sound/soc/ep93xx/ep93xx-ac97.c

   1 /*
   2  * ASoC driver for Cirrus Logic EP93xx AC97 controller.
   3  *
   4  * Copyright (c) 2010 Mika Westerberg
   5  *
   6  * Based on s3c-ac97 ASoC driver by Jaswinder Singh.
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/delay.h>
  14 #include <linux/io.h>
  15 #include <linux/init.h>
  16 #include <linux/module.h>
  17 #include <linux/platform_device.h>
  18 #include <linux/slab.h>
  19
  20 #include <sound/core.h>
  21 #include <sound/ac97_codec.h>
  22 #include <sound/soc.h>
  23
  24 #include <mach/dma.h>
  25 #include "ep93xx-pcm.h"
  26
  27 /*
  28  * Per channel (1-4) registers.
  29  */
  30 #define AC97CH(n)               (((n) - 1) * 0x20)
  31
  32 #define AC97DR(n)               (AC97CH(n) + 0x0000)
  33
  34 #define AC97RXCR(n)             (AC97CH(n) + 0x0004)
  35 #define AC97RXCR_REN            BIT(0)
  36 #define AC97RXCR_RX3            BIT(3)
  37 #define AC97RXCR_RX4            BIT(4)
  38 #define AC97RXCR_CM             BIT(15)
  39
  40 #define AC97TXCR(n)             (AC97CH(n) + 0x0008)
  41 #define AC97TXCR_TEN            BIT(0)
  42 #define AC97TXCR_TX3            BIT(3)
  43 #define AC97TXCR_TX4            BIT(4)
  44 #define AC97TXCR_CM             BIT(15)
  45
  46 #define AC97SR(n)               (AC97CH(n) + 0x000c)
  47 #define AC97SR_TXFE             BIT(1)
  48 #define AC97SR_TXUE             BIT(6)
  49
  50 #define AC97RISR(n)             (AC97CH(n) + 0x0010)
  51 #define AC97ISR(n)              (AC97CH(n) + 0x0014)
  52 #define AC97IE(n)               (AC97CH(n) + 0x0018)
  53
  54 /*
  55  * Global AC97 controller registers.
  56  */
  57 #define AC97S1DATA              0x0080
  58 #define AC97S2DATA              0x0084
  59 #define AC97S12DATA             0x0088
  60
  61 #define AC97RGIS                0x008c
  62 #define AC97GIS                 0x0090
  63 #define AC97IM                  0x0094
  64 /*
  65  * Common bits for RGIS, GIS and IM registers.
  66  */
  67 #define AC97_SLOT2RXVALID       BIT(1)
  68 #define AC97_CODECREADY         BIT(5)
  69 #define AC97_SLOT2TXCOMPLETE    BIT(6)
  70
  71 #define AC97EOI                 0x0098
  72 #define AC97EOI_WINT            BIT(0)
  73 #define AC97EOI_CODECREADY      BIT(1)
  74
  75 #define AC97GCR                 0x009c
  76 #define AC97GCR_AC97IFE         BIT(0)
  77
  78 #define AC97RESET               0x00a0
  79 #define AC97RESET_TIMEDRESET    BIT(0)
  80
  81 #define AC97SYNC                0x00a4
  82 #define AC97SYNC_TIMEDSYNC      BIT(0)
  83
  84 #define AC97_TIMEOUT            msecs_to_jiffies(5)
  85
  86 /**
  87  * struct ep93xx_ac97_info - EP93xx AC97 controller info structure
  88  * @lock: mutex serializing access to the bus (slot 1 & 2 ops)
  89  * @dev: pointer to the platform device dev structure
  90  * @regs: mapped AC97 controller registers
  91  * @done: bus ops wait here for an interrupt
  92  */
  93 struct ep93xx_ac97_info {
  94         struct mutex            lock;
  95         struct device           *dev;
  96         void __iomem            *regs;
  97         struct completion       done;
  98 };
  99
 100 /* currently ALSA only supports a single AC97 device */
 101 static struct ep93xx_ac97_info *ep93xx_ac97_info;
 102
 103 static struct ep93xx_pcm_dma_params ep93xx_ac97_pcm_out = {
 104         .name           = "ac97-pcm-out",
 105         .dma_port       = EP93XX_DMA_AAC1,
 106 };
 107
 108 static struct ep93xx_pcm_dma_params ep93xx_ac97_pcm_in = {
 109         .name           = "ac97-pcm-in",
 110         .dma_port       = EP93XX_DMA_AAC1,
 111 };
 112
 113 static inline unsigned ep93xx_ac97_read_reg(struct ep93xx_ac97_info *info,
 114                                             unsigned reg)
 115 {
 116         return __raw_readl(info->regs + reg);
 117 }
 118
 119 static inline void ep93xx_ac97_write_reg(struct ep93xx_ac97_info *info,
