Support ALSA IEC958 plugin for KeemBay I2S driver.
Bit manipulation needed as IEC958 format supported by ADV7511 HDMI chip
is not compatible with the ALSA IEC958 plugin format.
Signed-off-by: Sia Jee Heng <jee.heng.sia@xxxxxxxxx>
---
sound/soc/intel/keembay/kmb_platform.c | 73 +++++++++++++++++++++++++-
sound/soc/intel/keembay/kmb_platform.h | 1 +
2 files changed, 73 insertions(+), 1 deletion(-)
diff --git a/sound/soc/intel/keembay/kmb_platform.c b/sound/soc/intel/keembay/kmb_platform.c
index 4961ba89c110..0fd1e8f62c89 100644
--- a/sound/soc/intel/keembay/kmb_platform.c
+++ b/sound/soc/intel/keembay/kmb_platform.c
@@ -5,6 +5,7 @@
// Intel KeemBay Platform driver.
//
+#include <linux/bitrev.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/io.h>
@@ -39,7 +40,8 @@ static const struct snd_pcm_hardware kmb_pcm_hardware = {
.rate_max = 48000,
.formats = SNDRV_PCM_FMTBIT_S16_LE |
SNDRV_PCM_FMTBIT_S24_LE |
- SNDRV_PCM_FMTBIT_S32_LE,
+ SNDRV_PCM_FMTBIT_S32_LE |
+ SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE,
.channels_min = 2,
.channels_max = 2,
.buffer_bytes_max = BUFFER_BYTES_MAX,
@@ -50,6 +52,50 @@ static const struct snd_pcm_hardware kmb_pcm_hardware = {
.fifo_size = 16,
};
+/*
+ * Convert to ADV7511 HDMI hardware format.
+ * ADV7511 HDMI chip need parity bit replaced by block start bit and
+ * with the preamble bits left out.
+ * ALSA IEC958 subframe format:
+ * bit 0-3 = preamble (0x8 = block start)
+ * 4-7 = AUX (=0)
+ * 8-27 = audio data (without AUX if 24bit sample)
+ * 28 = validity
+ * 29 = user data
+ * 30 = channel status
+ * 31 = parity
+ *
+ * ADV7511 IEC958 subframe format:
+ * bit 0-23 = audio data
+ * 24 = validity
+ * 25 = user data
+ * 26 = channel status
+ * 27 = block start
+ * 28-31 = 0
+ * MSB to LSB bit reverse by software as hardware not supporting it.
+ */
+static void hdmi_reformat_iec958(struct snd_pcm_runtime *runtime,
+ struct kmb_i2s_info *kmb_i2s,
+ unsigned int tx_ptr)
+{
+ u32(*buf)[2] = (void *)runtime->dma_area;
+ unsigned long temp;
+ u32 i, j, sample;
+
+ for (i = 0; i < kmb_i2s->fifo_th; i++) {
+ j = 0;
+ do {
+ temp = buf[tx_ptr][j];
+ /* Replace parity with block start*/
+ assign_bit(31, &temp, (BIT(3) & temp));
+ sample = bitrev32(temp);
+ buf[tx_ptr][j] = sample << 4;
+ j++;
+ } while (j < 2);
+ tx_ptr++;
+ }
+}
+
static unsigned int kmb_pcm_tx_fn(struct kmb_i2s_info *kmb_i2s,
struct snd_pcm_runtime *runtime,
unsigned int tx_ptr, bool *period_elapsed)
@@ -65,6 +111,8 @@ static unsigned int kmb_pcm_tx_fn(struct kmb_i2s_info *kmb_i2s,
writel(((u16(*)[2])buf)[tx_ptr][0], i2s_base + LRBR_LTHR(0));
writel(((u16(*)[2])buf)[tx_ptr][1], i2s_base + RRBR_RTHR(0));
} else {
+ if (kmb_i2s->iec958_fmt)
+ hdmi_reformat_iec958(runtime, kmb_i2s, tx_ptr);
writel(((u32(*)[2])buf)[tx_ptr][0], i2s_base + LRBR_LTHR(0));
writel(((u32(*)[2])buf)[tx_ptr][1], i2s_base + RRBR_RTHR(0));
}
@@ -235,6 +283,7 @@ static int kmb_pcm_trigger(struct snd_soc_component *component,
kmb_i2s->tx_substream = NULL;
else
kmb_i2s->rx_substream = NULL;
+ kmb_i2s->iec958_fmt = false;
break;
default:
return -EINVAL;
@@ -549,6 +598,9 @@ static int kmb_dai_hw_params(struct snd_pcm_substream *substream,
kmb_i2s->play_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
kmb_i2s->capture_dma_data.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
break;
+ case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
+ kmb_i2s->iec958_fmt = true;
+ fallthrough;
case SNDRV_PCM_FORMAT_S32_LE:
config->data_width = 32;
kmb_i2s->ccr = 0x10;
@@ -686,6 +738,24 @@ static struct snd_soc_dai_ops kmb_dai_ops = {
.set_fmt = kmb_set_dai_fmt,
};
+static struct snd_soc_dai_driver intel_kmb_hdmi_dai[] = {
+ {
+ .name = "intel_kmb_hdmi_i2s",
+ .playback = {
+ .channels_min = 2,
+ .channels_max = 2,
+ .rates = SNDRV_PCM_RATE_48000,
+ .rate_min = 48000,
+ .rate_max = 48000,
+ .formats = (SNDRV_PCM_FMTBIT_S16_LE |
+ SNDRV_PCM_FMTBIT_S24_LE |
+ SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE),
+ },
+ .ops = &kmb_dai_ops,
+ .probe = kmb_probe,
+ },
+};
+
static struct snd_soc_dai_driver intel_kmb_i2s_dai[] = {
{
.name = "intel_kmb_i2s",
@@ -740,6 +810,7 @@ static struct snd_soc_dai_driver intel_kmb_tdm_dai[] = {
static const struct of_device_id kmb_plat_of_match[] = {
{ .compatible = "intel,keembay-i2s", .data = &intel_kmb_i2s_dai},
+ { .compatible = "intel,keembay-hdmi-i2s", .data = &intel_kmb_hdmi_dai},
{ .compatible = "intel,keembay-tdm", .data = &intel_kmb_tdm_dai},
{}
};
diff --git a/sound/soc/intel/keembay/kmb_platform.h b/sound/soc/intel/keembay/kmb_platform.h
index 67234caee814..29be2cd84ddb 100644
--- a/sound/soc/intel/keembay/kmb_platform.h
+++ b/sound/soc/intel/keembay/kmb_platform.h
@@ -150,6 +150,7 @@ struct kmb_i2s_info {
struct snd_pcm_substream *rx_substream;
unsigned int tx_ptr;
unsigned int rx_ptr;
+ bool iec958_fmt;
};
#endif /* KMB_PLATFORM_H_ */
--
2.18.0
