Re: [PATCH] ASoC: rockchip: i2s-tdm: Use param rate if not provided by set_sysclk

From: Alexandre Belloni

Date: Thu Feb 19 2026 - 04:37:36 EST


Hello,

On 18/02/2026 15:18:34-0500, Detlev Casanova wrote:
> Drivers will not always call set_sysclk() for all clocks, especially when
> default mclk-fs can be used.
> When that is the case, use the clock rate set in the params multiplied by the
> default mclk-fs.
>
> Fixes: 5323186e2e8d ("ASoC: rockchip: i2s_tdm: Re-add the set_sysclk callback")
> Signed-off-by: Detlev Casanova <detlev.casanova@xxxxxxxxxxxxx>
> ---
> sound/soc/rockchip/rockchip_i2s_tdm.c | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/sound/soc/rockchip/rockchip_i2s_tdm.c b/sound/soc/rockchip/rockchip_i2s_tdm.c
> index 770b9bfbb384..fc52149ed6ae 100644
> --- a/sound/soc/rockchip/rockchip_i2s_tdm.c
> +++ b/sound/soc/rockchip/rockchip_i2s_tdm.c
> @@ -22,6 +22,7 @@
>
> #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
>
> @@ -665,6 +666,15 @@ static int rockchip_i2s_tdm_hw_params(struct snd_pcm_substream *substream,
> mclk_rate = i2s_tdm->mclk_rx_freq;
> }
>
> + /*
> + * When the dai/component driver doesn't need to set mclk-fs for a specific
> + * clock, it can skip the call to set_sysclk() for that clock.
> + * In that case, simply use the clock rate from the params and multiply it by
> + * the default mclk-fs value.
> + */
> + if (!mclk_rate)
> + mclk_rate = DEFAULT_MCLK_FS * params_rate(params);
> +

Maybe this could be set as the default value of i2s_tdm->mclk_rx_freq
and i2s_tdm->mclk_tx_freq in rockchip_i2s_tdm_probe instead of relying
on it being 0 and testing later on?

--
Alexandre Belloni, co-owner and COO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com