 120                                          unsigned reg, unsigned val)
 121 {
 122         __raw_writel(val, info->regs + reg);
 123 }
 124
 125 static unsigned short ep93xx_ac97_read(struct snd_ac97 *ac97,
 126                                        unsigned short reg)
 127 {
 128         struct ep93xx_ac97_info *info = ep93xx_ac97_info;
 129         unsigned short val;
 130
 131         mutex_lock(&info->lock);
 132
 133         ep93xx_ac97_write_reg(info, AC97S1DATA, reg);
 134         ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2RXVALID);
 135         if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT)) {
 136                 dev_warn(info->dev, "timeout reading register %x\n", reg);
 137                 mutex_unlock(&info->lock);
 138                 return -ETIMEDOUT;
 139         }
 140         val = (unsigned short)ep93xx_ac97_read_reg(info, AC97S2DATA);
 141
 142         mutex_unlock(&info->lock);
 143         return val;
 144 }
 145
 146 static void ep93xx_ac97_write(struct snd_ac97 *ac97,
 147                               unsigned short reg,
 148                               unsigned short val)
 149 {
 150         struct ep93xx_ac97_info *info = ep93xx_ac97_info;
 151
 152         mutex_lock(&info->lock);
 153
 154         /*
 155          * Writes to the codec need to be done so that slot 2 is filled in
 156          * before slot 1.
 157          */
 158         ep93xx_ac97_write_reg(info, AC97S2DATA, val);
 159         ep93xx_ac97_write_reg(info, AC97S1DATA, reg);
 160
 161         ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2TXCOMPLETE);
 162         if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
 163                 dev_warn(info->dev, "timeout writing register %x\n", reg);
 164
 165         mutex_unlock(&info->lock);
 166 }
 167
 168 static void ep93xx_ac97_warm_reset(struct snd_ac97 *ac97)
 169 {
 170         struct ep93xx_ac97_info *info = ep93xx_ac97_info;
 171
 172         mutex_lock(&info->lock);
 173
 174         /*
 175          * We are assuming that before this functions gets called, the codec
 176          * BIT_CLK is stopped by forcing the codec into powerdown mode. We can
 177          * control the SYNC signal directly via AC97SYNC register. Using
 178          * TIMEDSYNC the controller will keep the SYNC high > 1us.
 179          */
 180         ep93xx_ac97_write_reg(info, AC97SYNC, AC97SYNC_TIMEDSYNC);
 181         ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY);
 182         if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
 183                 dev_warn(info->dev, "codec warm reset timeout\n");
 184
 185         mutex_unlock(&info->lock);
 186 }
 187
 188 static void ep93xx_ac97_cold_reset(struct snd_ac97 *ac97)
 189 {
 190         struct ep93xx_ac97_info *info = ep93xx_ac97_info;
 191
 192         mutex_lock(&info->lock);
 193
 194         /*
 195          * For doing cold reset, we disable the AC97 controller interface, clear
 196          * WINT and CODECREADY bits, and finally enable the interface again.
 197          */
 198         ep93xx_ac97_write_reg(info, AC97GCR, 0);
 199         ep93xx_ac97_write_reg(info, AC97EOI, AC97EOI_CODECREADY | AC97EOI_WINT);
 200         ep93xx_ac97_write_reg(info, AC97GCR, AC97GCR_AC97IFE);
 201
 202         /*
 203          * Now, assert the reset and wait for the codec to become ready.
 204          */
 205         ep93xx_ac97_write_reg(info, AC97RESET, AC97RESET_TIMEDRESET);
 206         ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY);
 207         if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
 208                 dev_warn(info->dev, "codec cold reset timeout\n");
 209
 210         /*
 211          * Give the codec some time to come fully out from the reset. This way
 212          * we ensure that the subsequent reads/writes will work.
