[PATCH 2/3] dt-bindings: pinctrl: mt8192: add binding document
Zhiyong Tao
zhiyong.tao at mediatek.com
Fri Jul 10 03:27:16 EDT 2020
The commit adds mt8192 compatible node in binding document.
Signed-off-by: Zhiyong Tao <zhiyong.tao at mediatek.com>
---
.../bindings/pinctrl/pinctrl-mt8192.yaml | 170 ++++++++++++++++++
1 file changed, 170 insertions(+)
create mode 100644 Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
diff --git a/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
new file mode 100644
index 000000000000..c698b7f65950
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/pinctrl-mt8192.yaml
@@ -0,0 +1,170 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pinctrl/pinctrl-mt8192.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Mediatek MT8192 Pin Controller
+
+maintainers:
+ - Linus Walleij <linus.walleij at linaro.org>
+
+description: |
+ The Mediatek's Pin controller is used to control SoC pins.
+
+properties:
+ compatible:
+ const: mediatek,mt8192-pinctrl
+
+ gpio-controller: true
+
+ '#gpio-cells':
+ description:
+ Number of cells in GPIO specifier. Since the generic GPIO binding is used,
+ the amount of cells must be specified as 2. See the below
+ mentioned gpio binding representation for description of particular cells.
+ const: 2
+
+ gpio-ranges:
+ description: gpio valid number range.
+ maxItems: 1
+
+ reg:
+ description:
+ Physical address base for gpio base registers. There are 11 GPIO
+ physical address base in mt8192.
+ maxItems: 11
+
+ reg-names:
+ description:
+ Gpio base register names. There are 11 gpio base register names in mt8192.
+ They are "iocfg0", "iocfg_rm", "iocfg_bm", "iocfg_bl", "iocfg_br",
+ "iocfg_lm", "iocfg_lb", "iocfg_rt", "iocfg_lt", "iocfg_tl", "eint".
+ maxItems: 11
+
+ interrupt-controller: true
+
+ '#interrupt-cells':
+ const: 2
+
+ interrupts:
+ description: The interrupt outputs to sysirq.
+ maxItems: 1
+
+#PIN CONFIGURATION NODES
+patternProperties:
+ subnode format:
+ description:
+ A pinctrl node should contain at least one subnodes representing the
+ pinctrl groups 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 strength, input enable/disable and
+ input schmitt.
+
+ node {
+ pinmux = <PIN_NUMBER_PINMUX>;
+ GENERIC_PINCONFIG;
+ };
+ '-pinmux$':
+ description:
+ Integer array, represents gpio pin number and mux setting.
+ Supported pin number and mux varies for different SoCs, and are defined
+ as macros in dt-bindings/pinctrl/<soc>-pinfunc.h directly.
+ $ref: "/schemas/pinctrl/pincfg-node.yaml"
+
+ GENERIC_PINCONFIG:
+ description:
+ It is the generic pinconfig options to use, bias-disable,
+ bias-pull-down, bias-pull-up, input-enable, input-disable, output-low,
+ output-high, input-schmitt-enable, input-schmitt-disable
+ and drive-strength are valid.
+
+ Some special pins have extra pull up strength, there are R0 and R1 pull-up
+ resistors available, but for user, it's only need to set R1R0 as 00, 01,
+ 10 or 11. So It needs config "mediatek,pull-up-adv" or
+ "mediatek,pull-down-adv" to support arguments for those special pins.
+ Valid arguments are from 0 to 3.
+
+ We can use "mediatek,tdsel" which is an integer describing the steps for
+ output level shifter duty cycle when asserted (high pulse width adjustment).
+ Valid arguments are from 0 to 15.
+ We can use "mediatek,rdsel" which is an integer describing the steps for
+ input level shifter duty cycle when asserted (high pulse width adjustment).
+ Valid arguments are from 0 to 63.
+
+ When config drive-strength, it can support some arguments, such as
+ MTK_DRIVE_4mA, MTK_DRIVE_6mA, etc. See dt-bindings/pinctrl/mt65xx.h.
+ It can only support 2/4/6/8/10/12/14/16mA in mt8192.
+ For I2C pins, there are existing generic driving setup and the specific
+ driving setup. I2C pins can only support 2/4/6/8/10/12/14/16mA driving
+ adjustment in generic driving setup. But in specific driving setup,
+ they can support 0.125/0.25/0.5/1mA adjustment. If we enable specific
+ driving setup for I2C pins, the existing generic driving setup will be
+ disabled. For some special features, we need the I2C pins specific
+ driving setup. The specific driving setup is controlled by E1E0EN.
+ So we need add extra vendor driving preperty instead of
+ the generic driving property.
+ We can add "mediatek,drive-strength-adv = <XXX>;" to describe the specific
+ driving setup property. "XXX" means the value of E1E0EN. EN is 0 or 1.
+ It is used to enable or disable the specific driving setup.
+ E1E0 is used to describe the detail strength specification of the I2C pin.
+ When E1=0/E0=0, the strength is 0.125mA.
+ When E1=0/E0=1, the strength is 0.25mA.
+ When E1=1/E0=0, the strength is 0.5mA.
+ When E1=1/E0=1, the strength is 1mA.
+ So the valid arguments of "mediatek,drive-strength-adv" are from 0 to 7.
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - interrupt-controller
+ - '#interrupt-cells'
+ - gpio-controller
+ - '#gpio-cells'
+ - gpio-ranges
+
+examples:
+ - |
+ #include <dt-bindings/pinctrl/mt8192-pinfunc.h>
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ pio: pinctrl at 10005000 {
+ compatible = "mediatek,mt8192-pinctrl";
+ reg = <0 0x10005000 0 0x1000>,
+ <0 0x11c20000 0 0x1000>,
+ <0 0x11d10000 0 0x1000>,
+ <0 0x11d30000 0 0x1000>,
+ <0 0x11d40000 0 0x1000>,
+ <0 0x11e20000 0 0x1000>,
+ <0 0x11e70000 0 0x1000>,
+ <0 0x11ea0000 0 0x1000>,
+ <0 0x11f20000 0 0x1000>,
+ <0 0x11f30000 0 0x1000>,
+ <0 0x1000b000 0 0x1000>;
+ reg-names = "iocfg0", "iocfg_rm", "iocfg_bm",
+ "iocfg_bl", "iocfg_br", "iocfg_lm",
+ "iocfg_lb", "iocfg_rt", "iocfg_lt",
+ "iocfg_tl", "eint";
+ gpio-controller;
+ #gpio-cells = <2>;
+ gpio-ranges = <&pio 0 0 220>;
+ interrupt-controller;
+ interrupts = <GIC_SPI 212 IRQ_TYPE_LEVEL_HIGH 0>;
+ #interrupt-cells = <2>;
+ i2c0_pins_a: i2c0 {
+ pins {
+ pinmux = <PINMUX_GPIO118__FUNC_SCL1>,
+ <PINMUX_GPIO119__FUNC_SDA1>;
+ mediatek,pull-up-adv = <3>;
+ mediatek,drive-strength-adv = <7>;
+ };
+ };
+ i2c1_pins_a: i2c1 {
+ pins {
+ pinmux = <PINMUX_GPIO141__FUNC_SCL2>,
+ <PINMUX_GPIO142__FUNC_SDA2>;
+ mediatek,pull-down-adv = <2>;
+ mediatek,drive-strength-adv = <4>;
+ };
+ };
+ };
--
2.18.0
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