[alsa-devel] [PATCH] ASoC: nau8822: support master mode

[John Hsu]

From: David Lin <CTLIN0 at nuvoton.com>

The driver selects the proper BCLK divide through the BCLK and FS
at the hardware parameter when the I2S master mode.

Signed-off-by: David Lin <CTLIN0 at nuvoton.com>
Signed-off-by: John Hsu <KCHSU0 at nuvoton.com>
---
 sound/soc/codecs/nau8822.c | 18 ++++++++++++++++++
 sound/soc/codecs/nau8822.h |  7 +++++++
 2 files changed, 25 insertions(+)

diff --git a/sound/soc/codecs/nau8822.c b/sound/soc/codecs/nau8822.c
index c6152a044416..78db3bd0b3bc 100644
--- a/sound/soc/codecs/nau8822.c
+++ b/sound/soc/codecs/nau8822.c
@@ -828,6 +828,24 @@ static int nau8822_hw_params(struct snd_pcm_substream *substream,
 	struct snd_soc_component *component = dai->component;
 	struct nau8822 *nau8822 = snd_soc_component_get_drvdata(component);
 	int val_len = 0, val_rate = 0;
+	unsigned int ctrl_val, bclk_fs, bclk_div;
+
+	/* make BCLK and LRC divide configuration if the codec as master. */
+	snd_soc_component_read(component, NAU8822_REG_CLOCKING, &ctrl_val);
+	if (ctrl_val & NAU8822_CLK_MASTER) {
+		/* get the bclk and fs ratio */
+		bclk_fs = snd_soc_params_to_bclk(params) / params_rate(params);
+		if (bclk_fs <= 32)
+			bclk_div = NAU8822_BCLKDIV_8;
+		else if (bclk_fs <= 64)
+			bclk_div = NAU8822_BCLKDIV_4;
+		else if (bclk_fs <= 128)
+			bclk_div = NAU8822_BCLKDIV_2;
+		else
+			return -EINVAL;
+		snd_soc_component_update_bits(component, NAU8822_REG_CLOCKING,
+				NAU8822_BCLKSEL_MASK, bclk_div);
+	}
 
 	switch (params_format(params)) {
 	case SNDRV_PCM_FORMAT_S16_LE:
diff --git a/sound/soc/codecs/nau8822.h b/sound/soc/codecs/nau8822.h
index 9c552983a293..489191ff187e 100644
--- a/sound/soc/codecs/nau8822.h
+++ b/sound/soc/codecs/nau8822.h
@@ -107,10 +107,17 @@
 
 /* NAU8822_REG_CLOCKING (0x6) */
 #define NAU8822_CLKIOEN_MASK			0x1
+#define NAU8822_CLK_MASTER			0x1
+#define NAU8822_CLK_SLAVE			0x0
 #define NAU8822_MCLKSEL_SFT			5
 #define NAU8822_MCLKSEL_MASK			(0x7 << 5)
 #define NAU8822_BCLKSEL_SFT			2
 #define NAU8822_BCLKSEL_MASK			(0x7 << 2)
+#define NAU8822_BCLKDIV_1			(0x0 << 2)
+#define NAU8822_BCLKDIV_2			(0x1 << 2)
+#define NAU8822_BCLKDIV_4			(0x2 << 2)
+#define NAU8822_BCLKDIV_8			(0x3 << 2)
+#define NAU8822_BCLKDIV_16			(0x4 << 2)
 #define NAU8822_CLKM_MASK			(0x1 << 8)
 #define NAU8822_CLKM_MCLK			(0x0 << 8)
 #define NAU8822_CLKM_PLL			(0x1 << 8)
-- 
2.18.0