 213          */
 214         usleep_range(15000, 20000);
 215
 216         mutex_unlock(&info->lock);
 217 }
 218
 219 static irqreturn_t ep93xx_ac97_interrupt(int irq, void *dev_id)
 220 {
 221         struct ep93xx_ac97_info *info = dev_id;
 222         unsigned status, mask;
 223
 224         /*
 225          * Just mask out the interrupt and wake up the waiting thread.
 226          * Interrupts are cleared via reading/writing to slot 1 & 2 registers by
 227          * the waiting thread.
 228          */
 229         status = ep93xx_ac97_read_reg(info, AC97GIS);
 230         mask = ep93xx_ac97_read_reg(info, AC97IM);
 231         mask &= ~status;
 232         ep93xx_ac97_write_reg(info, AC97IM, mask);
 233
 234         complete(&info->done);
 235         return IRQ_HANDLED;
 236 }
 237
 238 struct snd_ac97_bus_ops soc_ac97_ops = {
 239         .read           = ep93xx_ac97_read,
 240         .write          = ep93xx_ac97_write,
 241         .reset          = ep93xx_ac97_cold_reset,
 242         .warm_reset     = ep93xx_ac97_warm_reset,
 243 };
 244 EXPORT_SYMBOL_GPL(soc_ac97_ops);
 245
 246 static int ep93xx_ac97_trigger(struct snd_pcm_substream *substream,
 247                                int cmd, struct snd_soc_dai *dai)
 248 {
 249         struct ep93xx_ac97_info *info = snd_soc_dai_get_drvdata(dai);
 250         unsigned v = 0;
 251
 252         switch (cmd) {
 253         case SNDRV_PCM_TRIGGER_START:
 254         case SNDRV_PCM_TRIGGER_RESUME:
 255         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 256                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 257                         /*
 258                          * Enable compact mode, TX slots 3 & 4, and the TX FIFO
 259                          * itself.
 260                          */
 261                         v |= AC97TXCR_CM;
 262                         v |= AC97TXCR_TX3 | AC97TXCR_TX4;
 263                         v |= AC97TXCR_TEN;
 264                         ep93xx_ac97_write_reg(info, AC97TXCR(1), v);
 265                 } else {
 266                         /*
 267                          * Enable compact mode, RX slots 3 & 4, and the RX FIFO
 268                          * itself.
 269                          */
 270                         v |= AC97RXCR_CM;
 271                         v |= AC97RXCR_RX3 | AC97RXCR_RX4;
 272                         v |= AC97RXCR_REN;
 273                         ep93xx_ac97_write_reg(info, AC97RXCR(1), v);
 274                 }
 275                 break;
 276
 277         case SNDRV_PCM_TRIGGER_STOP:
 278         case SNDRV_PCM_TRIGGER_SUSPEND:
 279         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 280                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 281                         /*
 282                          * As per Cirrus EP93xx errata described below:
 283                          *
 284                          * http://www.cirrus.com/en/pubs/errata/ER667E2B.pdf
 285                          *
 286                          * we will wait for the TX FIFO to be empty before
 287                          * clearing the TEN bit.
