drivers/gpu/drm/bridge/dw_hdmi-ahb-audio.c

   1 /*
   2  * DesignWare HDMI audio driver
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * Written and tested against the Designware HDMI Tx found in iMX6.
   9  */
  10 #include <linux/io.h>
  11 #include <linux/interrupt.h>
  12 #include <linux/module.h>
  13 #include <linux/platform_device.h>
  14 #include <drm/bridge/dw_hdmi.h>
  15 #include <drm/drm_edid.h>
  16
  17 #include <sound/asoundef.h>
  18 #include <sound/core.h>
  19 #include <sound/initval.h>
  20 #include <sound/pcm.h>
  21 #include <sound/pcm_drm_eld.h>
  22 #include <sound/pcm_iec958.h>
  23
  24 #include "dw_hdmi-audio.h"
  25
  26 #define DRIVER_NAME "dw-hdmi-ahb-audio"
  27
  28 /* Provide some bits rather than bit offsets */
  29 enum {
  30         HDMI_AHB_DMA_CONF0_SW_FIFO_RST = BIT(7),
  31         HDMI_AHB_DMA_CONF0_EN_HLOCK = BIT(3),
  32         HDMI_AHB_DMA_START_START = BIT(0),
  33         HDMI_AHB_DMA_STOP_STOP = BIT(0),
  34         HDMI_IH_MUTE_AHBDMAAUD_STAT0_ERROR = BIT(5),
  35         HDMI_IH_MUTE_AHBDMAAUD_STAT0_LOST = BIT(4),
  36         HDMI_IH_MUTE_AHBDMAAUD_STAT0_RETRY = BIT(3),
  37         HDMI_IH_MUTE_AHBDMAAUD_STAT0_DONE = BIT(2),
  38         HDMI_IH_MUTE_AHBDMAAUD_STAT0_BUFFFULL = BIT(1),
  39         HDMI_IH_MUTE_AHBDMAAUD_STAT0_BUFFEMPTY = BIT(0),
  40         HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL =
  41                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_ERROR |
  42                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_LOST |
  43                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_RETRY |
  44                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_DONE |
  45                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_BUFFFULL |
  46                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_BUFFEMPTY,
  47         HDMI_IH_AHBDMAAUD_STAT0_ERROR = BIT(5),
  48         HDMI_IH_AHBDMAAUD_STAT0_LOST = BIT(4),
  49         HDMI_IH_AHBDMAAUD_STAT0_RETRY = BIT(3),
  50         HDMI_IH_AHBDMAAUD_STAT0_DONE = BIT(2),
  51         HDMI_IH_AHBDMAAUD_STAT0_BUFFFULL = BIT(1),
  52         HDMI_IH_AHBDMAAUD_STAT0_BUFFEMPTY = BIT(0),
  53         HDMI_IH_AHBDMAAUD_STAT0_ALL =
  54                 HDMI_IH_AHBDMAAUD_STAT0_ERROR |
  55                 HDMI_IH_AHBDMAAUD_STAT0_LOST |
  56                 HDMI_IH_AHBDMAAUD_STAT0_RETRY |
  57                 HDMI_IH_AHBDMAAUD_STAT0_DONE |
  58                 HDMI_IH_AHBDMAAUD_STAT0_BUFFFULL |
  59                 HDMI_IH_AHBDMAAUD_STAT0_BUFFEMPTY,
  60         HDMI_AHB_DMA_CONF0_INCR16 = 2 << 1,
  61         HDMI_AHB_DMA_CONF0_INCR8 = 1 << 1,
  62         HDMI_AHB_DMA_CONF0_INCR4 = 0,
  63         HDMI_AHB_DMA_CONF0_BURST_MODE = BIT(0),
  64         HDMI_AHB_DMA_MASK_DONE = BIT(7),
  65
  66         HDMI_REVISION_ID = 0x0001,
  67         HDMI_IH_AHBDMAAUD_STAT0 = 0x0109,
  68         HDMI_IH_MUTE_AHBDMAAUD_STAT0 = 0x0189,
  69         HDMI_FC_AUDICONF2 = 0x1027,
  70         HDMI_FC_AUDSCONF = 0x1063,
  71         HDMI_FC_AUDSCONF_LAYOUT1 = 1 << 0,
  72         HDMI_FC_AUDSCONF_LAYOUT0 = 0 << 0,
  73         HDMI_AHB_DMA_CONF0 = 0x3600,
  74         HDMI_AHB_DMA_START = 0x3601,
