sound/soc/fsl/mpc5200_psc_i2s.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 //
   3 // Freescale MPC5200 PSC in I2S mode
   4 // ALSA SoC Digital Audio Interface (DAI) driver
   5 //
   6 // Copyright (C) 2008 Secret Lab Technologies Ltd.
   7 // Copyright (C) 2009 Jon Smirl, Digispeaker
   8
   9 #include <linux/module.h>
  10 #include <linux/of.h>
  11
  12 #include <sound/pcm.h>
  13 #include <sound/pcm_params.h>
  14 #include <sound/soc.h>
  15
  16 #include <asm/mpc52xx_psc.h>
  17
  18 #include "mpc5200_dma.h"
  19
  20 /**
  21  * PSC_I2S_RATES: sample rates supported by the I2S
  22  *
  23  * This driver currently only supports the PSC running in I2S slave mode,
  24  * which means the codec determines the sample rate.  Therefore, we tell
  25  * ALSA that we support all rates and let the codec driver decide what rates
  26  * are really supported.
  27  */
  28 #define PSC_I2S_RATES SNDRV_PCM_RATE_CONTINUOUS
  29
  30 /**
  31  * PSC_I2S_FORMATS: audio formats supported by the PSC I2S mode
  32  */
  33 #define PSC_I2S_FORMATS (SNDRV_PCM_FMTBIT_S8 | SNDRV_PCM_FMTBIT_S16_BE | \
  34                          SNDRV_PCM_FMTBIT_S24_BE | SNDRV_PCM_FMTBIT_S32_BE)
  35
  36 static int psc_i2s_hw_params(struct snd_pcm_substream *substream,
  37                                  struct snd_pcm_hw_params *params,
  38                                  struct snd_soc_dai *dai)
  39 {
  40         struct snd_soc_pcm_runtime *rtd = snd_soc_substream_to_rtd(substream);
  41         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(snd_soc_rtd_to_cpu(rtd, 0));
  42         u32 mode;
  43
  44         dev_dbg(psc_dma->dev, "%s(substream=%p) p_size=%i p_bytes=%i"
  45                 " periods=%i buffer_size=%i  buffer_bytes=%i\n",
  46                 __func__, substream, params_period_size(params),
  47                 params_period_bytes(params), params_periods(params),
  48                 params_buffer_size(params), params_buffer_bytes(params));
  49
  50         switch (params_format(params)) {
  51         case SNDRV_PCM_FORMAT_S8:
  52                 mode = MPC52xx_PSC_SICR_SIM_CODEC_8;
  53                 break;
  54         case SNDRV_PCM_FORMAT_S16_BE:
  55                 mode = MPC52xx_PSC_SICR_SIM_CODEC_16;
  56                 break;
  57         case SNDRV_PCM_FORMAT_S24_BE:
  58                 mode = MPC52xx_PSC_SICR_SIM_CODEC_24;
  59                 break;
  60         case SNDRV_PCM_FORMAT_S32_BE:
  61                 mode = MPC52xx_PSC_SICR_SIM_CODEC_32;
  62                 break;
  63         default:
  64                 dev_dbg(psc_dma->dev, "invalid format\n");
  65                 return -EINVAL;
  66         }
  67         out_be32(&psc_dma->psc_regs->sicr, psc_dma->sicr | mode);
  68
  69         return 0;
  70 }
  71
  72 /**
  73  * psc_i2s_set_sysclk: set the clock frequency and direction
  74  *
  75  * This function is called by the machine driver to tell us what the clock
  76  * frequency and direction are.
  77  *
  78  * Currently, we only support operating as a clock slave (SND_SOC_CLOCK_IN),
  79  * and we don't care about the frequency.  Return an error if the direction
  80  * is not SND_SOC_CLOCK_IN.
