ASoC: meson: axg-tdm-interface: fix mclk setup without mclk-fs

[ Upstream commit e3741a8d28 ]

By default, when mclk-fs is not provided, the tdm-interface driver
requests an MCLK that is 4x the bit clock, SCLK.

However there is no justification for this:

* If the codec needs MCLK for its operation, mclk-fs is expected to be set
  according to the codec requirements.
* If the codec does not need MCLK the minimum is 2 * SCLK, because this is
  minimum the divider between SCLK and MCLK can do.

Multiplying by 4 may cause problems because the PLL limit may be reached
sooner than it should, so use 2x instead.

Fixes: d60e4f1e4b ("ASoC: meson: add tdm interface driver")
Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Link: https://msgid.link/r/20240223175116.2005407-2-jbrunet@baylibre.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Jerome Brunet 2024-02-23 18:51:07 +01:00 committed by Sasha Levin
parent e3adf12624
commit 8441012261

View file

@ -266,8 +266,8 @@ static int axg_tdm_iface_set_sclk(struct snd_soc_dai *dai,
srate = iface->slots * iface->slot_width * params_rate(params);
if (!iface->mclk_rate) {
/* If no specific mclk is requested, default to bit clock * 4 */
clk_set_rate(iface->mclk, 4 * srate);
/* If no specific mclk is requested, default to bit clock * 2 */
clk_set_rate(iface->mclk, 2 * srate);
} else {
/* Check if we can actually get the bit clock from mclk */
if (iface->mclk_rate % srate) {