diff options
Diffstat (limited to 'Documentation/devicetree/bindings/gpio')
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio.txt | 36 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/gpio_atmel.txt | 5 | ||||
| -rw-r--r-- | Documentation/devicetree/bindings/gpio/led.txt | 58 |
3 files changed, 41 insertions, 58 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt index 4e16ba4..a336287 100644 --- a/Documentation/devicetree/bindings/gpio/gpio.txt +++ b/Documentation/devicetree/bindings/gpio/gpio.txt @@ -75,4 +75,40 @@ Example of two SOC GPIO banks defined as gpio-controller nodes: gpio-controller; }; +2.1) gpio-controller and pinctrl subsystem +------------------------------------------ +gpio-controller on a SOC might be tightly coupled with the pinctrl +subsystem, in the sense that the pins can be used by other functions +together with optional gpio feature. + +While the pin allocation is totally managed by the pin ctrl subsystem, +gpio (under gpiolib) is still maintained by gpio drivers. It may happen +that different pin ranges in a SoC is managed by different gpio drivers. + +This makes it logical to let gpio drivers announce their pin ranges to +the pin ctrl subsystem and call 'pinctrl_request_gpio' in order to +request the corresponding pin before any gpio usage. + +For this, the gpio controller can use a pinctrl phandle and pins to +announce the pinrange to the pin ctrl subsystem. For example, + + qe_pio_e: gpio-controller@1460 { + #gpio-cells = <2>; + compatible = "fsl,qe-pario-bank-e", "fsl,qe-pario-bank"; + reg = <0x1460 0x18>; + gpio-controller; + gpio-ranges = <&pinctrl1 20 10>, <&pinctrl2 50 20>; + + } + +where, + &pinctrl1 and &pinctrl2 is the phandle to the pinctrl DT node. + + Next values specify the base pin and number of pins for the range + handled by 'qe_pio_e' gpio. In the given example from base pin 20 to + pin 29 under pinctrl1 and pin 50 to pin 69 under pinctrl2 is handled + by this gpio controller. + +The pinctrl node must have "#gpio-range-cells" property to show number of +arguments to pass with phandle from gpio controllers node. diff --git a/Documentation/devicetree/bindings/gpio/gpio_atmel.txt b/Documentation/devicetree/bindings/gpio/gpio_atmel.txt index 66efc80..85f8c0d 100644 --- a/Documentation/devicetree/bindings/gpio/gpio_atmel.txt +++ b/Documentation/devicetree/bindings/gpio/gpio_atmel.txt @@ -9,6 +9,10 @@ Required properties: unused). - gpio-controller: Marks the device node as a GPIO controller. +optional properties: +- #gpio-lines: Number of gpio if absent 32. + + Example: pioA: gpio@fffff200 { compatible = "atmel,at91rm9200-gpio"; @@ -16,5 +20,6 @@ Example: interrupts = <2 4>; #gpio-cells = <2>; gpio-controller; + #gpio-lines = <19>; }; diff --git a/Documentation/devicetree/bindings/gpio/led.txt b/Documentation/devicetree/bindings/gpio/led.txt deleted file mode 100644 index edc83c1..0000000 --- a/Documentation/devicetree/bindings/gpio/led.txt +++ /dev/null @@ -1,58 +0,0 @@ -LEDs connected to GPIO lines - -Required properties: -- compatible : should be "gpio-leds". - -Each LED is represented as a sub-node of the gpio-leds device. Each -node's name represents the name of the corresponding LED. - -LED sub-node properties: -- gpios : Should specify the LED's GPIO, see "gpios property" in - Documentation/devicetree/bindings/gpio/gpio.txt. Active low LEDs should be - indicated using flags in the GPIO specifier. -- label : (optional) The label for this LED. If omitted, the label is - taken from the node name (excluding the unit address). -- linux,default-trigger : (optional) This parameter, if present, is a - string defining the trigger assigned to the LED. Current triggers are: - "backlight" - LED will act as a back-light, controlled by the framebuffer - system - "default-on" - LED will turn on, but see "default-state" below - "heartbeat" - LED "double" flashes at a load average based rate - "ide-disk" - LED indicates disk activity - "timer" - LED flashes at a fixed, configurable rate -- default-state: (optional) The initial state of the LED. Valid - values are "on", "off", and "keep". If the LED is already on or off - and the default-state property is set the to same value, then no - glitch should be produced where the LED momentarily turns off (or - on). The "keep" setting will keep the LED at whatever its current - state is, without producing a glitch. The default is off if this - property is not present. - -Examples: - -leds { - compatible = "gpio-leds"; - hdd { - label = "IDE Activity"; - gpios = <&mcu_pio 0 1>; /* Active low */ - linux,default-trigger = "ide-disk"; - }; - - fault { - gpios = <&mcu_pio 1 0>; - /* Keep LED on if BIOS detected hardware fault */ - default-state = "keep"; - }; -}; - -run-control { - compatible = "gpio-leds"; - red { - gpios = <&mpc8572 6 0>; - default-state = "off"; - }; - green { - gpios = <&mpc8572 7 0>; - default-state = "on"; - }; -}; |
