Use the hdmi helper function [1] to calculate N and CTS.
[1] https://patchwork.kernel.org/patch/8091531/ ("video: hdmi: add helper function for N and CTS")
Signed-off-by: Philipp Zabel p.zabel@pengutronix.de --- drivers/gpu/drm/mediatek/mtk_hdmi_hw.c | 85 +++++++++------------------------- 1 file changed, 21 insertions(+), 64 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_hdmi_hw.c b/drivers/gpu/drm/mediatek/mtk_hdmi_hw.c index 6acbe77..9be50f5 100644 --- a/drivers/gpu/drm/mediatek/mtk_hdmi_hw.c +++ b/drivers/gpu/drm/mediatek/mtk_hdmi_hw.c @@ -492,65 +492,6 @@ static const struct hdmi_acr_n hdmi_rec_n_table[] = { { 0, { 4096, 6272, 6144 } }, /* all other TMDS clocks */ };
-/** - * hdmi_recommended_n() - Return N value recommended by HDMI specification - * @freq: audio sample rate in Hz - * @clock: rounded TMDS clock in kHz - */ -static unsigned int hdmi_recommended_n(unsigned int freq, unsigned int clock) -{ - const struct hdmi_acr_n *recommended; - unsigned int i; - - for (i = 0; i < ARRAY_SIZE(hdmi_rec_n_table) - 1; i++) { - if (clock == hdmi_rec_n_table[i].clock) - break; - } - recommended = hdmi_rec_n_table + i; - - switch (freq) { - case 32000: - return recommended->n[0]; - case 44100: - return recommended->n[1]; - case 48000: - return recommended->n[2]; - case 88200: - return recommended->n[1] * 2; - case 96000: - return recommended->n[2] * 2; - case 176400: - return recommended->n[1] * 4; - case 192000: - return recommended->n[2] * 4; - default: - return (128 * freq) / 1000; - } -} - -static unsigned int hdmi_mode_clock_to_hz(unsigned int clock) -{ - switch (clock) { - case 25175: - return 25174825; /* 25.2/1.001 MHz */ - case 74176: - return 74175824; /* 74.25/1.001 MHz */ - case 148352: - return 148351648; /* 148.5/1.001 MHz */ - case 296703: - return 296703297; /* 297/1.001 MHz */ - default: - return clock * 1000; - } -} - -static unsigned int hdmi_expected_cts(unsigned int audio_sample_rate, - unsigned int tmds_clock, unsigned int n) -{ - return DIV_ROUND_CLOSEST_ULL((u64)hdmi_mode_clock_to_hz(tmds_clock) * n, - 128 * audio_sample_rate); -} - static void do_hdmi_hw_aud_set_ncts(struct mtk_hdmi *hdmi, unsigned int n, unsigned int cts) { @@ -575,18 +516,34 @@ static void do_hdmi_hw_aud_set_ncts(struct mtk_hdmi *hdmi, unsigned int n, mtk_hdmi_write(hdmi, GRL_NCTS, val[i]); }
+static unsigned int hdmi_mode_clock_to_hz(unsigned int clock) +{ + switch (clock) { + case 25175: + return 25174825; /* 25.2/1.001 MHz */ + case 74176: + return 74175824; /* 74.25/1.001 MHz */ + case 148352: + return 148351648; /* 148.5/1.001 MHz */ + case 296703: + return 296703296; /* 297/1.001 MHz */ + default: + return clock * 1000; + } +} + void mtk_hdmi_hw_aud_set_ncts(struct mtk_hdmi *hdmi, unsigned int sample_rate, unsigned int clock) { - unsigned int n, cts; + struct hdmi_audio_n_cts n_cts;
- n = hdmi_recommended_n(sample_rate, clock); - cts = hdmi_expected_cts(sample_rate, clock, n); + hdmi_audio_get_coherent_n_cts(sample_rate, hdmi_mode_clock_to_hz(clock), + &n_cts);
dev_dbg(hdmi->dev, "%s: sample_rate=%u, clock=%d, cts=%u, n=%u\n", - __func__, sample_rate, clock, n, cts); + __func__, sample_rate, clock, n_cts.cts, n_cts.n);
mtk_hdmi_mask(hdmi, DUMMY_304, AUDIO_I2S_NCTS_SEL_64, AUDIO_I2S_NCTS_SEL); - do_hdmi_hw_aud_set_ncts(hdmi, n, cts); + do_hdmi_hw_aud_set_ncts(hdmi, n_cts.n, n_cts.cts); }