Re: [PATCH v2 3/3] ASoC: tlv320adcx140: Add proper support for master mode

From: Dan Murphy
Date: Tue Sep 15 2020 - 14:52:47 EST


Camel

On 9/11/20 3:07 AM, Camel Guo wrote:
From: Camel Guo <camelg@xxxxxxxx>

Add setup of bclk-to-ws ratio and sample rate when in master mode,
as well as MCLK input pin setup.

Signed-off-by: Camel Guo <camelg@xxxxxxxx>
---
v2:
- Move GPIO setting into devicetree
- Move master config register setting into a new function

sound/soc/codecs/tlv320adcx140.c | 139 ++++++++++++++++++++++++++++++-
sound/soc/codecs/tlv320adcx140.h | 27 ++++++
2 files changed, 162 insertions(+), 4 deletions(-)

diff --git a/sound/soc/codecs/tlv320adcx140.c b/sound/soc/codecs/tlv320adcx140.c
index 97f16fbba441..685f5fd8b537 100644
--- a/sound/soc/codecs/tlv320adcx140.c
+++ b/sound/soc/codecs/tlv320adcx140.c
@@ -35,6 +35,7 @@ struct adcx140_priv {
unsigned int dai_fmt;
unsigned int tdm_delay;
unsigned int slot_width;
+ bool master;
};
static const char * const gpo_config_names[] = {
@@ -651,11 +652,136 @@ static int adcx140_reset(struct adcx140_priv *adcx140)
return ret;
}
+static int adcx140_fs_bclk_ratio(unsigned int bclk_ratio)
+{
+ switch (bclk_ratio) {
+ case 16:
+ return ADCX140_RATIO_16;
+ case 24:
+ return ADCX140_RATIO_24;
+ case 32:
+ return ADCX140_RATIO_32;
+ case 48:
+ return ADCX140_RATIO_48;
+ case 64:
+ return ADCX140_RATIO_64;
+ case 96:
+ return ADCX140_RATIO_96;
+ case 128:
+ return ADCX140_RATIO_128;
+ case 192:
+ return ADCX140_RATIO_192;
+ case 256:
+ return ADCX140_RATIO_256;
+ case 384:
+ return ADCX140_RATIO_384;
+ case 512:
+ return ADCX140_RATIO_512;
+ case 1024:
+ return ADCX140_RATIO_1024;
+ case 2048:
+ return ADCX140_RATIO_2048;
+ default:
+ break;
+ }
+ return -EINVAL;
+}
+
+static int adcx140_fs_rate(unsigned int rate)
+{
+ switch (rate) {
+ case 7350:
+ case 8000:
+ return ADCX140_8_OR_7_35KHZ;
+ case 14700:
+ case 16000:
+ return ADCX140_16_OR_14_7KHZ;
+ case 22050:
+ case 24000:
+ return ADCX140_24_OR_22_05KHZ;
+ case 29400:
+ case 32000:
+ return ADCX140_32_OR_29_4KHZ;
+ case 44100:
+ case 48000:
+ return ADCX140_48_OR_44_1KHZ;
+ case 88200:
+ case 96000:
+ return ADCX140_96_OR_88_2KHZ;
+ case 176400:
+ case 192000:
+ return ADCX140_192_OR_176_4KHZ;
+ case 352800:
+ case 384000:
+ return ADCX140_384_OR_352_8KHZ;
+ case 705600:
+ case 768000:
+ return ADCX140_768_OR_705_6KHZ;
+ default:
+ break;
+ }
+ return -EINVAL;
+}
+
+static int adcx140_setup_master_config(struct snd_soc_component *component,
+ struct snd_pcm_hw_params *params)
+{
+ int ret = 0;
+ struct adcx140_priv *adcx140 = snd_soc_component_get_drvdata(component);
+
+ if (adcx140->master) {

Move this out to hw_params.  No reason to jump here just to jump back.

Check for master and if master then configure

This will eliminate the mixed code and variable declaration below which is what I wanted to avoid in v1.

This will also allow you to remove some of the variable initialization.

+ u8 mst_cfg1 = 0;
+ u8 mst_cfg0 = 0;
This can be init to mst_cfg0 = ADCX140_BCLK_FSYNC_MASTER no reason to set it here and then change it immediately.
+ unsigned int bclk_ratio;
+
+ mst_cfg0 = ADCX140_BCLK_FSYNC_MASTER;
+ if (params_rate(params) % 1000)
+ mst_cfg0 |= ADCX140_FSYNCINV_BIT; /* 44.1 kHz et al */
+
+ ret = adcx140_fs_rate(params_rate(params));
+ if (ret < 0) {
+ dev_err(adcx140->dev, "%s: Unsupported rate %d\n",
+ __func__, params_rate(params));
+ return ret;
+ }
+ mst_cfg1 |= ret;
Why the | here?  This is initialized to 0 so mst_cfg1 = ret. And why even use ret just return into mst_cfg1 and check that variable
+
+ /* In slave mode when using automatic clock configuration,
+ * the codec figures out the BCLK to FSYNC ratio itself. But
+ * here in master mode, we need to tell it.
+ */
+
+ bclk_ratio = snd_soc_params_to_frame_size(params);
+ ret = adcx140_fs_bclk_ratio(bclk_ratio);
+ if (ret < 0) {
+ dev_err(adcx140->dev, "%s: Unsupported bclk_ratio %d\n",
+ __func__, bclk_ratio);
+ return ret;
+ }
+ mst_cfg1 |= ret;
+
+ snd_soc_component_update_bits(component, ADCX140_MST_CFG1,
+ ADCX140_FS_RATE_MSK |
+ ADCX140_RATIO_MSK,
+ mst_cfg1);

I don't understand the update_bits since you have calcualted both the Ratio and rate you can just write the register with the snd_soc_component_write.

+
+ snd_soc_component_update_bits(component, ADCX140_MST_CFG0,
+ ADCX140_FSYNCINV_BIT |
+ ADCX140_BCLK_FSYNC_MASTER,
+ mst_cfg0);
+

But this is ok.  I actually have other changes I am posting which move this to the set_dai_format.  So I am not sure if this will be needed after that patch is applied.

I will CC you on those patches.

Dan