ASoC: mmp-sspa: Set appropriate bus format for given bit width

The values set by set_dai_fmt() and hw_params() seem to be tailored only
for 32-bit formats. Negotiate the correct ones in hw_params() callback
instead.

This was essentially copied from the OLPC kernel driver and tested to
fix wrong audio output for non-32bit formats. The documentation is not
available.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Link: https://lore.kernel.org/r/20200511210134.1224532-10-lkundrak@v3.sk
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/pxa/mmp-sspa.c

@@ -191,8 +191,6 @@ static int mmp_sspa_set_dai_fmt(struct snd_soc_dai *cpu_dai,
 
 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 	case SND_SOC_DAIFMT_I2S:
-		sspa->sp |= SSPA_TXSP_FPER(63);
-		sspa->sp |= SSPA_SP_FWID(31);
 		sspa->ctrl |= SSPA_CTL_XDATDLY(1);
 		break;
 	default:
@@ -216,30 +214,48 @@ static int mmp_sspa_hw_params(struct snd_pcm_substream *substream,
 {
 	struct sspa_priv *sspa = snd_soc_dai_get_drvdata(dai);
 	u32 sspa_ctrl = sspa->ctrl;
-
-	sspa_ctrl &= ~SSPA_CTL_XFRLEN1_MASK;
-	sspa_ctrl |= SSPA_CTL_XFRLEN1(params_channels(params) - 1);
-	sspa_ctrl &= ~SSPA_CTL_XWDLEN1_MASK;
-	sspa_ctrl |= SSPA_CTL_XWDLEN1(SSPA_CTL_32_BITS);
-	sspa_ctrl &= ~SSPA_CTL_XSSZ1_MASK;
+	int bits;
+	int bitval;
 
 	switch (params_format(params)) {
 	case SNDRV_PCM_FORMAT_S8:
-		sspa_ctrl |= SSPA_CTL_XSSZ1(SSPA_CTL_8_BITS);
+		bits = 8;
+		bitval = SSPA_CTL_8_BITS;
 		break;
 	case SNDRV_PCM_FORMAT_S16_LE:
-		sspa_ctrl |= SSPA_CTL_XSSZ1(SSPA_CTL_16_BITS);
+		bits = 16;
+		bitval = SSPA_CTL_16_BITS;
 		break;
 	case SNDRV_PCM_FORMAT_S24_3LE:
-		sspa_ctrl |= SSPA_CTL_XSSZ1(SSPA_CTL_24_BITS);
+		bits = 24;
+		bitval = SSPA_CTL_24_BITS;
 		break;
 	case SNDRV_PCM_FORMAT_S32_LE:
-		sspa_ctrl |= SSPA_CTL_XSSZ1(SSPA_CTL_32_BITS);
+		bits = 32;
+		bitval = SSPA_CTL_32_BITS;
 		break;
 	default:
 		return -EINVAL;
 	}
 
+	if (params_channels(params) == 2)
+		sspa_ctrl |= SSPA_CTL_XPH;
+
+	sspa_ctrl &= ~SSPA_CTL_XWDLEN1_MASK;
+	sspa_ctrl |= SSPA_CTL_XWDLEN1(bitval);
+
+	sspa_ctrl &= ~SSPA_CTL_XSSZ1_MASK;
+	sspa_ctrl |= SSPA_CTL_XSSZ1(bitval);
+
+	sspa_ctrl &= ~SSPA_CTL_XSSZ2_MASK;
+	sspa_ctrl |= SSPA_CTL_XSSZ2(bitval);
+
+	sspa->sp &= ~SSPA_SP_FWID_MASK;
+	sspa->sp |= SSPA_SP_FWID(bits - 1);
+
+	sspa->sp &= ~SSPA_TXSP_FPER_MASK;
+	sspa->sp |= SSPA_TXSP_FPER(bits * 2 - 1);
+
 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 		mmp_sspa_write_reg(sspa, SSPA_TXCTL, sspa_ctrl);
 		mmp_sspa_write_reg(sspa, SSPA_TXFIFO_LL, 0x1);

sound/soc/pxa/mmp-sspa.h

@@ -63,7 +63,9 @@
 #define	SSPA_SP_FFLUSH		(1 << 2)	/* FIFO Flush */
 #define	SSPA_SP_S_RST		(1 << 1)	/* Active High Reset Signal */
 #define	SSPA_SP_S_EN		(1 << 0)	/* Serial Clock Domain Enable */
+#define	SSPA_SP_FWID_MASK	(0x3f << 20)
 #define	SSPA_SP_FWID(x)		((x) << 20)	/* Frame-Sync Width */
+#define	SSPA_TXSP_FPER_MASK	(0x3f << 4)
 #define	SSPA_TXSP_FPER(x)	((x) << 4)	/* Frame-Sync Active */
 
 /* sspa clock sources */