linux/sound/soc/pxa/pxa2xx-i2s.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * pxa2xx-i2s.c  --  ALSA Soc Audio Layer
   4 *
   5 * Copyright 2005 Wolfson Microelectronics PLC.
   6 * Author: Liam Girdwood
   7 *         lrg@slimlogic.co.uk
   8 */
   9
  10#include <linux/init.h>
  11#include <linux/module.h>
  12#include <linux/device.h>
  13#include <linux/delay.h>
  14#include <linux/clk.h>
  15#include <linux/platform_device.h>
  16#include <linux/io.h>
  17#include <sound/core.h>
  18#include <sound/pcm.h>
  19#include <sound/initval.h>
  20#include <sound/soc.h>
  21#include <sound/pxa2xx-lib.h>
  22#include <sound/dmaengine_pcm.h>
  23
  24#include <mach/hardware.h>
  25#include <mach/audio.h>
  26
  27#include "pxa2xx-i2s.h"
  28
  29/*
  30 * I2S Controller Register and Bit Definitions
  31 */
  32#define SACR0           __REG(0x40400000)  /* Global Control Register */
  33#define SACR1           __REG(0x40400004)  /* Serial Audio I 2 S/MSB-Justified Control Register */
  34#define SASR0           __REG(0x4040000C)  /* Serial Audio I 2 S/MSB-Justified Interface and FIFO Status Register */
  35#define SAIMR           __REG(0x40400014)  /* Serial Audio Interrupt Mask Register */
  36#define SAICR           __REG(0x40400018)  /* Serial Audio Interrupt Clear Register */
  37#define SADIV           __REG(0x40400060)  /* Audio Clock Divider Register. */
  38#define SADR            __REG(0x40400080)  /* Serial Audio Data Register (TX and RX FIFO access Register). */
  39
  40#define SACR0_RFTH(x)   ((x) << 12)     /* Rx FIFO Interrupt or DMA Trigger Threshold */
  41#define SACR0_TFTH(x)   ((x) << 8)      /* Tx FIFO Interrupt or DMA Trigger Threshold */
  42#define SACR0_STRF      (1 << 5)        /* FIFO Select for EFWR Special Function */
  43#define SACR0_EFWR      (1 << 4)        /* Enable EFWR Function  */
  44#define SACR0_RST       (1 << 3)        /* FIFO, i2s Register Reset */
  45#define SACR0_BCKD      (1 << 2)        /* Bit Clock Direction */
  46#define SACR0_ENB       (1 << 0)        /* Enable I2S Link */
  47#define SACR1_ENLBF     (1 << 5)        /* Enable Loopback */
  48#define SACR1_DRPL      (1 << 4)        /* Disable Replaying Function */
  49#define SACR1_DREC      (1 << 3)        /* Disable Recording Function */
  50#define SACR1_AMSL      (1 << 0)        /* Specify Alternate Mode */
  51
  52#define SASR0_I2SOFF    (1 << 7)        /* Controller Status */
  53#define SASR0_ROR       (1 << 6)        /* Rx FIFO Overrun */
  54#define SASR0_TUR       (1 << 5)        /* Tx FIFO Underrun */
  55#define SASR0_RFS       (1 << 4)        /* Rx FIFO Service Request */
  56#define SASR0_TFS       (1 << 3)        /* Tx FIFO Service Request */
  57#define SASR0_BSY       (1 << 2)        /* I2S Busy */
  58#define SASR0_RNE       (1 << 1)        /* Rx FIFO Not Empty */
  59#define SASR0_TNF       (1 << 0)        /* Tx FIFO Not Empty */
  60
  61#define SAICR_ROR       (1 << 6)        /* Clear Rx FIFO Overrun Interrupt */
  62#define SAICR_TUR       (1 << 5)        /* Clear Tx FIFO Underrun Interrupt */
  63
  64#define SAIMR_ROR       (1 << 6)        /* Enable Rx FIFO Overrun Condition Interrupt */
  65#define SAIMR_TUR       (1 << 5)        /* Enable Tx FIFO Underrun Condition Interrupt */
  66#define SAIMR_RFS       (1 << 4)        /* Enable Rx FIFO Service Interrupt */
  67#define SAIMR_TFS       (1 << 3)        /* Enable Tx FIFO Service Interrupt */
  68
  69struct pxa_i2s_port {
  70        u32 sadiv;
  71        u32 sacr0;
  72        u32 sacr1;
  73        u32 saimr;
  74        int master;
  75        u32 fmt;
  76};
  77static struct pxa_i2s_port pxa_i2s;
