[PATCH 2/4] drm/bridge: dw-hdmi: add cec notifier support

[Russell King - ARM Linux]

On Fri, Jun 09, 2017 at 02:59:20PM +0200, Neil Armstrong wrote:
> On 05/30/2017 04:23 PM, Russell King wrote:
> > Add CEC notifier support to the HDMI bridge driver, so that the CEC
> > part of the IP can receive its physical address.
> > 
> > Signed-off-by: Russell King <rmk+kernel at armlinux.org.uk>
> > ---
> >  drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 22 +++++++++++++++++++++-
> >  1 file changed, 21 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > index 4e1f54a675d8..966422576c44 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
> > @@ -36,7 +36,10 @@
> >  #include "dw-hdmi.h"
> >  #include "dw-hdmi-audio.h"
> >  
> > +#include <media/cec-notifier.h>
> > +
> >  #define DDC_SEGMENT_ADDR	0x30
> > +
> >  #define HDMI_EDID_LEN		512
> >  
> >  enum hdmi_datamap {
> > @@ -173,6 +176,8 @@ struct dw_hdmi {
> >  
> >  	unsigned int reg_shift;
> >  	struct regmap *regm;
> > +
> > +	struct cec_notifier *cec_notifier;
> >  };
> >  
> >  #define HDMI_IH_PHY_STAT0_RX_SENSE \
> > @@ -1870,6 +1875,7 @@ static int dw_hdmi_connector_get_modes(struct drm_connector *connector)
> >  		hdmi->sink_is_hdmi = drm_detect_hdmi_monitor(edid);
> >  		hdmi->sink_has_audio = drm_detect_monitor_audio(edid);
> >  		drm_mode_connector_update_edid_property(connector, edid);
> > +		cec_notifier_set_phys_addr_from_edid(hdmi->cec_notifier, edid);
> >  		ret = drm_add_edid_modes(connector, edid);
> >  		/* Store the ELD */
> >  		drm_edid_to_eld(connector, edid);
> > @@ -2108,11 +2114,16 @@ static irqreturn_t dw_hdmi_irq(int irq, void *dev_id)
> >  	 * ask the source to re-read the EDID.
> >  	 */
> >  	if (intr_stat &
> > -	    (HDMI_IH_PHY_STAT0_RX_SENSE | HDMI_IH_PHY_STAT0_HPD))
> > +	    (HDMI_IH_PHY_STAT0_RX_SENSE | HDMI_IH_PHY_STAT0_HPD)) {
> >  		__dw_hdmi_setup_rx_sense(hdmi,
> >  					 phy_stat & HDMI_PHY_HPD,
> >  					 phy_stat & HDMI_PHY_RX_SENSE);
> >  
> > +		if ((phy_stat & (HDMI_PHY_RX_SENSE | HDMI_PHY_HPD)) == 0)
> > +			cec_notifier_set_phys_addr(hdmi->cec_notifier,
> > +						   CEC_PHYS_ADDR_INVALID);
> > +	}
> > +
> >  	if (intr_stat & HDMI_IH_PHY_STAT0_HPD) {
> >  		dev_dbg(hdmi->dev, "EVENT=%s\n",
> >  			phy_int_pol & HDMI_PHY_HPD ? "plugin" : "plugout");
> > @@ -2365,6 +2376,12 @@ __dw_hdmi_probe(struct platform_device *pdev,
> >  	if (ret)
> >  		goto err_iahb;
> >  
> > +	hdmi->cec_notifier = cec_notifier_get(dev);
> > +	if (!hdmi->cec_notifier) {
> > +		ret = -ENOMEM;
> > +		goto err_iahb;
> > +	}
> > +
> >  	/*
> >  	 * To prevent overflows in HDMI_IH_FC_STAT2, set the clk regenerator
> >  	 * N and cts values before enabling phy
> > @@ -2437,6 +2454,9 @@ __dw_hdmi_probe(struct platform_device *pdev,
> >  		hdmi->ddc = NULL;
> >  	}
> >  
> > +	if (hdmi->cec_notifier)
> > +		cec_notifier_put(hdmi->cec_notifier);
> > +
> >  	clk_disable_unprepare(hdmi->iahb_clk);
> >  err_isfr:
> >  	clk_disable_unprepare(hdmi->isfr_clk);
> > 
> 
> Hi Archit,
> 
> I think this one could go through drm-next since it's quite
> standalone and will reduce the DW-HDMI CEC patchset and dependencies.

Not a good idea.  If you read all the comments, Hans is suggesting that
CEC should be part of dw-hdmi itself, not stand-alone.  That would mean
this patch probably changes - basically, with CEC support built-in to
dw-hdmi, we don't need the notifier stuff.

So, I'd suggest _not_ merging it at the moment, because the patch could
well become obsolete.

Wait until the CEC changes that Hans has talked about have hit mainline
and I've had a chance to rework this for those.  We're waiting on Mauro
for that at the moment.

(I do find it rather frustrating that CEC seems to evolve very rapidly,
it makes it quite difficult to publish a patch set, and get it merged.)

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