On Friday, 24 January 2025 00:01:38 EST Dmitry Baryshkov wrote:
> On Thu, Jan 23, 2025 at 05:28:06PM -0500, Detlev Casanova wrote:
> > From: Sugar Zhang <sugar.zhang@xxxxxxxxxxxxxx>
> >
> > Register the dw-hdmi-qp bridge driver as an HDMI audio codec.
> >
> > The register values computation functions (for n) are based on the
> > downstream driver, as well as the register writing functions.
> >
> > The driver uses the generic HDMI Codec framework in order to implement
> > the HDMI audio support.
> >
> > Signed-off-by: Sugar Zhang <sugar.zhang@xxxxxxxxxxxxxx>
> > Signed-off-by: Detlev Casanova <detlev.casanova@xxxxxxxxxxxxx>
> > ---
> >
> > drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c | 424 +++++++++++++++++++
> > 1 file changed, 424 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c
> > b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c index
> > b281cabfe992e..f79d38de4c6c4 100644
> > --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c
> > +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi-qp.c
> > @@ -36,6 +36,66 @@
> >
> > #define SCRAMB_POLL_DELAY_MS 3000
> >
> > +/*
> > + * Unless otherwise noted, entries in this table are 100% optimization.
> > + * Values can be obtained from hdmi_compute_n() but that function is
> > + * slow so we pre-compute values we expect to see.
> > + *
> > + * All 32k and 48k values are expected to be the same (due to the way
> > + * the math works) for any rate that's an exact kHz.
> > + */
> > +static const struct dw_hdmi_audio_tmds_n {
> > + unsigned long tmds;
> > + unsigned int n_32k;
> > + unsigned int n_44k1;
> > + unsigned int n_48k;
> > +} common_tmds_n_table[] = {
> > + { .tmds = 25175000, .n_32k = 4096, .n_44k1 = 12854, .n_48k = 6144,
},
> > + { .tmds = 25200000, .n_32k = 4096, .n_44k1 = 5656, .n_48k = 6144, },
>
> These values do not seem to match the tables in HDMI, Appendix D. Is
> there any reason for that?