  78static struct clk *clk_i2s;
  79static int clk_ena = 0;
  80
  81static struct snd_dmaengine_dai_dma_data pxa2xx_i2s_pcm_stereo_out = {
  82        .addr           = __PREG(SADR),
  83        .addr_width     = DMA_SLAVE_BUSWIDTH_4_BYTES,
  84        .chan_name      = "tx",
  85        .maxburst       = 32,
  86};
  87
  88static struct snd_dmaengine_dai_dma_data pxa2xx_i2s_pcm_stereo_in = {
  89        .addr           = __PREG(SADR),
  90        .addr_width     = DMA_SLAVE_BUSWIDTH_4_BYTES,
  91        .chan_name      = "rx",
  92        .maxburst       = 32,
  93};
  94
  95static int pxa2xx_i2s_startup(struct snd_pcm_substream *substream,
  96                              struct snd_soc_dai *dai)
  97{
  98        struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
  99        struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
 100
 101        if (IS_ERR(clk_i2s))
 102                return PTR_ERR(clk_i2s);
 103
 104        if (!snd_soc_dai_active(cpu_dai))
 105                SACR0 = 0;
 106
 107        return 0;
 108}
 109
 110/* wait for I2S controller to be ready */
 111static int pxa_i2s_wait(void)
 112{
 113        int i;
 114
 115        /* flush the Rx FIFO */
 116        for (i = 0; i < 16; i++)
 117                SADR;
 118        return 0;
 119}
 120
 121static int pxa2xx_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai,
 122                unsigned int fmt)
 123{
 124        /* interface format */
 125        switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
 126        case SND_SOC_DAIFMT_I2S:
 127                pxa_i2s.fmt = 0;
 128                break;
 129        case SND_SOC_DAIFMT_LEFT_J:
 130                pxa_i2s.fmt = SACR1_AMSL;
 131                break;
 132        }
 133
 134        switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
 135        case SND_SOC_DAIFMT_CBS_CFS:
 136                pxa_i2s.master = 1;
 137                break;
 138        case SND_SOC_DAIFMT_CBM_CFS:
 139                pxa_i2s.master = 0;
 140                break;
 141        default:
 142                break;
 143        }
 144        return 0;
 145}
 146
 147static int pxa2xx_i2s_set_dai_sysclk(struct snd_soc_dai *cpu_dai,
 148                int clk_id, unsigned int freq, int dir)
 149{
 150        if (clk_id != PXA2XX_I2S_SYSCLK)
 151                return -ENODEV;
 152
 153        return 0;
 154}
 155
 156static int pxa2xx_i2s_hw_params(struct snd_pcm_substream *substream,
 157                                struct snd_pcm_hw_params *params,
 158                                struct snd_soc_dai *dai)
 159{
 160        struct snd_dmaengine_dai_dma_data *dma_data;
 161
 162        if (WARN_ON(IS_ERR(clk_i2s)))
 163                return -EINVAL;
 164        clk_prepare_enable(clk_i2s);
 165        clk_ena = 1;
 166        pxa_i2s_wait();
 167
 168        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 169                dma_data = &pxa2xx_i2s_pcm_stereo_out;
 170        else
 171                dma_data = &pxa2xx_i2s_pcm_stereo_in;
 172
 173        snd_soc_dai_set_dma_data(dai, substream, dma_data);
 174
 175        /* is port used by another stream */
 176        if (!(SACR0 & SACR0_ENB)) {
 177                SACR0 = 0;
 178                if (pxa_i2s.master)
 179                        SACR0 |= SACR0_BCKD;
 180
 181                SACR0 |= SACR0_RFTH(14) | SACR0_TFTH(1);
 182                SACR1 |= pxa_i2s.fmt;
 183        }
 184        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 185                SAIMR |= SAIMR_TFS;
 186        else
 187                SAIMR |= SAIMR_RFS;
 188
 189        switch (params_rate(params)) {
