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  * @mem: physical memory resource for the registers
  91  * @regs: mapped AC97 controller registers
  92  * @irq: AC97 interrupt number
  93  * @done: bus ops wait here for an interrupt
  94  */
  95 struct ep93xx_ac97_info {
  96         struct mutex            lock;
  97         struct device           *dev;
  98         struct resource         *mem;
  99         void __iomem            *regs;
 100         int                     irq;
 101         struct completion       done;
 102 };
 103
 104 /* currently ALSA only supports a single AC97 device */
 105 static struct ep93xx_ac97_info *ep93xx_ac97_info;
 106
 107 static struct ep93xx_pcm_dma_params ep93xx_ac97_pcm_out = {
 108         .name           = "ac97-pcm-out",
 109         .dma_port       = EP93XX_DMA_AAC1,
 110 };
 111
 112 static struct ep93xx_pcm_dma_params ep93xx_ac97_pcm_in = {
 113         .name           = "ac97-pcm-in",
 114         .dma_port       = EP93XX_DMA_AAC1,
 115 };
 116
 117 static inline unsigned ep93xx_ac97_read_reg(struct ep93xx_ac97_info *info,
 118                                             unsigned reg)
 119 {
 120         return __raw_readl(info->regs + reg);
 121 }
 122
 123 static inline void ep93xx_ac97_write_reg(struct ep93xx_ac97_info *info,
 124                                          unsigned reg, unsigned val)
 125 {
 126         __raw_writel(val, info->regs + reg);
 127 }
 128
 129 static unsigned short ep93xx_ac97_read(struct snd_ac97 *ac97,
 130                                        unsigned short reg)
 131 {
 132         struct ep93xx_ac97_info *info = ep93xx_ac97_info;
 133         unsigned short val;
 134
 135         mutex_lock(&info->lock);
 136
 137         ep93xx_ac97_write_reg(info, AC97S1DATA, reg);
 138         ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2RXVALID);
 139         if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT)) {
 140                 dev_warn(info->dev, "timeout reading register %x\n", reg);
 141                 mutex_unlock(&info->lock);
 142                 return -ETIMEDOUT;
 143         }
 144         val = (unsigned short)ep93xx_ac97_read_reg(info, AC97S2DATA);
 145
 146         mutex_unlock(&info->lock);
 147         return val;
 148 }
 149
 150 static void ep93xx_ac97_write(struct snd_ac97 *ac97,
 151                               unsigned short reg,
 152                               unsigned short val)
 153 {
 154         struct ep93xx_ac97_info *info = ep93xx_ac97_info;
 155
 156         mutex_lock(&info->lock);
 157
 158         /*
 159          * Writes to the codec need to be done so that slot 2 is filled in
 160          * before slot 1.
 161          */
 162         ep93xx_ac97_write_reg(info, AC97S2DATA, val);
 163         ep93xx_ac97_write_reg(info, AC97S1DATA, reg);
 164
 165         ep93xx_ac97_write_reg(info, AC97IM, AC97_SLOT2TXCOMPLETE);
 166         if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
 167                 dev_warn(info->dev, "timeout writing register %x\n", reg);
 168
 169         mutex_unlock(&info->lock);
 170 }
 171
 172 static void ep93xx_ac97_warm_reset(struct snd_ac97 *ac97)
 173 {
 174         struct ep93xx_ac97_info *info = ep93xx_ac97_info;
 175
 176         mutex_lock(&info->lock);
 177
 178         /*
 179          * We are assuming that before this functions gets called, the codec
 180          * BIT_CLK is stopped by forcing the codec into powerdown mode. We can
 181          * control the SYNC signal directly via AC97SYNC register. Using
 182          * TIMEDSYNC the controller will keep the SYNC high > 1us.
 183          */
 184         ep93xx_ac97_write_reg(info, AC97SYNC, AC97SYNC_TIMEDSYNC);
 185         ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY);
 186         if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
 187                 dev_warn(info->dev, "codec warm reset timeout\n");
 188
 189         mutex_unlock(&info->lock);
 190 }
 191
 192 static void ep93xx_ac97_cold_reset(struct snd_ac97 *ac97)
 193 {
 194         struct ep93xx_ac97_info *info = ep93xx_ac97_info;
 195
 196         mutex_lock(&info->lock);
 197
 198         /*
 199          * For doing cold reset, we disable the AC97 controller interface, clear
 200          * WINT and CODECREADY bits, and finally enable the interface again.
 201          */
 202         ep93xx_ac97_write_reg(info, AC97GCR, 0);
 203         ep93xx_ac97_write_reg(info, AC97EOI, AC97EOI_CODECREADY | AC97EOI_WINT);
 204         ep93xx_ac97_write_reg(info, AC97GCR, AC97GCR_AC97IFE);
 205
 206         /*
 207          * Now, assert the reset and wait for the codec to become ready.
