@@ -90,6 +90,15 @@
#define MCHP_PDMC_DS_NO 2
#define MCHP_PDMC_EDGE_NO 2
+/*
+ * ---- DMA chunk size allowed ----
+ */
+#define MCHP_PDMC_DMA_8_WORD_CHUNK 8
+#define MCHP_PDMC_DMA_4_WORD_CHUNK 4
+#define MCHP_PDMC_DMA_2_WORD_CHUNK 2
+#define MCHP_PDMC_DMA_1_WORD_CHUNK 1
+#define DMA_BURST_ALIGNED(_p, _s, _w) !(_p % (_s * _w))
+
struct mic_map {
int ds_pos;
int clk_edge;
@@ -511,15 +520,18 @@ static u32 mchp_pdmc_mr_set_osr(int audio_filter_en, unsigned int osr)
return 0;
}
-static inline int mchp_pdmc_period_to_maxburst(int period_size)
+static inline int mchp_pdmc_period_to_maxburst(int period_size, int sample_size)
{
- if (!(period_size % 8))
- return 8;
- if (!(period_size % 4))
- return 4;
- if (!(period_size % 2))
- return 2;
- return 1;
+ int p_size = period_size;
+ int s_size = sample_size;
+
+ if (DMA_BURST_ALIGNED(p_size, s_size, MCHP_PDMC_DMA_8_WORD_CHUNK))
+ return MCHP_PDMC_DMA_8_WORD_CHUNK;
+ if (DMA_BURST_ALIGNED(p_size, s_size, MCHP_PDMC_DMA_4_WORD_CHUNK))
+ return MCHP_PDMC_DMA_4_WORD_CHUNK;
+ if (DMA_BURST_ALIGNED(p_size, s_size, MCHP_PDMC_DMA_2_WORD_CHUNK))
+ return MCHP_PDMC_DMA_2_WORD_CHUNK;
+ return MCHP_PDMC_DMA_1_WORD_CHUNK;
}
static struct snd_pcm_chmap_elem mchp_pdmc_std_chmaps[] = {
@@ -547,14 +559,18 @@ static int mchp_pdmc_hw_params(struct snd_pcm_substream *substream,
unsigned int channels = params_channels(params);
unsigned int osr = 0, osr_start;
unsigned int fs = params_rate(params);
+ int sample_bytes = params_physical_width(params) / 8;
+ int period_bytes = params_period_size(params) *
+ params_channels(params) * sample_bytes;
+ int maxburst;
u32 mr_val = 0;
u32 cfgr_val = 0;
int i;
int ret;
- dev_dbg(comp->dev, "%s() rate=%u format=%#x width=%u channels=%u\n",
+ dev_dbg(comp->dev, "%s() rate=%u format=%#x width=%u channels=%u period_bytes=%d\n",
__func__, params_rate(params), params_format(params),
- params_width(params), params_channels(params));
+ params_width(params), params_channels(params), period_bytes);
if (channels > dd->mic_no) {
dev_err(comp->dev, "more channels %u than microphones %d\n",
@@ -608,7 +624,8 @@ static int mchp_pdmc_hw_params(struct snd_pcm_substream *substream,
mr_val |= FIELD_PREP(MCHP_PDMC_MR_SINCORDER_MASK, dd->sinc_order);
- dd->addr.maxburst = mchp_pdmc_period_to_maxburst(snd_pcm_lib_period_bytes(substream));
+ maxburst = mchp_pdmc_period_to_maxburst(period_bytes, sample_bytes);
+ dd->addr.maxburst = maxburst;
mr_val |= FIELD_PREP(MCHP_PDMC_MR_CHUNK_MASK, dd->addr.maxburst);
dev_dbg(comp->dev, "maxburst set to %d\n", dd->addr.maxburst);