Re: [PATCH 4/6] ASoC: samsung: fsd: Add FSD soundcard driver

Krzysztof Kozlowski
2022-10-16T15:18:17Z

On 14/10/2022 06:21, Padmanabhan Rajanbabu wrote:
> Add a soundcard driver for FSD audio interface to bridge the
> CPU DAI of samsung I2S with the codec and platform driver.
>

Thank you for your patch. There is something to discuss/improve.

> +
> +#define FSD_PREFIX "tesla,"
> +#define FSD_DAI_SRC_PCLK 3
> +#define FSD_DAI_RFS_192 192
> +#define FSD_DAI_BFS_48 48
> +#define FSD_DAI_BFS_96 96
> +#define FSD_DAI_BFS_192 192
> +
> +struct fsd_card_priv {
> + struct snd_soc_card card;
> + struct snd_soc_dai_link *dai_link;
> + u32 tdm_slots;
> + u32 tdm_slot_width;
> +};
> +
> +static unsigned int fsd_card_get_rfs(unsigned int rate)
> +{
> + return FSD_DAI_RFS_192;

This wrapper is a bit silly...

> +}
> +
> +static unsigned int fsd_card_get_bfs(unsigned int channels)
> +{
> + switch (channels) {
> + case 1:
> + case 2:
> + return FSD_DAI_BFS_48;
> + case 3:
> + case 4:
> + return FSD_DAI_BFS_96;
> + case 5:
> + case 6:
> + case 7:
> + case 8:
> + return FSD_DAI_BFS_192;
> + default:
> + return FSD_DAI_BFS_48;
> + }
> +}
> +
> +static unsigned int fsd_card_get_psr(unsigned int rate)
> +{
> + switch (rate) {
> + case 8000: return 43;
> + case 11025: return 31;
> + case 16000: return 21;
> + case 22050: return 16;
> + case 32000: return 11;
> + case 44100: return 8;
> + case 48000: return 7;
> + case 64000: return 5;
> + case 88200: return 4;
> + case 96000: return 4;
> + case 192000: return 2;
> + default: return 1;
> + }
> +}
> +
> +static int fsd_card_hw_params(struct snd_pcm_substream *substream,
> + struct snd_pcm_hw_params *params)
> +{
> + struct snd_soc_pcm_runtime *rtd = substream->private_data;
> + struct snd_soc_card *card = rtd->card;
> + struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
> + struct snd_soc_dai_link *link = rtd->dai_link;
> + struct fsd_card_priv *priv = snd_soc_card_get_drvdata(card);
> + unsigned int rfs, bfs, psr;
> + int ret = 0, cdclk_dir;
> +
> + rfs = fsd_card_get_rfs(params_rate(params));
> + bfs = fsd_card_get_bfs(params_channels(params));
> + psr = fsd_card_get_psr(params_rate(params));
> +
> + /* Configure the Root Clock Source */
> + ret = snd_soc_dai_set_sysclk(cpu_dai, SAMSUNG_I2S_OPCLK,
> + false, FSD_DAI_SRC_PCLK);
> + if (ret < 0) {
> + dev_err(card->dev, "Failed to set OPCLK: %d\n", ret);
> + goto err;
> + }
> +
> + ret = snd_soc_dai_set_sysclk(cpu_dai, SAMSUNG_I2S_RCLKSRC_0,
> + false, false);
> + if (ret < 0) {
> + dev_err(card->dev, "Failed to set RCLKSRC: %d\n", ret);

Don't you need to cleanup on error paths?

