Linux 6.10-rc1
[sfrench/cifs-2.6.git] / drivers / gpu / drm / bridge / synopsys / dw-hdmi-ahb-audio.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * DesignWare HDMI audio driver
4  *
5  * Written and tested against the Designware HDMI Tx found in iMX6.
6  */
7 #include <linux/io.h>
8 #include <linux/interrupt.h>
9 #include <linux/module.h>
10 #include <linux/platform_device.h>
11 #include <drm/bridge/dw_hdmi.h>
12 #include <drm/drm_edid.h>
13
14 #include <sound/asoundef.h>
15 #include <sound/core.h>
16 #include <sound/initval.h>
17 #include <sound/pcm.h>
18 #include <sound/pcm_drm_eld.h>
19 #include <sound/pcm_iec958.h>
20
21 #include "dw-hdmi-audio.h"
22
23 #define DRIVER_NAME "dw-hdmi-ahb-audio"
24
25 /* Provide some bits rather than bit offsets */
26 enum {
27         HDMI_AHB_DMA_CONF0_SW_FIFO_RST = BIT(7),
28         HDMI_AHB_DMA_CONF0_EN_HLOCK = BIT(3),
29         HDMI_AHB_DMA_START_START = BIT(0),
30         HDMI_AHB_DMA_STOP_STOP = BIT(0),
31         HDMI_IH_MUTE_AHBDMAAUD_STAT0_ERROR = BIT(5),
32         HDMI_IH_MUTE_AHBDMAAUD_STAT0_LOST = BIT(4),
33         HDMI_IH_MUTE_AHBDMAAUD_STAT0_RETRY = BIT(3),
34         HDMI_IH_MUTE_AHBDMAAUD_STAT0_DONE = BIT(2),
35         HDMI_IH_MUTE_AHBDMAAUD_STAT0_BUFFFULL = BIT(1),
36         HDMI_IH_MUTE_AHBDMAAUD_STAT0_BUFFEMPTY = BIT(0),
37         HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL =
38                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_ERROR |
39                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_LOST |
40                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_RETRY |
41                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_DONE |
42                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_BUFFFULL |
43                 HDMI_IH_MUTE_AHBDMAAUD_STAT0_BUFFEMPTY,
44         HDMI_IH_AHBDMAAUD_STAT0_ERROR = BIT(5),
45         HDMI_IH_AHBDMAAUD_STAT0_LOST = BIT(4),
46         HDMI_IH_AHBDMAAUD_STAT0_RETRY = BIT(3),
47         HDMI_IH_AHBDMAAUD_STAT0_DONE = BIT(2),
48         HDMI_IH_AHBDMAAUD_STAT0_BUFFFULL = BIT(1),
49         HDMI_IH_AHBDMAAUD_STAT0_BUFFEMPTY = BIT(0),
50         HDMI_IH_AHBDMAAUD_STAT0_ALL =
51                 HDMI_IH_AHBDMAAUD_STAT0_ERROR |
52                 HDMI_IH_AHBDMAAUD_STAT0_LOST |
53                 HDMI_IH_AHBDMAAUD_STAT0_RETRY |
54                 HDMI_IH_AHBDMAAUD_STAT0_DONE |
55                 HDMI_IH_AHBDMAAUD_STAT0_BUFFFULL |
56                 HDMI_IH_AHBDMAAUD_STAT0_BUFFEMPTY,
57         HDMI_AHB_DMA_CONF0_INCR16 = 2 << 1,
58         HDMI_AHB_DMA_CONF0_INCR8 = 1 << 1,
59         HDMI_AHB_DMA_CONF0_INCR4 = 0,
60         HDMI_AHB_DMA_CONF0_BURST_MODE = BIT(0),
61         HDMI_AHB_DMA_MASK_DONE = BIT(7),
62
63         HDMI_REVISION_ID = 0x0001,
64         HDMI_IH_AHBDMAAUD_STAT0 = 0x0109,
65         HDMI_IH_MUTE_AHBDMAAUD_STAT0 = 0x0189,
66         HDMI_AHB_DMA_CONF0 = 0x3600,
67         HDMI_AHB_DMA_START = 0x3601,
68         HDMI_AHB_DMA_STOP = 0x3602,
69         HDMI_AHB_DMA_THRSLD = 0x3603,
70         HDMI_AHB_DMA_STRADDR0 = 0x3604,
71         HDMI_AHB_DMA_STPADDR0 = 0x3608,
72         HDMI_AHB_DMA_MASK = 0x3614,
73         HDMI_AHB_DMA_POL = 0x3615,
74         HDMI_AHB_DMA_CONF1 = 0x3616,
75         HDMI_AHB_DMA_BUFFPOL = 0x361a,
76 };
77
78 struct dw_hdmi_channel_conf {
79         u8 conf1;
80         u8 ca;
81 };
82
83 /*
84  * The default mapping of ALSA channels to HDMI channels and speaker
85  * allocation bits.  Note that we can't do channel remapping here -
86  * channels must be in the same order.
