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_CONTINUOUS
  30
  31 /**
  32  * PSC_I2S_FORMATS: audio formats supported by the PSC I2S mode
  33  */
  34 #define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
  35                          SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE)
  36
  37 static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
  38                                  struct snd_pcm_hw_params *params,
  39                                  struct snd_soc_dai *dai)
  40 {
  41         struct snd_soc_pcm_runtime *rtd = substream->private_data;
  42         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(rtd->cpu_dai);
  43         u32 mode;
  44
  45         dev_dbg(psc_dma->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
  46                 " periods=%i buffer_size=%i  buffer_bytes=%i\n",
  47                 __func__, substream, params_period_size(params),
  48                 params_period_bytes(params), params_periods(params),
  49                 params_buffer_size(params), params_buffer_bytes(params));
  50
  51         switch (params_format(params)) {
  52         case SNDRV_PCM_FORMAT_S8:
  53                 mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
  54                 break;
  55         case SNDRV_PCM_FORMAT_S16_BE:
  56                 mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
  57                 break;
  58         case SNDRV_PCM_FORMAT_S24_BE:
  59                 mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
  60                 break;
  61         case SNDRV_PCM_FORMAT_S32_BE:
  62                 mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
  63                 break;
  64         default:
  65                 dev_dbg(psc_dma->dev, "invalid format\n");
  66                 return -EINVAL;
  67         }
  68         out_be32(&psc_dma->psc_regs->sicr, psc_dma->sicr | mode);
  69
  70         return 0;
  71 }
  72
  73 /**
  74  * psc_i2s_set_sysclk: set the clock frequency and direction
  75  *
  76  * This function is called by the machine driver to tell us what the clock
  77  * frequency and direction are.
  78  *
  79  * Currently, we only support operating as a clock slave (SND_SOC_CLOCK_IN),
  80  * and we don't care about the frequency.  Return an error if the direction
  81  * is not SND_SOC_CLOCK_IN.
  82  *
  83  * @clk_id: reserved, should be zero
  84  * @freq: the frequency of the given clock ID, currently ignored
  85  * @dir: SND_SOC_CLOCK_IN (clock slave) or SND_SOC_CLOCK_OUT (clock master)
  86  */
  87 static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
  88                               int clk_id, unsigned int freq, int dir)
  89 {
  90         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
  91         dev_dbg(psc_dma->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
  92                                 cpu_dai, dir);
  93         return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
  94 }
  95
  96 /**
  97  * psc_i2s_set_fmt: set the serial format.
  98  *
  99  * This function is called by the machine driver to tell us what serial
 100  * format to use.
 101  *
 102  * This driver only supports I2S mode.  Return an error if the format is
 103  * not SND_SOC_DAIFMT_I2S.
 104  *
 105  * @format: one of SND_SOC_DAIFMT_xxx
 106  */
 107 static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
 108 {
 109         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
 110         dev_dbg(psc_dma->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
 111                                 cpu_dai, format);
 112         return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
 113 }
 114
 115 /* ---------------------------------------------------------------------
 116  * ALSA SoC Bindings
 117  *
 118  * - Digital Audio Interface (DAI) template
 119  * - create/destroy dai hooks
 120  */
 121
 122 /**
 123  * psc_i2s_dai_template: template CPU Digital Audio Interface
 124  */
 125 static const struct snd_soc_dai_ops psc_i2s_dai_ops = {
 126         .hw_params      = psc_i2s_hw_params,
 127         .set_sysclk     = psc_i2s_set_sysclk,
 128         .set_fmt        = psc_i2s_set_fmt,
 129 };
 130
 131 static struct snd_soc_dai_driver psc_i2s_dai[] = {{
 132         .name = "mpc5200-psc-i2s.0",
 133         .playback = {
 134                 .stream_name = "I2S Playback",
 135                 .channels_min = 2,
 136                 .channels_max = 2,
 137                 .rates = PSC_I2S_RATES,
 138                 .formats = PSC_I2S_FORMATS,
 139         },
 140         .capture = {
 141                 .stream_name = "I2S 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
 150 static const struct snd_soc_component_driver psc_i2s_component = {
 151         .name           = "mpc5200-i2s",
 152 };
 153
 154 /* ---------------------------------------------------------------------
 155  * OF platform bus binding code:
 156  * - Probe/remove operations
 157  * - OF device match table
 158  */
 159 static int psc_i2s_of_probe(struct platform_device *op)
 160 {
 161         int rc;
 162         struct psc_dma *psc_dma;
 163         struct mpc52xx_psc __iomem *regs;
 164
 165         rc = mpc5200_audio_dma_create(op);
 166         if (rc != 0)
 167                 return rc;
 168
 169         rc = snd_soc_register_component(&op->dev, &psc_i2s_component,
 170                                         psc_i2s_dai, ARRAY_SIZE(psc_i2s_dai));
 171         if (rc != 0) {
 172                 pr_err("Failed to register DAI\n");
 173                 return rc;
 174         }
 175
 176         psc_dma = dev_get_drvdata(&op->dev);
 177         regs = psc_dma->psc_regs;
 178
 179         /* Configure the serial interface mode; defaulting to CODEC8 mode */
 180         psc_dma->sicr = MPC52xx_PSC_SICR_DTS1 | MPC52xx_PSC_SICR_I2S |
 181                         MPC52xx_PSC_SICR_CLKPOL;
 182         out_be32(&psc_dma->psc_regs->sicr,
 183                  psc_dma->sicr | MPC52xx_PSC_SICR_SIM_CODEC_8);
 184
 185         /* Check for the codec handle.  If it is not present then we
 186          * are done */
 187         if (!of_get_property(op->dev.of_node, "codec-handle", NULL))
 188                 return 0;
 189
 190         /* Due to errata in the dma mode; need to line up enabling
 191          * the transmitter with a transition on the frame sync
 192          * line */
 193
 194         /* first make sure it is low */
 195         while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) != 0)
 196                 ;
 197         /* then wait for the transition to high */
 198         while ((in_8(&regs->ipcr_acr.ipcr) & 0x80) == 0)
 199                 ;
 200         /* Finally, enable the PSC.
 201          * Receiver must always be enabled; even when we only want
 202          * transmit.  (see 15.3.2.3 of MPC5200B User's Guide) */
 203
 204         /* Go */
 205         out_8(&psc_dma->psc_regs->command,
 206                         MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
 207
 208         return 0;
 209
 210 }
 211
 212 static int psc_i2s_of_remove(struct platform_device *op)
 213 {
 214         mpc5200_audio_dma_destroy(op);
 215         snd_soc_unregister_component(&op->dev);
 216         return 0;
 217 }
 218
 219 /* Match table for of_platform binding */
 220 static struct of_device_id psc_i2s_match[] = {
 221         { .compatible = "fsl,mpc5200-psc-i2s", },
 222         { .compatible = "fsl,mpc5200b-psc-i2s", },
 223         {}
 224 };
 225 MODULE_DEVICE_TABLE(of, psc_i2s_match);
 226
 227 static struct platform_driver psc_i2s_driver = {
 228         .probe = psc_i2s_of_probe,
 229         .remove = psc_i2s_of_remove,
 230         .driver = {
 231                 .name = "mpc5200-psc-i2s",
 232                 .of_match_table = psc_i2s_match,
 233         },
 234 };
 235
 236 module_platform_driver(psc_i2s_driver);
 237
 238 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 239 MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
 240 MODULE_LICENSE("GPL");
 241