|  | Samsung GPIO and Pin Mux/Config controller | 
|  |  | 
|  | Samsung's ARM based SoC's integrates a GPIO and Pin mux/config hardware | 
|  | controller. It controls the input/output settings on the available pads/pins | 
|  | and also provides ability to multiplex and configure the output of various | 
|  | on-chip controllers onto these pads. | 
|  |  | 
|  | Required Properties: | 
|  | - compatible: should be one of the following. | 
|  | - "samsung,s3c2412-pinctrl": for S3C2412-compatible pin-controller, | 
|  | - "samsung,s3c2416-pinctrl": for S3C2416-compatible pin-controller, | 
|  | - "samsung,s3c2440-pinctrl": for S3C2440-compatible pin-controller, | 
|  | - "samsung,s3c2450-pinctrl": for S3C2450-compatible pin-controller, | 
|  | - "samsung,s3c64xx-pinctrl": for S3C64xx-compatible pin-controller, | 
|  | - "samsung,s5pv210-pinctrl": for S5PV210-compatible pin-controller, | 
|  | - "samsung,exynos4210-pinctrl": for Exynos4210 compatible pin-controller. | 
|  | - "samsung,exynos4x12-pinctrl": for Exynos4x12 compatible pin-controller. | 
|  | - "samsung,exynos5250-pinctrl": for Exynos5250 compatible pin-controller. | 
|  | - "samsung,exynos5260-pinctrl": for Exynos5260 compatible pin-controller. | 
|  | - "samsung,exynos5420-pinctrl": for Exynos5420 compatible pin-controller. | 
|  | - "samsung,exynos7-pinctrl": for Exynos7 compatible pin-controller. | 
|  |  | 
|  | - reg: Base address of the pin controller hardware module and length of | 
|  | the address space it occupies. | 
|  |  | 
|  | - Pin banks as child nodes: Pin banks of the controller are represented by child | 
|  | nodes of the controller node. Bank name is taken from name of the node. Each | 
|  | bank node must contain following properties: | 
|  |  | 
|  | - gpio-controller: identifies the node as a gpio controller and pin bank. | 
|  | - #gpio-cells: 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. | 
|  |  | 
|  | Eg: <&gpx2 6 0> | 
|  | <[phandle of the gpio controller node] | 
|  | [pin number within the gpio controller] | 
|  | [flags]> | 
|  |  | 
|  | Values for gpio specifier: | 
|  | - Pin number: is a value between 0 to 7. | 
|  | - Flags: 0 - Active High | 
|  | 1 - Active Low | 
|  |  | 
|  | - Pin mux/config groups as child nodes: The pin mux (selecting pin function | 
|  | mode) and pin config (pull up/down, driver strength) settings are represented | 
|  | as child nodes of the pin-controller node. There should be atleast one | 
|  | child node and there is no limit on the count of these child nodes. It is | 
|  | also possible for a child node to consist of several further child nodes | 
|  | to allow grouping multiple pinctrl groups into one. The format of second | 
|  | level child nodes is exactly the same as for first level ones and is | 
|  | described below. | 
|  |  | 
|  | The child node should contain a list of pin(s) on which a particular pin | 
|  | function selection or pin configuration (or both) have to applied. This | 
|  | list of pins is specified using the property name "samsung,pins". There | 
|  | should be atleast one pin specfied for this property and there is no upper | 
|  | limit on the count of pins that can be specified. The pins are specified | 
|  | using pin names which are derived from the hardware manual of the SoC. As | 
|  | an example, the pins in GPA0 bank of the pin controller can be represented | 
|  | as "gpa0-0", "gpa0-1", "gpa0-2" and so on. The names should be in lower case. | 
|  | The format of the pin names should be (as per the hardware manual) | 
|  | "[pin bank name]-[pin number within the bank]". | 
|  |  | 
|  | The pin function selection that should be applied on the pins listed in the | 