  75         HDMI_AHB_DMA_STOP = 0x3602,
  76         HDMI_AHB_DMA_THRSLD = 0x3603,
  77         HDMI_AHB_DMA_STRADDR0 = 0x3604,
  78         HDMI_AHB_DMA_STPADDR0 = 0x3608,
  79         HDMI_AHB_DMA_MASK = 0x3614,
  80         HDMI_AHB_DMA_POL = 0x3615,
  81         HDMI_AHB_DMA_CONF1 = 0x3616,
  82         HDMI_AHB_DMA_BUFFPOL = 0x361a,
  83 };
  84
  85 struct dw_hdmi_channel_conf {
  86         u8 conf1;
  87         u8 ca;
  88 };
  89
  90 /*
  91  * The default mapping of ALSA channels to HDMI channels and speaker
  92  * allocation bits.  Note that we can't do channel remapping here -
  93  * channels must be in the same order.
  94  *
  95  * Mappings for alsa-lib pcm/surround*.conf files:
  96  *
  97  *              Front   Sur4.0  Sur4.1  Sur5.0  Sur5.1  Sur7.1
  98  * Channels     2       4       6       6       6       8
  99  *
 100  * Our mapping from ALSA channel to CEA686D speaker name and HDMI channel:
 101  *
 102  *                              Number of ALSA channels
 103  * ALSA Channel 2       3       4       5       6       7       8
 104  * 0            FL:0    =       =       =       =       =       =
 105  * 1            FR:1    =       =       =       =       =       =
 106  * 2                    FC:3    RL:4    LFE:2   =       =       =
 107  * 3                            RR:5    RL:4    FC:3    =       =
 108  * 4                                    RR:5    RL:4    =       =
 109  * 5                                            RR:5    =       =
 110  * 6                                                    RC:6    =
 111  * 7                                                    RLC/FRC RLC/FRC
 112  */
 113 static struct dw_hdmi_channel_conf default_hdmi_channel_config[7] = {
 114         { 0x03, 0x00 }, /* FL,FR */
 115         { 0x0b, 0x02 }, /* FL,FR,FC */
 116         { 0x33, 0x08 }, /* FL,FR,RL,RR */
 117         { 0x37, 0x09 }, /* FL,FR,LFE,RL,RR */
 118         { 0x3f, 0x0b }, /* FL,FR,LFE,FC,RL,RR */
 119         { 0x7f, 0x0f }, /* FL,FR,LFE,FC,RL,RR,RC */
 120         { 0xff, 0x13 }, /* FL,FR,LFE,FC,RL,RR,[FR]RC,[FR]LC */
 121 };
 122
 123 struct snd_dw_hdmi {
 124         struct snd_card *card;
 125         struct snd_pcm *pcm;
 126         spinlock_t lock;
 127         struct dw_hdmi_audio_data data;
 128         struct snd_pcm_substream *substream;
 129         void (*reformat)(struct snd_dw_hdmi *, size_t, size_t);
 130         void *buf_src;
 131         void *buf_dst;
 132         dma_addr_t buf_addr;
 133         unsigned buf_offset;
 134         unsigned buf_period;
 135         unsigned buf_size;
 136         unsigned channels;
 137         u8 revision;
 138         u8 iec_offset;
 139         u8 cs[192][8];
 140 };
 141
 142 static void dw_hdmi_writel(u32 val, void __iomem *ptr)
 143 {
 144         writeb_relaxed(val, ptr);
 145         writeb_relaxed(val >> 8, ptr + 1);
 146         writeb_relaxed(val >> 16, ptr + 2);
 147         writeb_relaxed(val >> 24, ptr + 3);
 148 }
 149
 150 /*
 151  * Convert to hardware format: The userspace buffer contains IEC958 samples,
 152  * with the PCUV bits in bits 31..28 and audio samples in bits 27..4.  We
 153  * need these to be in bits 27..24, with the IEC B bit in bit 28, and audio
 154  * samples in 23..0.
