Re: [PATCH v3 3/3] input: touchscreen: st1232: add system wakeup support

Bui Duc Phuc
2026-04-03T11:39:54Z

Hi Dmitry, Geert,

Thank you, Dmitry, for the review and the explanation. You are
absolutely right; I realized the I2C core handles this automatically,
which is tại sao I dropped those changes in the v4 series [1] as Geert
mentioned.

Thank you, Geert, for pointing that out and for your support.

While working on this, I also noticed similar redundant wakeup
handling in the mpr121 driver and sent a cleanup patch to remove
it [2].

[1] https://lore.kernel.org/20260309000319.74880-1-phucduc.bui@gmail.com
[2] https://lore.kernel.org/all/20260309071413.92709-1-phucduc.bui@gmail.com/

Thanks,
Phuc

On Thu, Apr 2, 2026 at 1:56 PM Geert Uytterhoeven <geert@linux-m68k.org> wrote:
>
> Hi Dmitry,
>
> On Thu, 2 Apr 2026 at 07:17, Dmitry Torokhov <dmitry.torokhov@gmail.com> wrote:
> > On Fri, Mar 06, 2026 at 06:19:12PM +0700, phucduc.bui@gmail.com wrote:
> > > From: bui duc phuc <phucduc.bui@gmail.com>
> > >
> > > The ST1232 touchscreen controller can generate an interrupt when the
> > > panel is touched, which may be used as a wakeup source for the system.
> > >
> > > Add support for system wakeup by initializing the device wakeup
> > > capability in probe() based on the "wakeup-source" device property.
> > > When wakeup is enabled, the driver enables IRQ wake during suspend
> > > so that touch events can wake the system.
> > >
> > > If wakeup is not enabled, the driver retains the existing behavior of
> > > disabling the IRQ and powering down the controller during suspend.
> >
> > I do not believe this patch is needed: i2c core already handles
> > "wakeup-source" property and manages wakeup IRQ.
>
> No, it is not needed, as mentioned in the cover letter of v4[1],
> and as tested by me[2].
>
> [1] https://lore.kernel.org/20260309000319.74880-1-phucduc.bui@gmail.com
> [2] https://lore.kernel.org/CAMuHMdUqiaP=COTkKU_jK6Hdii+YJ5+zXnxFkOOnhLri5NakTw@mail.gmail.com
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like that.
> -- Linus Torvalds