LXR linux/sound/soc/au1x/psc-ac97.c

   1/*
   2 * Au12x0/Au1550 PSC ALSA ASoC audio support.
   3 *
   4 * (c) 2007-2009 MSC Vertriebsges.m.b.H.,
   5 *      Manuel Lauss <manuel.lauss@gmail.com>
   6 *
   7 * This program is free software; you can redistribute it and/or modify
   8 * it under the terms of the GNU General Public License version 2 as
   9 * published by the Free Software Foundation.
  10 *
  11 * Au1xxx-PSC AC97 glue.
  12 *
  13 */
  14
  15#include <linux/init.h>
  16#include <linux/module.h>
  17#include <linux/slab.h>
  18#include <linux/device.h>
  19#include <linux/delay.h>
  20#include <linux/mutex.h>
  21#include <linux/suspend.h>
  22#include <sound/core.h>
  23#include <sound/pcm.h>
  24#include <sound/initval.h>
  25#include <sound/soc.h>
  26#include <asm/mach-au1x00/au1000.h>
  27#include <asm/mach-au1x00/au1xxx_psc.h>
  28
  29#include "psc.h"
  30
  31/* how often to retry failed codec register reads/writes */
  32#define AC97_RW_RETRIES 5
  33
  34#define AC97_DIR        \
  35        (SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
  36
  37#define AC97_RATES      \
  38        SNDRV_PCM_RATE_8000_48000
  39
  40#define AC97_FMTS       \
  41        (SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3BE)
  42
  43#define AC97PCR_START(stype)    \
  44        ((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TS : PSC_AC97PCR_RS)
  45#define AC97PCR_STOP(stype)     \
  46        ((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TP : PSC_AC97PCR_RP)
  47#define AC97PCR_CLRFIFO(stype)  \
  48        ((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TC : PSC_AC97PCR_RC)
  49
  50#define AC97STAT_BUSY(stype)    \
  51        ((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97STAT_TB : PSC_AC97STAT_RB)
  52
  53/* instance data. There can be only one, MacLeod!!!! */
  54static struct au1xpsc_audio_data *au1xpsc_ac97_workdata;
  55
  56#if 0
  57
  58/* this could theoretically work, but ac97->bus->card->private_data can be NULL
  59 * when snd_ac97_mixer() is called; I don't know if the rest further down the
  60 * chain are always valid either.
  61 */
  62static inline struct au1xpsc_audio_data *ac97_to_pscdata(struct snd_ac97 *x)
  63{
  64        struct snd_soc_card *c = x->bus->card->private_data;
  65        return snd_soc_dai_get_drvdata(c->rtd->cpu_dai);
  66}
  67
  68#else
  69
  70#define ac97_to_pscdata(x)      au1xpsc_ac97_workdata
  71
  72#endif
  73
  74/* AC97 controller reads codec register */
  75static unsigned short au1xpsc_ac97_read(struct snd_ac97 *ac97,
  76                                        unsigned short reg)
  77{
  78        struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
  79        unsigned short retry, tmo;
  80        unsigned long data;
  81
  82        __raw_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
  83        wmb(); /* drain writebuffer */
  84
  85        retry = AC97_RW_RETRIES;
  86        do {
  87                mutex_lock(&pscdata->lock);
  88
  89                __raw_writel(PSC_AC97CDC_RD | PSC_AC97CDC_INDX(reg),
  90                          AC97_CDC(pscdata));
  91                wmb(); /* drain writebuffer */
  92
  93                tmo = 20;
  94                do {
  95                        udelay(21);
  96                        if (__raw_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD)
  97                                break;
  98                } while (--tmo);
  99
 100                data = __raw_readl(AC97_CDC(pscdata));
 101
 102                __raw_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
 103                wmb(); /* drain writebuffer */
 104
 105                mutex_unlock(&pscdata->lock);
 106
 107                if (reg != ((data >> 16) & 0x7f))
 108                        tmo = 1;        /* wrong register, try again */
 109
 110        } while (--retry && !tmo);
 111
 112        return retry ? data & 0xffff : 0xffff;
 113}
 114
 115/* AC97 controller writes to codec register */
 116static void au1xpsc_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
 117                                unsigned short val)
 118{
 119        struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
 120        unsigned int tmo, retry;
 121
 122        __raw_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
 123        wmb(); /* drain writebuffer */
 124
 125        retry = AC97_RW_RETRIES;
 126        do {
 127                mutex_lock(&pscdata->lock);
 128
 129                __raw_writel(PSC_AC97CDC_INDX(reg) | (val & 0xffff),
 130                          AC97_CDC(pscdata));
