[PATCH v1] ASoC: rockchip: i2s_tdm: Re-add the set_sysclk callback
From: Detlev Casanova <detlev.casanova@collabora.com>
Date: 2025-01-17 16:31:55
Also in:
linux-rockchip, linux-sound, lkml
Subsystem:
arm/rockchip soc support, rockchip i2s tdm driver, sound, sound - soc layer / dynamic audio power management (asoc), the rest · Maintainers:
Heiko Stuebner, Nicolas Frattaroli, Jaroslav Kysela, Takashi Iwai, Liam Girdwood, Mark Brown, Linus Torvalds
In commit
9e2ab4b18ebd ("ASoC: rockchip: i2s-tdm: Fix inaccurate sampling rates"),
the set_sysclk callback was removed as considered unused as the mclk rate
can be set in the hw_params callback.
The difference between hw_params and set_sysclk is that the former is
called with the audio sampling rate set in the params (e.g.: 48000 Hz)
while the latter is called with a clock rate already computed with
sampling_rate * mclk-fs (e.g.: 48000 * 256)
For HDMI audio using the Rockchip I2S TDM driver, the mclk-fs value must
be set to 128 instead of the default 256, and that value is set in the
device tree at the machine driver level (like a simple-audio-card
compatible node).
Therefore, the i2s_tdm driver has no idea that another mclk-fs value can
be configured and simply computes the mclk rate in the hw_params callback
with DEFAULT_MCLK_FS * params_rate(params), which is wrong for HDMI
audio.
Re-add the set_sysclk callback so that the mclk rate is computed by the
machine driver which has the correct mclk-fs value set in its device tree
node.
Fixes: 9e2ab4b18ebd ("ASoC: rockchip: i2s-tdm: Fix inaccurate sampling rates")
Signed-off-by: Detlev Casanova <detlev.casanova@collabora.com>
---
sound/soc/rockchip/rockchip_i2s_tdm.c | 31 +++++++++++++++++++++++++--
1 file changed, 29 insertions(+), 2 deletions(-)
diff --git a/sound/soc/rockchip/rockchip_i2s_tdm.c b/sound/soc/rockchip/rockchip_i2s_tdm.c
index d1f28699652f..acd75e48851f 100644
--- a/sound/soc/rockchip/rockchip_i2s_tdm.c
+++ b/sound/soc/rockchip/rockchip_i2s_tdm.c@@ -22,7 +22,6 @@ #define DRV_NAME "rockchip-i2s-tdm" -#define DEFAULT_MCLK_FS 256 #define CH_GRP_MAX 4 /* The max channel 8 / 2 */ #define MULTIPLEX_CH_MAX 10
@@ -70,6 +69,8 @@ struct rk_i2s_tdm_dev { bool has_playback; bool has_capture; struct snd_soc_dai_driver *dai; + unsigned int mclk_rx_freq; + unsigned int mclk_tx_freq; }; static int to_ch_num(unsigned int val)
@@ -645,6 +646,27 @@ static int rockchip_i2s_trcm_mode(struct snd_pcm_substream *substream, return 0; } +static int rockchip_i2s_tdm_set_sysclk(struct snd_soc_dai *cpu_dai, int stream, + unsigned int freq, int dir) +{ + struct rk_i2s_tdm_dev *i2s_tdm = to_info(cpu_dai); + + if (i2s_tdm->clk_trcm) { + i2s_tdm->mclk_tx_freq = freq; + i2s_tdm->mclk_rx_freq = freq; + } else { + if (stream == SNDRV_PCM_STREAM_PLAYBACK) + i2s_tdm->mclk_tx_freq = freq; + else + i2s_tdm->mclk_rx_freq = freq; + } + + dev_dbg(i2s_tdm->dev, "The target mclk_%s freq is: %d\n", + stream ? "rx" : "tx", freq); + + return 0; +} + static int rockchip_i2s_tdm_hw_params(struct snd_pcm_substream *substream, struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
@@ -659,15 +681,19 @@ static int rockchip_i2s_tdm_hw_params(struct snd_pcm_substream *substream, if (i2s_tdm->clk_trcm == TRCM_TX) { mclk = i2s_tdm->mclk_tx; + mclk_rate = i2s_tdm->mclk_tx_freq; } else if (i2s_tdm->clk_trcm == TRCM_RX) { mclk = i2s_tdm->mclk_rx; + mclk_rate = i2s_tdm->mclk_rx_freq; } else if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { mclk = i2s_tdm->mclk_tx; + mclk_rate = i2s_tdm->mclk_tx_freq; } else { mclk = i2s_tdm->mclk_rx; + mclk_rate = i2s_tdm->mclk_rx_freq; } - err = clk_set_rate(mclk, DEFAULT_MCLK_FS * params_rate(params)); + err = clk_set_rate(mclk, mclk_rate); if (err) return err;
@@ -827,6 +853,7 @@ static const struct snd_soc_dai_ops rockchip_i2s_tdm_dai_ops = { .hw_params = rockchip_i2s_tdm_hw_params, .set_bclk_ratio = rockchip_i2s_tdm_set_bclk_ratio, .set_fmt = rockchip_i2s_tdm_set_fmt, + .set_sysclk = rockchip_i2s_tdm_set_sysclk, .set_tdm_slot = rockchip_dai_tdm_slot, .trigger = rockchip_i2s_tdm_trigger, };
--
2.48.1