root/sound/soc/fsl/imx-rpmsg.c
// SPDX-License-Identifier: GPL-2.0+
// Copyright 2017-2020 NXP

#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/of_reserved_mem.h>
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <sound/soc.h>
#include <sound/jack.h>
#include <sound/control.h>
#include <sound/pcm_params.h>
#include <sound/soc-dapm.h>
#include "imx-pcm-rpmsg.h"

struct imx_rpmsg {
        struct snd_soc_dai_link dai;
        struct snd_soc_card card;
        unsigned long sysclk;
        bool lpa;
};

static struct dev_pm_ops lpa_pm;

static const struct snd_soc_dapm_widget imx_rpmsg_dapm_widgets[] = {
        SND_SOC_DAPM_HP("Headphone Jack", NULL),
        SND_SOC_DAPM_SPK("Ext Spk", NULL),
        SND_SOC_DAPM_MIC("Mic Jack", NULL),
        SND_SOC_DAPM_MIC("Main MIC", NULL),
};

static int imx_rpmsg_late_probe(struct snd_soc_card *card)
{
        struct imx_rpmsg *data = snd_soc_card_get_drvdata(card);
        struct snd_soc_pcm_runtime *rtd = list_first_entry(&card->rtd_list,
                                                           struct snd_soc_pcm_runtime, list);
        struct snd_soc_dai *codec_dai = snd_soc_rtd_to_codec(rtd, 0);
        struct device *dev = card->dev;
        int ret;

        if (data->lpa) {
                struct snd_soc_component *codec_comp;
                struct device_node *codec_np;
                struct device_driver *codec_drv;
                struct device *codec_dev = NULL;

                codec_np = data->dai.codecs->of_node;
                if (codec_np) {
                        struct platform_device *codec_pdev;
                        struct i2c_client *codec_i2c;

                        codec_i2c = of_find_i2c_device_by_node(codec_np);
                        if (codec_i2c)
                                codec_dev = &codec_i2c->dev;
                        if (!codec_dev) {
                                codec_pdev = of_find_device_by_node(codec_np);
                                if (codec_pdev)
                                        codec_dev = &codec_pdev->dev;
                        }
                }
                if (codec_dev) {
                        codec_comp = snd_soc_lookup_component_nolocked(codec_dev, NULL);
                        if (codec_comp) {
                                int i, num_widgets;
                                const char *widgets;
                                struct snd_soc_dapm_context *dapm;

                                num_widgets = of_property_count_strings(data->card.dev->of_node,
                                                                        "ignore-suspend-widgets");
                                for (i = 0; i < num_widgets; i++) {
                                        of_property_read_string_index(data->card.dev->of_node,
                                                                      "ignore-suspend-widgets",
                                                                      i, &widgets);
                                        dapm = snd_soc_component_to_dapm(codec_comp);
                                        snd_soc_dapm_ignore_suspend(dapm, widgets);
                                }
                        }
                        codec_drv = codec_dev->driver;
                        if (codec_drv->pm) {
                                memcpy(&lpa_pm, codec_drv->pm, sizeof(lpa_pm));
                                lpa_pm.suspend = NULL;
                                lpa_pm.resume = NULL;
                                lpa_pm.freeze = NULL;
                                lpa_pm.thaw = NULL;
                                lpa_pm.poweroff = NULL;
                                lpa_pm.restore = NULL;
                                codec_drv->pm = &lpa_pm;
                        }
                        put_device(codec_dev);
                }
        }

        if (!data->sysclk)
                return 0;

        ret = snd_soc_dai_set_sysclk(codec_dai, 0, data->sysclk, SND_SOC_CLOCK_IN);
        if (ret && ret != -ENOTSUPP) {
                dev_err(dev, "failed to set sysclk in %s\n", __func__);
                return ret;
        }

        return 0;
}

static int imx_rpmsg_probe(struct platform_device *pdev)
{
        struct snd_soc_dai_link_component *dlc;
        struct snd_soc_dai *cpu_dai;
        struct device_node *np = NULL;
        struct of_phandle_args args;
        const char *platform_name;
        struct imx_rpmsg *data;
        int ret = 0;

        dlc = devm_kzalloc(&pdev->dev, 3 * sizeof(*dlc), GFP_KERNEL);
        if (!dlc)
                return -ENOMEM;

        data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
        if (!data) {
                ret = -ENOMEM;
                goto fail;
        }

        data->dai.cpus = &dlc[0];
        data->dai.num_cpus = 1;
        data->dai.platforms = &dlc[1];
        data->dai.num_platforms = 1;
        data->dai.codecs = &dlc[2];
        data->dai.num_codecs = 1;

        data->dai.name = "rpmsg hifi";
        data->dai.stream_name = "rpmsg hifi";
        data->dai.dai_fmt = SND_SOC_DAIFMT_I2S |
                            SND_SOC_DAIFMT_NB_NF |
                            SND_SOC_DAIFMT_CBC_CFC;

