root/sound/soc/spear/spdif_in.c
/*
 * ALSA SoC SPDIF In Audio Layer for spear processors
 *
 * Copyright (C) 2012 ST Microelectronics
 * Vipin Kumar <vipin.kumar@st.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2. This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/ioport.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <sound/dmaengine_pcm.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>
#include <sound/spear_dma.h>
#include <sound/spear_spdif.h>
#include "spdif_in_regs.h"
#include "spear_pcm.h"

struct spdif_in_params {
        u32 format;
};

struct spdif_in_dev {
        struct clk *clk;
        struct spear_dma_data dma_params;
        struct spdif_in_params saved_params;
        void *io_base;
        struct device *dev;
        void (*reset_perip)(void);
        int irq;
        struct snd_dmaengine_dai_dma_data dma_params_rx;
        struct snd_dmaengine_pcm_config config;
};

static void spdif_in_configure(struct spdif_in_dev *host)
{
        u32 ctrl = SPDIF_IN_PRTYEN | SPDIF_IN_STATEN | SPDIF_IN_USREN |
                SPDIF_IN_VALEN | SPDIF_IN_BLKEN;
        ctrl |= SPDIF_MODE_16BIT | SPDIF_FIFO_THRES_16;

        writel(ctrl, host->io_base + SPDIF_IN_CTRL);
        writel(0xF, host->io_base + SPDIF_IN_IRQ_MASK);
}

static int spdif_in_dai_probe(struct snd_soc_dai *dai)
{
        struct spdif_in_dev *host = snd_soc_dai_get_drvdata(dai);

        host->dma_params_rx.filter_data = &host->dma_params;
        dai->capture_dma_data = &host->dma_params_rx;

        return 0;
}

static void spdif_in_shutdown(struct snd_pcm_substream *substream,
                struct snd_soc_dai *dai)
{
        struct spdif_in_dev *host = snd_soc_dai_get_drvdata(dai);

        if (substream->stream != SNDRV_PCM_STREAM_CAPTURE)
                return;

        writel(0x0, host->io_base + SPDIF_IN_IRQ_MASK);
}

static void spdif_in_format(struct spdif_in_dev *host, u32 format)
{
        u32 ctrl = readl(host->io_base + SPDIF_IN_CTRL);

        switch (format) {
        case SNDRV_PCM_FORMAT_S16_LE:
                ctrl |= SPDIF_XTRACT_16BIT;
                break;

        case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
                ctrl &= ~SPDIF_XTRACT_16BIT;
                break;
        }

        writel(ctrl, host->io_base + SPDIF_IN_CTRL);
}

static int spdif_in_hw_params(struct snd_pcm_substream *substream,
                struct snd_pcm_hw_params *params,
                struct snd_soc_dai *dai)
{
        struct spdif_in_dev *host = snd_soc_dai_get_drvdata(dai);
        u32 format;

        if (substream->stream != SNDRV_PCM_STREAM_CAPTURE)
                return -EINVAL;

        format = params_format(params);
        host->saved_params.format = format;

        return 0;
}

static int spdif_in_trigger(struct snd_pcm_substream *substream, int cmd,
                struct snd_soc_dai *dai)
{
        struct spdif_in_dev *host = snd_soc_dai_get_drvdata(dai);
        u32 ctrl;
        int ret = 0;

        if (substream->stream != SNDRV_PCM_STREAM_CAPTURE)
                return -EINVAL;

        switch (cmd) {
        case SNDRV_PCM_TRIGGER_START:
        case SNDRV_PCM_TRIGGER_RESUME:
        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
                clk_enable(host->clk);
                spdif_in_configure(host);
                spdif_in_format(host, host->saved_params.format);

                ctrl = readl(host->io_base + SPDIF_IN_CTRL);
                ctrl |= SPDIF_IN_SAMPLE | SPDIF_IN_ENB;
                writel(ctrl, host->io_base + SPDIF_IN_CTRL);
                writel(0xF, host->io_base + SPDIF_IN_IRQ_MASK);
                break;