  81  *
  82  * @clk_id: reserved, should be zero
  83  * @freq: the frequency of the given clock ID, currently ignored
  84  * @dir: SND_SOC_CLOCK_IN (clock slave) or SND_SOC_CLOCK_OUT (clock master)
  85  */
  86 static int psc_i2s_set_sysclk(struct snd_soc_dai *cpu_dai,
  87                               int clk_id, unsigned int freq, int dir)
  88 {
  89         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
  90         dev_dbg(psc_dma->dev, "psc_i2s_set_sysclk(cpu_dai=%p, dir=%i)\n",
  91                                 cpu_dai, dir);
  92         return (dir == SND_SOC_CLOCK_IN) ? 0 : -EINVAL;
  93 }
  94
  95 /**
  96  * psc_i2s_set_fmt: set the serial format.
  97  *
  98  * This function is called by the machine driver to tell us what serial
  99  * format to use.
 100  *
 101  * This driver only supports I2S mode.  Return an error if the format is
 102  * not SND_SOC_DAIFMT_I2S.
 103  *
 104  * @format: one of SND_SOC_DAIFMT_xxx
 105  */
 106 static int psc_i2s_set_fmt(struct snd_soc_dai *cpu_dai, unsigned int format)
 107 {
 108         struct psc_dma *psc_dma = snd_soc_dai_get_drvdata(cpu_dai);
 109         dev_dbg(psc_dma->dev, "psc_i2s_set_fmt(cpu_dai=%p, format=%i)\n",
 110                                 cpu_dai, format);
 111         return (format == SND_SOC_DAIFMT_I2S) ? 0 : -EINVAL;
 112 }
 113
 114 /* ---------------------------------------------------------------------
 115  * ALSA SoC Bindings
 116  *
 117  * - Digital Audio Interface (DAI) template
 118  * - create/destroy dai hooks
 119  */
 120
 121 /**
 122  * psc_i2s_dai_template: template CPU Digital Audio Interface
 123  */
 124 static const struct snd_soc_dai_ops psc_i2s_dai_ops = {
 125         .hw_params      = psc_i2s_hw_params,
 126         .set_sysclk     = psc_i2s_set_sysclk,
 127         .set_fmt        = psc_i2s_set_fmt,
 128 };
 129
 130 static struct snd_soc_dai_driver psc_i2s_dai[] = {{
 131         .name = "mpc5200-psc-i2s.0",
 132         .playback = {
 133                 .stream_name = "I2S Playback",
 134                 .channels_min = 2,
 135                 .channels_max = 2,
 136                 .rates = PSC_I2S_RATES,
 137                 .formats = PSC_I2S_FORMATS,
 138         },
 139         .capture = {
 140                 .stream_name = "I2S Capture",
 141                 .channels_min = 2,
 142                 .channels_max = 2,
 143                 .rates = PSC_I2S_RATES,
 144                 .formats = PSC_I2S_FORMATS,
 145         },
 146         .ops = &psc_i2s_dai_ops,
 147 } };
 148
 149 static const struct snd_soc_component_driver psc_i2s_component = {
 150         .name                   = "mpc5200-i2s",
 151         .legacy_dai_naming      = 1,
 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_property_present(op->dev.of_node, "codec-handle"))
 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 void psc_i2s_of_remove(struct platform_device *op)
 213 {
 214         mpc5200_audio_dma_destroy(op);
 215         snd_soc_unregister_component(&op->dev);
 216 }
 217
 218 /* Match table for of_platform binding */
 219 static const struct of_device_id psc_i2s_match[] = {
 220         { .compatible = "fsl,mpc5200-psc-i2s", },
 221         { .compatible = "fsl,mpc5200b-psc-i2s", },
 222         {}
 223 };
 224 MODULE_DEVICE_TABLE(of, psc_i2s_match);
 225
 226 static struct platform_driver psc_i2s_driver = {
 227         .probe = psc_i2s_of_probe,
 228         .remove = psc_i2s_of_remove,
 229         .driver = {
 230                 .name = "mpc5200-psc-i2s",
 231                 .of_match_table = psc_i2s_match,
 232         },
 233 };
 234
 235 module_platform_driver(psc_i2s_driver);
 236
 237 MODULE_AUTHOR("Grant Likely <grant.likely@secretlab.ca>");
 238 MODULE_DESCRIPTION("Freescale MPC5200 PSC in I2S mode ASoC Driver");
 239 MODULE_LICENSE("GPL");
 240