[libcamera-devel] [PATCH v2 18/27] android: camera_device: Don't assume all planes use the same fd

[Laurent Pinchart]

Hi Hiro,

On Mon, Sep 06, 2021 at 10:35:46PM +0900, Hirokazu Honda wrote:
> On Mon, Sep 6, 2021 at 4:38 PM Jean-Michel Hautbois wrote:
> > On 06/09/2021 04:00, Laurent Pinchart wrote:
> > > Now that libcamera correctly supports frame buffers with different
> > > dmabuf for each plane, remove the assumption that a single dmabuf is
> > > used.
> > >
> > > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > > Reviewed-by: Jean-Michel Hautbois <jeanmichel.hautbois at ideasonboard.com>
> > > ---
> > >  src/android/camera_device.cpp | 25 ++++++-------------------
> > >  1 file changed, 6 insertions(+), 19 deletions(-)
> > >
> > > diff --git a/src/android/camera_device.cpp b/src/android/camera_device.cpp
> > > index 8ca76719a50f..c64064106ccc 100644
> > > --- a/src/android/camera_device.cpp
> > > +++ b/src/android/camera_device.cpp
> > > @@ -749,25 +749,6 @@ FrameBuffer *CameraDevice::createFrameBuffer(const buffer_handle_t camera3buffer
> > >                                            libcamera::PixelFormat pixelFormat,
> > >                                            const libcamera::Size &size)
> > >  {
> > > -     FileDescriptor fd;
> > > -     /*
> > > -      * This assumes all the planes are in the same dmabuf.
> > > -      *
> > > -      * \todo Verify that this assumption holds, fstat() can be used to check
> > > -      * if two fds refer to the same dmabuf.
> > > -      */
> > > -     for (int i = 0; i < camera3buffer->numFds; i++) {
> > > -             if (camera3buffer->data[i] != -1) {
> > > -                     fd = FileDescriptor(camera3buffer->data[i]);
> > > -                     break;
> > > -             }
> > > -     }
> > > -
> > > -     if (!fd.isValid()) {
> > > -             LOG(HAL, Fatal) << "No valid fd";
> > > -             return nullptr;
> > > -     }
> > > -
> > >       CameraBuffer buf(camera3buffer, pixelFormat, size, PROT_READ);
> > >       if (!buf.isValid()) {
> > >               LOG(HAL, Fatal) << "Failed to create CameraBuffer";
> > > @@ -776,6 +757,12 @@ FrameBuffer *CameraDevice::createFrameBuffer(const buffer_handle_t camera3buffer
> > >
> > >       std::vector<FrameBuffer::Plane> planes(buf.numPlanes());
> > >       for (size_t i = 0; i < buf.numPlanes(); ++i) {
> 
> I think it is not guaranteed that numFds is necessarily the same as
> buf.numPlanes().

Oh ? What's the expected behaviour then ? Is there any documentation
about all this ?

> > > +             FileDescriptor fd{ camera3buffer->data[i] };
> > > +             if (!fd.isValid()) {
> > > +                     LOG(HAL, Fatal) << "No valid fd";
> > > +                     return nullptr;
> > > +             }
> > > +
> > >               planes[i].fd = fd;
> > >               planes[i].offset = buf.offset(i);
> > >               planes[i].length = buf.size(i);
> > >

-- 
Regards,

Laurent Pinchart