diff options
Diffstat (limited to 'Documentation/devicetree/bindings/gpio')
6 files changed, 77 insertions, 30 deletions
diff --git a/Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt b/Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt index 805ddcd..120bc49 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-mpc8xxx.txt @@ -1,9 +1,9 @@ -* Freescale MPC512x/MPC8xxx GPIO controller +* Freescale MPC512x/MPC8xxx/Layerscape GPIO controller Required properties: - compatible : Should be "fsl,<soc>-gpio" The following <soc>s are known to be supported: - mpc5121, mpc5125, mpc8349, mpc8572, mpc8610, pq3, qoriq + mpc5121, mpc5125, mpc8349, mpc8572, mpc8610, pq3, qoriq. - reg : Address and length of the register set for the device - interrupts : Should be the port interrupt shared by all 32 pins. - #gpio-cells : Should be two. The first cell is the pin number and @@ -11,6 +11,10 @@ Required properties: 0 = active high 1 = active low +Optional properties: +- little-endian : GPIO registers are used as little endian. If not + present registers are used as big endian by default. + Example: gpio0: gpio@1100 { diff --git a/Documentation/devicetree/bindings/gpio/gpio-msm.txt b/Documentation/devicetree/bindings/gpio/gpio-msm.txt deleted file mode 100644 index ac20e68..0000000 --- a/Documentation/devicetree/bindings/gpio/gpio-msm.txt +++ /dev/null @@ -1,26 +0,0 @@ -MSM GPIO controller bindings - -Required properties: -- compatible: - - "qcom,msm-gpio" for MSM controllers -- #gpio-cells : Should be two. - - first cell is the pin number - - second cell is used to specify optional parameters (unused) -- gpio-controller : Marks the device node as a GPIO controller. -- #interrupt-cells : Should be 2. -- interrupt-controller: Mark the device node as an interrupt controller -- interrupts : Specify the TLMM summary interrupt number -- ngpio : Specify the number of MSM GPIOs - -Example: - - msmgpio: gpio@fd510000 { - compatible = "qcom,msm-gpio"; - gpio-controller; - #gpio-cells = <2>; - interrupt-controller; - #interrupt-cells = <2>; - reg = <0xfd510000 0x4000>; - interrupts = <0 208 0>; - ngpio = <150>; - }; diff --git a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt index b9a42f2..13df993 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-pca953x.txt @@ -24,6 +24,7 @@ Required properties: ti,tca6408 ti,tca6416 ti,tca6424 + ti,tca9539 exar,xra1202 Example: diff --git a/Documentation/devicetree/bindings/gpio/gpio-zynq.txt b/Documentation/devicetree/bindings/gpio/gpio-zynq.txt index db4c6a6..7b54265 100644 --- a/Documentation/devicetree/bindings/gpio/gpio-zynq.txt +++ b/Documentation/devicetree/bindings/gpio/gpio-zynq.txt @@ -12,6 +12,13 @@ Required properties: - interrupts : Interrupt specifier (see interrupt bindings for details) - interrupt-parent : Must be core interrupt controller +- interrupt-controller : Marks the device node as an interrupt controller. +- #interrupt-cells : Should be 2. The first cell is the GPIO number. + The second cell bits[3:0] is used to specify trigger type and level flags: + 1 = low-to-high edge triggered. + 2 = high-to-low edge triggered. + 4 = active high level-sensitive. + 8 = active low level-sensitive. - reg : Address and length of the register set for the device Example: @@ -22,5 +29,7 @@ Example: gpio-controller; interrupt-parent = <&intc>; interrupts = <0 20 4>; + interrupt-controller; + #interrupt-cells = <2>; reg = <0xe000a000 0x1000>; }; diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt index 82d40e2..069cdf6 100644 --- a/Documentation/devicetree/bindings/gpio/gpio.txt +++ b/Documentation/devicetree/bindings/gpio/gpio.txt @@ -54,9 +54,13 @@ only uses one. gpio-specifier may encode: bank, pin position inside the bank, whether pin is open-drain and whether pin is logically inverted. + Exact meaning of each specifier cell is controller specific, and must -be documented in the device tree binding for the device. Use the macros -defined in include/dt-bindings/gpio/gpio.h whenever possible: +be documented in the device tree binding for the device. + +Most controllers are however specifying a generic flag bitfield +in the last cell, so for these, use the macros defined in +include/dt-bindings/gpio/gpio.h whenever possible: Example of a node using GPIOs: @@ -67,6 +71,15 @@ Example of a node using GPIOs: GPIO_ACTIVE_HIGH is 0, so in this example gpio-specifier is "18 0" and encodes GPIO pin number, and GPIO flags as accepted by the "qe_pio_e" gpio-controller. +Optional standard bitfield specifiers for the last cell: + +- Bit 0: 0 means active high, 1 means active low +- Bit 1: 1 means single-ended wiring, see: + https://en.wikipedia.org/wiki/Single-ended_triode + When used with active-low, this means open drain/collector, see: + https://en.wikipedia.org/wiki/Open_collector + When used with active-high, this means open source/emitter + 1.1) GPIO specifier best practices ---------------------------------- @@ -118,6 +131,30 @@ Every GPIO controller node must contain both an empty "gpio-controller" property, and a #gpio-cells integer property, which indicates the number of cells in a gpio-specifier. +Optionally, a GPIO controller may have a "ngpios" property. This property +indicates the number of in-use slots of available slots for GPIOs. The +typical example is something like this: the hardware register is 32 bits +wide, but only 18 of the bits have a physical counterpart. The driver is +generally written so that all 32 bits can be used, but the IP block is reused +in a lot of designs, some using all 32 bits, some using 18 and some using +12. In this case, setting "ngpios = <18>;" informs the driver that only the +first 18 GPIOs, at local offset 0 .. 17, are in use. + +If these GPIOs do not happen to be the first N GPIOs at offset 0...N-1, an +additional bitmask is needed to specify which GPIOs are actually in use, +and which are dummies. The bindings for this case has not yet been +specified, but should be specified if/when such hardware appears. + +Example: + +gpio-controller@00000000 { + compatible = "foo"; + reg = <0x00000000 0x1000>; + gpio-controller; + #gpio-cells = <2>; + ngpios = <18>; +} + The GPIO chip may contain GPIO hog definitions. GPIO hogging is a mechanism providing automatic GPIO request and configuration as part of the gpio-controller's driver probe function. diff --git a/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt b/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt new file mode 100644 index 0000000..50ec2e6 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/netxbig-gpio-ext.txt @@ -0,0 +1,22 @@ +Binding for the GPIO extension bus found on some LaCie/Seagate boards +(Example: 2Big/5Big Network v2, 2Big NAS). + +Required properties: +- compatible: "lacie,netxbig-gpio-ext". +- addr-gpios: GPIOs representing the address register (LSB -> MSB). +- data-gpios: GPIOs representing the data register (LSB -> MSB). +- enable-gpio: latches the new configuration (address, data) on raising edge. + +Example: + +netxbig_gpio_ext: netxbig-gpio-ext { + compatible = "lacie,netxbig-gpio-ext"; + + addr-gpios = <&gpio1 15 GPIO_ACTIVE_HIGH + &gpio1 16 GPIO_ACTIVE_HIGH + &gpio1 17 GPIO_ACTIVE_HIGH>; + data-gpios = <&gpio1 12 GPIO_ACTIVE_HIGH + &gpio1 13 GPIO_ACTIVE_HIGH + &gpio1 14 GPIO_ACTIVE_HIGH>; + enable-gpio = <&gpio0 29 GPIO_ACTIVE_HIGH>; +}; |