axg-card.c

// SPDX-License-Identifier: (GPL-2.0 OR MIT)
//
// Copyright (c) 2018 BayLibre, SAS.
// Author: Jerome Brunet <jbrunet@baylibre.com>

#include <linux/module.h>
#include <linux/of_platform.h>
#include <sound/soc.h>
#include <sound/soc-dai.h>

#include "axg-tdm.h"

struct axg_card {
	struct snd_soc_card card;
	void **link_data;
};

struct axg_dai_link_tdm_mask {
	u32 tx;
	u32 rx;
};

struct axg_dai_link_tdm_data {
	unsigned int mclk_fs;
	unsigned int slots;
	unsigned int slot_width;
	u32 *tx_mask;
	u32 *rx_mask;
	struct axg_dai_link_tdm_mask *codec_masks;
};

#define PREFIX "amlogic,"

static int axg_card_reallocate_links(struct axg_card *priv,
				     unsigned int num_links)
{
	struct snd_soc_dai_link *links;
	void **ldata;

	links = krealloc(priv->card.dai_link,
			 num_links * sizeof(*priv->card.dai_link),
			 GFP_KERNEL | __GFP_ZERO);
	ldata = krealloc(priv->link_data,
			 num_links * sizeof(*priv->link_data),
			 GFP_KERNEL | __GFP_ZERO);

	if (!links || !ldata) {
		dev_err(priv->card.dev, "failed to allocate links\n");
		return -ENOMEM;
	}

	priv->card.dai_link = links;
	priv->link_data = ldata;
	priv->card.num_links = num_links;
	return 0;
}

static int axg_card_parse_dai(struct snd_soc_card *card,
			      struct device_node *node,
			      struct device_node **dai_of_node,
			      const char **dai_name)
{
	struct of_phandle_args args;
	int ret;

	if (!dai_name || !dai_of_node || !node)
		return -EINVAL;

	ret = of_parse_phandle_with_args(node, "sound-dai",
					 "#sound-dai-cells", 0, &args);
	if (ret) {
		if (ret != -EPROBE_DEFER)
			dev_err(card->dev, "can't parse dai %d\n", ret);
		return ret;
	}
	*dai_of_node = args.np;

	return snd_soc_get_dai_name(&args, dai_name);
}

static int axg_card_set_link_name(struct snd_soc_card *card,
				  struct snd_soc_dai_link *link,
				  const char *prefix)
{
	char *name = devm_kasprintf(card->dev, GFP_KERNEL, "%s.%s",
				    prefix, link->cpu_of_node->full_name);
	if (!name)
		return -ENOMEM;

	link->name = name;
	link->stream_name = name;

	return 0;
}

static void axg_card_clean_references(struct axg_card *priv)
{
	struct snd_soc_card *card = &priv->card;
	struct snd_soc_dai_link *link;
	struct snd_soc_dai_link_component *codec;
	int i, j;

	if (card->dai_link) {
		for_each_card_prelinks(card, i, link) {
			of_node_put(link->cpu_of_node);
			for_each_link_codecs(link, j, codec)
				of_node_put(codec->of_node);
		}
	}

	if (card->aux_dev) {
		for (i = 0; i < card->num_aux_devs; i++)
			of_node_put(card->aux_dev[i].codec_of_node);
	}

	kfree(card->dai_link);
	kfree(priv->link_data);
}

static int axg_card_add_aux_devices(struct snd_soc_card *card)
{
	struct device_node *node = card->dev->of_node;
	struct snd_soc_aux_dev *aux;
	int num, i;

	num = of_count_phandle_with_args(node, "audio-aux-devs", NULL);
	if (num == -ENOENT) {
		/*
		 * It is ok to have no auxiliary devices but for this card it
		 * is a strange situtation. Let's warn the about it.
		 */
		dev_warn(card->dev, "card has no auxiliary devices\n");
		return 0;
	} else if (num < 0) {
		dev_err(card->dev, "error getting auxiliary devices: %d\n",
			num);
		return num;
	}

	aux = devm_kcalloc(card->dev, num, sizeof(*aux), GFP_KERNEL);
	if (!aux)
		return -ENOMEM;
	card->aux_dev = aux;
	card->num_aux_devs = num;