 190        case 8000:
 191                SADIV = 0x48;
 192                break;
 193        case 11025:
 194                SADIV = 0x34;
 195                break;
 196        case 16000:
 197                SADIV = 0x24;
 198                break;
 199        case 22050:
 200                SADIV = 0x1a;
 201                break;
 202        case 44100:
 203                SADIV = 0xd;
 204                break;
 205        case 48000:
 206                SADIV = 0xc;
 207                break;
 208        case 96000: /* not in manual and possibly slightly inaccurate */
 209                SADIV = 0x6;
 210                break;
 211        }
 212
 213        return 0;
 214}
 215
 216static int pxa2xx_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
 217                              struct snd_soc_dai *dai)
 218{
 219        int ret = 0;
 220
 221        switch (cmd) {
 222        case SNDRV_PCM_TRIGGER_START:
 223                if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 224                        SACR1 &= ~SACR1_DRPL;
 225                else
 226                        SACR1 &= ~SACR1_DREC;
 227                SACR0 |= SACR0_ENB;
 228                break;
 229        case SNDRV_PCM_TRIGGER_RESUME:
 230        case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 231        case SNDRV_PCM_TRIGGER_STOP:
 232        case SNDRV_PCM_TRIGGER_SUSPEND:
 233        case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 234                break;
 235        default:
 236                ret = -EINVAL;
 237        }
 238
 239        return ret;
 240}
 241
 242static void pxa2xx_i2s_shutdown(struct snd_pcm_substream *substream,
 243                                struct snd_soc_dai *dai)
 244{
 245        if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 246                SACR1 |= SACR1_DRPL;
 247                SAIMR &= ~SAIMR_TFS;
 248        } else {
 249                SACR1 |= SACR1_DREC;
 250                SAIMR &= ~SAIMR_RFS;
 251        }
 252
 253        if ((SACR1 & (SACR1_DREC | SACR1_DRPL)) == (SACR1_DREC | SACR1_DRPL)) {
 254                SACR0 &= ~SACR0_ENB;
 255                pxa_i2s_wait();
 256                if (clk_ena) {
 257                        clk_disable_unprepare(clk_i2s);
 258                        clk_ena = 0;
 259                }
 260        }
 261}
 262
 263#ifdef CONFIG_PM
 264static int pxa2xx_soc_pcm_suspend(struct snd_soc_component *component)
 265{
 266        /* store registers */
 267        pxa_i2s.sacr0 = SACR0;
 268        pxa_i2s.sacr1 = SACR1;
 269        pxa_i2s.saimr = SAIMR;
 270        pxa_i2s.sadiv = SADIV;
 271
 272        /* deactivate link */
 273        SACR0 &= ~SACR0_ENB;
 274        pxa_i2s_wait();
 275        return 0;
 276}
 277
 278static int pxa2xx_soc_pcm_resume(struct snd_soc_component *component)
 279{
 280        pxa_i2s_wait();
 281
 282        SACR0 = pxa_i2s.sacr0 & ~SACR0_ENB;
 283        SACR1 = pxa_i2s.sacr1;
 284        SAIMR = pxa_i2s.saimr;
 285        SADIV = pxa_i2s.sadiv;
 286
 287        SACR0 = pxa_i2s.sacr0;
 288
 289        return 0;
 290}
 291
 292#else
 293#define pxa2xx_soc_pcm_suspend  NULL
 294#define pxa2xx_soc_pcm_resume   NULL
 295#endif
 296
 297static int pxa2xx_i2s_probe(struct snd_soc_dai *dai)
 298{
 299        clk_i2s = clk_get(dai->dev, "I2SCLK");
 300        if (IS_ERR(clk_i2s))
 301                return PTR_ERR(clk_i2s);
 302
 303        /*
 304         * PXA Developer's Manual:
 305         * If SACR0[ENB] is toggled in the middle of a normal operation,
 306         * the SACR0[RST] bit must also be set and cleared to reset all
 307         * I2S controller registers.