> + goto err;
> + }
> +
> + /* Set CPU DAI configuration */
> + ret = snd_soc_dai_set_fmt(cpu_dai, link->dai_fmt);
> + if (ret < 0) {
> + dev_err(card->dev, "Failed to set DAIFMT: %d\n", ret);
> + goto err;
> + }
> +
> + if (link->dai_fmt & SND_SOC_DAIFMT_CBC_CFC) {
> + cdclk_dir = SND_SOC_CLOCK_OUT;
> + } else if (link->dai_fmt & SND_SOC_DAIFMT_CBP_CFP) {
> + cdclk_dir = SND_SOC_CLOCK_IN;
> + } else {
> + dev_err(card->dev, "Missing Clock Master information\n");
> + goto err;
> + }
> +
> + /* Set Clock Source for CDCLK */
> + ret = snd_soc_dai_set_sysclk(cpu_dai, SAMSUNG_I2S_CDCLK,
> + rfs, cdclk_dir);
> + if (ret < 0) {
> + dev_err(card->dev, "Failed to set CDCLK: %d\n", ret);
> + goto err;
> + }
> +
> + ret = snd_soc_dai_set_clkdiv(cpu_dai, SAMSUNG_I2S_DIV_RCLK, psr);
> + if (ret < 0) {
> + dev_err(card->dev, "Failed to set PSR: %d\n", ret);
> + goto err;
> + }
> +
> + ret = snd_soc_dai_set_clkdiv(cpu_dai, SAMSUNG_I2S_DIV_BCLK, bfs);
> + if (ret < 0) {
> + dev_err(card->dev, "Failed to set BCLK: %d\n", ret);
> + goto err;
> + }
> +
> + if (priv->tdm_slots) {
> + ret = snd_soc_dai_set_tdm_slot(cpu_dai, false, false,
> + priv->tdm_slots, priv->tdm_slot_width);
> + if (ret < 0) {
> + dev_err(card->dev,
> + "Failed to configure in TDM mode:%d\n", ret);
> + goto err;
> + }
> + }
> +
> +err:
> + return ret;
> +}
> +
> +static const struct snd_soc_ops fsd_card_ops = {
> + .hw_params = fsd_card_hw_params,
> +};
> +
> +static struct fsd_card_priv *fsd_card_parse_of(struct snd_soc_card *card)
> +{
> + struct fsd_card_priv *priv;
> + struct snd_soc_dai_link *link;
> + struct device *dev = card->dev;
> + struct device_node *node = dev->of_node;
> + struct device_node *np, *cpu_node, *codec_node;
> + struct snd_soc_dai_link_component *dlc;
> + int ret, id = 0, num_links;
> +
> + ret = snd_soc_of_parse_card_name(card, "model");
> + if (ret) {
> + dev_err(dev, "Error parsing card name: %d\n", ret);
> + return ERR_PTR(ret);