87  *
88  * Mappings for alsa-lib pcm/surround*.conf files:
89  *
90  *              Front   Sur4.0  Sur4.1  Sur5.0  Sur5.1  Sur7.1
91  * Channels     2       4       6       6       6       8
92  *
93  * Our mapping from ALSA channel to CEA686D speaker name and HDMI channel:
94  *
95  *                              Number of ALSA channels
96  * ALSA Channel 2       3       4       5       6       7       8
97  * 0            FL:0    =       =       =       =       =       =
98  * 1            FR:1    =       =       =       =       =       =
99  * 2                    FC:3    RL:4    LFE:2   =       =       =
100  * 3                            RR:5    RL:4    FC:3    =       =
101  * 4                                    RR:5    RL:4    =       =
102  * 5                                            RR:5    =       =
103  * 6                                                    RC:6    =
104  * 7                                                    RLC/FRC RLC/FRC
105  */
106 static struct dw_hdmi_channel_conf default_hdmi_channel_config[7] = {
107         { 0x03, 0x00 }, /* FL,FR */
108         { 0x0b, 0x02 }, /* FL,FR,FC */
109         { 0x33, 0x08 }, /* FL,FR,RL,RR */
110         { 0x37, 0x09 }, /* FL,FR,LFE,RL,RR */
111         { 0x3f, 0x0b }, /* FL,FR,LFE,FC,RL,RR */
112         { 0x7f, 0x0f }, /* FL,FR,LFE,FC,RL,RR,RC */
113         { 0xff, 0x13 }, /* FL,FR,LFE,FC,RL,RR,[FR]RC,[FR]LC */
114 };
115
116 struct snd_dw_hdmi {
117         struct snd_card *card;
118         struct snd_pcm *pcm;
119         spinlock_t lock;
120         struct dw_hdmi_audio_data data;
121         struct snd_pcm_substream *substream;
122         void (*reformat)(struct snd_dw_hdmi *, size_t, size_t);
123         void *buf_src;
124         void *buf_dst;
125         dma_addr_t buf_addr;
126         unsigned buf_offset;
127         unsigned buf_period;
128         unsigned buf_size;
129         unsigned channels;
130         u8 revision;
131         u8 iec_offset;
132         u8 cs[192][8];
133 };
134
135 static void dw_hdmi_writel(u32 val, void __iomem *ptr)
136 {
137         writeb_relaxed(val, ptr);
138         writeb_relaxed(val >> 8, ptr + 1);
139         writeb_relaxed(val >> 16, ptr + 2);
140         writeb_relaxed(val >> 24, ptr + 3);
141 }
142
143 /*
144  * Convert to hardware format: The userspace buffer contains IEC958 samples,
145  * with the PCUV bits in bits 31..28 and audio samples in bits 27..4.  We
146  * need these to be in bits 27..24, with the IEC B bit in bit 28, and audio
147  * samples in 23..0.
148  *
149  * Default preamble in bits 3..0: 8 = block start, 4 = even 2 = odd
150  *
151  * Ideally, we could do with having the data properly formatted in userspace.
