linux/sound/soc/fsl/mpc5200_psc_i2s.c
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   1/*
   2 * Freescale MPC5200 PSC in I2S mode
   3 * ALSA SoC Digital Audio Interface (DAI) driver
   4 *
   5 * Copyright (C) 2008 Secret Lab Technologies Ltd.
   6 * Copyright (C) 2009 Jon Smirl, Digispeaker
   7 */
   8
   9#include <linux/module.h>
  10#include <linux/of_device.h>
  11#include <linux/of_platform.h>
  12
  13#include <sound/pcm.h>
  14#include <sound/pcm_params.h>
  15#include <sound/soc.h>
  16
  17#include <asm/mpc52xx_psc.h>
  18
  19#include "mpc5200_psc_i2s.h"
  20#include "mpc5200_dma.h"
  21
  22/**
  23 * PSC_I2S_RATES: sample rates supported by the I2S
  24 *
  25 * This driver currently only supports the PSC running in I2S slave mode,
  26 * which means the codec determines the sample rate.  Therefore, we tell
  27 * ALSA that we support all rates and let the codec driver decide what rates
  28 * are really supported.
  29 */
  30#define PSC_I2S_RATES (SNDRV_PCM_RATE_5512 | SNDRV_PCM_RATE_8000_192000 | \
  31                        SNDRV_PCM_RATE_CONTINUOUS)
  32
  33/**
  34 * PSC_I2S_FORMATS: audio formats supported by the PSC I2S mode
  35 */
  36#define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
  37                         SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE)
  38
  39static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
  40                                 struct snd_pcm_hw_params *params,
  41                                 struct snd_soc_dai *dai)
  42{
  43        struct snd_soc_pcm_runtime *rtd = substream->private_data;
  44        struct psc_dma *psc_dma = rtd->dai->cpu_dai->private_data;
  45        u32 mode;
  46
  47        dev_dbg(psc_dma->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
  48                " periods=%i buffer_size=%i  buffer_bytes=%i\n",
  49                __func__, substream, params_period_size(params),
  50                params_period_bytes(params), params_periods(params),
  51                params_buffer_size(params), params_buffer_bytes(params));
  52
  53        switch (params_format(params)) {
  54        case SNDRV_PCM_FORMAT_S8:
  55                mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
  56                break;
  57        case SNDRV_PCM_FORMAT_S16_BE:
  58                mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
  59                break;
  60        case SNDRV_PCM_FORMAT_S24_BE:
  61                mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
  62                break;
  63        case SNDRV_PCM_FORMAT_S32_BE:
  64                mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
  65                break;
  66        default:
  67                dev_dbg(psc_dma->dev, "invalid format\n");
  68                return -EINVAL;
  69        }
  70        out_be32(&psc_dma->psc_regs->sicr, psc_dma->sicr | mode);
  71
  72        return 0;
  73}
  74
  75/**
  76 * psc_i2s_set_sysclk: set the clock frequency and direction
  77 *
  78 * This function is called by the machine driver to tell us what the clock
  79 * frequency and direction are.
  80 *
  81 * Currently, we only support operating as a clock slave (SND_SOC_CLOCK_IN),
  82 * and we don't care about the frequency.  Return an error if the direction
  83 * is not SND_SOC_CLOCK_IN.
  84 *
  85 * @clk_id: reserved, should be zero
  86 * @freq: the frequency of the given clock ID, currently ignored
  87 * @dir: SND_SOC_CLOCK_IN (clock slave) or SND_SOC_CLOCK_OUT (clock master)
  88 */
  89static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
  90                              int clk_id, unsigned int freq, int dir)
  91{
  92        struct psc_dma *psc_dma = cpu_dai->private_data;
  93        dev_dbg(psc_dma->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
  94                                cpu_dai, dir);
  95        return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
  96}
  97
  98/**
  99 * psc_i2s_set_fmt: set the serial format.
 100 *
 101 * This function is called by the machine driver to tell us what serial
 102 * format to use.
 103 *
 104 * This driver only supports I2S mode.  Return an error if the format is
 105 * not SND_SOC_DAIFMT_I2S.