 155  *
 156  * Default preamble in bits 3..0: 8 = block start, 4 = even 2 = odd
 157  *
 158  * Ideally, we could do with having the data properly formatted in userspace.
 159  */
 160 static void dw_hdmi_reformat_iec958(struct snd_dw_hdmi *dw,
 161         size_t offset, size_t bytes)
 162 {
 163         u32 *src = dw->buf_src + offset;
 164         u32 *dst = dw->buf_dst + offset;
 165         u32 *end = dw->buf_src + offset + bytes;
 166
 167         do {
 168                 u32 b, sample = *src++;
 169
 170                 b = (sample & 8) << (28 - 3);
 171
 172                 sample >>= 4;
 173
 174                 *dst++ = sample | b;
 175         } while (src < end);
 176 }
 177
 178 static u32 parity(u32 sample)
 179 {
 180         sample ^= sample >> 16;
 181         sample ^= sample >> 8;
 182         sample ^= sample >> 4;
 183         sample ^= sample >> 2;
 184         sample ^= sample >> 1;
 185         return (sample & 1) << 27;
 186 }
 187
 188 static void dw_hdmi_reformat_s24(struct snd_dw_hdmi *dw,
 189         size_t offset, size_t bytes)
 190 {
 191         u32 *src = dw->buf_src + offset;
 192         u32 *dst = dw->buf_dst + offset;
 193         u32 *end = dw->buf_src + offset + bytes;
 194
 195         do {
 196                 unsigned i;
 197                 u8 *cs;
 198
 199                 cs = dw->cs[dw->iec_offset++];
 200                 if (dw->iec_offset >= 192)
 201                         dw->iec_offset = 0;
 202
 203                 i = dw->channels;
 204                 do {
 205                         u32 sample = *src++;
 206
 207                         sample &= ~0xff000000;
 208                         sample |= *cs++ << 24;
 209                         sample |= parity(sample & ~0xf8000000);
 210
 211                         *dst++ = sample;
 212                 } while (--i);
 213         } while (src < end);
 214 }
 215
 216 static void dw_hdmi_create_cs(struct snd_dw_hdmi *dw,
 217         struct snd_pcm_runtime *runtime)
 218 {
 219         u8 cs[4];
 220         unsigned ch, i, j;
 221
 222         snd_pcm_create_iec958_consumer(runtime, cs, sizeof(cs));
 223
 224         memset(dw->cs, 0, sizeof(dw->cs));
 225
 226         for (ch = 0; ch < 8; ch++) {
 227                 cs[2] &= ~IEC958_AES2_CON_CHANNEL;
 228                 cs[2] |= (ch + 1) << 4;
 229
 230                 for (i = 0; i < ARRAY_SIZE(cs); i++) {
 231                         unsigned c = cs[i];
 232
 233                         for (j = 0; j < 8; j++, c >>= 1)
 234                                 dw->cs[i * 8 + j][ch] = (c & 1) << 2;
 235                 }
 236         }
 237         dw->cs[0][0] |= BIT(4);
 238 }
 239
 240 static void dw_hdmi_start_dma(struct snd_dw_hdmi *dw)
 241 {
 242         void __iomem *base = dw->data.base;
 243         unsigned offset = dw->buf_offset;
 244         unsigned period = dw->buf_period;
 245         u32 start, stop;
 246
 247         dw->reformat(dw, offset, period);
 248
 249         /* Clear all irqs before enabling irqs and starting DMA */
 250         writeb_relaxed(HDMI_IH_AHBDMAAUD_STAT0_ALL,
 251                        base + HDMI_IH_AHBDMAAUD_STAT0);
 252
 253         start = dw->buf_addr + offset;
 254         stop = start + period - 1;
 255
 256         /* Setup the hardware start/stop addresses */
 257         dw_hdmi_writel(start, base + HDMI_AHB_DMA_STRADDR0);
