Hi Sugar Zhang,
Sorry to dig out this old thread, but I have two questions. Please see below:
On 9/3/21 15:23, Sugar Zhang wrote:
This patch adds support for rv1126 pdm controller which redesign cic filiter for better performance.
Signed-off-by: Sugar Zhang sugar.zhang@rock-chips.com
Changes in v4: None Changes in v3: None Changes in v2: None
sound/soc/rockchip/rockchip_pdm.c | 76 +++++++++++++++++++++++++++++++++++---- sound/soc/rockchip/rockchip_pdm.h | 3 ++ 2 files changed, 73 insertions(+), 6 deletions(-)
diff --git a/sound/soc/rockchip/rockchip_pdm.c b/sound/soc/rockchip/rockchip_pdm.c index 38bd603..67634d1 100644 --- a/sound/soc/rockchip/rockchip_pdm.c +++ b/sound/soc/rockchip/rockchip_pdm.c @@ -24,6 +24,7 @@ enum rk_pdm_version { RK_PDM_RK3229, RK_PDM_RK3308,
- RK_PDM_RV1126,
};
struct rk_pdm_dev { @@ -121,6 +122,55 @@ static unsigned int get_pdm_ds_ratio(unsigned int sr) return ratio; }
+static unsigned int get_pdm_cic_ratio(unsigned int clk) +{
- switch (clk) {
- case 4096000:
- case 5644800:
- case 6144000:
return 0;- case 2048000:
- case 2822400:
- case 3072000:
return 1;- case 1024000:
- case 1411200:
- case 1536000:
return 2;- default:
return 1;- }
+}
+static unsigned int samplerate_to_bit(unsigned int samplerate) +{
- switch (samplerate) {
- case 8000:
- case 11025:
- case 12000:
return 0;- case 16000:
- case 22050:
- case 24000:
return 1;- case 32000:
return 2;- case 44100:
- case 48000:
return 3;- case 64000:
- case 88200:
- case 96000:
return 4;- case 128000:
- case 176400:
- case 192000:
return 5;- default:
return 1;- }
+}
static inline struct rk_pdm_dev *to_info(struct snd_soc_dai *dai) { return snd_soc_dai_get_drvdata(dai); @@ -166,7 +216,8 @@ static int rockchip_pdm_hw_params(struct snd_pcm_substream *substream, if (ret) return -EINVAL;
- if (pdm->version == RK_PDM_RK3308) {
- if (pdm->version == RK_PDM_RK3308 ||
pdm->version == RK_PDM_RV1126) {@@ -194,8 +245,18 @@ static int rockchip_pdm_hw_params(struct snd_pcm_substream *substream, PDM_CLK_FD_RATIO_MSK, val); }
- val = get_pdm_ds_ratio(samplerate);
- regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_DS_RATIO_MSK, val);
- if (pdm->version == RK_PDM_RV1126) {
val = get_pdm_cic_ratio(clk_out);regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_CIC_RATIO_MSK, val);val = samplerate_to_bit(samplerate);regmap_update_bits(pdm->regmap, PDM_CTRL0,PDM_SAMPLERATE_MSK, PDM_SAMPLERATE(val));- } else {
val = get_pdm_ds_ratio(samplerate);regmap_update_bits(pdm->regmap, PDM_CLK_CTRL, PDM_DS_RATIO_MSK, val);- }
- regmap_update_bits(pdm->regmap, PDM_HPF_CTRL, PDM_HPF_CF_MSK, PDM_HPF_60HZ); regmap_update_bits(pdm->regmap, PDM_HPF_CTRL,
@@ -441,9 +502,10 @@ static bool rockchip_pdm_precious_reg(struct device *dev, unsigned int reg) }
static const struct reg_default rockchip_pdm_reg_defaults[] = {
- {0x04, 0x78000017},
- {0x08, 0x0bb8ea60},
- {0x18, 0x0000001f},
- { PDM_CTRL0, 0x78000017 },
- { PDM_CTRL1, 0x0bb8ea60 },
- { PDM_CLK_CTRL, 0x0000e401 },
- { PDM_DMA_CTRL, 0x0000001f },
};
static const struct regmap_config rockchip_pdm_regmap_config = { @@ -469,6 +531,8 @@ static const struct of_device_id rockchip_pdm_match[] __maybe_unused = { .data = (void *)RK_PDM_RK3308 }, { .compatible = "rockchip,rk3308-pdm", .data = (void *)RK_PDM_RK3308 },
- { .compatible = "rockchip,rv1126-pdm",
.data = (void *)RK_PDM_RV1126 },}; MODULE_DEVICE_TABLE(of, rockchip_pdm_match); diff --git a/sound/soc/rockchip/rockchip_pdm.h b/sound/soc/rockchip/rockchip_pdm.h index 8e5bbaf..13bfbc2 100644 --- a/sound/soc/rockchip/rockchip_pdm.h +++ b/sound/soc/rockchip/rockchip_pdm.h @@ -41,6 +41,8 @@ #define PDM_PATH1_EN BIT(28) #define PDM_PATH0_EN BIT(27) #define PDM_HWT_EN BIT(26) +#define PDM_SAMPLERATE_MSK GENMASK(7, 5) +#define PDM_SAMPLERATE(x) ((x) << 5) #define PDM_VDW_MSK (0x1f << 0) #define PDM_VDW(X) ((X - 1) << 0)
The TRM of RV1126 and RK3568 both state that sample resolutions from 16 up to 24 bits are supported. However, I don't see anything in this patch that restricts the capture formats accordingly. In fact, the driver offers SNDRV_PCM_FMTBIT_S32_LE in my setup and via this PDM_VDW macro 31 is written to PDM_CTRL0, which is undefined behavior according to the TRM.
Are 32 bit samples supported by the RK3568/RV1126 PDM block?
@@ -66,6 +68,7 @@ #define PDM_CLK_1280FS (0x2 << 0) #define PDM_CLK_2560FS (0x3 << 0) #define PDM_CLK_5120FS (0x4 << 0) +#define PDM_CIC_RATIO_MSK (0x3 << 0)
/* PDM HPF CTRL */ #define PDM_HPF_LE BIT(3)
Also, I noticed that the number of channels must be an even number. Shouldn't it be possible to use a single mono PDM microphone with this PDM block (i.e., having one channel)?
Thanks a lot and best regards, Michael