        /*
         * i.MX rpmsg sound cards work on codec slave mode. MCLK will be
         * disabled by CPU DAI driver in hw_free(). Some codec requires MCLK
         * present at power up/down sequence. So need to set ignore_pmdown_time
         * to power down codec immediately before MCLK is turned off.
         */
        data->dai.ignore_pmdown_time = 1;

        data->dai.cpus->dai_name = pdev->dev.platform_data;
        cpu_dai = snd_soc_find_dai_with_mutex(data->dai.cpus);
        if (!cpu_dai) {
                ret = -EPROBE_DEFER;
                goto fail;
        }
        np = cpu_dai->dev->of_node;
        if (!np) {
                dev_err(&pdev->dev, "failed to parse CPU DAI device node\n");
                ret = -ENODEV;
                goto fail;
        }

        ret = of_reserved_mem_device_init_by_idx(&pdev->dev, np, 0);
        if (ret)
                dev_warn(&pdev->dev, "no reserved DMA memory\n");

        /* Optional codec node */
        ret = of_parse_phandle_with_fixed_args(np, "audio-codec", 0, 0, &args);
        if (ret) {
                *data->dai.codecs = snd_soc_dummy_dlc;
        } else {
                struct clk *clk;

                ret = snd_soc_get_dlc(&args, data->dai.codecs);
                if (ret) {
                        dev_err(&pdev->dev, "Unable to get codec_dai_name\n");
                        goto fail;
                }

                clk = devm_get_clk_from_child(&pdev->dev, args.np, NULL);
                if (!IS_ERR(clk))
                        data->sysclk = clk_get_rate(clk);
        }

        if (!of_property_read_string(np, "fsl,rpmsg-channel-name", &platform_name))
                data->dai.platforms->name = platform_name;
        else
                data->dai.platforms->name = "rpmsg-audio-channel";
        data->dai.playback_only = true;
        data->dai.capture_only = true;
        data->card.num_links = 1;
        data->card.dai_link = &data->dai;

        if (of_property_read_bool(np, "fsl,rpmsg-out"))
                data->dai.capture_only = false;

        if (of_property_read_bool(np, "fsl,rpmsg-in"))
                data->dai.playback_only = false;

        if (data->dai.playback_only && data->dai.capture_only) {
                dev_err(&pdev->dev, "no enabled rpmsg DAI link\n");
                ret = -EINVAL;
                goto fail;
        }

        if (of_property_read_bool(np, "fsl,enable-lpa"))
                data->lpa = true;

        data->card.dev = &pdev->dev;
        data->card.owner = THIS_MODULE;
        data->card.dapm_widgets = imx_rpmsg_dapm_widgets;
        data->card.num_dapm_widgets = ARRAY_SIZE(imx_rpmsg_dapm_widgets);
        data->card.late_probe = imx_rpmsg_late_probe;
        /*
         * Inoder to use common api to get card name and audio routing.
         * Use parent of_node for this device, revert it after finishing using
         */
        data->card.dev->of_node = np;

        ret = snd_soc_of_parse_card_name(&data->card, "model");
        if (ret)
                goto fail;

        if (of_property_present(np, "audio-routing")) {
                ret = snd_soc_of_parse_audio_routing(&data->card, "audio-routing");
                if (ret) {
                        dev_err(&pdev->dev, "failed to parse audio-routing: %d\n", ret);
                        goto fail;
                }
        }

        platform_set_drvdata(pdev, &data->card);
        snd_soc_card_set_drvdata(&data->card, data);
        ret = devm_snd_soc_register_card(&pdev->dev, &data->card);
        if (ret) {
                dev_err_probe(&pdev->dev, ret, "snd_soc_register_card failed\n");
                goto fail;
        }

fail:
        pdev->dev.of_node = NULL;
        return ret;
}

static struct platform_driver imx_rpmsg_driver = {
        .driver = {
                .name = "imx-audio-rpmsg",
                .pm = &snd_soc_pm_ops,
        },
        .probe = imx_rpmsg_probe,
};
module_platform_driver(imx_rpmsg_driver);

MODULE_DESCRIPTION("Freescale SoC Audio RPMSG Machine Driver");
MODULE_AUTHOR("Shengjiu Wang <shengjiu.wang@nxp.com>");
MODULE_ALIAS("platform:imx-audio-rpmsg");
MODULE_LICENSE("GPL v2");