|  | child node is specified using the "samsung,pin-function" property. The value | 
|  | of this property that should be applied to each of the pins listed in the | 
|  | "samsung,pins" property should be picked from the hardware manual of the SoC | 
|  | for the specified pin group. This property is optional in the child node if | 
|  | no specific function selection is desired for the pins listed in the child | 
|  | node. The value of this property is used as-is to program the pin-controller | 
|  | function selector register of the pin-bank. | 
|  |  | 
|  | The child node can also optionally specify one or more of the pin | 
|  | configuration that should be applied on all the pins listed in the | 
|  | "samsung,pins" property of the child node. The following pin configuration | 
|  | properties are supported. | 
|  |  | 
|  | - samsung,pin-val: Initial value of pin output buffer. | 
|  | - samsung,pin-pud: Pull up/down configuration. | 
|  | - samsung,pin-drv: Drive strength configuration. | 
|  | - samsung,pin-pud-pdn: Pull up/down configuration in power down mode. | 
|  | - samsung,pin-drv-pdn: Drive strength configuration in power down mode. | 
|  |  | 
|  | The values specified by these config properties should be derived from the | 
|  | hardware manual and these values are programmed as-is into the pin | 
|  | pull up/down and driver strength register of the pin-controller. | 
|  |  | 
|  | Note: A child should include atleast a pin function selection property or | 
|  | pin configuration property (one or more) or both. | 
|  |  | 
|  | The client nodes that require a particular pin function selection and/or | 
|  | pin configuration should use the bindings listed in the "pinctrl-bindings.txt" | 
|  | file. | 
|  |  | 
|  | External GPIO and Wakeup Interrupts: | 
|  |  | 
|  | The controller supports two types of external interrupts over gpio. The first | 
|  | is the external gpio interrupt and second is the external wakeup interrupts. | 
|  | The difference between the two is that the external wakeup interrupts can be | 
|  | used as system wakeup events. | 
|  |  | 
|  | A. External GPIO Interrupts: For supporting external gpio interrupts, the | 
|  | following properties should be specified in the pin-controller device node. | 
|  |  | 
|  | - interrupt-parent: phandle of the interrupt parent to which the external | 
|  | GPIO interrupts are forwarded to. | 
|  | - interrupts: interrupt specifier for the controller. The format and value of | 
|  | the interrupt specifier depends on the interrupt parent for the controller. | 
|  |  | 
|  | In addition, following properties must be present in node of every bank | 
|  | of pins supporting GPIO interrupts: | 
|  |  | 
|  | - interrupt-controller: identifies the controller node as interrupt-parent. | 
|  | - #interrupt-cells: the value of this property should be 2. | 
|  | - First Cell: represents the external gpio interrupt number local to the | 
|  | external gpio interrupt space of the controller. | 
|  | - Second Cell: flags to identify the type of the interrupt | 
|  | - 1 = rising edge triggered | 
|  | - 2 = falling edge triggered | 
|  | - 3 = rising and falling edge triggered | 
|  | - 4 = high level triggered | 
|  | - 8 = low level triggered | 
|  |  | 
|  | B. External Wakeup Interrupts: For supporting external wakeup interrupts, a | 
|  | child node representing the external wakeup interrupt controller should be | 
|  | included in the pin-controller device node. This child node should include | 
|  | the following properties. | 
|  |  | 
|  | - compatible: identifies the type of the external wakeup interrupt controller | 
|  | The possible values are: | 
|  | - samsung,s3c2410-wakeup-eint: represents wakeup interrupt controller | 
