[PATCH 2/7] ASoC: spacemit: move hw constraints from hw_params to startup

[Troy Mitchell]

Hardware constraints should be applied in the startup callback rather
than hw_params, as hw_params may be called too late for the constraints
to take effect properly.

Move the channel count and format constraints for I2S and DSP_A/DSP_B
modes into a new startup callback. This also tightens the I2S mode
channel constraint from 1-2 to exactly 2, matching the actual hardware
behavior.

Signed-off-by: Troy Mitchell <troy.mitchell at linux.spacemit.com>
---
 sound/soc/spacemit/k1_i2s.c | 45 ++++++++++++++++++++++++++++++++-------------
 1 file changed, 32 insertions(+), 13 deletions(-)

diff --git a/sound/soc/spacemit/k1_i2s.c b/sound/soc/spacemit/k1_i2s.c
index 5c878f02cc93..e59624b2e23a 100644
--- a/sound/soc/spacemit/k1_i2s.c
+++ b/sound/soc/spacemit/k1_i2s.c
@@ -106,6 +106,37 @@ static void spacemit_i2s_init(struct spacemit_i2s_dev *i2s)
 	writel(0, i2s->base + SSINTEN);
 }
 
+static int spacemit_i2s_startup(struct snd_pcm_substream *substream,
+	struct snd_soc_dai *dai)
+{
+	struct spacemit_i2s_dev *i2s = snd_soc_dai_get_drvdata(dai);
+
+	switch (i2s->dai_fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
+	case SND_SOC_DAIFMT_I2S:
+		snd_pcm_hw_constraint_minmax(substream->runtime,
+					     SNDRV_PCM_HW_PARAM_CHANNELS,
+					     2, 2);
+		snd_pcm_hw_constraint_mask64(substream->runtime,
+					     SNDRV_PCM_HW_PARAM_FORMAT,
+					     SNDRV_PCM_FMTBIT_S16_LE);
+		break;
+	case SND_SOC_DAIFMT_DSP_A:
+	case SND_SOC_DAIFMT_DSP_B:
+		snd_pcm_hw_constraint_minmax(substream->runtime,
+					     SNDRV_PCM_HW_PARAM_CHANNELS,
+					     1, 1);
+		snd_pcm_hw_constraint_mask64(substream->runtime,
+					     SNDRV_PCM_HW_PARAM_FORMAT,
+					     SNDRV_PCM_FMTBIT_S32_LE);
+		break;
+	default:
+		dev_dbg(i2s->dev, "unexpected format type");
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
 static int spacemit_i2s_hw_params(struct snd_pcm_substream *substream,
 				  struct snd_pcm_hw_params *params,
 				  struct snd_soc_dai *dai)
@@ -153,22 +184,9 @@ static int spacemit_i2s_hw_params(struct snd_pcm_substream *substream,
 			dma_data->maxburst = 32;
 			dma_data->addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
 		}
-
-		snd_pcm_hw_constraint_minmax(substream->runtime,
-					     SNDRV_PCM_HW_PARAM_CHANNELS,
-					     1, 2);
-		snd_pcm_hw_constraint_mask64(substream->runtime,
-					     SNDRV_PCM_HW_PARAM_FORMAT,
-					     SNDRV_PCM_FMTBIT_S16_LE);
 		break;
 	case SND_SOC_DAIFMT_DSP_A:
 	case SND_SOC_DAIFMT_DSP_B:
-		snd_pcm_hw_constraint_minmax(substream->runtime,
-					     SNDRV_PCM_HW_PARAM_CHANNELS,
-					     1, 1);
-		snd_pcm_hw_constraint_mask64(substream->runtime,
-					     SNDRV_PCM_HW_PARAM_FORMAT,
-					     SNDRV_PCM_FMTBIT_S32_LE);
 		break;
 	default:
 		dev_dbg(i2s->dev, "unexpected format type");
@@ -303,6 +321,7 @@ static int spacemit_i2s_dai_remove(struct snd_soc_dai *dai)
 static const struct snd_soc_dai_ops spacemit_i2s_dai_ops = {
 	.probe = spacemit_i2s_dai_probe,
 	.remove = spacemit_i2s_dai_remove,
+	.startup = spacemit_i2s_startup,
 	.hw_params = spacemit_i2s_hw_params,
 	.set_sysclk = spacemit_i2s_set_sysclk,
 	.set_fmt = spacemit_i2s_set_fmt,

-- 
2.54.0