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 */
26enum {
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
78struct 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 */
106static 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
116struct 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
135static 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 */
153static 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
171static 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
181static 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: sample & ~0xf8000000);
203
204 *dst++ = sample;
205 } while (--i);
206 } while (src < end);
207}
208
209static 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, len: 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
233static 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(val: start, ptr: base + HDMI_AHB_DMA_STRADDR0);
251 dw_hdmi_writel(val: stop, ptr: base + HDMI_AHB_DMA_STPADDR0);
252
253 writeb_relaxed((u8)~HDMI_AHB_DMA_MASK_DONE, base + HDMI_AHB_DMA_MASK);
254 writeb(val: HDMI_AHB_DMA_START_START, addr: 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
262static 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
269static 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(lock: &dw->lock);
286 if (dw->substream)
287 dw_hdmi_start_dma(dw);
288 spin_unlock(lock: &dw->lock);
289 }
290
291 return IRQ_HANDLED;
292}
293
294static 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
318static 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 min: 0, max: 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(irq: dw->data.irq, handler: snd_dw_hdmi_irq, IRQF_SHARED,
364 name: "dw-hdmi-audio", dev: 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
376static 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
389static int dw_hdmi_hw_free(struct snd_pcm_substream *substream)
390{
391 return snd_pcm_lib_free_vmalloc_buffer(substream);
392}
393
394static 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 size: params_buffer_bytes(p: params));
400}
401
402static 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(hdmi: dw->data.hdmi, rate: 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(hdmi: dw->data.hdmi, cnt: runtime->channels);
442 dw_hdmi_set_channel_allocation(hdmi: 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
464static 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(hdmi: dw->data.hdmi);
477 spin_unlock_irqrestore(lock: &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(hdmi: dw->data.hdmi);
486 spin_unlock_irqrestore(lock: &dw->lock, flags);
487 break;
488
489 default:
490 ret = -EINVAL;
491 break;
492 }
493
494 return ret;
495}
496
497static 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, size: dw->buf_offset);
507}
508
509static 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
521static 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(parent: dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
541 THIS_MODULE, extra_size: sizeof(struct snd_dw_hdmi), card_ret: &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(buf: card->longname, size: sizeof(card->longname),
548 fmt: "%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, id: "DW HDMI", device: 0, playback_count: 1, capture_count: 0, rpcm: &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, direction: SNDRV_PCM_STREAM_PLAYBACK, ops: &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 data: dev, size: 128 * 1024, max: 1024 * 1024);
573
574 ret = snd_card_register(card);
575 if (ret < 0)
576 goto err;
577
578 platform_set_drvdata(pdev, data: dw);
579
580 return 0;
581
582err:
583 snd_card_free(card);
584 return ret;
585}
586
587static 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(card: 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 */
599static 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
608static 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
617static 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
624static 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
633module_platform_driver(snd_dw_hdmi_driver);
634
635MODULE_AUTHOR("Russell King <rmk+kernel@armlinux.org.uk>");
636MODULE_DESCRIPTION("Synopsis Designware HDMI AHB ALSA interface");
637MODULE_LICENSE("GPL v2");
638MODULE_ALIAS("platform:" DRIVER_NAME);
639

source code of linux/drivers/gpu/drm/bridge/synopsys/dw-hdmi-ahb-audio.c