mpc5200_psc_i2s.c

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/*
 * Freescale MPC5200 PSC in I2S mode
 * ALSA SoC Digital Audio Interface (DAI) driver
 *
 * Copyright (C) 2008 Secret Lab Technologies Ltd.
 * Copyright (C) 2009 Jon Smirl, Digispeaker
 */

#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/of_platform.h>

#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/soc.h>

#include <asm/mpc52xx_psc.h>

#include "mpc5200_dma.h"

#define PSC_I2S_RATES (SNDRV_PCM_RATE_5512 | SNDRV_PCM_RATE_8000_192000 | \
            SNDRV_PCM_RATE_CONTINUOUS)

#define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
             SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE)

static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
                 struct snd_pcm_hw_params *params,
                 struct snd_soc_dai *dai)
{
    struct snd_soc_pcm_runtime *rtd = substream->private_data;
    struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
    u32 mode;

    dev_dbg(psc_dma->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
        " periods=%i buffer_size=%i  buffer_bytes=%i\n",
        __func__, substream, params_period_size(params),
        params_period_bytes(params), params_periods(params),
        params_buffer_size(params), params_buffer_bytes(params));

    switch (params_format(params)) {
    case SNDRV_PCM_FORMAT_S8:
        mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
        break;
    case SNDRV_PCM_FORMAT_S16_BE:
        mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
        break;
    case SNDRV_PCM_FORMAT_S24_BE:
        mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
        break;
    case SNDRV_PCM_FORMAT_S32_BE:
        mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
        break;
    default:
        dev_dbg(psc_dma->dev, "invalid format\n");
        return -EINVAL;
    }
    out_be32(&psc_dma->psc_regs->sicr, psc_dma->sicr | mode);

    return 0;
}

static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
                  int clk_id, unsigned int freq, int dir)
{
    struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
    dev_dbg(psc_dma->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
                cpu_dai, dir);
    return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
}

static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
{
    struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
    dev_dbg(psc_dma->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
                cpu_dai, format);
    return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
}

/* ---------------------------------------------------------------------
 * ALSA SoC Bindings
 *
 * - Digital Audio Interface (DAI) template
 * - create/destroy dai hooks
 */

static const struct snd_soc_dai_ops psc_i2s_dai_ops = {
    .hw_params  = psc_i2s_hw_params,
    .set_sysclk = psc_i2s_set_sysclk,
    .set_fmt    = psc_i2s_set_fmt,
};

static struct snd_soc_dai_driver psc_i2s_dai[] = {{
    .name = "mpc5200-psc-i2s.0",
    .playback = {
        .stream_name = "I2S Playback",
        .channels_min = 2,
        .channels_max = 2,
        .rates = PSC_I2S_RATES,
        .formats = PSC_I2S_FORMATS,
    },
    .capture = {
        .stream_name = "I2S Capture",
        .channels_min = 2,
        .channels_max = 2,
        .rates = PSC_I2S_RATES,
        .formats = PSC_I2S_FORMATS,
    },
    .ops = &psc_i2s_dai_ops,
} };

/* ---------------------------------------------------------------------
 * OF platform bus binding code:
 * - Probe/remove operations
 * - OF device match table
 */
static int __devinit psc_i2s_of_probe(struct platform_device *op)
{
    int rc;
    struct psc_dma *psc_dma;
    struct mpc52xx_psc __iomem *regs;

    rc = mpc5200_audio_dma_create(op);
    if (rc != 0)
        return rc;

    rc = snd_soc_register_dais(&op->dev, psc_i2s_dai, ARRAY_SIZE(psc_i2s_dai));
    if (rc != 0) {
        pr_err("Failed to register DAI\n");
        return rc;
    }

    psc_dma = dev_get_drvdata(&op->dev);
    regs = psc_dma->psc_regs;

    /* Configure the serial interface mode; defaulting to CODEC8 mode */
    psc_dma->sicr = MPC52xx_PSC_SICR_DTS1 | MPC52xx_PSC_SICR_I2S |
            MPC52xx_PSC_SICR_CLKPOL;
    out_be32(&psc_dma->psc_regs->sicr,
         psc_dma->sicr | MPC52xx_PSC_SICR_SIM_CODEC_8);

    /* Check for the codec handle.  If it is not present then we
     * are done */
    if (!of_get_property(op->dev.of_node, "codec-handle", NULL))
        return 0;

    /* Due to errata in the dma mode; need to line up enabling
     * the transmitter with a transition on the frame sync
     * line */

    /* first make sure it is low */
    while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) != 0)
        ;
    /* then wait for the transition to high */
    while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) == 0)
        ;
    /* Finally, enable the PSC.
     * Receiver must always be enabled; even when we only want
     * transmit.  (see 15.3.2.3 of MPC5200B User's Guide) */

    /* Go */
    out_8(&psc_dma->psc_regs->command,
            MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);

    return 0;

}

static int __devexit psc_i2s_of_remove(struct platform_device *op)
{
    mpc5200_audio_dma_destroy(op);
    snd_soc_unregister_dais(&op->dev, ARRAY_SIZE(psc_i2s_dai));
    return 0;
}

/* Match table for of_platform binding */
static struct of_device_id psc_i2s_match[] __devinitdata = {
    { .compatible = "fsl,mpc5200-psc-i2s", },
    { .compatible = "fsl,mpc5200b-psc-i2s", },
    {}
};
MODULE_DEVICE_TABLE(of, psc_i2s_match);

static struct platform_driver psc_i2s_driver = {
    .probe = psc_i2s_of_probe,
    .remove = __devexit_p(psc_i2s_of_remove),
    .driver = {
        .name = "mpc5200-psc-i2s",
        .owner = THIS_MODULE,
        .of_match_table = psc_i2s_match,
    },
};

module_platform_driver(psc_i2s_driver);

MODULE_AUTHOR("Grant Likely <[email protected]>");
MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
MODULE_LICENSE("GPL");