[PATCH] drm/tegra: sor: Support for audio over HDMI

[Thierry Reding]

On Tue, Dec 04, 2018 at 11:33:48AM +0200, Jani Nikula wrote:
> On Tue, 04 Dec 2018, Thierry Reding <thierry.reding at gmail.com> wrote:
> > On Mon, Dec 03, 2018 at 06:05:07PM +0200, Jani Nikula wrote:
> >> On Mon, 03 Dec 2018, Thierry Reding <thierry.reding at gmail.com> wrote:
> >> > From: Thierry Reding <treding at nvidia.com>
> >> >
> >> > This code is very similar to the audio over HDMI support on older chips.
> >> > Interoperation with the audio codec is done via a pair of codec scratch
> >> > registers and an interrupt that is raised at the SOR when the codec has
> >> > written those registers.
> >> >
> >> > Signed-off-by: Thierry Reding <treding at nvidia.com>
> >> > ---
> >> >  drivers/gpu/drm/tegra/sor.c | 229 ++++++++++++++++++++++++++++++++++++
> >> >  drivers/gpu/drm/tegra/sor.h |  68 +++++++++++
> >> >  2 files changed, 297 insertions(+)
> >> >
> >> > diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
> >> > index b129da2e5afd..22a54434a757 100644
> >> > --- a/drivers/gpu/drm/tegra/sor.c
> >> > +++ b/drivers/gpu/drm/tegra/sor.c
> >> > @@ -19,6 +19,8 @@
> >> >  
> >> >  #include <soc/tegra/pmc.h>
> >> >  
> >> > +#include <sound/hda_verbs.h>
> >> > +
> >> >  #include <drm/drm_atomic_helper.h>
> >> >  #include <drm/drm_dp_helper.h>
> >> >  #include <drm/drm_panel.h>
> >> > @@ -407,6 +409,7 @@ struct tegra_sor {
> >> >  	const struct tegra_sor_soc *soc;
> >> >  	void __iomem *regs;
> >> >  	unsigned int index;
> >> > +	unsigned int irq;
> >> >  
> >> >  	struct reset_control *rst;
> >> >  	struct clk *clk_parent;
> >> > @@ -433,6 +436,11 @@ struct tegra_sor {
> >> >  
> >> >  	struct delayed_work scdc;
> >> >  	bool scdc_enabled;
> >> > +
> >> > +	struct {
> >> > +		unsigned int sample_rate;
> >> > +		unsigned int channels;
> >> > +	} audio;
> >> >  };
> >> >  
> >> >  struct tegra_sor_state {
> >> > @@ -2139,6 +2147,144 @@ tegra_sor_hdmi_setup_avi_infoframe(struct tegra_sor *sor,
> >> >  	return 0;
> >> >  }
> >> >  
> >> > +static void tegra_sor_write_eld(struct tegra_sor *sor)
> >> > +{
> >> > +	size_t length = drm_eld_size(sor->output.connector.eld), i;
> >> 
> >> This caught my eye, can't be right?
> >
> > Why do you think it's wrong? The length is the number of bytes that are
> > to be written to the HDA ELD buffer. This is pretty much the same across
> > all drivers that support HDMI audio (i915 and nouveau).
> >
> > Also, audio is definitely working with this patch, and the HDMI codecs
> > are showing the correct information in procfs.
> >
> > Can you elaborate?
> 
> Ugh, apologies for being too terse in my reply, as well as utterly
> wrong, and also too ashamed to admit after the fact where my fallacy
> was!

No worries.

Thierry
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 833 bytes
Desc: not available
URL: <https://lists.freedesktop.org/archives/dri-devel/attachments/20181204/a48615eb/attachment.sig>