	for (i = 0; i < card->num_aux_devs; i++, aux++) {
		aux->codec_of_node =
			of_parse_phandle(node, "audio-aux-devs", i);
		if (!aux->codec_of_node)
			return -EINVAL;
	}

	return 0;
}

static int axg_card_tdm_be_hw_params(struct snd_pcm_substream *substream,
				     struct snd_pcm_hw_params *params)
{
	struct snd_soc_pcm_runtime *rtd = substream->private_data;
	struct axg_card *priv = snd_soc_card_get_drvdata(rtd->card);
	struct axg_dai_link_tdm_data *be =
		(struct axg_dai_link_tdm_data *)priv->link_data[rtd->num];
	struct snd_soc_dai *codec_dai;
	unsigned int mclk;
	int ret, i;

	if (be->mclk_fs) {
		mclk = params_rate(params) * be->mclk_fs;

		for_each_rtd_codec_dai(rtd, i, codec_dai) {
			ret = snd_soc_dai_set_sysclk(codec_dai, 0, mclk,
						     SND_SOC_CLOCK_IN);
			if (ret && ret != -ENOTSUPP)
				return ret;
		}

		ret = snd_soc_dai_set_sysclk(rtd->cpu_dai, 0, mclk,
					     SND_SOC_CLOCK_OUT);
		if (ret && ret != -ENOTSUPP)
			return ret;
	}

	return 0;
}

static const struct snd_soc_ops axg_card_tdm_be_ops = {
	.hw_params = axg_card_tdm_be_hw_params,
};

static int axg_card_tdm_dai_init(struct snd_soc_pcm_runtime *rtd)
{
	struct axg_card *priv = snd_soc_card_get_drvdata(rtd->card);
	struct axg_dai_link_tdm_data *be =
		(struct axg_dai_link_tdm_data *)priv->link_data[rtd->num];
	struct snd_soc_dai *codec_dai;
	int ret, i;

	for_each_rtd_codec_dai(rtd, i, codec_dai) {
		ret = snd_soc_dai_set_tdm_slot(codec_dai,
					       be->codec_masks[i].tx,
					       be->codec_masks[i].rx,
					       be->slots, be->slot_width);
		if (ret && ret != -ENOTSUPP) {
			dev_err(codec_dai->dev,
				"setting tdm link slots failed\n");
			return ret;
		}
	}

	ret = axg_tdm_set_tdm_slots(rtd->cpu_dai, be->tx_mask, be->rx_mask,
				    be->slots, be->slot_width);
	if (ret) {
		dev_err(rtd->cpu_dai->dev, "setting tdm link slots failed\n");
		return ret;
	}

	return 0;
}

static int axg_card_tdm_dai_lb_init(struct snd_soc_pcm_runtime *rtd)
{
	struct axg_card *priv = snd_soc_card_get_drvdata(rtd->card);
	struct axg_dai_link_tdm_data *be =
		(struct axg_dai_link_tdm_data *)priv->link_data[rtd->num];
	int ret;

	/* The loopback rx_mask is the pad tx_mask */
	ret = axg_tdm_set_tdm_slots(rtd->cpu_dai, NULL, be->tx_mask,
				    be->slots, be->slot_width);
	if (ret) {
		dev_err(rtd->cpu_dai->dev, "setting tdm link slots failed\n");
		return ret;
	}

	return 0;
}

static int axg_card_add_tdm_loopback(struct snd_soc_card *card,
				     int *index)
{
	struct axg_card *priv = snd_soc_card_get_drvdata(card);
	struct snd_soc_dai_link *pad = &card->dai_link[*index];
	struct snd_soc_dai_link *lb;
	int ret;

	/* extend links */
	ret = axg_card_reallocate_links(priv, card->num_links + 1);
	if (ret)
		return ret;

	lb = &card->dai_link[*index + 1];

	lb->name = kasprintf(GFP_KERNEL, "%s-lb", pad->name);
	if (!lb->name)
		return -ENOMEM;

	lb->stream_name = lb->name;
	lb->cpu_of_node = pad->cpu_of_node;
	lb->cpu_dai_name = "TDM Loopback";
	lb->codec_name = "snd-soc-dummy";
	lb->codec_dai_name = "snd-soc-dummy-dai";
	lb->dpcm_capture = 1;
	lb->no_pcm = 1;
	lb->ops = &axg_card_tdm_be_ops;
	lb->init = axg_card_tdm_dai_lb_init;

