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    SubjectRe: [PATCH v2 4/4] media: tc358746: add Toshiba TC358746 Parallel to CSI-2 bridge driver
    Hi Marco,

    On Tue, Sep 20, 2022 at 10:39:08AM +0200, Marco Felsch wrote:
    > Hi Sakari,
    >
    > On 22-09-19, Sakari Ailus wrote:
    > > On Mon, Sep 19, 2022 at 08:37:23PM +0300, Laurent Pinchart wrote:
    > > > > > > + ctrl = v4l2_ctrl_new_int_menu(&tc358746->ctrl_hdl, NULL,
    > > > > > > + V4L2_CID_LINK_FREQ, 0, 0,
    > > > > >
    > > > > > Shouldn't the max argument be set to the number of items minus 1 ?
    > > > >
    > > > > Right now I would keep it that way since the driver only supports one
    > > > > link-frequencies setting. So the ctrl don't let the userspace assume
    > > > > that there are more than one link-frequency.
    > > >
    > > > Good point. Can you add a short comment above the call to explain this ?
    > >
    > > Wouldn't it be just easier to do what Laurent suggested originally? The end
    > > result is the same, isn't it, and no comment needed?
    >
    > The end result depends on the device-tree given "link-frequencies"
    > property. The driver currently takes only one frequency but the
    > system-integrator of course can specify many more. In such case the 1st
    > is used. If I go with Laurent's comment, all frequencies would be shown
    > to the user-space but IMHO this shouldn't be the case since the driver
    > supports only 1 frequency.

    Yes, indeed. The driver can later be amended to support this.

    >
    > > >
    > > > > > > + link_frequencies);
    > > > > > > + if (ctrl)
    > > > > > > + ctrl->flags |= V4L2_CTRL_FLAG_READ_ONLY;
    > >
    > > Now that this is a bridge, this value presumably doesn't need to change.
    >
    > The value can change, e.g. if you have a few freq. to allow a wide range
    > of frame sizes. This can be the case to conform the emv tests. So there
    > can be a freq. for smaller frame sizes and one for larger frame sizes.

    Ack.

    --
    Regards,

    Sakari Ailus

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