|  | found on Samsung S3C24xx SoCs except S3C2412 and S3C2413, | 
|  | - samsung,s3c2412-wakeup-eint: represents wakeup interrupt controller | 
|  | found on Samsung S3C2412 and S3C2413 SoCs, | 
|  | - samsung,s3c64xx-wakeup-eint: represents wakeup interrupt controller | 
|  | found on Samsung S3C64xx SoCs, | 
|  | - samsung,exynos4210-wakeup-eint: represents wakeup interrupt controller | 
|  | found on Samsung Exynos4210 and S5PC110/S5PV210 SoCs. | 
|  | - samsung,exynos7-wakeup-eint: represents wakeup interrupt controller | 
|  | found on Samsung Exynos7 SoC. | 
|  | - interrupt-parent: phandle of the interrupt parent to which the external | 
|  | wakeup interrupts are forwarded to. | 
|  | - interrupts: interrupt used by multiplexed wakeup interrupts. | 
|  |  | 
|  | In addition, following properties must be present in node of every bank | 
|  | of pins supporting wake-up interrupts: | 
|  |  | 
|  | - interrupt-controller: identifies the node as interrupt-parent. | 
|  | - #interrupt-cells: the value of this property should be 2 | 
|  | - First Cell: represents the external wakeup interrupt number local to | 
|  | the external wakeup interrupt space of the controller. | 
|  | - Second Cell: flags to identify the type of the interrupt | 
|  | - 1 = rising edge triggered | 
|  | - 2 = falling edge triggered | 
|  | - 3 = rising and falling edge triggered | 
|  | - 4 = high level triggered | 
|  | - 8 = low level triggered | 
|  |  | 
|  | Node of every bank of pins supporting direct wake-up interrupts (without | 
|  | multiplexing) must contain following properties: | 
|  |  | 
|  | - interrupt-parent: phandle of the interrupt parent to which the external | 
|  | wakeup interrupts are forwarded to. | 
|  | - interrupts: interrupts of the interrupt parent which are used for external | 
|  | wakeup interrupts from pins of the bank, must contain interrupts for all | 
|  | pins of the bank. | 
|  |  | 
|  | Aliases: | 
|  |  | 
|  | All the pin controller nodes should be represented in the aliases node using | 
|  | the following format 'pinctrl{n}' where n is a unique number for the alias. | 
|  |  | 
|  | Aliases for controllers compatible with "samsung,exynos7-pinctrl": | 
|  | - pinctrl0: pin controller of ALIVE block, | 
|  | - pinctrl1: pin controller of BUS0 block, | 
|  | - pinctrl2: pin controller of NFC block, | 
|  | - pinctrl3: pin controller of TOUCH block, | 
|  | - pinctrl4: pin controller of FF block, | 
|  | - pinctrl5: pin controller of ESE block, | 
|  | - pinctrl6: pin controller of FSYS0 block, | 
|  | - pinctrl7: pin controller of FSYS1 block, | 
|  | - pinctrl8: pin controller of BUS1 block, | 
|  | - pinctrl9: pin controller of AUDIO block, | 
|  |  | 
|  | Example: A pin-controller node with pin banks: | 
|  |  | 
|  | pinctrl_0: pinctrl@11400000 { | 
|  | compatible = "samsung,exynos4210-pinctrl"; | 
|  | reg = <0x11400000 0x1000>; | 
|  | interrupts = <0 47 0>; | 
|  |  | 
|  | /* ... */ | 
|  |  | 
|  | /* Pin bank without external interrupts */ | 
|  | gpy0: gpy0 { | 
|  | gpio-controller; | 
|  | #gpio-cells = <2>; | 
|  | }; | 
|  |  | 
|  | /* ... */ | 
|  |  | 
|  | /* Pin bank with external GPIO or muxed wake-up interrupts */ | 
|  | gpj0: gpj0 { | 
|  | gpio-controller; | 
|  | #gpio-cells = <2>; | 
|  |  | 
|  | interrupt-controller; | 
|  | #interrupt-cells = <2>; | 
|  | }; | 
|  |  | 
|  | /* ... */ | 
|  |  | 
|  | /* Pin bank with external direct wake-up interrupts */ | 
|  | gpx0: gpx0 { | 
|  | gpio-controller; | 
|  | #gpio-cells = <2>; | 
|  |  | 
|  | interrupt-controller; | 
|  | interrupt-parent = <&gic>; | 
|  | interrupts = <0 16 0>, <0 17 0>, <0 18 0>, <0 19 0>, | 
|  | <0 20 0>, <0 21 0>, <0 22 0>, <0 23 0>; | 
|  | #interrupt-cells = <2>; | 
