[libcamera-devel] [PATCH 0/5] Enumerate CameraLens by following sensor's ancillary links

[Tomasz Figa]

On Tue, Nov 30, 2021 at 6:47 PM Hanlin Chen <hanlinchen at chromium.org> wrote:
>
> Hi Daniel,
>
> On Tue, Nov 30, 2021 at 7:03 AM Daniel Scally <djrscally at gmail.com> wrote:
> >
> > Hey Hanlin
> >
> > On 29/11/2021 11:42, Hanlin Chen wrote:
> > > On Fri, Nov 26, 2021 at 8:48 PM Laurent Pinchart
> > > <laurent.pinchart at ideasonboard.com> wrote:
> > >> Hi Han-lin,
> > >>
> > >> On Fri, Nov 26, 2021 at 07:32:51PM +0800, Hanlin Chen wrote:
> > >>> On Fri, Nov 26, 2021 at 2:44 PM Jean-Michel Hautbois wrote:
> > >>>> On 26/11/2021 01:31, Daniel Scally wrote:
> > >>>>> Hello All
> > >>>>>
> > >>>>> This series is an attempt at making the incoming VCM support a little more
> > >>>>> agnostic, by following the new style of media links described in my series to
> > >>>>> linux-media [0] to find VCMs connected to Sensors in libcamera. It's based on
> > >>>>> top of a series from Han-Lin [1] and another from Kate Hsuan [2] (both of which
> > >>>>> series are pretty neat, by the way)
> > >>>> Thanks to all three of you for this great work !
> > >>>>
> > >>>> How can I test it ? Which kernel for SGo2 is usable (A branch would be
> > >>>> great) ?
> > >>> Many thanks for the great work, Daniel!
> > >>> I just tested it on Chromebook with kernel v5.4, and it works perfectly.
> > >> Does it work out of the box, without a need for any kernel or firmware
> > >> change ? That would be great, it would certainly facilitate adoption.
> > >>
> > > I didn't change anything in the firmware or kernel, except for
> > > Daniel's patches ;-).
> >
> >
> > Excellent; glad it's working for you. Does that mean you guys are
> > including some reference between the sensor and vcm device in your ACPI
> > design then?
> >
> I guess so ;-|. It needs some time for the experts on our side to
> confirm this and see how we should merge them to ChromeOS.

Yes, we have the standard lens-focus DT property in the _DSD package:
https://review.coreboot.org/plugins/gitiles/coreboot/+/refs/heads/master/src/mainboard/google/poppy/variants/baseboard/include/baseboard/acpi/cam0.asl#38

> > >
> > >>>>> The general principle of the new links is an entity to entity link which will
> > >>>>> be connected by the kernel between a sensor's entity and an entity for a VCM
> > >>>>> device, where those entities have a fwnode match based on the "lens-focus"
> > >>>>> property against the sensor. These links are then discovered by libcamera and
> > >>>>> followed to create an instance of the CameraLens class, replacing the matching
> > >>>>> on driver/device names in Han-Lin's original series.
> > >>>>>
> > >>>>> With the CameraLens available to carry out the controlling of the VCM, I have
> > >>>>> pushed the controls to the pipeline handler and removed both all of that
> > >>>>> functionality (including the open()/close() of the VCM subdev) from Kate's
> > >>>>> work instead.
> > >>>>>
> > >>>>> Thanks
> > >>>>> Dan
> > >>>>>
> > >>>>> [0] https://patchwork.linuxtv.org/project/linux-media/list/?series=6792
> > >>>>> [1] https://patchwork.libcamera.org/project/libcamera/list/?series=2743
> > >>>>> [2] https://patchwork.libcamera.org/project/libcamera/list/?series=2750
> > >>>>>
> > >>>>> Daniel Scally (5):
> > >>>>>    libcamera: Add support for ancillary links to MediaLink
> > >>>>>    libcamera: media_device: Handle ancillary links in populateLinks()
> > >>>>>    libcamera: ipu3-cio2: Discover VCMs through ancillary links
> > >>>>>    ipa: ipu3: Send lens controls to pipeline handler
> > >>>>>    ipa: ipu3: af: Remove v4l2 interaction from AF algorithm
> > >>>>>
> > >>>>>   include/libcamera/internal/media_object.h | 10 +++++
> > >>>>>   include/linux/media.h                     |  1 +
> > >>>>>   src/ipa/ipu3/algorithms/af.cpp            | 29 +------------
> > >>>>>   src/ipa/ipu3/algorithms/af.h              |  3 --
> > >>>>>   src/ipa/ipu3/ipu3.cpp                     |  4 ++
> > >>>>>   src/libcamera/media_device.cpp            | 52 ++++++++++++++++-------
> > >>>>>   src/libcamera/media_object.cpp            | 24 ++++++++++-
> > >>>>>   src/libcamera/pipeline/ipu3/cio2.cpp      | 45 +++++++++++---------
> > >>>>>   8 files changed, 101 insertions(+), 67 deletions(-)
> > >>>>>
> > >> --
> > >> Regards,
> > >>
> > >> Laurent Pinchart