return dev_err_probe

> + }
> +
> + if (of_property_read_bool(dev->of_node, "widgets")) {
> + ret = snd_soc_of_parse_audio_simple_widgets(card, "widgets");
> + if (ret)
> + return ERR_PTR(ret);
> + }
> +
> + /* Add DAPM routes to the card */
> + if (of_property_read_bool(node, "audio-routing")) {
> + ret = snd_soc_of_parse_audio_routing(card, "audio-routing");
> + if (ret)
> + return ERR_PTR(ret);
> + }
> +
> + num_links = of_get_child_count(node);
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return ERR_PTR(-ENOMEM);
> +
> + priv->dai_link = devm_kzalloc(dev, num_links * sizeof(*priv->dai_link),
> + GFP_KERNEL);
> + if (!priv->dai_link)
> + return ERR_PTR(-ENOMEM);
> +
> + priv->tdm_slots = 0;
> + priv->tdm_slot_width = 0;
> +
> + snd_soc_of_parse_tdm_slot(node, NULL, NULL, &priv->tdm_slots,
> + &priv->tdm_slot_width);
> +
> + link = priv->dai_link;
> +
> + for_each_child_of_node(node, np) {
> + dlc = devm_kzalloc(dev, 2 * sizeof(*dlc), GFP_KERNEL);
> + if (!dlc)
> + return ERR_PTR(-ENOMEM);
> +
> + link->id = id;
> + link->cpus = &dlc[0];
> + link->platforms = &dlc[1];
> + link->num_cpus = 1;
> + link->num_codecs = 1;
> + link->num_platforms = 1;
> +
> + cpu_node = of_get_child_by_name(np, "cpu");
> + if (!cpu_node) {
> + dev_err(dev, "Missing CPU/Codec node\n");
> + ret = -EINVAL;
> + goto err_cpu_node;
> + }
> +
> + ret = snd_soc_of_get_dai_link_cpus(dev, cpu_node, link);
> + if (ret < 0) {
> + dev_err(dev, "Error Parsing CPU DAI name\n");
> + goto err_cpu_name;
> + }
> +
> + link->platforms->of_node = link->cpus->of_node;
> +
> + codec_node = of_get_child_by_name(np, "codec");
> + if (codec_node) {
> + ret = snd_soc_of_get_dai_link_codecs(dev, codec_node,
> + link);
> + if (ret < 0) {
> + dev_err(dev, "Error Parsing Codec DAI name\n");
> + goto err_codec_name;
> + }
> + } else {
> + dlc = devm_kzalloc(dev, sizeof(*dlc), GFP_KERNEL);
> + if (!dlc) {
> + ret = -ENOMEM;
> + goto err_cpu_name;
> + }
> +
> + link->codecs = dlc;
> +
> + link->codecs->dai_name = "snd-soc-dummy-dai";
> + link->codecs->name = "snd-soc-dummy";
> + link->dynamic = 1;
> +
> + snd_soc_dai_link_set_capabilities(link);
> + link->ignore_suspend = 1;
> + link->nonatomic = 1;
> + }
> +
> + ret = asoc_simple_parse_daifmt(dev, np, codec_node,
> + FSD_PREFIX, &link->dai_fmt);
> + if (ret)
> + link->dai_fmt = SND_SOC_DAIFMT_NB_NF |
> + SND_SOC_DAIFMT_CBC_CFC |
> + SND_SOC_DAIFMT_I2S;
> +
> + ret = of_property_read_string(np, "link-name", &link->name);
> + if (ret) {
> + dev_err(card->dev, "Error Parsing link name\n");
> + goto err_codec_name;
> + }
> +
> + link->stream_name = link->name;
> + link->ops = &fsd_card_ops;
> +
> + link++;
> + id++;
> +
> + of_node_put(cpu_node);
> + of_node_put(codec_node);
> + }
> +
> + card->dai_link = priv->dai_link;
> + card->num_links = num_links;
> +
> + return priv;
> +
> +err_codec_name:
> + of_node_put(codec_node);
> +err_cpu_name:
> + of_node_put(cpu_node);
> +err_cpu_node:
> + of_node_put(np);
> + return ERR_PTR(ret);
> +}
> +
> +static int fsd_platform_probe(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct snd_soc_card *card;
> + struct fsd_card_priv *fsd_priv;
> +
> + card = devm_kzalloc(dev, sizeof(*card), GFP_KERNEL);
> + if (!card)
> + return -ENOMEM;
> +
> + card->dev = dev;
> + fsd_priv = fsd_card_parse_of(card);

Drop the indentation before =

> +
> + if (IS_ERR(fsd_priv)) {
> + dev_err(&pdev->dev, "Error Parsing DAI Link: %ld\n",
> + PTR_ERR(fsd_priv));
> + return PTR_ERR(fsd_priv);

return dev_err_probe

> + }
> +
> + snd_soc_card_set_drvdata(card, fsd_priv);
> +
> + return devm_snd_soc_register_card(&pdev->dev, card);
> +}
> +
> +static const struct of_device_id fsd_device_id[] = {
> + { .compatible = "tesla,fsd-card" },
> + {},
> +};
> +MODULE_DEVICE_TABLE(of, fsd_device_id);
> +
> +static struct platform_driver fsd_platform_driver = {
> + .driver = {
> + .name = "fsd-card",
> + .of_match_table = of_match_ptr(fsd_device_id),

of_match_ptr comes with maybe_unused. Or drop it.

Best regards,
Krzysztof