On Mon, Sep 16, 2024 at 04:33:13PM +0200, Krzysztof Kozlowski wrote:
> On Fri, Sep 13, 2024 at 02:30:57PM +0200, Marek Behún wrote:
> > Extend the cznic,turris-omnia-leds binding with interrupts property,
> > specifying the global LED brightness changed by button press interrupt.
> >
> > Signed-off-by: Marek Behún <kabel@xxxxxxxxxx>
> > ---
> > .../devicetree/bindings/leds/cznic,turris-omnia-leds.yaml | 8 ++++++++
> > 1 file changed, 8 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/leds/cznic,turris-omnia-leds.yaml b/Documentation/devicetree/bindings/leds/cznic,turris-omnia-leds.yaml
> > index 34ef5215c150..f52f6304c79e 100644
> > --- a/Documentation/devicetree/bindings/leds/cznic,turris-omnia-leds.yaml
> > +++ b/Documentation/devicetree/bindings/leds/cznic,turris-omnia-leds.yaml
> > @@ -23,6 +23,12 @@ properties:
> > description: I2C slave address of the microcontroller.
> > maxItems: 1
> >
> > + interrupts:
> > + description:
> > + Specifier for the global LED brightness changed by front button press
> > + interrupt.
>
> This "front button press" concerns me that you just hooked here
> gpio-key. Are you sure that this is the physical interrupt line going to
> this device?
No no no, that is a different interrupt from the gpio-key.
The button can be configure in two modes:
- it can act like a GPIO to the CPU, forwarding press and release events
via the GPIO chip (so button press it is handled by CPU)
- can be set with
echo cpu >/sys/bus/i2c/devices/1-002a/front_button_mode
- pressing it will generate the INT_BUTTON_PRESSED interrupt from the
MCU
- it can change LED panel brightness (so button press is handled by MCU)
- this is the default mode, configured after boot
- can be set with
echo mcu >/sys/bus/i2c/devices/1-002a/front_button_mode
- pressing it will generate the INT_BRIGHTNESS_CHANGED interrupt
The INT_BUTTON_PRESSED and INT_BRIGHTNESS_CHANGED interrupt semantically
different (and also literally, they are at different bits). See
https://gitlab.nic.cz/turris/hw/omnia_hw_ctrl/-/blob/master/src/drivers/i2c_iface.h?ref_type=heads#L289-L321
Marek