 258         dw_hdmi_writel(stop, base + HDMI_AHB_DMA_STPADDR0);
 259
 260         writeb_relaxed((u8)~HDMI_AHB_DMA_MASK_DONE, base + HDMI_AHB_DMA_MASK);
 261         writeb(HDMI_AHB_DMA_START_START, base + HDMI_AHB_DMA_START);
 262
 263         offset += period;
 264         if (offset >= dw->buf_size)
 265                 offset = 0;
 266         dw->buf_offset = offset;
 267 }
 268
 269 static void dw_hdmi_stop_dma(struct snd_dw_hdmi *dw)
 270 {
 271         /* Disable interrupts before disabling DMA */
 272         writeb_relaxed(~0, dw->data.base + HDMI_AHB_DMA_MASK);
 273         writeb_relaxed(HDMI_AHB_DMA_STOP_STOP, dw->data.base + HDMI_AHB_DMA_STOP);
 274 }
 275
 276 static irqreturn_t snd_dw_hdmi_irq(int irq, void *data)
 277 {
 278         struct snd_dw_hdmi *dw = data;
 279         struct snd_pcm_substream *substream;
 280         unsigned stat;
 281
 282         stat = readb_relaxed(dw->data.base + HDMI_IH_AHBDMAAUD_STAT0);
 283         if (!stat)
 284                 return IRQ_NONE;
 285
 286         writeb_relaxed(stat, dw->data.base + HDMI_IH_AHBDMAAUD_STAT0);
 287
 288         substream = dw->substream;
 289         if (stat & HDMI_IH_AHBDMAAUD_STAT0_DONE && substream) {
 290                 snd_pcm_period_elapsed(substream);
 291
 292                 spin_lock(&dw->lock);
 293                 if (dw->substream)
 294                         dw_hdmi_start_dma(dw);
 295                 spin_unlock(&dw->lock);
 296         }
 297
 298         return IRQ_HANDLED;
 299 }
 300
 301 static struct snd_pcm_hardware dw_hdmi_hw = {
 302         .info = SNDRV_PCM_INFO_INTERLEAVED |
 303                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
 304                 SNDRV_PCM_INFO_MMAP |
 305                 SNDRV_PCM_INFO_MMAP_VALID,
 306         .formats = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE |
 307                    SNDRV_PCM_FMTBIT_S24_LE,
 308         .rates = SNDRV_PCM_RATE_32000 |
 309                  SNDRV_PCM_RATE_44100 |
 310                  SNDRV_PCM_RATE_48000 |
 311                  SNDRV_PCM_RATE_88200 |
 312                  SNDRV_PCM_RATE_96000 |
 313                  SNDRV_PCM_RATE_176400 |
 314                  SNDRV_PCM_RATE_192000,
 315         .channels_min = 2,
 316         .channels_max = 8,
 317         .buffer_bytes_max = 64 * 1024,
 318         .period_bytes_min = 256,
 319         .period_bytes_max = 8192,       /* ERR004323: must limit to 8k */
 320         .periods_min = 2,
 321         .periods_max = 16,
 322         .fifo_size = 0,
 323 };
 324
 325 static int dw_hdmi_open(struct snd_pcm_substream *substream)
 326 {
 327         struct snd_pcm_runtime *runtime = substream->runtime;
 328         struct snd_dw_hdmi *dw = substream->private_data;
 329         void __iomem *base = dw->data.base;
 330         int ret;
 331
 332         runtime->hw = dw_hdmi_hw;
 333
 334         ret = snd_pcm_hw_constraint_eld(runtime, dw->data.eld);
 335         if (ret < 0)
 336                 return ret;
 337
 338         ret = snd_pcm_limit_hw_rates(runtime);
 339         if (ret < 0)
 340                 return ret;
 341
 342         ret = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
 343         if (ret < 0)
 344                 return ret;
 345
 346         /* Clear FIFO */
 347         writeb_relaxed(HDMI_AHB_DMA_CONF0_SW_FIFO_RST,