	/* Provide the same link data to the loopback */
	priv->link_data[*index + 1] = priv->link_data[*index];

	/*
	 * axg_card_clean_references() will iterate over this link,
	 * make sure the node count is balanced
	 */
	of_node_get(lb->cpu_of_node);

	/* Let add_links continue where it should */
	*index += 1;

	return 0;
}

static unsigned int axg_card_parse_daifmt(struct device_node *node,
					  struct device_node *cpu_node)
{
	struct device_node *bitclkmaster = NULL;
	struct device_node *framemaster = NULL;
	unsigned int daifmt;

	daifmt = snd_soc_of_parse_daifmt(node, PREFIX,
					 &bitclkmaster, &framemaster);
	daifmt &= ~SND_SOC_DAIFMT_MASTER_MASK;

	/* If no master is provided, default to cpu master */
	if (!bitclkmaster || bitclkmaster == cpu_node) {
		daifmt |= (!framemaster || framemaster == cpu_node) ?
			SND_SOC_DAIFMT_CBS_CFS : SND_SOC_DAIFMT_CBS_CFM;
	} else {
		daifmt |= (!framemaster || framemaster == cpu_node) ?
			SND_SOC_DAIFMT_CBM_CFS : SND_SOC_DAIFMT_CBM_CFM;
	}

	of_node_put(bitclkmaster);
	of_node_put(framemaster);

	return daifmt;
}

static int axg_card_parse_cpu_tdm_slots(struct snd_soc_card *card,
					struct snd_soc_dai_link *link,
					struct device_node *node,
					struct axg_dai_link_tdm_data *be)
{
	char propname[32];
	u32 tx, rx;
	int i;

	be->tx_mask = devm_kcalloc(card->dev, AXG_TDM_NUM_LANES,
				   sizeof(*be->tx_mask), GFP_KERNEL);
	be->rx_mask = devm_kcalloc(card->dev, AXG_TDM_NUM_LANES,
				   sizeof(*be->rx_mask), GFP_KERNEL);
	if (!be->tx_mask || !be->rx_mask)
		return -ENOMEM;

	for (i = 0, tx = 0; i < AXG_TDM_NUM_LANES; i++) {
		snprintf(propname, 32, "dai-tdm-slot-tx-mask-%d", i);
		snd_soc_of_get_slot_mask(node, propname, &be->tx_mask[i]);
		tx = max(tx, be->tx_mask[i]);
	}

	/* Disable playback is the interface has no tx slots */
	if (!tx)
		link->dpcm_playback = 0;

	for (i = 0, rx = 0; i < AXG_TDM_NUM_LANES; i++) {
		snprintf(propname, 32, "dai-tdm-slot-rx-mask-%d", i);
		snd_soc_of_get_slot_mask(node, propname, &be->rx_mask[i]);
		rx = max(rx, be->rx_mask[i]);
	}

	/* Disable capture is the interface has no rx slots */
	if (!rx)
		link->dpcm_capture = 0;

	/* ... but the interface should at least have one of them */
	if (!tx && !rx) {
		dev_err(card->dev, "tdm link has no cpu slots\n");
		return -EINVAL;
	}

	of_property_read_u32(node, "dai-tdm-slot-num", &be->slots);
	if (!be->slots) {
		/*
		 * If the slot number is not provided, set it such as it
		 * accommodates the largest mask
		 */
		be->slots = fls(max(tx, rx));
	} else if (be->slots < fls(max(tx, rx)) || be->slots > 32) {
		/*
		 * Error if the slots can't accommodate the largest mask or
		 * if it is just too big
		 */
		dev_err(card->dev, "bad slot number\n");
		return -EINVAL;
	}

	of_property_read_u32(node, "dai-tdm-slot-width", &be->slot_width);

	return 0;
}

static int axg_card_parse_codecs_masks(struct snd_soc_card *card,
				       struct snd_soc_dai_link *link,
				       struct device_node *node,
				       struct axg_dai_link_tdm_data *be)
{
	struct axg_dai_link_tdm_mask *codec_mask;
	struct device_node *np;

