Hi Arnaud,
Am Freitag, den 22.01.2016, 18:48 +0100 schrieb Arnaud Pouliquen:
> From: Moise Gergaud <moise.gergaud@xxxxxx>
>
> Add helper function to compute HDMI CTS and N parameters.
> Implementation is based on HDMI 1.4b specification.
>
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>
Reviewed-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
Tested-by: Philipp Zabel <p.zabel@xxxxxxxxxxxxxx>
> ---
> drivers/video/hdmi.c | 222 +++++++++++++++++++++++++++++++++++++++++++++++++++
> include/linux/hdmi.h | 22 +++++
> 2 files changed, 244 insertions(+)
>
> diff --git a/drivers/video/hdmi.c b/drivers/video/hdmi.c
> index 1626892..be8b8ed 100644
> --- a/drivers/video/hdmi.c
> +++ b/drivers/video/hdmi.c
> @@ -1242,3 +1242,225 @@ int hdmi_infoframe_unpack(union hdmi_infoframe *frame, void *buffer)
> return ret;
> }
> EXPORT_SYMBOL(hdmi_infoframe_unpack);
> +
> +/**
> + * audio clock regeneration (acr) parameters
> + * N and CTS computation are based on HDMI specification 1.4b
> + */
> +enum audio_rate {
> + HDMI_AUDIO_N_CTS_32KHZ,
> + HDMI_AUDIO_N_CTS_44_1KHZ,
> + HDMI_AUDIO_N_CTS_48KHZ,
> +};
> +
> +struct hdmi_audio_acr {
> + unsigned int tmds_clk;
> + struct hdmi_audio_n_cts n_cts;
> +};
> +
> +static const struct hdmi_audio_acr hdmi_audio_standard_acr[3][12] = {
> + { /*32 kHz*/
> + { 25174825, { 4576, 28125, 0 } }, /* 25,20/1.001 MHz */
> + { 25200000, { 4096, 25200, 0 } }, /* 25.20 MHz */
> + { 27000000, { 4096, 27000, 0 } }, /* 27.00 MHz */
> + { 27027000, { 4096, 27027, 0 } }, /* 27.00*1.001 MHz */
> + { 54000000, { 4096, 54000, 0 } }, /* 54.00 MHz */
> + { 54054000, { 4096, 54054, 0 } }, /* 54.00*1.001 MHz */
> + { 74175824, { 11648, 210937, 50 } }, /* 74.25/1.001 MHz */
> + { 74250000, { 4096, 74250, 0 } }, /* 74.25 MHz */
> + { 148351648, { 11648, 421875, 0 } }, /* 148.50/1.001 MHz */
> + { 148500000, { 4096, 148500, 0 } }, /* 148.50 MHz */
> + { 296703296, { 5824, 421875, 0 } }, /* 297/1.001 MHz */
297/1.001 is about 296703296.7. Should this be rounded to 296703297 ?
regards
Philipp
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