 348                        base + HDMI_AHB_DMA_CONF0);
 349
 350         /* Configure interrupt polarities */
 351         writeb_relaxed(~0, base + HDMI_AHB_DMA_POL);
 352         writeb_relaxed(~0, base + HDMI_AHB_DMA_BUFFPOL);
 353
 354         /* Keep interrupts masked, and clear any pending */
 355         writeb_relaxed(~0, base + HDMI_AHB_DMA_MASK);
 356         writeb_relaxed(~0, base + HDMI_IH_AHBDMAAUD_STAT0);
 357
 358         ret = request_irq(dw->data.irq, snd_dw_hdmi_irq, IRQF_SHARED,
 359                           "dw-hdmi-audio", dw);
 360         if (ret)
 361                 return ret;
 362
 363         /* Un-mute done interrupt */
 364         writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL &
 365                        ~HDMI_IH_MUTE_AHBDMAAUD_STAT0_DONE,
 366                        base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
 367
 368         return 0;
 369 }
 370
 371 static int dw_hdmi_close(struct snd_pcm_substream *substream)
 372 {
 373         struct snd_dw_hdmi *dw = substream->private_data;
 374
 375         /* Mute all interrupts */
 376         writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL,
 377                        dw->data.base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
 378
 379         free_irq(dw->data.irq, dw);
 380
 381         return 0;
 382 }
 383
 384 static int dw_hdmi_hw_free(struct snd_pcm_substream *substream)
 385 {
 386         return snd_pcm_lib_free_vmalloc_buffer(substream);
 387 }
 388
 389 static int dw_hdmi_hw_params(struct snd_pcm_substream *substream,
 390         struct snd_pcm_hw_params *params)
 391 {
 392         return snd_pcm_lib_alloc_vmalloc_buffer(substream,
 393                                                 params_buffer_bytes(params));
 394 }
 395
 396 static int dw_hdmi_prepare(struct snd_pcm_substream *substream)
 397 {
 398         struct snd_pcm_runtime *runtime = substream->runtime;
 399         struct snd_dw_hdmi *dw = substream->private_data;
 400         u8 threshold, conf0, conf1, layout, ca;
 401
 402         /* Setup as per 3.0.5 FSL 4.1.0 BSP */
 403         switch (dw->revision) {
 404         case 0x0a:
 405                 conf0 = HDMI_AHB_DMA_CONF0_BURST_MODE |
 406                         HDMI_AHB_DMA_CONF0_INCR4;
 407                 if (runtime->channels == 2)
 408                         threshold = 126;
 409                 else
 410                         threshold = 124;
 411                 break;
 412         case 0x1a:
 413                 conf0 = HDMI_AHB_DMA_CONF0_BURST_MODE |
 414                         HDMI_AHB_DMA_CONF0_INCR8;
 415                 threshold = 128;
 416                 break;
 417         default:
 418                 /* NOTREACHED */
 419                 return -EINVAL;
 420         }
 421
 422         dw_hdmi_set_sample_rate(dw->data.hdmi, runtime->rate);
 423
 424         /* Minimum number of bytes in the fifo. */
 425         runtime->hw.fifo_size = threshold * 32;
 426
 427         conf0 |= HDMI_AHB_DMA_CONF0_EN_HLOCK;
 428         conf1 = default_hdmi_channel_config[runtime->channels - 2].conf1;
 429         ca = default_hdmi_channel_config[runtime->channels - 2].ca;
 430
 431         /*
 432          * For >2 channel PCM audio, we need to select layout 1
 433          * and set an appropriate channel map.