152  */
153 static void dw_hdmi_reformat_iec958(struct snd_dw_hdmi *dw,
154         size_t offset, size_t bytes)
155 {
156         u32 *src = dw->buf_src + offset;
157         u32 *dst = dw->buf_dst + offset;
158         u32 *end = dw->buf_src + offset + bytes;
159
160         do {
161                 u32 b, sample = *src++;
162
163                 b = (sample & 8) << (28 - 3);
164
165                 sample >>= 4;
166
167                 *dst++ = sample | b;
168         } while (src < end);
169 }
170
171 static u32 parity(u32 sample)
172 {
173         sample ^= sample >> 16;
174         sample ^= sample >> 8;
175         sample ^= sample >> 4;
176         sample ^= sample >> 2;
177         sample ^= sample >> 1;
178         return (sample & 1) << 27;
179 }
180
181 static void dw_hdmi_reformat_s24(struct snd_dw_hdmi *dw,
182         size_t offset, size_t bytes)
183 {
184         u32 *src = dw->buf_src + offset;
185         u32 *dst = dw->buf_dst + offset;
186         u32 *end = dw->buf_src + offset + bytes;
187
188         do {
189                 unsigned i;
190                 u8 *cs;
191
192                 cs = dw->cs[dw->iec_offset++];
193                 if (dw->iec_offset >= 192)
194                         dw->iec_offset = 0;
195
196                 i = dw->channels;
197                 do {
198                         u32 sample = *src++;
199
200                         sample &= ~0xff000000;
201                         sample |= *cs++ << 24;
202                         sample |= parity(sample & ~0xf8000000);
203
204                         *dst++ = sample;
205                 } while (--i);
206         } while (src < end);
207 }
208
209 static void dw_hdmi_create_cs(struct snd_dw_hdmi *dw,
210         struct snd_pcm_runtime *runtime)
211 {
212         u8 cs[4];
213         unsigned ch, i, j;
214
215         snd_pcm_create_iec958_consumer(runtime, cs, sizeof(cs));
216
217         memset(dw->cs, 0, sizeof(dw->cs));
218
219         for (ch = 0; ch < 8; ch++) {
220                 cs[2] &= ~IEC958_AES2_CON_CHANNEL;
221                 cs[2] |= (ch + 1) << 4;
222
223                 for (i = 0; i < ARRAY_SIZE(cs); i++) {
224                         unsigned c = cs[i];
225
226                         for (j = 0; j < 8; j++, c >>= 1)
227                                 dw->cs[i * 8 + j][ch] = (c & 1) << 2;
228                 }
229         }
230         dw->cs[0][0] |= BIT(4);
231 }
232
233 static void dw_hdmi_start_dma(struct snd_dw_hdmi *dw)
234 {
235         void __iomem *base = dw->data.base;
236         unsigned offset = dw->buf_offset;
237         unsigned period = dw->buf_period;
238         u32 start, stop;
239
240         dw->reformat(dw, offset, period);
241
242         /* Clear all irqs before enabling irqs and starting DMA */
243         writeb_relaxed(HDMI_IH_AHBDMAAUD_STAT0_ALL,
244                        base + HDMI_IH_AHBDMAAUD_STAT0);
245
246         start = dw->buf_addr + offset;
247         stop = start + period - 1;
248
249         /* Setup the hardware start/stop addresses */
250         dw_hdmi_writel(start, base + HDMI_AHB_DMA_STRADDR0);
251         dw_hdmi_writel(stop, base + HDMI_AHB_DMA_STPADDR0);
252
253         writeb_relaxed((u8)~HDMI_AHB_DMA_MASK_DONE, base + HDMI_AHB_DMA_MASK);
254         writeb(HDMI_AHB_DMA_START_START, base + HDMI_AHB_DMA_START);
255
256         offset += period;
257         if (offset >= dw->buf_size)
258                 offset = 0;
259         dw->buf_offset = offset;
260 }
261
262 static void dw_hdmi_stop_dma(struct snd_dw_hdmi *dw)
263 {
264         /* Disable interrupts before disabling DMA */
265         writeb_relaxed(~0, dw->data.base + HDMI_AHB_DMA_MASK);
266         writeb_relaxed(HDMI_AHB_DMA_STOP_STOP, dw->data.base + HDMI_AHB_DMA_STOP);
267 }
268
269 static irqreturn_t snd_dw_hdmi_irq(int irq, void *data)
270 {
271         struct snd_dw_hdmi *dw = data;
272         struct snd_pcm_substream *substream;
273         unsigned stat;
274
275         stat = readb_relaxed(dw->data.base + HDMI_IH_AHBDMAAUD_STAT0);
276         if (!stat)
277                 return IRQ_NONE;
278
279         writeb_relaxed(stat, dw->data.base + HDMI_IH_AHBDMAAUD_STAT0);
280
281         substream = dw->substream;
282         if (stat & HDMI_IH_AHBDMAAUD_STAT0_DONE && substream) {