	codec_mask = devm_kcalloc(card->dev, link->num_codecs,
				  sizeof(*codec_mask), GFP_KERNEL);
	if (!codec_mask)
		return -ENOMEM;

	be->codec_masks = codec_mask;

	for_each_child_of_node(node, np) {
		snd_soc_of_get_slot_mask(np, "dai-tdm-slot-rx-mask",
					 &codec_mask->rx);
		snd_soc_of_get_slot_mask(np, "dai-tdm-slot-tx-mask",
					 &codec_mask->tx);

		codec_mask++;
	}

	return 0;
}

static int axg_card_parse_tdm(struct snd_soc_card *card,
			      struct device_node *node,
			      int *index)
{
	struct axg_card *priv = snd_soc_card_get_drvdata(card);
	struct snd_soc_dai_link *link = &card->dai_link[*index];
	struct axg_dai_link_tdm_data *be;
	int ret;

	/* Allocate tdm link parameters */
	be = devm_kzalloc(card->dev, sizeof(*be), GFP_KERNEL);
	if (!be)
		return -ENOMEM;
	priv->link_data[*index] = be;

	/* Setup tdm link */
	link->ops = &axg_card_tdm_be_ops;
	link->init = axg_card_tdm_dai_init;
	link->dai_fmt = axg_card_parse_daifmt(node, link->cpu_of_node);

	of_property_read_u32(node, "mclk-fs", &be->mclk_fs);

	ret = axg_card_parse_cpu_tdm_slots(card, link, node, be);
	if (ret) {
		dev_err(card->dev, "error parsing tdm link slots\n");
		return ret;
	}

	ret = axg_card_parse_codecs_masks(card, link, node, be);
	if (ret)
		return ret;

	/* Add loopback if the pad dai has playback */
	if (link->dpcm_playback) {
		ret = axg_card_add_tdm_loopback(card, index);
		if (ret)
			return ret;
	}

	return 0;
}

static int axg_card_set_be_link(struct snd_soc_card *card,
				struct snd_soc_dai_link *link,
				struct device_node *node)
{
	struct snd_soc_dai_link_component *codec;
	struct device_node *np;
	int ret, num_codecs;

	link->no_pcm = 1;
	link->dpcm_playback = 1;
	link->dpcm_capture = 1;

	num_codecs = of_get_child_count(node);
	if (!num_codecs) {
		dev_err(card->dev, "be link %s has no codec\n",
			node->full_name);
		return -EINVAL;
	}

	codec = devm_kcalloc(card->dev, num_codecs, sizeof(*codec), GFP_KERNEL);
	if (!codec)
		return -ENOMEM;

	link->codecs = codec;
	link->num_codecs = num_codecs;

	for_each_child_of_node(node, np) {
		ret = axg_card_parse_dai(card, np, &codec->of_node,
					 &codec->dai_name);
		if (ret) {
			of_node_put(np);
			return ret;
		}

		codec++;
	}

	ret = axg_card_set_link_name(card, link, "be");
	if (ret)
		dev_err(card->dev, "error setting %pOFn link name\n", np);

	return ret;
}

static int axg_card_set_fe_link(struct snd_soc_card *card,
				struct snd_soc_dai_link *link,
				bool is_playback)
{
	link->dynamic = 1;
	link->dpcm_merged_format = 1;
	link->dpcm_merged_chan = 1;
	link->dpcm_merged_rate = 1;
	link->codec_dai_name = "snd-soc-dummy-dai";
	link->codec_name = "snd-soc-dummy";

	if (is_playback)
		link->dpcm_playback = 1;
	else
		link->dpcm_capture = 1;

	return axg_card_set_link_name(card, link, "fe");
}

static int axg_card_cpu_is_capture_fe(struct device_node *np)
{
	return of_device_is_compatible(np, PREFIX "axg-toddr");
}

static int axg_card_cpu_is_playback_fe(struct device_node *np)
{
	return of_device_is_compatible(np, PREFIX "axg-frddr");
}

static int axg_card_cpu_is_tdm_iface(struct device_node *np)
{
	return of_device_is_compatible(np, PREFIX "axg-tdm-iface");
}