 208          */
 209         ep93xx_ac97_write_reg(info, AC97RESET, AC97RESET_TIMEDRESET);
 210         ep93xx_ac97_write_reg(info, AC97IM, AC97_CODECREADY);
 211         if (!wait_for_completion_timeout(&info->done, AC97_TIMEOUT))
 212                 dev_warn(info->dev, "codec cold reset timeout\n");
 213
 214         /*
 215          * Give the codec some time to come fully out from the reset. This way
 216          * we ensure that the subsequent reads/writes will work.
 217          */
 218         usleep_range(15000, 20000);
 219
 220         mutex_unlock(&info->lock);
 221 }
 222
 223 static irqreturn_t ep93xx_ac97_interrupt(int irq, void *dev_id)
 224 {
 225         struct ep93xx_ac97_info *info = dev_id;
 226         unsigned status, mask;
 227
 228         /*
 229          * Just mask out the interrupt and wake up the waiting thread.
 230          * Interrupts are cleared via reading/writing to slot 1 & 2 registers by
 231          * the waiting thread.
 232          */
 233         status = ep93xx_ac97_read_reg(info, AC97GIS);
 234         mask = ep93xx_ac97_read_reg(info, AC97IM);
 235         mask &= ~status;
 236         ep93xx_ac97_write_reg(info, AC97IM, mask);
 237
 238         complete(&info->done);
 239         return IRQ_HANDLED;
 240 }
 241
 242 struct snd_ac97_bus_ops soc_ac97_ops = {
 243         .read           = ep93xx_ac97_read,
 244         .write          = ep93xx_ac97_write,
 245         .reset          = ep93xx_ac97_cold_reset,
 246         .warm_reset     = ep93xx_ac97_warm_reset,
 247 };
 248 EXPORT_SYMBOL_GPL(soc_ac97_ops);
 249
 250 static int ep93xx_ac97_trigger(struct snd_pcm_substream *substream,
 251                                int cmd, struct snd_soc_dai *dai)
 252 {
 253         struct ep93xx_ac97_info *info = snd_soc_dai_get_drvdata(dai);
 254         unsigned v = 0;
 255
 256         switch (cmd) {
 257         case SNDRV_PCM_TRIGGER_START:
 258         case SNDRV_PCM_TRIGGER_RESUME:
 259         case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
 260                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 261                         /*
 262                          * Enable compact mode, TX slots 3 & 4, and the TX FIFO
 263                          * itself.
 264                          */
 265                         v |= AC97TXCR_CM;
 266                         v |= AC97TXCR_TX3 | AC97TXCR_TX4;
 267                         v |= AC97TXCR_TEN;
 268                         ep93xx_ac97_write_reg(info, AC97TXCR(1), v);
 269                 } else {
 270                         /*
 271                          * Enable compact mode, RX slots 3 & 4, and the RX FIFO
 272                          * itself.
 273                          */
 274                         v |= AC97RXCR_CM;
 275                         v |= AC97RXCR_RX3 | AC97RXCR_RX4;
 276                         v |= AC97RXCR_REN;
 277                         ep93xx_ac97_write_reg(info, AC97RXCR(1), v);
 278                 }
 279                 break;
 280
 281         case SNDRV_PCM_TRIGGER_STOP:
 282         case SNDRV_PCM_TRIGGER_SUSPEND:
 283         case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
 284                 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
 285                         /*
 286                          * As per Cirrus EP93xx errata described below:
 287                          *
 288                          * http://www.cirrus.com/en/pubs/errata/ER667E2B.pdf
 289                          *
 290                          * we will wait for the TX FIFO to be empty before
 291                          * clearing the TEN bit.
