Hello,
On Tue, Jan 17, 2023 at 12:47:10PM +0100, Hans Verkuil wrote:
> More comments below:
>
> On 11/01/2023 03:24, Yuji Ishikawa wrote:
> > Add support to Video Input Interface on Toshiba Visconti ARM SoCs.
> > The interface device includes CSI2 Receiver,
> > frame grabber, video DMAC and image signal processor.
> > This patch provides the user interface layer.
> >
> > A driver instance provides three /dev/videoX device files;
> > one for RGB image capture, another one for optional RGB capture
> > with different parameters and the last one for RAW capture.
> >
> > Through the device files, the driver provides streaming (DMA-BUF) interface.
> > A userland application should feed DMA-BUF instances for capture buffers.
> >
> > The driver is based on media controller framework.
> > Its operations are roughly mapped to two subdrivers;
> > one for ISP and CSI2 receiver (yields 1 instance),
> > the other for capture (yields 3 instances for each capture mode).
> >
> > Signed-off-by: Yuji Ishikawa <yuji2.ishikawa@xxxxxxxxxxxxx>
> > ---
> > Changelog v2:
> > - Resend v1 because a patch exceeds size limit.
> >
> > Changelog v3:
> > - Adapted to media control framework
> > - Introduced ISP subdevice, capture device
> > - Remove private IOCTLs and add vendor specific V4L2 controls
> > - Change function name avoiding camelcase and uppercase letters
> >
> > Changelog v4:
> > - Split patches because the v3 patch exceeds size limit
> > - Stop using ID number to identify driver instance:
> > - Use dynamically allocated structure to hold HW specific context,
> > instead of static one.
> > - Call HW layer functions with the context structure instead of ID number
> > - Use pm_runtime to trigger initialization of HW
> > along with open/close of device files.
> >
> > Changelog v5:
> > - Fix coding style problems in viif.c
> > ---
> > drivers/media/platform/visconti/Makefile | 1 +
> > drivers/media/platform/visconti/viif.c | 545 ++++++++
> > drivers/media/platform/visconti/viif.h | 203 +++
> > .../media/platform/visconti/viif_capture.c | 1201 +++++++++++++++++
> > drivers/media/platform/visconti/viif_isp.c | 846 ++++++++++++
> > 5 files changed, 2796 insertions(+)
> > create mode 100644 drivers/media/platform/visconti/viif.c
> > create mode 100644 drivers/media/platform/visconti/viif.h
> > create mode 100644 drivers/media/platform/visconti/viif_capture.c
> > create mode 100644 drivers/media/platform/visconti/viif_isp.c
[snip]
> > +static int viif_s_edid(struct file *file, void *fh, struct v4l2_edid *edid)
> > +{
> > + struct viif_device *viif_dev = video_drvdata_to_capdev(file)->viif_dev;
> > + struct viif_subdev *viif_sd = viif_dev->sd;
> > +
> > + return v4l2_subdev_call(viif_sd->v4l2_sd, pad, set_edid, edid);
> > +}
>
> Has this driver been tested with an HDMI receiver? If not, then I would recommend
> dropping support for it until you actually can test with such hardware.
>
> The DV_TIMINGS API is for HDMI/DVI/DisplayPort etc. interfaces, it's not meant
> for CSI and similar interfaces.
More than that, for MC-based drivers, the video node should *never*
forward ioctls to a connected subdev. The *only* valid calls to
v4l2_subdev_call() in this file are
- to video.s_stream() in the start and stop streaming handler
- to pad.g_fmt() when starting streaming to validate that the connected
subdev outputs a format compatible with the format set on the video
capture device
That's it, nothing else, all other calls to v4l2_subdev_call() must be
dropped from the implementation of the video_device.
[snip]
--
Regards,
Laurent Pinchart
