner,sun9i-a80-r-pinctrl"
"allwinner,sun8i-a83t-pinctrl"
"allwinner,sun8i-h3-pinctrl"
+ "allwinner,sun8i-h3-r-pinctrl"
+ "allwinner,sun50i-a64-pinctrl"
- reg: Should contain the register physical address and length for the
pin controller.
diff --git a/Documentation/devicetree/bindings/pinctrl/brcm,ns2-pinmux.txt b/Documentation/devicetree/bindings/pinctrl/brcm,ns2-pinmux.txt
new file mode 100644
index 000000000000..e295dda4bbba
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/brcm,ns2-pinmux.txt
@@ -0,0 +1,102 @@
+Broadcom Northstar2 IOMUX Controller
+
+The Northstar2 IOMUX controller supports group based mux configuration. There
+are some individual pins that support modifying the pinconf parameters.
+
+Required properties:
+
+- compatible:
+ Must be "brcm,ns2-pinmux"
+
+- reg:
+ Define the base and range of the I/O address space that contains the
+ Northstar2 IOMUX and pin configuration registers.
+
+Properties in sub nodes:
+
+- function:
+ The mux function to select
+
+- groups:
+ The list of groups to select with a given function
+
+- pins:
+ List of pin names to change configuration
+
+The generic properties bias-disable, bias-pull-down, bias-pull-up,
+drive-strength, slew-rate, input-enable, input-disable are supported
+for some individual pins listed at the end.
+
+For more details, refer to
+Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
+
+For example:
+
+ pinctrl: pinctrl@6501d130 {
+ compatible = "brcm,ns2-pinmux";
+ reg = <0x6501d130 0x08>,
+ <0x660a0028 0x04>,
+ <0x660009b0 0x40>;
+
+ pinctrl-names = "default";
+ pinctrl-0 = <&nand_sel &uart3_rx &sdio0_d4>;
+
+ /* Select nand function */
+ nand_sel: nand_sel {
+ function = "nand";
+ groups = "nand_grp";
+ };
+
+ /* Pull up the uart3 rx pin */
+ uart3_rx: uart3_rx {
+ pins = "uart3_sin";
+ bias-pull-up;
+ };
+
+ /* Set the drive strength of sdio d4 pin */
+ sdio0_d4: sdio0_d4 {
+ pins = "sdio0_data4";
+ drive-strength = <8>;
+ };
+ };
+
+List of supported functions and groups in Northstar2:
+
+"nand": "nand_grp"
+
+"nor": "nor_data_grp", "nor_adv_grp", "nor_addr_0_3_grp", "nor_addr_4_5_grp",
+ "nor_addr_6_7_grp", "nor_addr_8_9_grp", "nor_addr_10_11_grp",
+ "nor_addr_12_15_grp"
+
+"gpio": "gpio_0_1_grp", "gpio_2_5_grp", "gpio_6_7_grp", "gpio_8_9_grp",
+ "gpio_10_11_grp", "gpio_12_13_grp", "gpio_14_17_grp", "gpio_18_19_grp",
+ "gpio_20_21_grp", "gpio_22_23_grp", "gpio_24_25_grp", "gpio_26_27_grp",
+ "gpio_28_29_grp", "gpio_30_31_grp"
+
+"pcie": "pcie_ab1_clk_wak_grp", "pcie_a3_clk_wak_grp", "pcie_b3_clk_wak_grp",
+ "pcie_b2_clk_wak_grp", "pcie_a2_clk_wak_grp"
+
+"uart0": "uart0_modem_grp", "uart0_rts_cts_grp", "uart0_in_out_grp"
+
+"uart1": "uart1_ext_clk_grp", "uart1_dcd_dsr_grp", "uart1_ri_dtr_grp",
+ "uart1_rts_cts_grp", "uart1_in_out_grp"
+
+"uart2": "uart2_rts_cts_grp"
+
+"pwm": "pwm_0_grp", "pwm_1_grp", "pwm_2_grp", "pwm_3_grp"
+
+
+List of pins that support pinconf parameters:
+
+"qspi_wp", "qspi_hold", "qspi_cs", "qspi_sck", "uart3_sin", "uart3_sout",
+"qspi_mosi", "qspi_miso", "spi0_fss", "spi0_rxd", "spi0_txd", "spi0_sck",
+"spi1_fss", "spi1_rxd", "spi1_txd", "spi1_sck", "sdio0_data7",
+"sdio0_emmc_rst", "sdio0_led_on", "sdio0_wp", "sdio0_data3", "sdio0_data4",
+"sdio0_data5", "sdio0_data6", "sdio0_cmd", "sdio0_data0", "sdio0_data1",
+"sdio0_data2", "sdio1_led_on", "sdio1_wp", "sdio0_cd_l", "sdio0_clk",
+"sdio1_data5", "sdio1_data6", "sdio1_data7", "sdio1_emmc_rst", "sdio1_data1",
+"sdio1_data2", "sdio1_data3", "sdio1_data4", "sdio1_cd_l", "sdio1_clk",
+"sdio1_cmd", "sdio1_data0", "ext_mdio_0", "ext_mdc_0", "usb3_p1_vbus_ppc",
+"usb3_p1_overcurrent", "usb3_p0_vbus_ppc", "usb3_p0_overcurrent",