283                 snd_pcm_period_elapsed(substream);
284
285                 spin_lock(&dw->lock);
286                 if (dw->substream)
287                         dw_hdmi_start_dma(dw);
288                 spin_unlock(&dw->lock);
289         }
290
291         return IRQ_HANDLED;
292 }
293
294 static const struct snd_pcm_hardware dw_hdmi_hw = {
295         .info = SNDRV_PCM_INFO_INTERLEAVED |
296                 SNDRV_PCM_INFO_BLOCK_TRANSFER |
297                 SNDRV_PCM_INFO_MMAP |
298                 SNDRV_PCM_INFO_MMAP_VALID,
299         .formats = SNDRV_PCM_FMTBIT_IEC958_SUBFRAME_LE |
300                    SNDRV_PCM_FMTBIT_S24_LE,
301         .rates = SNDRV_PCM_RATE_32000 |
302                  SNDRV_PCM_RATE_44100 |
303                  SNDRV_PCM_RATE_48000 |
304                  SNDRV_PCM_RATE_88200 |
305                  SNDRV_PCM_RATE_96000 |
306                  SNDRV_PCM_RATE_176400 |
307                  SNDRV_PCM_RATE_192000,
308         .channels_min = 2,
309         .channels_max = 8,
310         .buffer_bytes_max = 1024 * 1024,
311         .period_bytes_min = 256,
312         .period_bytes_max = 8192,       /* ERR004323: must limit to 8k */
313         .periods_min = 2,
314         .periods_max = 16,
315         .fifo_size = 0,
316 };
317
318 static int dw_hdmi_open(struct snd_pcm_substream *substream)
319 {
320         struct snd_pcm_runtime *runtime = substream->runtime;
321         struct snd_dw_hdmi *dw = substream->private_data;
322         void __iomem *base = dw->data.base;
323         u8 *eld;
324         int ret;
325
326         runtime->hw = dw_hdmi_hw;
327
328         eld = dw->data.get_eld(dw->data.hdmi);
329         if (eld) {
330                 ret = snd_pcm_hw_constraint_eld(runtime, eld);
331                 if (ret < 0)
332                         return ret;
333         }
334
335         ret = snd_pcm_limit_hw_rates(runtime);
336         if (ret < 0)
337                 return ret;
338
339         ret = snd_pcm_hw_constraint_integer(runtime,
340                                             SNDRV_PCM_HW_PARAM_PERIODS);
341         if (ret < 0)
342                 return ret;
343
344         /* Limit the buffer size to the size of the preallocated buffer */
345         ret = snd_pcm_hw_constraint_minmax(runtime,
346                                            SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
347                                            0, substream->dma_buffer.bytes);
348         if (ret < 0)
349                 return ret;
350
351         /* Clear FIFO */
352         writeb_relaxed(HDMI_AHB_DMA_CONF0_SW_FIFO_RST,
353                        base + HDMI_AHB_DMA_CONF0);
354
355         /* Configure interrupt polarities */
356         writeb_relaxed(~0, base + HDMI_AHB_DMA_POL);
357         writeb_relaxed(~0, base + HDMI_AHB_DMA_BUFFPOL);
358
359         /* Keep interrupts masked, and clear any pending */
360         writeb_relaxed(~0, base + HDMI_AHB_DMA_MASK);
361         writeb_relaxed(~0, base + HDMI_IH_AHBDMAAUD_STAT0);
362
363         ret = request_irq(dw->data.irq, snd_dw_hdmi_irq, IRQF_SHARED,
364                           "dw-hdmi-audio", dw);
365         if (ret)
366                 return ret;
367
368         /* Un-mute done interrupt */
369         writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL &
370                        ~HDMI_IH_MUTE_AHBDMAAUD_STAT0_DONE,
371                        base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
372
373         return 0;
374 }
375
376 static int dw_hdmi_close(struct snd_pcm_substream *substream)
377 {
378         struct snd_dw_hdmi *dw = substream->private_data;
379
380         /* Mute all interrupts */
381         writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL,
382                        dw->data.base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
383
384         free_irq(dw->data.irq, dw);
385
386         return 0;
387 }
388
389 static int dw_hdmi_hw_free(struct snd_pcm_substream *substream)
390 {
391         return snd_pcm_lib_free_vmalloc_buffer(substream);
392 }
393
394 static int dw_hdmi_hw_params(struct snd_pcm_substream *substream,
395         struct snd_pcm_hw_params *params)
396 {