 131                wmb(); /* drain writebuffer */
 132
 133                tmo = 20;
 134                do {
 135                        udelay(21);
 136                        if (__raw_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD)
 137                                break;
 138                } while (--tmo);
 139
 140                __raw_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
 141                wmb(); /* drain writebuffer */
 142
 143                mutex_unlock(&pscdata->lock);
 144        } while (--retry && !tmo);
 145}
 146
 147/* AC97 controller asserts a warm reset */
 148static void au1xpsc_ac97_warm_reset(struct snd_ac97 *ac97)
 149{
 150        struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
 151
 152        __raw_writel(PSC_AC97RST_SNC, AC97_RST(pscdata));
 153        wmb(); /* drain writebuffer */
 154        msleep(10);
 155        __raw_writel(0, AC97_RST(pscdata));
 156        wmb(); /* drain writebuffer */
 157}
 158
 159static void au1xpsc_ac97_cold_reset(struct snd_ac97 *ac97)
 160{
 161        struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
 162        int i;
 163
 164        /* disable PSC during cold reset */
 165        __raw_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
 166        wmb(); /* drain writebuffer */
 167        __raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(pscdata));
 168        wmb(); /* drain writebuffer */
 169
 170        /* issue cold reset */
 171        __raw_writel(PSC_AC97RST_RST, AC97_RST(pscdata));
 172        wmb(); /* drain writebuffer */
 173        msleep(500);
 174        __raw_writel(0, AC97_RST(pscdata));
 175        wmb(); /* drain writebuffer */
 176
 177        /* enable PSC */
 178        __raw_writel(PSC_CTRL_ENABLE, PSC_CTRL(pscdata));
 179        wmb(); /* drain writebuffer */
 180
 181        /* wait for PSC to indicate it's ready */
 182        i = 1000;
 183        while (!((__raw_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_SR)) && (--i))
 184                msleep(1);
 185
 186        if (i == 0) {
 187                printk(KERN_ERR "au1xpsc-ac97: PSC not ready!\n");
 188                return;
 189        }
 190
 191        /* enable the ac97 function */
 192        __raw_writel(pscdata->cfg | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
 193        wmb(); /* drain writebuffer */
 194
 195        /* wait for AC97 core to become ready */
 196        i = 1000;
 197        while (!((__raw_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)) && (--i))
 198                msleep(1);
 199        if (i == 0)
 200                printk(KERN_ERR "au1xpsc-ac97: AC97 ctrl not ready\n");
 201}
 202
 203/* AC97 controller operations */
 204static struct snd_ac97_bus_ops psc_ac97_ops = {
 205        .read           = au1xpsc_ac97_read,
 206        .write          = au1xpsc_ac97_write,
 207        .reset          = au1xpsc_ac97_cold_reset,
 208        .warm_reset     = au1xpsc_ac97_warm_reset,
 209};
 210
 211static int au1xpsc_ac97_hw_params(struct snd_pcm_substream *substream,
 212                                  struct snd_pcm_hw_params *params,
 213                                  struct snd_soc_dai *dai)
 214{
 215        struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
 216        unsigned long r, ro, stat;
 217        int chans, t, stype = substream->stream;
 218
 219        chans = params_channels(params);
 220
 221        r = ro = __raw_readl(AC97_CFG(pscdata));
 222        stat = __raw_readl(AC97_STAT(pscdata));
 223
 224        /* already active? */
 225        if (stat & (PSC_AC97STAT_TB | PSC_AC97STAT_RB)) {
 226                /* reject parameters not currently set up */
 227                if ((PSC_AC97CFG_GET_LEN(r) != params->msbits) ||
 228                    (pscdata->rate != params_rate(params)))
 229                        return -EINVAL;
 230        } else {
 231
 232                /* set sample bitdepth: REG[24:21]=(BITS-2)/2 */
 233                r &= ~PSC_AC97CFG_LEN_MASK;
 234                r |= PSC_AC97CFG_SET_LEN(params->msbits);
 235
 236                /* channels: enable slots for front L/R channel */
 237                if (stype == SNDRV_PCM_STREAM_PLAYBACK) {
 238                        r &= ~PSC_AC97CFG_TXSLOT_MASK;
 239                        r |= PSC_AC97CFG_TXSLOT_ENA(3);
 240                        r |= PSC_AC97CFG_TXSLOT_ENA(4);
 241                } else {
 242                        r &= ~PSC_AC97CFG_RXSLOT_MASK;
 243                        r |= PSC_AC97CFG_RXSLOT_ENA(3);
 244                        r |= PSC_AC97CFG_RXSLOT_ENA(4);
 245                }
 246
