[Intel-gfx] [PATCH] drm/i915: set AUD_CONFIG N_value_index for DisplayPort

[Wu Fengguang]

On Thu, Jan 12, 2012 at 09:33:34AM -0800, Keith Packard wrote:
> On Tue, 10 Jan 2012 13:45:19 +0800, Wu Fengguang <fengguang.wu at intel.com> wrote:
> 
> > @@ -5943,6 +5947,7 @@ static void ironlake_write_eld(struct dr
> >  	if (intel_pipe_has_type(crtc, INTEL_OUTPUT_DISPLAYPORT)) {
> >  		DRM_DEBUG_DRIVER("ELD: DisplayPort detected\n");
> >  		eld[5] |= (1 << 2);	/* Conn_Type, 0x1 = DisplayPort */
> > +		I915_WRITE(aud_config, AUD_CONFIG_N_VALUE_INDEX); /* 0x1 = DP */
> >  	}
> 
> Do we need to clear this bit in the HDMI case? Or do we just trust the
> BIOS to either leave this bit zero or set it correctly?

I tried booting

1) with HDMI monitor plugged
2) plug HDMI monitor after BIOS boot

In both cases, I get the same AUD_CONFIG values for the host/sink matrix

                RX-V1800        SONY TV
ivybridge       0x00000000      0x00000000
ironlake        0x00000000      0x00000000

HDMI audio is working fine in all cases. So I guess it's fine to leave
HDMI as (unconfigured) 0.

Thanks,
Fengguang