397         /* Allocate the PCM runtime buffer, which is exposed to userspace. */
398         return snd_pcm_lib_alloc_vmalloc_buffer(substream,
399                                                 params_buffer_bytes(params));
400 }
401
402 static int dw_hdmi_prepare(struct snd_pcm_substream *substream)
403 {
404         struct snd_pcm_runtime *runtime = substream->runtime;
405         struct snd_dw_hdmi *dw = substream->private_data;
406         u8 threshold, conf0, conf1, ca;
407
408         /* Setup as per 3.0.5 FSL 4.1.0 BSP */
409         switch (dw->revision) {
410         case 0x0a:
411                 conf0 = HDMI_AHB_DMA_CONF0_BURST_MODE |
412                         HDMI_AHB_DMA_CONF0_INCR4;
413                 if (runtime->channels == 2)
414                         threshold = 126;
415                 else
416                         threshold = 124;
417                 break;
418         case 0x1a:
419                 conf0 = HDMI_AHB_DMA_CONF0_BURST_MODE |
420                         HDMI_AHB_DMA_CONF0_INCR8;
421                 threshold = 128;
422                 break;
423         default:
424                 /* NOTREACHED */
425                 return -EINVAL;
426         }
427
428         dw_hdmi_set_sample_rate(dw->data.hdmi, runtime->rate);
429
430         /* Minimum number of bytes in the fifo. */
431         runtime->hw.fifo_size = threshold * 32;
432
433         conf0 |= HDMI_AHB_DMA_CONF0_EN_HLOCK;
434         conf1 = default_hdmi_channel_config[runtime->channels - 2].conf1;
435         ca = default_hdmi_channel_config[runtime->channels - 2].ca;
436
437         writeb_relaxed(threshold, dw->data.base + HDMI_AHB_DMA_THRSLD);
438         writeb_relaxed(conf0, dw->data.base + HDMI_AHB_DMA_CONF0);
439         writeb_relaxed(conf1, dw->data.base + HDMI_AHB_DMA_CONF1);
440
441         dw_hdmi_set_channel_count(dw->data.hdmi, runtime->channels);
442         dw_hdmi_set_channel_allocation(dw->data.hdmi, ca);
443
444         switch (runtime->format) {
445         case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
446                 dw->reformat = dw_hdmi_reformat_iec958;
447                 break;
448         case SNDRV_PCM_FORMAT_S24_LE:
449                 dw_hdmi_create_cs(dw, runtime);
450                 dw->reformat = dw_hdmi_reformat_s24;
451                 break;
452         }
453         dw->iec_offset = 0;
454         dw->channels = runtime->channels;
455         dw->buf_src  = runtime->dma_area;
456         dw->buf_dst  = substream->dma_buffer.area;
457         dw->buf_addr = substream->dma_buffer.addr;
458         dw->buf_period = snd_pcm_lib_period_bytes(substream);
459         dw->buf_size = snd_pcm_lib_buffer_bytes(substream);
460
461         return 0;
462 }
463
464 static int dw_hdmi_trigger(struct snd_pcm_substream *substream, int cmd)
465 {
466         struct snd_dw_hdmi *dw = substream->private_data;
467         unsigned long flags;
468         int ret = 0;
469
470         switch (cmd) {
471         case SNDRV_PCM_TRIGGER_START:
472                 spin_lock_irqsave(&dw->lock, flags);
473                 dw->buf_offset = 0;
474                 dw->substream = substream;
475                 dw_hdmi_start_dma(dw);
476                 dw_hdmi_audio_enable(dw->data.hdmi);
477                 spin_unlock_irqrestore(&dw->lock, flags);
478                 substream->runtime->delay = substream->runtime->period_size;
479                 break;
480
481         case SNDRV_PCM_TRIGGER_STOP:
482                 spin_lock_irqsave(&dw->lock, flags);
483                 dw->substream = NULL;
484                 dw_hdmi_stop_dma(dw);
485                 dw_hdmi_audio_disable(dw->data.hdmi);
486                 spin_unlock_irqrestore(&dw->lock, flags);
487                 break;
488
489         default:
490                 ret = -EINVAL;
491                 break;
492         }
493
494         return ret;
495 }
496
497 static snd_pcm_uframes_t dw_hdmi_pointer(struct snd_pcm_substream *substream)
498 {
499         struct snd_pcm_runtime *runtime = substream->runtime;
500         struct snd_dw_hdmi *dw = substream->private_data;
501
502         /*
503          * We are unable to report the exact hardware position as
504          * reading the 32-bit DMA position using 8-bit reads is racy.