 434          */
 435         if (runtime->channels > 2)
 436                 layout = HDMI_FC_AUDSCONF_LAYOUT1;
 437         else
 438                 layout = HDMI_FC_AUDSCONF_LAYOUT0;
 439
 440         writeb_relaxed(threshold, dw->data.base + HDMI_AHB_DMA_THRSLD);
 441         writeb_relaxed(conf0, dw->data.base + HDMI_AHB_DMA_CONF0);
 442         writeb_relaxed(conf1, dw->data.base + HDMI_AHB_DMA_CONF1);
 443         writeb_relaxed(layout, dw->data.base + HDMI_FC_AUDSCONF);
 444         writeb_relaxed(ca, dw->data.base + HDMI_FC_AUDICONF2);
 445
 446         switch (runtime->format) {
 447         case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
 448                 dw->reformat = dw_hdmi_reformat_iec958;
 449                 break;
 450         case SNDRV_PCM_FORMAT_S24_LE:
 451                 dw_hdmi_create_cs(dw, runtime);
 452                 dw->reformat = dw_hdmi_reformat_s24;
 453                 break;
 454         }
 455         dw->iec_offset = 0;
 456         dw->channels = runtime->channels;
 457         dw->buf_src  = runtime->dma_area;
 458         dw->buf_dst  = substream->dma_buffer.area;
 459         dw->buf_addr = substream->dma_buffer.addr;
 460         dw->buf_period = snd_pcm_lib_period_bytes(substream);
 461         dw->buf_size = snd_pcm_lib_buffer_bytes(substream);
 462
 463         return 0;
 464 }
 465
 466 static int dw_hdmi_trigger(struct snd_pcm_substream *substream, int cmd)
 467 {
 468         struct snd_dw_hdmi *dw = substream->private_data;
 469         unsigned long flags;
 470         int ret = 0;
 471
 472         switch (cmd) {
 473         case SNDRV_PCM_TRIGGER_START:
 474                 spin_lock_irqsave(&dw->lock, flags);
 475                 dw->buf_offset = 0;
 476                 dw->substream = substream;
 477                 dw_hdmi_start_dma(dw);
 478                 dw_hdmi_audio_enable(dw->data.hdmi);
 479                 spin_unlock_irqrestore(&dw->lock, flags);
 480                 substream->runtime->delay = substream->runtime->period_size;
 481                 break;
 482
 483         case SNDRV_PCM_TRIGGER_STOP:
 484                 spin_lock_irqsave(&dw->lock, flags);
 485                 dw->substream = NULL;
 486                 dw_hdmi_stop_dma(dw);
 487                 dw_hdmi_audio_disable(dw->data.hdmi);
 488                 spin_unlock_irqrestore(&dw->lock, flags);
 489                 break;
 490
 491         default:
 492                 ret = -EINVAL;
 493                 break;
 494         }
 495
 496         return ret;
 497 }
 498
 499 static snd_pcm_uframes_t dw_hdmi_pointer(struct snd_pcm_substream *substream)
 500 {
 501         struct snd_pcm_runtime *runtime = substream->runtime;
 502         struct snd_dw_hdmi *dw = substream->private_data;
 503
 504         /*
 505          * We are unable to report the exact hardware position as
 506          * reading the 32-bit DMA position using 8-bit reads is racy.
