| Laxminath Kasam | 7a72141 | 2016-11-02 20:02:00 +0530 | [diff] [blame] | 1 | Qualcomm Technologies, Inc. LPI GPIO controller driver |
| 2 | |
| 3 | This DT bindings describes the GPIO controller driver |
| 4 | being added for supporting LPI (Low Power Island) TLMM |
| 5 | from QTI chipsets. |
| 6 | |
| 7 | Following properties are for LPI GPIO controller device main node. |
| 8 | - compatible: |
| 9 | Usage: required |
| 10 | Value type: <string> |
| 11 | Definition: must be "qcom,lpi-pinctrl" |
| 12 | |
| 13 | - reg: |
| 14 | Usage: required |
| 15 | Value type: <prop-encoded-array> |
| 16 | Definition: Register base of the GPIO controller and length. |
| 17 | |
| 18 | - qcom,num-gpios: |
| 19 | Usage: required |
| 20 | Value type: <u32> |
| 21 | Definition: Number of GPIOs supported by the controller. |
| 22 | |
| 23 | - gpio-controller: |
| 24 | Usage: required |
| 25 | Value type: <none> |
| 26 | Definition: Used to mark the device node as a GPIO controller. |
| 27 | |
| 28 | - #gpio-cells: |
| 29 | Usage: required |
| 30 | Value type: <u32> |
| 31 | Definition: Must be 2; |
| 32 | The first cell will be used to define gpio number and the |
| 33 | second denotes the flags for this gpio. |
| 34 | |
| 35 | Please refer to ../gpio/gpio.txt for general description of GPIO bindings. |
| 36 | |
| 37 | Please refer to pinctrl-bindings.txt in this directory for details of the |
| 38 | common pinctrl bindings used by client devices, including the meaning of the |
| 39 | phrase "pin configuration node". |
| 40 | |
| 41 | The pin configuration nodes act as a container for an arbitrary number of |
| 42 | subnodes. Each of these subnodes represents some desired configuration for a |
| 43 | pin or a list of pins. This configuration can include the |
| 44 | mux function to select on those pin(s), and various pin configuration |
| 45 | parameters, as listed below. |
| 46 | |
| 47 | SUBNODES: |
| 48 | |
| 49 | The name of each subnode is not important; all subnodes should be enumerated |
| 50 | and processed purely based on their content. |
| 51 | |
| 52 | Each subnode only affects those parameters that are explicitly listed. In |
| 53 | other words, a subnode that lists a mux function but no pin configuration |
| 54 | parameters implies no information about any pin configuration parameters. |
| 55 | Similarly, a pin subnode that describes a pullup parameter implies no |
| 56 | information about e.g. the mux function. |
| 57 | |
| 58 | The following generic properties as defined in pinctrl-bindings.txt are valid |
| 59 | to specify in a pin configuration subnode: |
| 60 | |
| 61 | - pins: |
| 62 | Usage: required |
| 63 | Value type: <string-array> |
| 64 | Definition: List of gpio pins affected by the properties specified in |
| 65 | this subnode. Valid pins are: gpio0-gpio31 for LPI. |
| 66 | |
| 67 | - function: |
| 68 | Usage: required |
| 69 | Value type: <string> |
| 70 | Definition: Specify the alternative function to be configured for the |
| 71 | specified pins. Valid values are: |
| 72 | "gpio", |
| 73 | "func1", |
| 74 | "func2", |
| 75 | "func3", |
| 76 | "func4", |
| 77 | "func5" |
| 78 | |
| 79 | - bias-disable: |
| 80 | Usage: optional |
| 81 | Value type: <none> |
| 82 | Definition: The specified pins should be configured as no pull. |
| 83 | |
| 84 | - bias-pull-down: |
| 85 | Usage: optional |
| 86 | Value type: <none> |
| 87 | Definition: The specified pins should be configured as pull down. |
| 88 | |
| 89 | - bias-bus-hold: |
| 90 | Usage: optional |
| 91 | Value type: <none> |
| 92 | Definition: The specified pins should be configured as bus-keeper mode. |
| 93 | |
| 94 | - bias-pull-up: |
| 95 | Usage: optional |
| 96 | Value type: <empty> |
| 97 | Definition: The specified pins should be configured as pull up. |
| 98 | |
| 99 | - input-enable: |
| 100 | Usage: optional |
| 101 | Value type: <none> |
| 102 | Definition: The specified pins are put in input mode. |
| 103 | |
| 104 | - output-high: |
| 105 | Usage: optional |
| 106 | Value type: <none> |
| 107 | Definition: The specified pins are configured in output mode, driven |
| 108 | high. |
| 109 | |
| 110 | - output-low: |
| 111 | Usage: optional |
| 112 | Value type: <none> |
| 113 | Definition: The specified pins are configured in output mode, driven |
| 114 | low. |
| 115 | |
| 116 | - qcom,drive-strength: |
| 117 | Usage: optional |
| 118 | Value type: <u32> |
| 119 | Definition: Selects the drive strength for the specified pins. |
| 120 | |
| 121 | Example: |
| 122 | |
| 123 | lpi_tlmm: lpi_pinctrl@152c000 { |
| 124 | compatible = "qcom,lpi-pinctrl"; |
| 125 | qcom,num-gpios = <32>; |
| 126 | reg = <0x152c000 0>; |
| 127 | gpio-controller; |
| 128 | #gpio-cells = <2>; |
| 129 | |
| 130 | hph_comp_active: hph_comp_active { |
| 131 | mux { |
| 132 | pins = "gpio22"; |
| 133 | function = "func1"; |
| 134 | }; |
| 135 | |
| 136 | config { |
| 137 | pins = "gpio22"; |
| 138 | output-high; |
| 139 | qcom,drive-strength = <8>; |
| 140 | }; |
| 141 | }; |
| 142 | |
| 143 | hph_comp_sleep: hph_comp_sleep { |
| 144 | mux { |
| 145 | pins = "gpio22"; |
| 146 | function = "func1"; |
| 147 | }; |
| 148 | |
| 149 | config { |
| 150 | pins = "gpio22"; |
| 151 | qcom,drive-strength = <2>; |
| 152 | }; |
| 153 | }; |
| 154 | }; |