505          */
506         return bytes_to_frames(runtime, dw->buf_offset);
507 }
508
509 static const struct snd_pcm_ops snd_dw_hdmi_ops = {
510         .open = dw_hdmi_open,
511         .close = dw_hdmi_close,
512         .ioctl = snd_pcm_lib_ioctl,
513         .hw_params = dw_hdmi_hw_params,
514         .hw_free = dw_hdmi_hw_free,
515         .prepare = dw_hdmi_prepare,
516         .trigger = dw_hdmi_trigger,
517         .pointer = dw_hdmi_pointer,
518         .page = snd_pcm_lib_get_vmalloc_page,
519 };
520
521 static int snd_dw_hdmi_probe(struct platform_device *pdev)
522 {
523         const struct dw_hdmi_audio_data *data = pdev->dev.platform_data;
524         struct device *dev = pdev->dev.parent;
525         struct snd_dw_hdmi *dw;
526         struct snd_card *card;
527         struct snd_pcm *pcm;
528         unsigned revision;
529         int ret;
530
531         writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL,
532                        data->base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
533         revision = readb_relaxed(data->base + HDMI_REVISION_ID);
534         if (revision != 0x0a && revision != 0x1a) {
535                 dev_err(dev, "dw-hdmi-audio: unknown revision 0x%02x\n",
536                         revision);
537                 return -ENXIO;
538         }
539
540         ret = snd_card_new(dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
541                               THIS_MODULE, sizeof(struct snd_dw_hdmi), &card);
542         if (ret < 0)
543                 return ret;
544
545         strscpy(card->driver, DRIVER_NAME, sizeof(card->driver));
546         strscpy(card->shortname, "DW-HDMI", sizeof(card->shortname));
547         snprintf(card->longname, sizeof(card->longname),
548                  "%s rev 0x%02x, irq %d", card->shortname, revision,
549                  data->irq);
550
551         dw = card->private_data;
552         dw->card = card;
553         dw->data = *data;
554         dw->revision = revision;
555
556         spin_lock_init(&dw->lock);
557
558         ret = snd_pcm_new(card, "DW HDMI", 0, 1, 0, &pcm);
559         if (ret < 0)
560                 goto err;
561
562         dw->pcm = pcm;
563         pcm->private_data = dw;
564         strscpy(pcm->name, DRIVER_NAME, sizeof(pcm->name));
565         snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_dw_hdmi_ops);
566
567         /*
568          * To support 8-channel 96kHz audio reliably, we need 512k
569          * to satisfy alsa with our restricted period (ERR004323).
570          */
571         snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
572                         dev, 128 * 1024, 1024 * 1024);
573
574         ret = snd_card_register(card);
575         if (ret < 0)
576                 goto err;
577
578         platform_set_drvdata(pdev, dw);
579
580         return 0;
581
582 err:
583         snd_card_free(card);
584         return ret;
585 }
586
587 static void snd_dw_hdmi_remove(struct platform_device *pdev)
588 {
589         struct snd_dw_hdmi *dw = platform_get_drvdata(pdev);
590
591         snd_card_free(dw->card);
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
605         return 0;
606 }
607
608 static int snd_dw_hdmi_resume(struct device *dev)
609 {
610         struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
611
612         snd_power_change_state(dw->card, SNDRV_CTL_POWER_D0);
613
614         return 0;
615 }
616
617 static SIMPLE_DEV_PM_OPS(snd_dw_hdmi_pm, snd_dw_hdmi_suspend,
618                          snd_dw_hdmi_resume);
619 #define PM_OPS &snd_dw_hdmi_pm
620 #else
621 #define PM_OPS NULL
622 #endif
623
624 static struct platform_driver snd_dw_hdmi_driver = {
625         .probe  = snd_dw_hdmi_probe,
626         .remove_new = snd_dw_hdmi_remove,
627         .driver = {
628                 .name = DRIVER_NAME,
629                 .pm = PM_OPS,
630         },
631 };
632
633 module_platform_driver(snd_dw_hdmi_driver);
634
635 MODULE_AUTHOR("Russell King <rmk+kernel@armlinux.org.uk>");
636 MODULE_DESCRIPTION("Synopsis Designware HDMI AHB ALSA interface");
637 MODULE_LICENSE("GPL v2");
638 MODULE_ALIAS("platform:" DRIVER_NAME);