 292                          */
 293                         unsigned long timeout = jiffies + AC97_TIMEOUT;
 294
 295                         do {
 296                                 v = ep93xx_ac97_read_reg(info, AC97SR(1));
 297                                 if (time_after(jiffies, timeout)) {
 298                                         dev_warn(info->dev, "TX timeout\n");
 299                                         break;
 300                                 }
 301                         } while (!(v & (AC97SR_TXFE | AC97SR_TXUE)));
 302
 303                         /* disable the TX FIFO */
 304                         ep93xx_ac97_write_reg(info, AC97TXCR(1), 0);
 305                 } else {
 306                         /* disable the RX FIFO */
 307                         ep93xx_ac97_write_reg(info, AC97RXCR(1), 0);
 308                 }
 309                 break;
 310
 311         default:
 312                 dev_warn(info->dev, "unknown command %d\n", cmd);
 313                 return -EINVAL;
 314         }
 315
 316         return 0;
 317 }
 318
 319 static int ep93xx_ac97_startup(struct snd_pcm_substream *substream,
 320                                struct snd_soc_dai *dai)
 321 {
 322         struct ep93xx_pcm_dma_params *dma_data;
 323
 324         if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
 325                 dma_data = &ep93xx_ac97_pcm_out;
 326         else
 327                 dma_data = &ep93xx_ac97_pcm_in;
 328
 329         snd_soc_dai_set_dma_data(dai, substream, dma_data);
 330         return 0;
 331 }
 332
 333 static const struct snd_soc_dai_ops ep93xx_ac97_dai_ops = {
 334         .startup        = ep93xx_ac97_startup,
 335         .trigger        = ep93xx_ac97_trigger,
 336 };
 337
 338 static struct snd_soc_dai_driver ep93xx_ac97_dai = {
 339         .name           = "ep93xx-ac97",
 340         .id             = 0,
 341         .ac97_control   = 1,
 342         .playback       = {
 343                 .stream_name    = "AC97 Playback",
 344                 .channels_min   = 2,
 345                 .channels_max   = 2,
 346                 .rates          = SNDRV_PCM_RATE_8000_48000,
 347                 .formats        = SNDRV_PCM_FMTBIT_S16_LE,
 348         },
 349         .capture        = {
 350                 .stream_name    = "AC97 Capture",
 351                 .channels_min   = 2,
 352                 .channels_max   = 2,
 353                 .rates          = SNDRV_PCM_RATE_8000_48000,
 354                 .formats        = SNDRV_PCM_FMTBIT_S16_LE,
 355         },
 356         .ops                    = &ep93xx_ac97_dai_ops,
 357 };
 358
 359 static int __devinit ep93xx_ac97_probe(struct platform_device *pdev)
 360 {
 361         struct ep93xx_ac97_info *info;
 362         int ret;
 363
 364         info = kzalloc(sizeof(struct ep93xx_ac97_info), GFP_KERNEL);
 365         if (!info)
 366                 return -ENOMEM;
 367
 368         dev_set_drvdata(&pdev->dev, info);
 369
 370         mutex_init(&info->lock);
 371         init_completion(&info->done);
 372         info->dev = &pdev->dev;
 373
 374         info->mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 375         if (!info->mem) {
 376                 ret = -ENXIO;
 377                 goto fail_free_info;
 378         }
 379
 380         info->irq = platform_get_irq(pdev, 0);
 381         if (!info->irq) {
 382                 ret = -ENXIO;
 383                 goto fail_free_info;
 384         }
 385
 386         if (!request_mem_region(info->mem->start, resource_size(info->mem),
 387                                 pdev->name)) {
 388                 ret = -EBUSY;
 389                 goto fail_free_info;
 390         }
 391
 392         info->regs = ioremap(info->mem->start, resource_size(info->mem));
 393         if (!info->regs) {
 394                 ret = -ENOMEM;
 395                 goto fail_release_mem;
 396         }
 397
 398         ret = request_irq(info->irq, ep93xx_ac97_interrupt, IRQF_TRIGGER_HIGH,
 399                           pdev->name, info);
 400         if (ret)
 401                 goto fail_unmap_mem;
 402
 403         ep93xx_ac97_info = info;
 404         platform_set_drvdata(pdev, info);
 405
 406         ret = snd_soc_register_dai(&pdev->dev, &ep93xx_ac97_dai);
 407         if (ret)
 408                 goto fail_free_irq;
 409
 410         return 0;
 411
 412 fail_free_irq:
 413         platform_set_drvdata(pdev, NULL);
 414         free_irq(info->irq, info);
 415 fail_unmap_mem:
 416         iounmap(info->regs);
 417 fail_release_mem:
 418         release_mem_region(info->mem->start, resource_size(info->mem));
 419 fail_free_info:
 420         kfree(info);
 421
 422         return ret;
 423 }
 424
 425 static int __devexit ep93xx_ac97_remove(struct platform_device *pdev)
 426 {
 427         struct ep93xx_ac97_info *info = platform_get_drvdata(pdev);
 428
 429         snd_soc_unregister_dai(&pdev->dev);
 430
 431         /* disable the AC97 controller */
 432         ep93xx_ac97_write_reg(info, AC97GCR, 0);
 433
 434         free_irq(info->irq, info);
 435         iounmap(info->regs);
 436         release_mem_region(info->mem->start, resource_size(info->mem));
 437         platform_set_drvdata(pdev, NULL);
 438         kfree(info);
 439
 440         return 0;
 441 }
 442
 443 static struct platform_driver ep93xx_ac97_driver = {
 444         .probe  = ep93xx_ac97_probe,
 445         .remove = __devexit_p(ep93xx_ac97_remove),
 446         .driver = {
 447                 .name = "ep93xx-ac97",
 448                 .owner = THIS_MODULE,
 449         },
 450 };
 451
 452 module_platform_driver(ep93xx_ac97_driver);
 453
 454 MODULE_DESCRIPTION("EP93xx AC97 ASoC Driver");
 455 MODULE_AUTHOR("Mika Westerberg <mika.westerberg@iki.fi>");
 456 MODULE_LICENSE("GPL");
 457 MODULE_ALIAS("platform:ep93xx-ac97");