 288                          */
 289                         unsigned long timeout = jiffies + AC97_TIMEOUT;
 290
 291                         do {
 292                                 v = ep93xx_ac97_read_reg(info, AC97SR(1));
 293                                 if (time_after(jiffies, timeout)) {
 294                                         dev_warn(info->dev, "TX timeout\n");
 295                                         break;
 296                                 }
 297                         } while (!(v & (AC97SR_TXFE | AC97SR_TXUE)));
 298
 299                         /* disable the TX FIFO */
 300                         ep93xx_ac97_write_reg(info, AC97TXCR(1), 0);
 301                 } else {
 302                         /* disable the RX FIFO */
 303                         ep93xx_ac97_write_reg(info, AC97RXCR(1), 0);
 304                 }
 305                 break;
 306
 307         default:
 308                 dev_warn(info->dev, "unknown command %d\n", cmd);
 309                 return -EINVAL;
 310         }
 311
 312         return 0;
 313 }
 314
 315 static int ep93xx_ac97_startup(struct snd_pcm_substream *substream,
 316                                struct snd_soc_dai *dai)
 317 {
 318         struct ep93xx_pcm_dma_params *dma_data;
 319
 320         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 321                 dma_data = &ep93xx_ac97_pcm_out;
 322         else
 323                 dma_data = &ep93xx_ac97_pcm_in;
 324
 325         snd_soc_dai_set_dma_data(dai, substream, dma_data);
 326         return 0;
 327 }
 328
 329 static const struct snd_soc_dai_ops ep93xx_ac97_dai_ops = {
 330         .startup        = ep93xx_ac97_startup,
 331         .trigger        = ep93xx_ac97_trigger,
 332 };
 333
 334 static struct snd_soc_dai_driver ep93xx_ac97_dai = {
 335         .name           = "ep93xx-ac97",
 336         .id             = 0,
 337         .ac97_control   = 1,
 338         .playback       = {
 339                 .stream_name    = "AC97 Playback",
 340                 .channels_min   = 2,
 341                 .channels_max   = 2,
 342                 .rates          = SNDRV_PCM_RATE_8000_48000,
 343                 .formats        = SNDRV_PCM_FMTBIT_S16_LE,
 344         },
 345         .capture        = {
 346                 .stream_name    = "AC97 Capture",
 347                 .channels_min   = 2,
 348                 .channels_max   = 2,
 349                 .rates          = SNDRV_PCM_RATE_8000_48000,
 350                 .formats        = SNDRV_PCM_FMTBIT_S16_LE,
 351         },
 352         .ops                    = &ep93xx_ac97_dai_ops,
 353 };
 354
 355 static int __devinit ep93xx_ac97_probe(struct platform_device *pdev)
 356 {
 357         struct ep93xx_ac97_info *info;
 358         struct resource *res;
 359         unsigned int irq;
 360         int ret;
 361
 362         info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
 363         if (!info)
 364                 return -ENOMEM;
 365
 366         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 367         if (!res)
 368                 return -ENODEV;
 369
 370         info->regs = devm_request_and_ioremap(&pdev->dev, res);
 371         if (!info->regs)
 372                 return -ENXIO;
 373
 374         irq = platform_get_irq(pdev, 0);
 375         if (!irq)
 376                 return -ENODEV;
 377
 378         ret = devm_request_irq(&pdev->dev, irq, ep93xx_ac97_interrupt,
 379                                IRQF_TRIGGER_HIGH, pdev->name, info);
 380         if (ret)
 381                 goto fail;
 382
 383         dev_set_drvdata(&pdev->dev, info);
 384
 385         mutex_init(&info->lock);
 386         init_completion(&info->done);
 387         info->dev = &pdev->dev;
 388
 389         ep93xx_ac97_info = info;
 390         platform_set_drvdata(pdev, info);
 391
 392         ret = snd_soc_register_dai(&pdev->dev, &ep93xx_ac97_dai);
 393         if (ret)
 394                 goto fail;
 395
 396         return 0;
 397
 398 fail:
 399         platform_set_drvdata(pdev, NULL);
 400         ep93xx_ac97_info = NULL;
 401         dev_set_drvdata(&pdev->dev, NULL);
 402         return ret;
 403 }
 404
 405 static int __devexit ep93xx_ac97_remove(struct platform_device *pdev)
 406 {
 407         struct ep93xx_ac97_info *info = platform_get_drvdata(pdev);
 408
 409         snd_soc_unregister_dai(&pdev->dev);
 410
 411         /* disable the AC97 controller */
 412         ep93xx_ac97_write_reg(info, AC97GCR, 0);
 413
 414         platform_set_drvdata(pdev, NULL);
 415         ep93xx_ac97_info = NULL;
 416         dev_set_drvdata(&pdev->dev, NULL);
 417
 418         return 0;
 419 }
 420
 421 static struct platform_driver ep93xx_ac97_driver = {
 422         .probe  = ep93xx_ac97_probe,
 423         .remove = __devexit_p(ep93xx_ac97_remove),
 424         .driver = {
 425                 .name = "ep93xx-ac97",
 426                 .owner = THIS_MODULE,
 427         },
 428 };
 429
 430 module_platform_driver(ep93xx_ac97_driver);
 431
 432 MODULE_DESCRIPTION("EP93xx AC97 ASoC Driver");
 433 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>");
 434 MODULE_LICENSE("GPL");
 435 MODULE_ALIAS("platform:ep93xx-ac97");