linux-kernel - Re: [PATCH v2 05/12] media: ipu-bridge: Use v4l2

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CANiDSCu=wU_Oi7CLPcYTC3Xf_pGbDroaVitPAiAj7ND5pXy-6g@mail.gmail.com>
Date: Tue, 8 Jul 2025 16:58:25 +0200
From: Ricardo Ribalda <ribalda@...omium.org>
To: Sakari Ailus <sakari.ailus@...ux.intel.com>
Cc: Hans de Goede <hdegoede@...hat.com>, 
	Laurent Pinchart <laurent.pinchart@...asonboard.com>, 
	Mauro Carvalho Chehab <mchehab@...nel.org>, Hans Verkuil <hverkuil@...all.nl>, 
	Greg Kroah-Hartman <gregkh@...uxfoundation.org>, Rob Herring <robh@...nel.org>, 
	Krzysztof Kozlowski <krzk+dt@...nel.org>, Conor Dooley <conor+dt@...nel.org>, 
	Linus Walleij <linus.walleij@...aro.org>, Bartosz Golaszewski <brgl@...ev.pl>, 
	"Rafael J. Wysocki" <rafael@...nel.org>, Len Brown <lenb@...nel.org>, linux-media@...r.kernel.org, 
	linux-kernel@...r.kernel.org, linux-usb@...r.kernel.org, 
	devicetree@...r.kernel.org, linux-gpio@...r.kernel.org, 
	linux-acpi@...r.kernel.org
Subject: Re: [PATCH v2 05/12] media: ipu-bridge: Use v4l2_fwnode for unknown rotations

On Tue, 8 Jul 2025 at 14:21, Sakari Ailus <sakari.ailus@...ux.intel.com> wrote:
>
> Hi Ricardo,
>
> On Tue, Jul 08, 2025 at 02:09:28PM +0200, Ricardo Ribalda wrote:
> > On Tue, 8 Jul 2025 at 11:22, Sakari Ailus <sakari.ailus@...ux.intel.com> wrote:
> > >
> > > Hi Ricardo,
> > >
> > > On Tue, Jul 08, 2025 at 11:16:25AM +0200, Ricardo Ribalda wrote:
> > > > Hi Sakari
> > > >
> > > > Thanks for your review
> > > >
> > > > On Mon, 7 Jul 2025 at 23:45, Sakari Ailus <sakari.ailus@...ux.intel.com> wrote:
> > > > >
> > > > > Hi Ricardo,
> > > > >
> > > > > On Thu, Jun 05, 2025 at 05:52:58PM +0000, Ricardo Ribalda wrote:
> > > > > > The v4l2_fwnode_device_properties contains information about the
> > > > > > rotation. Use it if the ssdb data is inconclusive.
> > > > >
> > > > > As SSDB and _PLD provide the same information, are they always aligned? Do
> > > > > you have any experience on how is this actually in firmware?
> > > >
> > > > Not really, in ChromeOS we are pretty lucky to control the firmware.
> > > >
> > > > @HdG Do you have some experience/opinion here?
> > > >
> > > > >
> > > > > _PLD is standardised so it would seem reasonable to stick to that -- if it
> > > > > exists. Another approach could be to pick the one that doesn't translate to
> > > > > a sane default (0°).
> > > >
> > > > I'd rather stick to the current prioritization unless there is a
> > > > strong argument against it. Otherwise there is a chance that we will
> > > > have regressions (outside CrOS)
> > >
> > > My point was rather there are no such rules currently for rotation: only
> > > SSDB was being used by the IPU bridge to obtain the rotation value,
> > > similarly only _PLD is consulted when it comes to orientation.
> >
> > So something like this:?
> >
> > static u32 ipu_bridge_parse_rotation(struct acpi_device *adev,
> >                                      struct ipu_sensor_ssdb *ssdb,
> >                                      struct
> > v4l2_fwnode_device_properties *props)
> > {
> >         if (props->rotation != V4L2_FWNODE_PROPERTY_UNSET)
> >                 return props->rotation;
> >
> >         switch (ssdb->degree) {
> >         case IPU_SENSOR_ROTATION_NORMAL:
> >                 return 0;
> >         case IPU_SENSOR_ROTATION_INVERTED:
> >                 return 180;
> >         }
> >
> >         dev_warn(ADEV_DEV(adev),
> >                  "Unknown rotation %d. Assume 0 degree rotation\n",
> >                  ssdb->degree);
>
> Maybe:
>
>         acpi_handle_warn(acpi_device_handle(adev), ...);
>
> ?
>
> >         return 0;
> > }
>
> Looks good to me. Maybe something similar for orientation?

Do you mean using ssdb also for orientation or using acpi_handle_warn?


I cannot find anything related to orientation for SSDB
https://github.com/coreboot/coreboot/blob/main/src/drivers/intel/mipi_camera/chip.h#L150

Am I looking in the right place?

Regards!
>
> --
> Regards,
>
> Sakari Ailus



-- 
Ricardo Ribalda