 106 *
 107 * @format: one of SND_SOC_DAIFMT_xxx
 108 */
 109static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
 110{
 111        struct psc_dma *psc_dma = cpu_dai->private_data;
 112        dev_dbg(psc_dma->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
 113                                cpu_dai, format);
 114        return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
 115}
 116
 117/* ---------------------------------------------------------------------
 118 * ALSA SoC Bindings
 119 *
 120 * - Digital Audio Interface (DAI) template
 121 * - create/destroy dai hooks
 122 */
 123
 124/**
 125 * psc_i2s_dai_template: template CPU Digital Audio Interface
 126 */
 127static struct snd_soc_dai_ops psc_i2s_dai_ops = {
 128        .hw_params      = psc_i2s_hw_params,
 129        .set_sysclk     = psc_i2s_set_sysclk,
 130        .set_fmt        = psc_i2s_set_fmt,
 131};
 132
 133struct snd_soc_dai psc_i2s_dai[] = {{
 134        .name   = "I2S",
 135        .playback = {
 136                .channels_min = 2,
 137                .channels_max = 2,
 138                .rates = PSC_I2S_RATES,
 139                .formats = PSC_I2S_FORMATS,
 140        },
 141        .capture = {
 142                .channels_min = 2,
 143                .channels_max = 2,
 144                .rates = PSC_I2S_RATES,
 145                .formats = PSC_I2S_FORMATS,
 146        },
 147        .ops = &psc_i2s_dai_ops,
 148} };
 149EXPORT_SYMBOL_GPL(psc_i2s_dai);
 150
 151/* ---------------------------------------------------------------------
 152 * OF platform bus binding code:
 153 * - Probe/remove operations
 154 * - OF device match table
 155 */
 156static int __devinit psc_i2s_of_probe(struct of_device *op,
 157                                      const struct of_device_id *match)
 158{
 159        int rc;
 160        struct psc_dma *psc_dma;
 161        struct mpc52xx_psc __iomem *regs;
 162
 163        rc = mpc5200_audio_dma_create(op);
 164        if (rc != 0)
 165                return rc;
 166
 167        rc = snd_soc_register_dais(psc_i2s_dai, ARRAY_SIZE(psc_i2s_dai));
 168        if (rc != 0) {
 169                pr_err("Failed to register DAI\n");
 170                return 0;
 171        }
 172
 173        psc_dma = dev_get_drvdata(&op->dev);
 174        regs = psc_dma->psc_regs;
 175
 176        /* Configure the serial interface mode; defaulting to CODEC8 mode */
 177        psc_dma->sicr = MPC52xx_PSC_SICR_DTS1 | MPC52xx_PSC_SICR_I2S |
 178                        MPC52xx_PSC_SICR_CLKPOL;
 179        out_be32(&psc_dma->psc_regs->sicr,
 180                 psc_dma->sicr | MPC52xx_PSC_SICR_SIM_CODEC_8);
 181
 182        /* Check for the codec handle.  If it is not present then we
 183         * are done */
 184        if (!of_get_property(op->node, "codec-handle", NULL))
 185                return 0;
 186
 187        /* Due to errata in the dma mode; need to line up enabling
 188         * the transmitter with a transition on the frame sync
 189         * line */
 190
 191        /* first make sure it is low */
 192        while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) != 0)
 193                ;
 194        /* then wait for the transition to high */
 195        while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) == 0)
 196                ;
 197        /* Finally, enable the PSC.
 198         * Receiver must always be enabled; even when we only want
 199         * transmit.  (see 15.3.2.3 of MPC5200B User's Guide) */
 200
 201        /* Go */
 202        out_8(&psc_dma->psc_regs->command,
 203                        MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
 204
 205        return 0;
 206
 207}
 208
 209static int __devexit psc_i2s_of_remove(struct of_device *op)
 210{
 211        return mpc5200_audio_dma_destroy(op);
 212}
 213
 214/* Match table for of_platform binding */
 215static struct of_device_id psc_i2s_match[] __devinitdata = {
 216        { .compatible = "fsl,mpc5200-psc-i2s", },
 217        { .compatible = "fsl,mpc5200b-psc-i2s", },
 218        {}
 219};
 220MODULE_DEVICE_TABLE(of, psc_i2s_match);
 221
 222static struct of_platform_driver psc_i2s_driver = {
 223        .match_table = psc_i2s_match,
 224        .probe = psc_i2s_of_probe,
 225        .remove = __devexit_p(psc_i2s_of_remove),
 226        .driver = {
 227                .name = "mpc5200-psc-i2s",
 228                .owner = THIS_MODULE,
 229        },
 230};
 231
 232/* ---------------------------------------------------------------------
 233 * Module setup and teardown; simply register the of_platform driver
 234 * for the PSC in I2S mode.
 235 */
 236static int __init psc_i2s_init(void)
 237{
 238        return of_register_platform_driver(&psc_i2s_driver);
 239}
 240module_init(psc_i2s_init);
 241
 242static void __exit psc_i2s_exit(void)
 243{
 244        of_unregister_platform_driver(&psc_i2s_driver);
 245}
 246module_exit(psc_i2s_exit);
 247
 248MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 249MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
 250MODULE_LICENSE("GPL");
 251
 252