+"usb2_presence_indication", "usb2_vbus_present", "usb2_vbus_ppc",
+"usb2_overcurrent", "sata_led1", "sata_led0"
diff --git a/Documentation/devicetree/bindings/pinctrl/microchip,pic32-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/microchip,pic32-pinctrl.txt
new file mode 100644
index 000000000000..4b5efa51bec7
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/microchip,pic32-pinctrl.txt
@@ -0,0 +1,60 @@
+* Microchip PIC32 Pin Controller
+
+Please refer to pinctrl-bindings.txt, ../gpio/gpio.txt, and
+../interrupt-controller/interrupts.txt for generic information regarding
+pin controller, GPIO, and interrupt bindings.
+
+PIC32 'pin configuration node' is a node of a group of pins which can be
+used for a specific device or function. This node represents configuraions of
+pins, optional function, and optional mux related configuration.
+
+Required properties for pin controller node:
+ - compatible: "microchip,pic32mada-pinctrl"
+ - reg: Address range of the pinctrl registers.
+ - clocks: Clock specifier (see clock bindings for details)
+
+Required properties for pin configuration sub-nodes:
+ - pins: List of pins to which the configuration applies.
+
+Optional properties for pin configuration sub-nodes:
+----------------------------------------------------
+ - function: Mux function for the specified pins.
+ - bias-pull-up: Enable weak pull-up.
+ - bias-pull-down: Enable weak pull-down.
+ - input-enable: Set the pin as an input.
+ - output-low: Set the pin as an output level low.
+ - output-high: Set the pin as an output level high.
+ - microchip,digital: Enable digital I/O.
+ - microchip,analog: Enable analog I/O.
+
+Example:
+
+pic32_pinctrl: pinctrl@1f801400{
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "microchip,pic32mzda-pinctrl";
+ reg = <0x1f801400 0x400>;
+ clocks = <&PBCLK1>;
+
+ pinctrl_uart2: pinctrl_uart2 {
+ uart2-tx {
+ pins = "G9";
+ function = "U2TX";
+ microchip,digital;
+ output-low;
+ };
+ uart2-rx {
+ pins = "B0";
+ function = "U2RX";
+ microchip,digital;
+ input-enable;
+ };
+ };
+};
+
+uart2: serial@1f822200 {
+ compatible = "microchip,pic32mzda-uart";
+ reg = <0x1f822200 0x50>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_uart2>;
+};
diff --git a/Documentation/devicetree/bindings/pinctrl/nxp,lpc1850-scu.txt b/Documentation/devicetree/bindings/pinctrl/nxp,lpc1850-scu.txt
index df0309c57505..bd8b0c69fa44 100644
--- a/Documentation/devicetree/bindings/pinctrl/nxp,lpc1850-scu.txt
+++ b/Documentation/devicetree/bindings/pinctrl/nxp,lpc1850-scu.txt
@@ -22,6 +22,10 @@ The following generic nodes are supported:
- input-schmitt-disable
- slew-rate
+NXP specific properties:
+ - nxp,gpio-pin-interrupt : Assign pin to gpio pin interrupt controller
+ irq number 0 to 7. See example below.
+
Not all pins support all properties so either refer to the NXP 1850/4350
user manual or the pin table in the pinctrl-lpc18xx driver for supported
pin properties.
@@ -54,4 +58,14 @@ pinctrl: pinctrl@40086000 {
bias-disable;
};
};
+
+ gpio_joystick_pins: gpio-joystick-pins {
+ gpio_joystick_1_cfg {
+ pins = "p9_0";
+ function = "gpio";
+ nxp,gpio-pin-interrupt = <0>;
+ input-enable;
+ bias-disable;
+ };
+ };
};
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt65xx.txt b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt65xx.txt
index 9ffb0b276bb4..17631d0a9af7 100644
--- a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt65xx.txt
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt65xx.txt
@@ -6,6 +6,7 @@ Required properties:
- compatible: value should be one of the following.