        case SNDRV_PCM_TRIGGER_STOP:
        case SNDRV_PCM_TRIGGER_SUSPEND:
        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
                ctrl = readl(host->io_base + SPDIF_IN_CTRL);
                ctrl &= ~(SPDIF_IN_SAMPLE | SPDIF_IN_ENB);
                writel(ctrl, host->io_base + SPDIF_IN_CTRL);
                writel(0x0, host->io_base + SPDIF_IN_IRQ_MASK);

                if (host->reset_perip)
                        host->reset_perip();
                clk_disable(host->clk);
                break;

        default:
                ret = -EINVAL;
                break;
        }
        return ret;
}

static const struct snd_soc_dai_ops spdif_in_dai_ops = {
        .shutdown       = spdif_in_shutdown,
        .trigger        = spdif_in_trigger,
        .hw_params      = spdif_in_hw_params,
};

static struct snd_soc_dai_driver spdif_in_dai = {
        .probe = spdif_in_dai_probe,
        .capture = {
                .channels_min = 2,
                .channels_max = 2,
                .rates = (SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
                                 SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000 | \
                                 SNDRV_PCM_RATE_192000),
                .formats = SNDRV_PCM_FMTBIT_S16_LE | \
                           SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE,
        },
        .ops = &spdif_in_dai_ops,
};

static const struct snd_soc_component_driver spdif_in_component = {
        .name                   = "spdif-in",
        .legacy_dai_naming      = 1,
};

static irqreturn_t spdif_in_irq(int irq, void *arg)
{
        struct spdif_in_dev *host = (struct spdif_in_dev *)arg;

        u32 irq_status = readl(host->io_base + SPDIF_IN_IRQ);

        if (!irq_status)
                return IRQ_NONE;

        if (irq_status & SPDIF_IRQ_FIFOWRITE)
                dev_err(host->dev, "spdif in: fifo write error");
        if (irq_status & SPDIF_IRQ_EMPTYFIFOREAD)
                dev_err(host->dev, "spdif in: empty fifo read error");
        if (irq_status & SPDIF_IRQ_FIFOFULL)
                dev_err(host->dev, "spdif in: fifo full error");
        if (irq_status & SPDIF_IRQ_OUTOFRANGE)
                dev_err(host->dev, "spdif in: out of range error");

        writel(0, host->io_base + SPDIF_IN_IRQ);

        return IRQ_HANDLED;
}

static int spdif_in_probe(struct platform_device *pdev)
{
        struct spdif_in_dev *host;
        struct spear_spdif_platform_data *pdata;
        struct resource *res_fifo;
        void __iomem *io_base;
        int ret;

        io_base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(io_base))
                return PTR_ERR(io_base);

        res_fifo = platform_get_resource(pdev, IORESOURCE_IO, 0);
        if (!res_fifo)
                return -EINVAL;

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

        host->io_base = io_base;
        host->irq = platform_get_irq(pdev, 0);
        if (host->irq < 0) {
                dev_warn(&pdev->dev, "failed to get IRQ: %d\n", host->irq);
                return host->irq;
        }

        host->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(host->clk))
                return PTR_ERR(host->clk);

        pdata = dev_get_platdata(&pdev->dev);

        if (!pdata)
                return -EINVAL;

        host->dma_params.data = pdata->dma_params;
        host->dma_params.addr = res_fifo->start;
        host->dma_params.max_burst = 16;
        host->dma_params.addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
        host->reset_perip = pdata->reset_perip;

        host->dev = &pdev->dev;
        dev_set_drvdata(&pdev->dev, host);

        ret = devm_request_irq(&pdev->dev, host->irq, spdif_in_irq, 0,
                        "spdif-in", host);
        if (ret) {
                dev_warn(&pdev->dev, "request_irq failed\n");
                return ret;
        }

        ret = devm_snd_soc_register_component(&pdev->dev, &spdif_in_component,
                                              &spdif_in_dai, 1);
        if (ret)
                return ret;

        return devm_spear_pcm_platform_register(&pdev->dev, &host->config,
                                                pdata->filter);
}

static struct platform_driver spdif_in_driver = {
        .probe          = spdif_in_probe,
        .driver         = {
                .name   = "spdif-in",
        },
};

module_platform_driver(spdif_in_driver);

MODULE_AUTHOR("Vipin Kumar <vipin.kumar@st.com>");
MODULE_DESCRIPTION("SPEAr SPDIF IN SoC Interface");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:spdif_in");