Re: HDMI monitor hot remove handling

[Wu Fengguang <fengguang.wu@intel.com>]

On Mon, Nov 14, 2011 at 10:05:05AM +0800, Zhenyu Wang wrote:
> On 2011.11.11 16:50:41 +0800, Wu Fengguang wrote:
> > > > > I still think you should do those in hot_plug(), to call detect() for current
> > > > > status, write eld and set specific audio enable/disable bit for all audio stuff.
> > > > > Just my sense, you may send RFC patch for other's comment. 
> > 
> > > yeah, mode_set() will only be in normal mode setting path and taking current
> > > monitor's audio capability, but not on hot removal path. And if connector's DPMS off,
> > > does audio need to care? I think no, as user might still like to hear sound, right? ;)
> > > 
> > > So looks currently nobody cares for hot removal, you need to set that by
> > > yourself somewhere.
> > 
> > Zhenyu, according to your comments, here is the patch, tested OK on
> > HDMI :)  DP not tested yet.
> 
> Well, I don't think I suggested a new hook for hot removal. ;)

Yes, sorry.

> You know that hot_plug() hook is intel encoder thing, which is the place
> I think you can do audio config stuff. 

The problem is, ->hot_plug() is called at the very beginning, before
->detect() is called. If doing the hot remove notifications in
->hot_plug(), the patch will add an _extra_ loop to call into
->detect().

Why not insert the functionalities somewhere after ->detect() is
called and we already know it's a hot removal event?  That avoids
adding duplicate ->detect() calls.