static int axg_card_add_link(struct snd_soc_card *card, struct device_node *np,
			     int *index)
{
	struct snd_soc_dai_link *dai_link = &card->dai_link[*index];
	int ret;

	ret = axg_card_parse_dai(card, np, &dai_link->cpu_of_node,
				 &dai_link->cpu_dai_name);
	if (ret)
		return ret;

	if (axg_card_cpu_is_playback_fe(dai_link->cpu_of_node))
		ret = axg_card_set_fe_link(card, dai_link, true);
	else if (axg_card_cpu_is_capture_fe(dai_link->cpu_of_node))
		ret = axg_card_set_fe_link(card, dai_link, false);
	else
		ret = axg_card_set_be_link(card, dai_link, np);

	if (ret)
		return ret;

	if (axg_card_cpu_is_tdm_iface(dai_link->cpu_of_node))
		ret = axg_card_parse_tdm(card, np, index);

	return ret;
}

static int axg_card_add_links(struct snd_soc_card *card)
{
	struct axg_card *priv = snd_soc_card_get_drvdata(card);
	struct device_node *node = card->dev->of_node;
	struct device_node *np;
	int num, i, ret;

	num = of_get_child_count(node);
	if (!num) {
		dev_err(card->dev, "card has no links\n");
		return -EINVAL;
	}

	ret = axg_card_reallocate_links(priv, num);
	if (ret)
		return ret;

	i = 0;
	for_each_child_of_node(node, np) {
		ret = axg_card_add_link(card, np, &i);
		if (ret) {
			of_node_put(np);
			return ret;
		}

		i++;
	}

	return 0;
}

static int axg_card_parse_of_optional(struct snd_soc_card *card,
				      const char *propname,
				      int (*func)(struct snd_soc_card *c,
						  const char *p))
{
	/* If property is not provided, don't fail ... */
	if (!of_property_read_bool(card->dev->of_node, propname))
		return 0;

	/* ... but do fail if it is provided and the parsing fails */
	return func(card, propname);
}

static const struct of_device_id axg_card_of_match[] = {
	{ .compatible = "amlogic,axg-sound-card", },
	{}
};
MODULE_DEVICE_TABLE(of, axg_card_of_match);

static int axg_card_probe(struct platform_device *pdev)
{
	struct device *dev = &pdev->dev;
	struct axg_card *priv;
	int ret;

	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
	if (!priv)
		return -ENOMEM;

	platform_set_drvdata(pdev, priv);
	snd_soc_card_set_drvdata(&priv->card, priv);

	priv->card.owner = THIS_MODULE;
	priv->card.dev = dev;

	ret = snd_soc_of_parse_card_name(&priv->card, "model");
	if (ret < 0)
		return ret;

	ret = axg_card_parse_of_optional(&priv->card, "audio-routing",
					 snd_soc_of_parse_audio_routing);
	if (ret) {
		dev_err(dev, "error while parsing routing\n");
		return ret;
	}

	ret = axg_card_parse_of_optional(&priv->card, "audio-widgets",
					 snd_soc_of_parse_audio_simple_widgets);
	if (ret) {
		dev_err(dev, "error while parsing widgets\n");
		return ret;
	}

	ret = axg_card_add_links(&priv->card);
	if (ret)
		goto out_err;

	ret = axg_card_add_aux_devices(&priv->card);
	if (ret)
		goto out_err;

	ret = devm_snd_soc_register_card(dev, &priv->card);
	if (ret)
		goto out_err;

	return 0;

out_err:
	axg_card_clean_references(priv);
	return ret;
}

static int axg_card_remove(struct platform_device *pdev)
{
	struct axg_card *priv = platform_get_drvdata(pdev);

	axg_card_clean_references(priv);

	return 0;
}

static struct platform_driver axg_card_pdrv = {
	.probe = axg_card_probe,
	.remove = axg_card_remove,
	.driver = {
		.name = "axg-sound-card",
		.of_match_table = axg_card_of_match,
	},
};
module_platform_driver(axg_card_pdrv);

MODULE_DESCRIPTION("Amlogic AXG ALSA machine driver");
MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
MODULE_LICENSE("GPL v2");