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