Thanks,
Fengguang

> > 
> > This notifies the audio driver of the HDMI/DP monitor hot removal
> > event.
> > 
> > - clear SDVO_AUDIO_ENABLE/DP_AUDIO_OUTPUT_ENABLE
> > - clear ELD Valid bit
> > 
> > Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
> > ---
> >  drivers/gpu/drm/drm_crtc_helper.c |    4 ++++
> >  drivers/gpu/drm/i915/intel_dp.c   |   19 +++++++++++++++++++
> >  drivers/gpu/drm/i915/intel_drv.h  |    4 ++++
> >  drivers/gpu/drm/i915/intel_hdmi.c |   17 +++++++++++++++++
> >  include/drm/drm_crtc.h            |    1 +
> >  5 files changed, 45 insertions(+)
> > 
> > --- linux.orig/drivers/gpu/drm/i915/intel_dp.c	2011-11-11 16:42:58.000000000 +0800
> > +++ linux/drivers/gpu/drm/i915/intel_dp.c	2011-11-11 16:42:59.000000000 +0800
> > @@ -1984,6 +1984,24 @@ intel_dp_detect(struct drm_connector *co
> >  	return connector_status_connected;
> >  }
> >  
> > +static void intel_dp_hot_remove(struct drm_connector *connector)
> > +{
> > +	struct intel_dp *intel_dp = intel_attached_dp(connector);
> > +	struct drm_device *dev = intel_dp->base.base.dev;
> > +	struct drm_i915_private *dev_priv = dev->dev_private;
> > +	struct drm_crtc *crtc = intel_dp->base.base.crtc;
> > +	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
> > +
> > +	intel_dp->DP &= ~DP_AUDIO_OUTPUT_ENABLE;
> > +	I915_WRITE(intel_dp->output_reg, intel_dp->DP);
> > +	POSTING_READ(intel_dp->output_reg);
> > +	intel_wait_for_vblank(dev, intel_crtc->pipe);
> > +
> > +	connector->eld[0] = 0;
> > +	if (dev_priv->display.write_eld)
> > +		dev_priv->display.write_eld(connector, crtc);
> > +}
> > +
> >  static int intel_dp_get_modes(struct drm_connector *connector)
> >  {
> >  	struct intel_dp *intel_dp = intel_attached_dp(connector);
> > @@ -2143,6 +2161,7 @@ static const struct drm_connector_funcs 
> >  	.detect = intel_dp_detect,
> >  	.fill_modes = drm_helper_probe_single_connector_modes,
> >  	.set_property = intel_dp_set_property,
> > +	.hot_remove = intel_dp_hot_remove,
> >  	.destroy = intel_dp_destroy,
> >  };
> >  
> > --- linux.orig/drivers/gpu/drm/i915/intel_drv.h	2011-11-11 16:42:58.000000000 +0800
> > +++ linux/drivers/gpu/drm/i915/intel_drv.h	2011-11-11 16:42:59.000000000 +0800
> > @@ -382,6 +382,10 @@ extern void intel_fb_restore_mode(struct
> >  extern void intel_init_clock_gating(struct drm_device *dev);
> >  extern void intel_write_eld(struct drm_encoder *encoder,
> >  			    struct drm_display_mode *mode);
> > +extern void intel_hotplug_status(struct drm_device *dev,
> > +			  struct drm_connector *connector,
> > +			  struct drm_crtc *crtc,
> > +			  enum drm_connector_status status);
> >  extern void intel_cpt_verify_modeset(struct drm_device *dev, int pipe);
> >  
> >  #endif /* __INTEL_DRV_H__ */
> > --- linux.orig/drivers/gpu/drm/i915/intel_hdmi.c	2011-11-11 16:42:58.000000000 +0800
> > +++ linux/drivers/gpu/drm/i915/intel_hdmi.c	2011-11-11 16:42:59.000000000 +0800
> > @@ -352,6 +352,22 @@ intel_hdmi_detect(struct drm_connector *
> >  	return status;
> >  }
> >  
> > +static void intel_hdmi_hot_remove(struct drm_connector *connector)
> > +{
> > +	struct intel_hdmi *intel_hdmi = intel_attached_hdmi(connector);
> > +	struct drm_i915_private *dev_priv = connector->dev->dev_private;
> > +	u32 temp;
> > +
> > +	temp = I915_READ(intel_hdmi->sdvox_reg);
> > +	I915_WRITE(intel_hdmi->sdvox_reg, temp & ~SDVO_AUDIO_ENABLE);
> > +	POSTING_READ(intel_hdmi->sdvox_reg);
> > +
> > +	connector->eld[0] = 0;
> > +	if (dev_priv->display.write_eld)
> > +		dev_priv->display.write_eld(connector,
> > +					    intel_hdmi->base.base.crtc);
> > +}
> > +
> >  static int intel_hdmi_get_modes(struct drm_connector *connector)
> >  {
> >  	struct intel_hdmi *intel_hdmi = intel_attached_hdmi(connector);
> > @@ -461,6 +477,7 @@ static const struct drm_connector_funcs 
> >  	.detect = intel_hdmi_detect,
> >  	.fill_modes = drm_helper_probe_single_connector_modes,
> >  	.set_property = intel_hdmi_set_property,
> > +	.hot_remove = intel_hdmi_hot_remove,
> >  	.destroy = intel_hdmi_destroy,
> >  };
> >  
> > --- linux.orig/drivers/gpu/drm/drm_crtc_helper.c	2011-11-11 16:42:58.000000000 +0800
> > +++ linux/drivers/gpu/drm/drm_crtc_helper.c	2011-11-11 16:42:59.000000000 +0800
> > @@ -907,6 +907,10 @@ static void output_poll_execute(struct w
> >  			      old_status, connector->status);
> >  		if (old_status != connector->status)
> >  			changed = true;
> > +		if (old_status == connector_status_connected &&
> > +		    connector->status == connector_status_disconnected)
> > +			connector->funcs->hot_remove(connector);
> > +
> >  	}
> >  
> >  	mutex_unlock(&dev->mode_config.mutex);
> > --- linux.orig/include/drm/drm_crtc.h	2011-11-11 16:42:58.000000000 +0800
> > +++ linux/include/drm/drm_crtc.h	2011-11-11 16:42:59.000000000 +0800
> > @@ -419,6 +419,7 @@ struct drm_connector_funcs {
> >  	int (*fill_modes)(struct drm_connector *connector, uint32_t max_width, uint32_t max_height);
> >  	int (*set_property)(struct drm_connector *connector, struct drm_property *property,
> >  			     uint64_t val);
> > +	void (*hot_remove)(struct drm_connector *connector);
> >  	void (*destroy)(struct drm_connector *connector);
> >  	void (*force)(struct drm_connector *connector);
> >  };
> 
> -- 
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