 308         */
 309        SACR0 = SACR0_RST;
 310        SACR0 = 0;
 311        /* Make sure RPL and REC are disabled */
 312        SACR1 = SACR1_DRPL | SACR1_DREC;
 313        /* Along with FIFO servicing */
 314        SAIMR &= ~(SAIMR_RFS | SAIMR_TFS);
 315
 316        snd_soc_dai_init_dma_data(dai, &pxa2xx_i2s_pcm_stereo_out,
 317                &pxa2xx_i2s_pcm_stereo_in);
 318
 319        return 0;
 320}
 321
 322static int  pxa2xx_i2s_remove(struct snd_soc_dai *dai)
 323{
 324        clk_put(clk_i2s);
 325        clk_i2s = ERR_PTR(-ENOENT);
 326        return 0;
 327}
 328
 329#define PXA2XX_I2S_RATES (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 |\
 330                SNDRV_PCM_RATE_16000 | SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_44100 | \
 331                SNDRV_PCM_RATE_48000 | SNDRV_PCM_RATE_96000)
 332
 333static const struct snd_soc_dai_ops pxa_i2s_dai_ops = {
 334        .startup        = pxa2xx_i2s_startup,
 335        .shutdown       = pxa2xx_i2s_shutdown,
 336        .trigger        = pxa2xx_i2s_trigger,
 337        .hw_params      = pxa2xx_i2s_hw_params,
 338        .set_fmt        = pxa2xx_i2s_set_dai_fmt,
 339        .set_sysclk     = pxa2xx_i2s_set_dai_sysclk,
 340};
 341
 342static struct snd_soc_dai_driver pxa_i2s_dai = {
 343        .probe = pxa2xx_i2s_probe,
 344        .remove = pxa2xx_i2s_remove,
 345        .playback = {
 346                .channels_min = 2,
 347                .channels_max = 2,
 348                .rates = PXA2XX_I2S_RATES,
 349                .formats = SNDRV_PCM_FMTBIT_S16_LE,},
 350        .capture = {
 351                .channels_min = 2,
 352                .channels_max = 2,
 353                .rates = PXA2XX_I2S_RATES,
 354                .formats = SNDRV_PCM_FMTBIT_S16_LE,},
 355        .ops = &pxa_i2s_dai_ops,
 356        .symmetric_rate = 1,
 357};
 358
 359static const struct snd_soc_component_driver pxa_i2s_component = {
 360        .name           = "pxa-i2s",
 361        .pcm_construct  = pxa2xx_soc_pcm_new,
 362        .open           = pxa2xx_soc_pcm_open,
 363        .close          = pxa2xx_soc_pcm_close,
 364        .hw_params      = pxa2xx_soc_pcm_hw_params,
 365        .prepare        = pxa2xx_soc_pcm_prepare,
 366        .trigger        = pxa2xx_soc_pcm_trigger,
 367        .pointer        = pxa2xx_soc_pcm_pointer,
 368        .suspend        = pxa2xx_soc_pcm_suspend,
 369        .resume         = pxa2xx_soc_pcm_resume,
 370};
 371
 372static int pxa2xx_i2s_drv_probe(struct platform_device *pdev)
 373{
 374        return devm_snd_soc_register_component(&pdev->dev, &pxa_i2s_component,
 375                                               &pxa_i2s_dai, 1);
 376}
 377
 378static struct platform_driver pxa2xx_i2s_driver = {
 379        .probe = pxa2xx_i2s_drv_probe,
 380
 381        .driver = {
 382                .name = "pxa2xx-i2s",
 383        },
 384};
 385
 386static int __init pxa2xx_i2s_init(void)
 387{
 388        clk_i2s = ERR_PTR(-ENOENT);
 389        return platform_driver_register(&pxa2xx_i2s_driver);
 390}
 391
 392static void __exit pxa2xx_i2s_exit(void)
 393{
 394        platform_driver_unregister(&pxa2xx_i2s_driver);
 395}
 396
 397module_init(pxa2xx_i2s_init);
 398module_exit(pxa2xx_i2s_exit);
 399
 400/* Module information */
 401MODULE_AUTHOR("Liam Girdwood, lrg@slimlogic.co.uk");
 402MODULE_DESCRIPTION("pxa2xx I2S SoC Interface");
 403MODULE_LICENSE("GPL");
 404MODULE_ALIAS("platform:pxa2xx-i2s");
 405