On Sat, 2009-04-04 at 18:25 -0400, Andy Walls wrote:
> On Sat, 2009-04-04 at 11:05 -0500, Mike Isely wrote:
> So my rough outline of an idea (which probably runs slightly afoul of
> Hans' media_controller device, but we don't have it yet):
>
> 1. Add a function to the v4l2 framework to iterate over all the
> v4l2_device's that are registered (if there isn't one already).
>
> 2. Add a method to the v4l2_device class to return the IR subdevice for
> a given v4l2_device:
>
> v4l2_subdev *v4l2_device_get_ir_subdev(v4l2_device *dev);
>
> and if it returns NULL, that device has no IR chip.
>
>
> 3. To the v4l2_subdev framework add:
>
> struct v4l2_subdev_ir_ops {
> (*enumerate) (v4l2_subdev *sd, /* bus_type, bus #, addr for Rx, addr for Tx */);
> (*claim) (v4l2_subdev *sd, /* claiming driver name string, going-away callback function pointer */);
> (*release) (v4l2_subdev *sd, /* handle */);
> bool (*is_claimed) (v4l2_subdev *sd, /* output string of the "owner" */);
> /* Or maybe just */
> (*send) (v4l2_subdev *sd, /* data buffer */);
> (*receive) (v4l2_subdev *sd, /* data buffer */);
> }
>
> and have the bridge driver support these. (I also had some in mind for
> the IR micro-controller debug/programming port, but the above will fit
> the task at hand I think.)
>
>
> OK so that's all a bit rough around the edges. The idea is a uniform
> call in for ir-kdb-i2c or lirc_foo or ir_foo to get at an IR chip behind
> a bridge device, that the bridge device driver itself cares about very
> little. *Except* ir driver modules would be coordinated by the bridge
> driver in what they can and cannot do to get at the IR device. This
> coordination prevents bad things on the bridge chip's I2C bus(es) or
> from having modules racing to get the IR device. That way whatever
> module the user loads will get first shot at claiming the IR chip. This
> also provides a discovery mechanism four use by ir driver modules that
> is informed by the bridge chip driver. I think lirc_foo can also still
> use it's current way of doing business too.
>
> It really just looks like a small subset of what Hans intended for the
> media controller, so maybe this would be a good chance to get some
> "lessons learned."
Oops. That leaves DTV only devices with IR out in the cold, unless they
start to implement a v4l2_device and IR v4l2_subdev as well, or unless
they were never used with ir-kbd-i2c in the first place.
Regards,
Andy
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