| Message ID | 20210126131239.8335-2-o.rempel@pengutronix.de |
|---|---|
| State | New |
| Headers | show |
| Series | add support for GPIO based counter | expand |
Hi Oleksij, thanks for your patch! On Tue, Jan 26, 2021 at 2:15 PM Oleksij Rempel <o.rempel@pengutronix.de> wrote: > Add binding for the pulse counter node > > Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> (...) > +properties: > + compatible: > + const: virtual,pulse-counter What is so virtual about this? The device seems very real. However it is certainly a GPIO counter. I would call it "gpio-counter" simply. Define: $nodename: pattern: "^counter(@.*)?$" > + counter-0 { counter@0 { > + counter-1 { counter@1 { Thanks! Linus Walleij
On Thu, Jan 28, 2021 at 09:17:23AM +0100, Linus Walleij wrote: > Hi Oleksij, > > thanks for your patch! > > On Tue, Jan 26, 2021 at 2:15 PM Oleksij Rempel <o.rempel@pengutronix.de> wrote: > > > Add binding for the pulse counter node > > > > Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> > (...) > > > +properties: > > + compatible: > > + const: virtual,pulse-counter > > What is so virtual about this? The device seems very real. Currently there are two ways: 1. use "virtual" or "linux" vendor. Same as "virtual,mdio-gpio" 2. Extend the list of "not vendor" prefixes in the prefixes list: Documentation/devicetree/bindings/vendor-prefixes.yaml Since both ways seems to be valid, i personally prefer to use existing prefix instead of maintaining the vendor-prefixes.yaml @Rob, what do you prefer? > However it is certainly a GPIO counter. This was my first implementation. @Jonathan you suggest to use GPIO-free way, can you and Linus please decide what is the way to go. I personally can imagine that this driver can be attached to any IRQ source, including drivers/iio/trigger/iio-trig-sysfs.c > I would call it "gpio-counter" simply. > > Define: > $nodename: > pattern: "^counter(@.*)?$" > > > + counter-0 { > > counter@0 { > > > + counter-1 { > > counter@1 { In this case the dtc compiler will say: /counter@0: node has a unit name, but no reg property Regards, Oleksij -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
On Thu, Jan 28, 2021 at 02:39:22PM +0100, Oleksij Rempel wrote: > On Thu, Jan 28, 2021 at 09:17:23AM +0100, Linus Walleij wrote: > > Hi Oleksij, > > > > thanks for your patch! > > > > On Tue, Jan 26, 2021 at 2:15 PM Oleksij Rempel <o.rempel@pengutronix.de> wrote: > > > > > Add binding for the pulse counter node > > > > > > Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> > > (...) > > > > > +properties: > > > + compatible: > > > + const: virtual,pulse-counter > > > > What is so virtual about this? The device seems very real. > > Currently there are two ways: > 1. use "virtual" or "linux" vendor. Same as "virtual,mdio-gpio" virtual is used by exactly one case. linux for a few more, mostly linux,spdif-dit and extcon (deprecated). > 2. Extend the list of "not vendor" prefixes in the prefixes list: > Documentation/devicetree/bindings/vendor-prefixes.yaml Pretty sure that says 'DON'T ADD MORE'. Maybe I forgot to scream it. > > Since both ways seems to be valid, i personally prefer to use existing > prefix instead of maintaining the vendor-prefixes.yaml > > @Rob, what do you prefer? For vendorless bindings, no vendor prefix! 'gpio-counter' if only gpio interfaced. No idea what other options would be. > > > However it is certainly a GPIO counter. > > This was my first implementation. @Jonathan you suggest to use GPIO-free > way, can you and Linus please decide what is the way to go. > > I personally can imagine that this driver can be attached to any IRQ > source, including drivers/iio/trigger/iio-trig-sysfs.c > > > I would call it "gpio-counter" simply. > > > > Define: > > $nodename: > > pattern: "^counter(@.*)?$" > > > > > + counter-0 { > > > > counter@0 { > > > > > + counter-1 { > > > > counter@1 { > > In this case the dtc compiler will say: > /counter@0: node has a unit name, but no reg property counter-0 then. > > Regards, > Oleksij > -- > Pengutronix e.K. | | > Steuerwalder Str. 21 | http://www.pengutronix.de/ | > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
diff --git a/Documentation/devicetree/bindings/counter/pulse-counter.yaml b/Documentation/devicetree/bindings/counter/pulse-counter.yaml new file mode 100644 index 000000000000..8a82091edd65 --- /dev/null +++ b/Documentation/devicetree/bindings/counter/pulse-counter.yaml @@ -0,0 +1,52 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/counter/pulse-counter.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Pulse counter + +maintainers: + - Oleksij Rempel <o.rempel@pengutronix.de> + +description: | + A generic pulse counter to measure pulse frequency. It was developed and used + for agricultural devices to measure rotation speed of wheels or other tools. + Since the direction of rotation is not important, only one signal line is + needed. + +properties: + compatible: + const: virtual,pulse-counter + + interrupts: + maxItems: 1 + + gpios: + description: Optional diagnostic interface to measure signal level + maxItems: 1 + +required: + - compatible + - interrupts + +additionalProperties: false + +examples: + - | + + #include <dt-bindings/interrupt-controller/irq.h> + #include <dt-bindings/gpio/gpio.h> + + counter-0 { + compatible = "virtual,pulse-counter"; + interrupts-extended = <&gpio 0 IRQ_TYPE_EDGE_RISING>; + }; + + counter-1 { + compatible = "virtual,pulse-counter"; + interrupts-extended = <&gpio 1 IRQ_TYPE_EDGE_RISING>; + gpios = <&gpio 1 GPIO_ACTIVE_HIGH>; + }; + +...
Add binding for the pulse counter node Signed-off-by: Oleksij Rempel <o.rempel@pengutronix.de> --- .../bindings/counter/pulse-counter.yaml | 52 +++++++++++++++++++ 1 file changed, 52 insertions(+) create mode 100644 Documentation/devicetree/bindings/counter/pulse-counter.yaml