"mediatek,mt2701-pinctrl", compatible with mt2701 pinctrl.
"mediatek,mt6397-pinctrl", compatible with mt6397 pinctrl.
+ "mediatek,mt7623-pinctrl", compatible with mt7623 pinctrl.
"mediatek,mt8127-pinctrl", compatible with mt8127 pinctrl.
"mediatek,mt8135-pinctrl", compatible with mt8135 pinctrl.
"mediatek,mt8173-pinctrl", compatible with mt8173 pinctrl.
diff --git a/Documentation/devicetree/bindings/pinctrl/qcom,ipq4019-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/qcom,ipq4019-pinctrl.txt
new file mode 100644
index 000000000000..cfb8500dd56b
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/qcom,ipq4019-pinctrl.txt
@@ -0,0 +1,74 @@
+Qualcomm Atheros IPQ4019 TLMM block
+
+This is the Top Level Mode Multiplexor block found on the Qualcomm IPQ8019
+platform, it provides pinctrl, pinmux, pinconf, and gpiolib facilities.
+
+Required properties:
+- compatible: "qcom,ipq4019-pinctrl"
+- reg: Should be the base address and length of the TLMM block.
+- interrupts: Should be the parent IRQ of the TLMM block.
+- interrupt-controller: Marks the device node as an interrupt controller.
+- #interrupt-cells: Should be two.
+- gpio-controller: Marks the device node as a GPIO controller.
+- #gpio-cells : Should be two.
+ The first cell is the gpio pin number and the
+ second cell is used for optional parameters.
+
+Please refer to ../gpio/gpio.txt and ../interrupt-controller/interrupts.txt for
+a general description of GPIO and interrupt bindings.
+
+Please refer to pinctrl-bindings.txt in this directory for details of the
+common pinctrl bindings used by client devices, including the meaning of the
+phrase "pin configuration node".
+
+The pin configuration nodes act as a container for an abitrary number of
+subnodes. Each of these subnodes represents some desired configuration for a
+pin, a group, or a list of pins or groups. This configuration can include the
+mux function to select on those pin(s)/group(s), and various pin configuration
+parameters, such as pull-up, drive strength, etc.
+
+The name of each subnode is not important; all subnodes should be enumerated
+and processed purely based on their content.
+
+Each subnode only affects those parameters that are explicitly listed. In
+other words, a subnode that lists a mux function but no pin configuration
+parameters implies no information about any pin configuration parameters.
+Similarly, a pin subnode that describes a pullup parameter implies no
+information about e.g. the mux function.
+
+
+The following generic properties as defined in pinctrl-bindings.txt are valid
+to specify in a pin configuration subnode:
+ pins, function, bias-disable, bias-pull-down, bias-pull,up, drive-strength.
+
+Non-empty subnodes must specify the 'pins' property.
+Note that not all properties are valid for all pins.
+
+
+Valid values for qcom,pins are:
+ gpio0-gpio99
+ Supports mux, bias and drive-strength
+
+Valid values for qcom,function are:
+gpio, blsp_uart1, blsp_i2c0, blsp_i2c1, blsp_uart0, blsp_spi1, blsp_spi0
+
+Example:
+
+ tlmm: pinctrl@1000000 {
+ compatible = "qcom,ipq4019-pinctrl";
+ reg = <0x1000000 0x300000>;
+
+ gpio-controller;
+ #gpio-cells = <2>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ interrupts = <0 208 0>;
+
+ serial_pins: serial_pinmux {
+ mux {
+ pins = "gpio60", "gpio61";
+ function = "blsp_uart0";
+ bias-disable;
+ };
+ };
+ };
diff --git a/Documentation/devicetree/bindings/pinctrl/rockchip,pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/rockchip,pinctrl.txt
index 0cd701b1947f..c68b9554561f 100644
--- a/Documentation/devicetree/bindings/pinctrl/rockchip,pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/rockchip,pinctrl.txt
@@ -22,7 +22,7 @@ Required properties for iomux controller:
- compatible: one of "rockchip,rk2928-pinctrl", "rockchip,rk3066a-pinctrl"
"rockchip,rk3066b-pinctrl", "rockchip,rk3188-pinctrl"
"rockchip,rk3228-pinctrl", "rockchip,rk3288-pinctrl"
- "rockchip,rk3368-pinctrl"
+ "rockchip,rk3368-pinctrl", "rockchip,rk3399-pinctrl"
- rockchip,grf: phandle referencing a syscon providing the
"general register files"
diff --git a/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt
new file mode 100644
index 000000000000..7b4800cc251e
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/st,stm32-pinctrl.txt
@@ -0,0 +1,126 @@
+* STM32 GPIO and Pin Mux/Config controller
+
+STMicroelectronics's STM32 MCUs intregrate a GPIO and Pin mux/config hardware
+controller. It controls the input/output settings on the available pins and
+also provides ability to multiplex and configure the output of various on-chip
+controllers onto these pads.
