sound/soc/fsl/mpc5200_psc_i2s.c

   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
  39 static 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  */
  89 static 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  */
 109 static 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  */
 127 static 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
 133 struct 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 } };
 149 EXPORT_SYMBOL_GPL(psc_i2s_dai);
 150
 151 /* ---------------------------------------------------------------------
 152  * OF platform bus binding code:
 153  * - Probe/remove operations
 154  * - OF device match table
 155  */
 156 static 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
 209 static 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 */
 215 static struct of_device_id psc_i2s_match[] __devinitdata = {
 216         { .compatible = "fsl,mpc5200-psc-i2s", },
 217         { .compatible = "fsl,mpc5200b-psc-i2s", },
 218         {}
 219 };
 220 MODULE_DEVICE_TABLE(of, psc_i2s_match);
 221
 222 static 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  */
 236 static int __init psc_i2s_init(void)
 237 {
 238         return of_register_platform_driver(&psc_i2s_driver);
 239 }
 240 module_init(psc_i2s_init);
 241
 242 static void __exit psc_i2s_exit(void)
 243 {
 244         of_unregister_platform_driver(&psc_i2s_driver);
 245 }
 246 module_exit(psc_i2s_exit);
 247
 248 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 249 MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
 250 MODULE_LICENSE("GPL");
 251