On Wed, Jun 07, 2017 at 03:26:03PM -0500, Rob Herring wrote:
> On Mon, May 29, 2017 at 04:45:38PM +0200, Mylène Josserand wrote:
> > Add the Cypress TrueTouch Generation 5 touchscreen device tree bindings
> > documentation. It can use I2C or SPI bus.
> > This touchscreen can handle some defined zone that are designed and
> > sent as button. To be able to customize the keycode sent, the
> > "linux,code" property in a "button" sub-node can be used.
>
> "documentation" twice in the subject makes for a long subject.
> The preferred subject prefix is "dt-bindings: input: ..."
>
> >
> > Signed-off-by: Mylène Josserand <[email protected]>
> > ---
> > .../bindings/input/touchscreen/cyttsp5.txt | 55
> > ++++++++++++++++++++++
>
> cypress,cyttsp5.txt matching the compatible is preferred.
>
> > 1 file changed, 55 insertions(+)
> > create mode 100644
> > Documentation/devicetree/bindings/input/touchscreen/cyttsp5.txt
> >
> > diff --git
> > a/Documentation/devicetree/bindings/input/touchscreen/cyttsp5.txt
> > b/Documentation/devicetree/bindings/input/touchscreen/cyttsp5.txt
> > new file mode 100644
> > index 000000000000..713a377b5039
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/input/touchscreen/cyttsp5.txt
> > @@ -0,0 +1,55 @@
> > +* Cypress cyttsp touchscreen controller, generation 5
> > +
> > +Required properties:
> > + - compatible : must be "cypress,cyttsp5"
> > + - reg : Device I2C address or SPI chip select number
> > + - interrupt-parent : the phandle for the gpio controller
> > + (see interrupt binding[0]).
> > + - interrupts : (gpio) interrupt to which the chip is
> > connected
> > + (see interrupt binding[0]).
> > +
> > +Optional properties (many of them coming from touchscreen binding[1]):
> > + - reset-gpios : the reset gpio the chip is connected to
> > + (see GPIO binding[2] for more details).
> > + - touchscreen-size-x : horizontal resolution of touchscreen (in
> > pixels)
>
> Just "see ./touchscreen.txt" is enough description.
>
> > + - touchscreen-size-y : vertical resolution of touchscreen (in pixels)
> > + - touchscreen-fuzz-x : horizontal noise value of the absolute input
> > device
> > + (in pixels)
> > + - touchscreen-fuzz-y : vertical noise value of the absolute input
> > device
> > + (in pixels)
> > +
> > +This touchscreen can handle some buttons that are touchscreen's defined
> > zones.
> > +Each button's event can be customized using a sub-node properties:
> > + - linux,code: Keycode to emit.
> > +
> > +[0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
> > +[1]: Documentation/devicetree/bindings/input/touchscreen/touchscreen.txt
> > +[2]: Documentation/devicetree/bindings/gpio/gpio.txt
> > +
> > +Example:
> > +&i2c0 {
> > + [...]
> > +
> > + tsc@24 {
>
> touchscreen@24
>
> > + compatible = "cypress,cyttsp5";
> > + reg = <0x24>;
> > +
> > + pinctrl-names = "default";
> > + pinctrl-0 = <&tp_reset_ds203>;
> > + interrupt-parent = <&pio>;
> > + interrupts = <1 5 IRQ_TYPE_LEVEL_LOW>;
> > + reset-gpios = <&pio 7 1 GPIO_ACTIVE_HIGH>;
> > +
> > + button@0 {
>
> unit addresses need a reg property. If 0,1,2 are meaningful numbers for
> the hardware, then it makes sense to add here.
Another option would be just say:
linux,keycodes = <KEY_HOMEPAGE>, <KEY_MENU>, <KEY_BACK>;
I am wondering though: you read number of button supported by the device
from HID_SYSINFO_BTN_OFFSET, can you also get button assignment form
the device as well?
And the biggest question of all: since you refer to HID descriptors in
your driver, is it a HID device and should it be driven by HID susbystem
instead of relying on a custom driver?
>
> > + linux,code = <KEY_HOMEPAGE>;
> > + };
> > +
> > + button@1 {
> > + linux,code = <KEY_MENU>;
> > + };
> > +
> > + button@2 {
> > + linux,code = <KEY_BACK>;
> > + };
> > + };
> > +};
> > --
> > 2.11.0
> >
Thanks.
--
Dmitry
