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From: Kai-Heng Feng <kai.heng.feng@canonical.com>
Date: Fri, 12 Apr 2024 14:28:32 +0800
Message-ID: <CAAd53p54HYPZEbK2aKQXjZt0V0-u-+F+6yqFjLzSVZx5BXG91w@mail.gmail.com>
Subject: Re: [PATCH v2] HID: i2c-hid: wait for i2c touchpad deep-sleep to
 power-up transition
To: =?UTF-8?Q?=C5=81ukasz_Majczak?= <lma@chromium.org>
Cc: Johan Hovold <johan@kernel.org>, Jiri Kosina <jikos@kernel.org>, 
	Dmitry Torokhov <dtor@chromium.org>, Benjamin Tissoires <benjamin.tissoires@redhat.com>, 
	Douglas Anderson <dianders@chromium.org>, Hans de Goede <hdegoede@redhat.com>, 
	Maxime Ripard <mripard@kernel.org>, Johan Hovold <johan+linaro@kernel.org>, 
	linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, 
	Radoslaw Biernacki <rad@chromium.org>
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Hi =C5=81ukasz,

On Thu, Apr 11, 2024 at 10:23=E2=80=AFPM =C5=81ukasz Majczak <lma@chromium.=
org> wrote:
>
> > Sure, but what about other transactions that are initiated by the host
> > (e.g. SET_POWER)?
> >
> Somehow it is problematic only on reboot and works just fine on
> suspend/resume and
> set_power.
> I will dig more and try to find out what the difference is.

If cold boot doesn't have such issue, maybe I2C_HID_PWR_SLEEP
shouldn't be used by reboot?

Kai-Heng

>
> > Perhaps this hack at probe is enough for your use case, but is an
> > incomplete hack and at a minimum you'd need to add a comment explaining
> > why it is there.
> >
> You mean a comment in the code ?
>
> Lukasz