 507          */
 508         return bytes_to_frames(runtime, dw->buf_offset);
 509 }
 510
 511 static struct snd_pcm_ops snd_dw_hdmi_ops = {
 512         .open = dw_hdmi_open,
 513         .close = dw_hdmi_close,
 514         .ioctl = snd_pcm_lib_ioctl,
 515         .hw_params = dw_hdmi_hw_params,
 516         .hw_free = dw_hdmi_hw_free,
 517         .prepare = dw_hdmi_prepare,
 518         .trigger = dw_hdmi_trigger,
 519         .pointer = dw_hdmi_pointer,
 520         .page = snd_pcm_lib_get_vmalloc_page,
 521 };
 522
 523 static int snd_dw_hdmi_probe(struct platform_device *pdev)
 524 {
 525         const struct dw_hdmi_audio_data *data = pdev->dev.platform_data;
 526         struct device *dev = pdev->dev.parent;
 527         struct snd_dw_hdmi *dw;
 528         struct snd_card *card;
 529         struct snd_pcm *pcm;
 530         unsigned revision;
 531         int ret;
 532
 533         writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL,
 534                        data->base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
 535         revision = readb_relaxed(data->base + HDMI_REVISION_ID);
 536         if (revision != 0x0a && revision != 0x1a) {
 537                 dev_err(dev, "dw-hdmi-audio: unknown revision 0x%02x\n",
 538                         revision);
 539                 return -ENXIO;
 540         }
 541
 542         ret = snd_card_new(dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
 543                               THIS_MODULE, sizeof(struct snd_dw_hdmi), &card);
 544         if (ret < 0)
 545                 return ret;
 546
 547         strlcpy(card->driver, DRIVER_NAME, sizeof(card->driver));
 548         strlcpy(card->shortname, "DW-HDMI", sizeof(card->shortname));
 549         snprintf(card->longname, sizeof(card->longname),
 550                  "%s rev 0x%02x, irq %d", card->shortname, revision,
 551                  data->irq);
 552
 553         dw = card->private_data;
 554         dw->card = card;
 555         dw->data = *data;
 556         dw->revision = revision;
 557
 558         spin_lock_init(&dw->lock);
 559
 560         ret = snd_pcm_new(card, "DW HDMI", 0, 1, 0, &pcm);
 561         if (ret < 0)
 562                 goto err;
 563
 564         dw->pcm = pcm;
 565         pcm->private_data = dw;
 566         strlcpy(pcm->name, DRIVER_NAME, sizeof(pcm->name));
 567         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_dw_hdmi_ops);
 568
 569         snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
 570                         dev, 64 * 1024, 64 * 1024);
 571
 572         ret = snd_card_register(card);
 573         if (ret < 0)
 574                 goto err;
 575
 576         platform_set_drvdata(pdev, dw);
 577
 578         return 0;
 579
 580 err:
 581         snd_card_free(card);
 582         return ret;
 583 }
 584
 585 static int snd_dw_hdmi_remove(struct platform_device *pdev)
 586 {
 587         struct snd_dw_hdmi *dw = platform_get_drvdata(pdev);
 588
 589         snd_card_free(dw->card);
 590
 591         return 0;
 592 }
 593
 594 #if defined(CONFIG_PM_SLEEP) && defined(IS_NOT_BROKEN)
 595 /*
 596  * This code is fine, but requires implementation in the dw_hdmi_trigger()
 597  * method which is currently missing as I have no way to test this.
 598  */
 599 static int snd_dw_hdmi_suspend(struct device *dev)
 600 {
 601         struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
 602
 603         snd_power_change_state(dw->card, SNDRV_CTL_POWER_D3cold);
 604         snd_pcm_suspend_all(dw->pcm);
 605
 606         return 0;
 607 }
 608
 609 static int snd_dw_hdmi_resume(struct device *dev)
 610 {
 611         struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
 612
 613         snd_power_change_state(dw->card, SNDRV_CTL_POWER_D0);
 614
 615         return 0;
 616 }
 617
 618 static SIMPLE_DEV_PM_OPS(snd_dw_hdmi_pm, snd_dw_hdmi_suspend,
 619                          snd_dw_hdmi_resume);
 620 #define PM_OPS &snd_dw_hdmi_pm
 621 #else
 622 #define PM_OPS NULL
 623 #endif
 624
 625 static struct platform_driver snd_dw_hdmi_driver = {
 626         .probe  = snd_dw_hdmi_probe,
 627         .remove = snd_dw_hdmi_remove,
 628         .driver = {
 629                 .name = DRIVER_NAME,
 630                 .owner = THIS_MODULE,
 631                 .pm = PM_OPS,
 632         },
 633 };
 634
 635 module_platform_driver(snd_dw_hdmi_driver);
 636
 637 MODULE_AUTHOR("Russell King <rmk+kernel@arm.linux.org.uk>");
 638 MODULE_DESCRIPTION("Synopsis Designware HDMI AHB ALSA interface");
 639 MODULE_LICENSE("GPL v2");
 640 MODULE_ALIAS("platform:" DRIVER_NAME);