+
+Pin controller node:
+Required properies:
+ - compatible: value should be one of the following:
+ (a) "st,stm32f429-pinctrl"
+ - #address-cells: The value of this property must be 1
+ - #size-cells : The value of this property must be 1
+ - ranges : defines mapping between pin controller node (parent) to
+ gpio-bank node (children).
+ - pins-are-numbered: Specify the subnodes are using numbered pinmux to
+ specify pins.
+
+GPIO controller/bank node:
+Required properties:
+ - gpio-controller : Indicates this device is a GPIO controller
+ - #gpio-cells : Should be two.
+ The first cell is the pin number
+ The second one is the polarity:
+ - 0 for active high
+ - 1 for active low
+ - reg : The gpio address range, relative to the pinctrl range
+ - clocks : clock that drives this bank
+ - st,bank-name : Should be a name string for this bank as specified in
+ the datasheet
+
+Optional properties:
+ - reset: : Reference to the reset controller
+
+Example:
+#include <dt-bindings/pinctrl/stm32f429-pinfunc.h>
+...
+
+ pin-controller {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ compatible = "st,stm32f429-pinctrl";
+ ranges = <0 0x40020000 0x3000>;
+ pins-are-numbered;
+
+ gpioa: gpio@40020000 {
+ gpio-controller;
+ #gpio-cells = <2>;
+ reg = <0x0 0x400>;
+ resets = <&reset_ahb1 0>;
+ st,bank-name = "GPIOA";
+ };
+ ...
+ pin-functions nodes follow...
+ };
+
+Contents of function subnode node:
+----------------------------------
+Subnode format
+A pinctrl node should contain at least one subnode representing the
+pinctrl group available on the machine. Each subnode will list the
+pins it needs, and how they should be configured, with regard to muxer
+configuration, pullups, drive, output high/low and output speed.
+
+ node {
+ pinmux = <PIN_NUMBER_PINMUX>;
+ GENERIC_PINCONFIG;
+ };
+
+Required properties:
+- pinmux: integer array, represents gpio pin number and mux setting.
+ Supported pin number and mux varies for different SoCs, and are defined in
+ dt-bindings/pinctrl/<soc>-pinfunc.h directly.
+ These defines are calculated as:
+ ((port * 16 + line) << 8) | function
+ With:
+ - port: The gpio port index (PA = 0, PB = 1, ..., PK = 11)
+ - line: The line offset within the port (PA0 = 0, PA1 = 1, ..., PA15 = 15)
+ - function: The function number, can be:
+ * 0 : GPIO
+ * 1 : Alternate Function 0
+ * 2 : Alternate Function 1
+ * 3 : Alternate Function 2
+ * ...
+ * 16 : Alternate Function 15
+ * 17 : Analog
+
+Optional properties:
+- GENERIC_PINCONFIG: is the generic pinconfig options to use.
+ Available options are:
+ - bias-disable,
+ - bias-pull-down,
+ - bias-pull-up,
+ - drive-push-pull,
+ - drive-open-drain,
+ - output-low
+ - output-high
+ - slew-rate = <x>, with x being:
+ < 0 > : Low speed
+ < 1 > : Medium speed
+ < 2 > : Fast speed
+ < 3 > : High speed
+
+Example:
+
+pin-controller {
+...
+ usart1_pins_a: usart1@0 {
+ pins1 {
+ pinmux = <STM32F429_PA9_FUNC_USART1_TX>;
+ bias-disable;
+ drive-push-pull;
+ slew-rate = <0>;
+ };
+ pins2 {
+ pinmux = <STM32F429_PA10_FUNC_USART1_RX>;
+ bias-disable;
+ };
+ };
+};
+
+&usart1 {
+ pinctrl-0 = <&usart1_pins_a>;
+ pinctrl-names = "default";
+ status = "okay";
+};