[PATCH v2 1/4] Input: Add driver for Cypress Generation 5 touchscreen

Alistair Francis alistair23 at gmail.com
Tue Dec 21 15:28:10 PST 2021


On Sun, Dec 19, 2021 at 8:18 AM Andreas Kemnade <andreas at kemnade.info> wrote:
>
> Hi,
>
> On Sun, 12 Dec 2021 21:45:48 -0800
> Dmitry Torokhov <dmitry.torokhov at gmail.com> wrote:
>
> [...]
> > > > This is also likely unsafe if controller is not completely shut off and
> > > > is capable of generating interrupts given input device is not yet
> > > > allocated.
> > >
> > > I have dropped the `IRQF_TRIGGER_FALLING |`
> > >
> > > I have tried to use level interrupts, but I can't get the device
> > > working with them.
> >
> > That is weird, does the interrupt controller support level interrupts?
> >
> I have set level interrupts via the devicetree,
> things seem to work on Kobo Clara HD:
> /proc/interrupts
> 203:      37402  gpio-mxc   6 Level     tt21000
>
>        touchscreen at 24 {
>                 compatible = "cypress,tt21000";
>                 reg = <0x24>;
>                 pinctrl-names = "default","sleep";
>                 pinctrl-0 = <&pinctrl_cyttsp5_gpio>;
>                 pinctrl-1 = <&pinctrl_cyttsp5_gpio_sleep>;
>                 interrupt-parent = <&gpio5>;
>                 interrupts = <6 IRQ_TYPE_LEVEL_LOW>;
>                 reset-gpios = <&gpio5 13 GPIO_ACTIVE_LOW>;
>         };

I have tried using IRQ_TYPE_LEVEL_LOW as well, but the device doesn't
start correctly and the commands time out.

It works fine with IRQ_TYPE_EDGE_FALLING though.

Alistair

>
> Regards,
> Andreas



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