 247                /* do we need to poke the hardware? */
 248                if (!(r ^ ro))
 249                        goto out;
 250
 251                /* ac97 engine is about to be disabled */
 252                mutex_lock(&pscdata->lock);
 253
 254                /* disable AC97 device controller first... */
 255                __raw_writel(r & ~PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
 256                wmb(); /* drain writebuffer */
 257
 258                /* ...wait for it... */
 259                t = 100;
 260                while ((__raw_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR) && --t)
 261                        msleep(1);
 262
 263                if (!t)
 264                        printk(KERN_ERR "PSC-AC97: can't disable!\n");
 265
 266                /* ...write config... */
 267                __raw_writel(r, AC97_CFG(pscdata));
 268                wmb(); /* drain writebuffer */
 269
 270                /* ...enable the AC97 controller again... */
 271                __raw_writel(r | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
 272                wmb(); /* drain writebuffer */
 273
 274                /* ...and wait for ready bit */
 275                t = 100;
 276                while ((!(__raw_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)) && --t)
 277                        msleep(1);
 278
 279                if (!t)
 280                        printk(KERN_ERR "PSC-AC97: can't enable!\n");
 281
 282                mutex_unlock(&pscdata->lock);
 283
 284                pscdata->cfg = r;
 285                pscdata->rate = params_rate(params);
 286        }
 287
 288out:
 289        return 0;
 290}
 291
 292static int au1xpsc_ac97_trigger(struct snd_pcm_substream *substream,
 293                                int cmd, struct snd_soc_dai *dai)
 294{
 295        struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
 296        int ret, stype = substream->stream;
 297
 298        ret = 0;
 299
 300        switch (cmd) {
 301        case SNDRV_PCM_TRIGGER_START:
 302        case SNDRV_PCM_TRIGGER_RESUME:
 303                __raw_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
 304                wmb(); /* drain writebuffer */
 305                __raw_writel(AC97PCR_START(stype), AC97_PCR(pscdata));
 306                wmb(); /* drain writebuffer */
 307                break;
 308        case SNDRV_PCM_TRIGGER_STOP:
 309        case SNDRV_PCM_TRIGGER_SUSPEND:
 310                __raw_writel(AC97PCR_STOP(stype), AC97_PCR(pscdata));
 311                wmb(); /* drain writebuffer */
 312
 313                while (__raw_readl(AC97_STAT(pscdata)) & AC97STAT_BUSY(stype))
 314                        asm volatile ("nop");
 315
 316                __raw_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
 317                wmb(); /* drain writebuffer */
 318
 319                break;
 320        default:
 321                ret = -EINVAL;
 322        }
 323        return ret;
 324}
 325
 326static int au1xpsc_ac97_startup(struct snd_pcm_substream *substream,
 327                                struct snd_soc_dai *dai)
 328{
 329        struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
 330        snd_soc_dai_set_dma_data(dai, substream, &pscdata->dmaids[0]);
 331        return 0;
 332}
 333
 334static int au1xpsc_ac97_probe(struct snd_soc_dai *dai)
 335{
 336        return au1xpsc_ac97_workdata ? 0 : -ENODEV;
 337}
 338
 339static const struct snd_soc_dai_ops au1xpsc_ac97_dai_ops = {
 340        .startup        = au1xpsc_ac97_startup,
 341        .trigger        = au1xpsc_ac97_trigger,
 342        .hw_params      = au1xpsc_ac97_hw_params,
 343};
 344
 345static const struct snd_soc_dai_driver au1xpsc_ac97_dai_template = {
 346        .bus_control            = true,
 347        .probe                  = au1xpsc_ac97_probe,
 348        .playback = {
 349                .rates          = AC97_RATES,
 350                .formats        = AC97_FMTS,
 351                .channels_min   = 2,
 352                .channels_max   = 2,
 353        },
 354        .capture = {
 355                .rates          = AC97_RATES,
 356                .formats        = AC97_FMTS,
 357                .channels_min   = 2,
 358                .channels_max   = 2,
 359        },
 360        .ops = &au1xpsc_ac97_dai_ops,
 361};
 362
 363static const struct snd_soc_component_driver au1xpsc_ac97_component = {
 364        .name           = "au1xpsc-ac97",
 365};
 366
 367static int au1xpsc_ac97_drvprobe(struct platform_device *pdev)
 368{
 369        int ret;
 370        struct resource *iores, *dmares;
 371        unsigned long sel;
