From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
To: Rajat Jain <rajatja@google.com>
Cc: gwendal@google.com, Thomas Zimmermann <tzimmermann@suse.de>,
seanpaul@google.com, David Airlie <airlied@linux.ie>,
linux-kernel@vger.kernel.org, Hans de Goede <hdegoede@redhat.com>,
rajatxjain@gmail.com, dri-devel@lists.freedesktop.org,
marcheau@google.com
Subject: Re: [PATCH v2 2/2] drm/privacy_screen_x86: Add entry for ChromeOS privacy-screen
Date: Mon, 20 Dec 2021 14:00:46 -0800 [thread overview]
Message-ID: <YcD9DkYLrdexyP0p@google.com> (raw)
In-Reply-To: <CACK8Z6FyvpjhHqh3PRfRFYAhVaxgkxBT_1SnYH0PkvNv5qwOvw@mail.gmail.com>
On Mon, Dec 20, 2021 at 12:29:18PM -0800, Rajat Jain wrote:
> Hello,
>
> On Mon, Dec 20, 2021 at 11:50 AM Dmitry Torokhov
> <dmitry.torokhov@gmail.com> wrote:
> >
> > On Fri, Dec 17, 2021 at 12:28:50PM -0800, Rajat Jain wrote:
> > > Add a static entry in the x86 table, to detect and wait for
> > > privacy-screen on some ChromeOS platforms.
> > >
> > > Please note that this means that if CONFIG_CHROMEOS_PRIVACY_SCREEN is
> > > enabled, and if "GOOG0010" device is found in ACPI, then the i915 probe
> > > shall return EPROBE_DEFER until a platform driver actually registers the
> > > privacy-screen: https://hansdegoede.livejournal.com/25948.html
> > >
> > > Signed-off-by: Rajat Jain <rajatja@google.com>
> > > ---
> > > v2: * Use #if instead of #elif
> > > * Reorder the patches in the series.
> > > * Rebased on drm-tip
> > >
> > > drivers/gpu/drm/drm_privacy_screen_x86.c | 22 ++++++++++++++++++++++
> > > 1 file changed, 22 insertions(+)
> > >
> > > diff --git a/drivers/gpu/drm/drm_privacy_screen_x86.c b/drivers/gpu/drm/drm_privacy_screen_x86.c
> > > index a2cafb294ca6..0c5699ad70a3 100644
> > > --- a/drivers/gpu/drm/drm_privacy_screen_x86.c
> > > +++ b/drivers/gpu/drm/drm_privacy_screen_x86.c
> > > @@ -47,6 +47,18 @@ static bool __init detect_thinkpad_privacy_screen(void)
> > > }
> > > #endif
> > >
> > > +#if IS_ENABLED(CONFIG_CHROMEOS_PRIVACY_SCREEN)
> > > +static bool __init detect_chromeos_privacy_screen(void)
> >
> > Does marking this __init work in case there is a deferral?
>
> Yes, I have verified that for Chromeos case, it is a deferral.
>
> > Can it happen
> > that privacy screen is a module and so will get loaded only after we
> > discarded __init sections.
>
> Perhaps. But I do not think that is a problem. All the functions and
> data in this file are in __init sections, and this entry is here to
> ensure that the drm probe will wait for the privacy screen driver
> (whenever it is loaded).
Ah, OK, we are not leaking detect() pointers outside this module.
> That is the reason, ideally we would want to
> somehow restrict the privacy screen to be built into the kernel so as
> to minimize the delay if any.
I understand, but we can not code to the config we expect to use on
Chrome OS, we need to make sure we cover all possibilities.
Thanks.
--
Dmitry
next prev parent reply other threads:[~2021-12-21 9:09 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-12-17 20:28 [PATCH v2 1/2] platform/chrome: Add driver for ChromeOS privacy-screen Rajat Jain
2021-12-17 20:28 ` [PATCH v2 2/2] drm/privacy_screen_x86: Add entry " Rajat Jain
2021-12-20 19:50 ` Dmitry Torokhov
2021-12-20 20:29 ` Rajat Jain
2021-12-20 22:00 ` Dmitry Torokhov [this message]
2021-12-20 19:42 ` [PATCH v2 1/2] platform/chrome: Add driver " Dmitry Torokhov
2021-12-20 20:21 ` Rajat Jain
2021-12-20 22:07 ` Dmitry Torokhov
2021-12-20 23:31 ` Rajat Jain
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YcD9DkYLrdexyP0p@google.com \
--to=dmitry.torokhov@gmail.com \
--cc=airlied@linux.ie \
--cc=dri-devel@lists.freedesktop.org \
--cc=gwendal@google.com \
--cc=hdegoede@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=marcheau@google.com \
--cc=rajatja@google.com \
--cc=rajatxjain@gmail.com \
--cc=seanpaul@google.com \
--cc=tzimmermann@suse.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).