[PATCH RFC 4/5] drm/bridge: add dw-hdmi cec driver using Hans Verkil's CEC code

[Russell King - ARM Linux]

On Tue, Aug 23, 2016 at 09:21:17AM +0200, Hans Verkuil wrote:
> Hi Russell,
> 
> On 08/12/2016 04:15 PM, Russell King wrote:
> > Add a CEC driver for the dw-hdmi hardware using Hans Verkil's CEC
> > implementation.
> > 
> > Signed-off-by: Russell King <rmk+kernel at armlinux.org.uk>
> > ---
> >  drivers/gpu/drm/bridge/Kconfig            |   7 +
> >  drivers/gpu/drm/bridge/Makefile           |   1 +
> >  drivers/gpu/drm/bridge/dw-hdmi-cec.c      | 344 ++++++++++++++++++++++++++++++
> >  drivers/gpu/drm/bridge/dw-hdmi.c          |  64 +++++-
> >  include/linux/platform_data/dw_hdmi-cec.h |  16 ++
> >  5 files changed, 421 insertions(+), 11 deletions(-)
> >  create mode 100644 drivers/gpu/drm/bridge/dw-hdmi-cec.c
> >  create mode 100644 include/linux/platform_data/dw_hdmi-cec.h
> > 
> 
> <snip>
> 
> > +static unsigned int parse_hdmi_addr(const struct edid *edid)
> > +{
> > +	if (!edid || edid->extensions == 0)
> > +		return (u16)~0;
> > +
> > +	return cec_get_edid_phys_addr((u8 *)edid,
> > +				EDID_LENGTH * (edid->extensions + 1), NULL);
> > +}
> > +
> > +static int dw_hdmi_cec_notify(struct notifier_block *nb, unsigned long event,
> > +			      void *data)
> > +{
> > +	struct dw_hdmi_cec *cec = container_of(nb, struct dw_hdmi_cec, nb);
> > +	union hdmi_event *event_block = data;
> > +	unsigned int phys;
> > +
> > +	dev_info(event_block->base.source, "event %lu\n", event);
> > +
> > +	if (event_block->base.source != cec->adap->devnode.parent)
> > +		return NOTIFY_OK;
> > +
> > +	switch (event) {
> > +	case HDMI_CONNECTED:
> > +		break;
> > +
> > +	case HDMI_DISCONNECTED:
> > +		cec_s_phys_addr(cec->adap, CEC_PHYS_ADDR_INVALID, false);
> > +		break;
> > +
> > +	case HDMI_NEW_EDID:
> > +		phys = parse_hdmi_addr(event_block->edid.edid);
> > +		cec_s_phys_addr(cec->adap, phys, false);
> > +		break;
> > +	}
> > +
> > +	return NOTIFY_OK;
> > +}
> 
> Wouldn't it make a lot of sense to integrate this into the cec framework?
> 
> All you need is to pass an hdmi_notifier_dev as argument to cec_allocate_adapter()
> and you can integrate this.
> 
> If you are OK with that, then I can make patches for that.

It's not just about CEC.  It's also used for passing information between
the video and audio parts, so tying this into CEC is wrong.

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