Sorry, I couldn't resist adding three more comments to improve further:
-static int skylake_nau8825_hw_params(struct snd_pcm_substream *substream,
- struct snd_pcm_hw_params *params)
+static int skylake_nau8825_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct snd_soc_pcm_runtime *rtd = substream->private_data;
+ struct snd_pcm_runtime *runtime = substream->runtime;
struct snd_soc_dai *codec_dai = asoc_rtd_to_codec(rtd, 0);
- int ret;
-
- ret = snd_soc_dai_set_sysclk(codec_dai,
- NAU8825_CLK_MCLK, 24000000, SND_SOC_CLOCK_IN);
+ int ret = 0;
- if (ret < 0)
- dev_err(rtd->dev, "snd_soc_dai_set_sysclk err = %d\n", ret);
+ switch (cmd) {
+ case SNDRV_PCM_TRIGGER_START:
+ ret = snd_soc_dai_set_sysclk(codec_dai, NAU8825_CLK_FLL_FS, 0,
+ SND_SOC_CLOCK_IN);
Maybe a simple comment to explain what this does?
+ if (ret < 0) {
+ dev_err(codec_dai->dev, "can't set FS clock %d\n", ret);
+ break;
+ }
+ ret = snd_soc_dai_set_pll(codec_dai, 0, 0, runtime->rate,
+ runtime->rate * 256);
+ if (ret < 0)
+ dev_err(codec_dai->dev, "can't set FLL: %d\n", ret);
+ break;
You could replace this by a /* fallthrough */ statement?
+ case SNDRV_PCM_TRIGGER_RESUME:
+ ret = snd_soc_dai_set_pll(codec_dai, 0, 0, runtime->rate,
+ runtime->rate * 256);
+ if (ret < 0)
+ dev_err(codec_dai->dev, "can't set FLL: %d\n", ret);
+ break;
+ }
+static int __maybe_unused skylake_nau8825_resume_post(struct snd_soc_card *card)
+{
+ struct snd_soc_dai *codec_dai;
+
+ codec_dai = snd_soc_card_get_codec_dai(card, SKL_NUVOTON_CODEC_DAI);
+ if (!codec_dai) {
+ dev_err(card->dev, "Codec dai not found\n");
+ return -EIO;
+ }
+
+ dev_dbg(codec_dai->dev, "playback_active:%d playback_widget->active:%d codec_dai->rate:%d\n",
+ codec_dai->stream_active[SNDRV_PCM_STREAM_PLAYBACK],
+ codec_dai->playback_widget->active,
+ codec_dai->rate);
+
+ if (codec_dai->stream_active[SNDRV_PCM_STREAM_PLAYBACK] &&
+ codec_dai->playback_widget->active)
+ snd_soc_dai_set_sysclk(codec_dai, NAU8825_CLK_FLL_FS, 0,
+ SND_SOC_CLOCK_IN);
And that part is also worthy of a comment, e.g. why not do this as part
of the TRIGGER_RESUME and why only for playback?
--- a/sound/soc/intel/boards/skl_nau88l25_ssm4567.c
+++ b/sound/soc/intel/boards/skl_nau88l25_ssm4567.c
same comments for this other machine driver.