 372        struct au1xpsc_audio_data *wd;
 373
 374        wd = devm_kzalloc(&pdev->dev, sizeof(struct au1xpsc_audio_data),
 375                          GFP_KERNEL);
 376        if (!wd)
 377                return -ENOMEM;
 378
 379        mutex_init(&wd->lock);
 380
 381        iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 382        wd->mmio = devm_ioremap_resource(&pdev->dev, iores);
 383        if (IS_ERR(wd->mmio))
 384                return PTR_ERR(wd->mmio);
 385
 386        dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
 387        if (!dmares)
 388                return -EBUSY;
 389        wd->dmaids[SNDRV_PCM_STREAM_PLAYBACK] = dmares->start;
 390
 391        dmares = platform_get_resource(pdev, IORESOURCE_DMA, 1);
 392        if (!dmares)
 393                return -EBUSY;
 394        wd->dmaids[SNDRV_PCM_STREAM_CAPTURE] = dmares->start;
 395
 396        /* configuration: max dma trigger threshold, enable ac97 */
 397        wd->cfg = PSC_AC97CFG_RT_FIFO8 | PSC_AC97CFG_TT_FIFO8 |
 398                  PSC_AC97CFG_DE_ENABLE;
 399
 400        /* preserve PSC clock source set up by platform  */
 401        sel = __raw_readl(PSC_SEL(wd)) & PSC_SEL_CLK_MASK;
 402        __raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
 403        wmb(); /* drain writebuffer */
 404        __raw_writel(0, PSC_SEL(wd));
 405        wmb(); /* drain writebuffer */
 406        __raw_writel(PSC_SEL_PS_AC97MODE | sel, PSC_SEL(wd));
 407        wmb(); /* drain writebuffer */
 408
 409        /* name the DAI like this device instance ("au1xpsc-ac97.PSCINDEX") */
 410        memcpy(&wd->dai_drv, &au1xpsc_ac97_dai_template,
 411               sizeof(struct snd_soc_dai_driver));
 412        wd->dai_drv.name = dev_name(&pdev->dev);
 413
 414        platform_set_drvdata(pdev, wd);
 415
 416        ret = snd_soc_set_ac97_ops(&psc_ac97_ops);
 417        if (ret)
 418                return ret;
 419
 420        ret = snd_soc_register_component(&pdev->dev, &au1xpsc_ac97_component,
 421                                         &wd->dai_drv, 1);
 422        if (ret)
 423                return ret;
 424
 425        au1xpsc_ac97_workdata = wd;
 426        return 0;
 427}
 428
 429static int au1xpsc_ac97_drvremove(struct platform_device *pdev)
 430{
 431        struct au1xpsc_audio_data *wd = platform_get_drvdata(pdev);
 432
 433        snd_soc_unregister_component(&pdev->dev);
 434
 435        /* disable PSC completely */
 436        __raw_writel(0, AC97_CFG(wd));
 437        wmb(); /* drain writebuffer */
 438        __raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
 439        wmb(); /* drain writebuffer */
 440
 441        au1xpsc_ac97_workdata = NULL;   /* MDEV */
 442
 443        return 0;
 444}
 445
 446#ifdef CONFIG_PM
 447static int au1xpsc_ac97_drvsuspend(struct device *dev)
 448{
 449        struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
 450
 451        /* save interesting registers and disable PSC */
 452        wd->pm[0] = __raw_readl(PSC_SEL(wd));
 453
 454        __raw_writel(0, AC97_CFG(wd));
 455        wmb(); /* drain writebuffer */
 456        __raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
 457        wmb(); /* drain writebuffer */
 458
 459        return 0;
 460}
 461
 462static int au1xpsc_ac97_drvresume(struct device *dev)
 463{
 464        struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
 465
 466        /* restore PSC clock config */
 467        __raw_writel(wd->pm[0] | PSC_SEL_PS_AC97MODE, PSC_SEL(wd));
 468        wmb(); /* drain writebuffer */
 469
 470        /* after this point the ac97 core will cold-reset the codec.
 471         * During cold-reset the PSC is reinitialized and the last
 472         * configuration set up in hw_params() is restored.
 473         */
 474        return 0;
 475}
 476
 477static struct dev_pm_ops au1xpscac97_pmops = {
 478        .suspend        = au1xpsc_ac97_drvsuspend,
 479        .resume         = au1xpsc_ac97_drvresume,
 480};
 481
 482#define AU1XPSCAC97_PMOPS &au1xpscac97_pmops
 483
 484#else
 485
 486#define AU1XPSCAC97_PMOPS NULL
 487
 488#endif
 489
 490static struct platform_driver au1xpsc_ac97_driver = {
 491        .driver = {
 492                .name   = "au1xpsc_ac97",
 493                .pm     = AU1XPSCAC97_PMOPS,
 494        },
 495        .probe          = au1xpsc_ac97_drvprobe,
 496        .remove         = au1xpsc_ac97_drvremove,
 497};
 498
 499module_platform_driver(au1xpsc_ac97_driver);
 500
 501MODULE_LICENSE("GPL");
 502MODULE_DESCRIPTION("Au12x0/Au1550 PSC AC97 ALSA ASoC audio driver");
 503MODULE_AUTHOR("Manuel Lauss");
 504
 505