|  | }; | 
|  |  | 
|  | /* ... */ | 
|  | }; | 
|  |  | 
|  | Example 1: A pin-controller node with pin groups. | 
|  |  | 
|  | pinctrl_0: pinctrl@11400000 { | 
|  | compatible = "samsung,exynos4210-pinctrl"; | 
|  | reg = <0x11400000 0x1000>; | 
|  | interrupts = <0 47 0>; | 
|  |  | 
|  | /* ... */ | 
|  |  | 
|  | uart0_data: uart0-data { | 
|  | samsung,pins = "gpa0-0", "gpa0-1"; | 
|  | samsung,pin-function = <2>; | 
|  | samsung,pin-pud = <0>; | 
|  | samsung,pin-drv = <0>; | 
|  | }; | 
|  |  | 
|  | uart0_fctl: uart0-fctl { | 
|  | samsung,pins = "gpa0-2", "gpa0-3"; | 
|  | samsung,pin-function = <2>; | 
|  | samsung,pin-pud = <0>; | 
|  | samsung,pin-drv = <0>; | 
|  | }; | 
|  |  | 
|  | uart1_data: uart1-data { | 
|  | samsung,pins = "gpa0-4", "gpa0-5"; | 
|  | samsung,pin-function = <2>; | 
|  | samsung,pin-pud = <0>; | 
|  | samsung,pin-drv = <0>; | 
|  | }; | 
|  |  | 
|  | uart1_fctl: uart1-fctl { | 
|  | samsung,pins = "gpa0-6", "gpa0-7"; | 
|  | samsung,pin-function = <2>; | 
|  | samsung,pin-pud = <0>; | 
|  | samsung,pin-drv = <0>; | 
|  | }; | 
|  |  | 
|  | i2c2_bus: i2c2-bus { | 
|  | samsung,pins = "gpa0-6", "gpa0-7"; | 
|  | samsung,pin-function = <3>; | 
|  | samsung,pin-pud = <3>; | 
|  | samsung,pin-drv = <0>; | 
|  | }; | 
|  |  | 
|  | sd4_bus8: sd4-bus-width8 { | 
|  | part-1 { | 
|  | samsung,pins = "gpk0-3", "gpk0-4", | 
|  | "gpk0-5", "gpk0-6"; | 
|  | samsung,pin-function = <3>; | 
|  | samsung,pin-pud = <3>; | 
|  | samsung,pin-drv = <3>; | 
|  | }; | 
|  | part-2 { | 
|  | samsung,pins = "gpk1-3", "gpk1-4", | 
|  | "gpk1-5", "gpk1-6"; | 
|  | samsung,pin-function = <4>; | 
|  | samsung,pin-pud = <4>; | 
|  | samsung,pin-drv = <3>; | 
|  | }; | 
|  | }; | 
|  | }; | 
|  |  | 
|  | Example 2: A pin-controller node with external wakeup interrupt controller node. | 
|  |  | 
|  | pinctrl_1: pinctrl@11000000 { | 
|  | compatible = "samsung,exynos4210-pinctrl"; | 
|  | reg = <0x11000000 0x1000>; | 
|  | interrupts = <0 46 0> | 
|  |  | 
|  | /* ... */ | 
|  |  | 
|  | wakeup-interrupt-controller { | 
|  | compatible = "samsung,exynos4210-wakeup-eint"; | 
|  | interrupt-parent = <&gic>; | 
|  | interrupts = <0 32 0>; | 
|  | }; | 
|  | }; | 
|  |  | 
|  | Example 3: A uart client node that supports 'default' and 'flow-control' states. | 
|  |  | 
|  | uart@13800000 { | 
|  | compatible = "samsung,exynos4210-uart"; | 
|  | reg = <0x13800000 0x100>; | 
|  | interrupts = <0 52 0>; | 
|  | pinctrl-names = "default", "flow-control; | 
|  | pinctrl-0 = <&uart0_data>; | 
|  | pinctrl-1 = <&uart0_data &uart0_fctl>; | 
|  | }; | 
|  |  | 
|  | Example 4: Set up the default pin state for uart controller. | 
|  |  | 
|  | static int s3c24xx_serial_probe(struct platform_device *pdev) { | 
|  | struct pinctrl *pinctrl; | 
|  |  | 
|  | /* ... */ | 
|  |  | 
|  | pinctrl = devm_pinctrl_get_select_default(&pdev->dev); | 
|  | } | 
|  |  | 
|  | Example 5: A display port client node that supports 'default' pinctrl state | 
|  | and gpio binding. | 
|  |  | 
|  | display-port-controller { | 
|  | /* ... */ | 
|  |  | 
|  | samsung,hpd-gpio = <&gpx2 6 0>; | 
|  | pinctrl-names = "default"; | 
|  | pinctrl-0 = <&dp_hpd>; | 
|  | }; | 
|  |  | 
|  | Example 6: Request the gpio for display port controller | 
|  |  | 
|  | static int exynos_dp_probe(struct platform_device *pdev) | 
|  | { | 
|  | int hpd_gpio, ret; | 
|  | struct device *dev = &pdev->dev; | 
|  | struct device_node *dp_node = dev->of_node; | 
|  |  | 
|  | /* ... */ | 
|  |  | 
|  | hpd_gpio = of_get_named_gpio(dp_node, "samsung,hpd-gpio", 0); | 
|  |  | 
|  | /* ... */ | 
|  |  | 
|  | ret = devm_gpio_request_one(&pdev->dev, hpd_gpio, GPIOF_IN, | 
|  | "hpd_gpio"); | 
|  | /* ... */ | 
|  | } |