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  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 & ~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, 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(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
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(&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
294static 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	int ret;
324
325	runtime->hw = dw_hdmi_hw;
326
327	ret = snd_pcm_hw_constraint_eld(runtime, dw->data.eld);
328	if (ret < 0)
329		return ret;
330
331	ret = snd_pcm_limit_hw_rates(runtime);
332	if (ret < 0)
333		return ret;
334
335	ret = snd_pcm_hw_constraint_integer(runtime,
336					    SNDRV_PCM_HW_PARAM_PERIODS);
337	if (ret < 0)
338		return ret;
339
340	/* Limit the buffer size to the size of the preallocated buffer */
341	ret = snd_pcm_hw_constraint_minmax(runtime,
342					   SNDRV_PCM_HW_PARAM_BUFFER_SIZE,
343					   0, substream->dma_buffer.bytes);
344	if (ret < 0)
345		return ret;
346
347	/* Clear FIFO */
348	writeb_relaxed(HDMI_AHB_DMA_CONF0_SW_FIFO_RST,
349		       base + HDMI_AHB_DMA_CONF0);
350
351	/* Configure interrupt polarities */
352	writeb_relaxed(~0, base + HDMI_AHB_DMA_POL);
353	writeb_relaxed(~0, base + HDMI_AHB_DMA_BUFFPOL);
354
355	/* Keep interrupts masked, and clear any pending */
356	writeb_relaxed(~0, base + HDMI_AHB_DMA_MASK);
357	writeb_relaxed(~0, base + HDMI_IH_AHBDMAAUD_STAT0);
358
359	ret = request_irq(dw->data.irq, snd_dw_hdmi_irq, IRQF_SHARED,
360			  "dw-hdmi-audio", dw);
361	if (ret)
362		return ret;
363
364	/* Un-mute done interrupt */
365	writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL &
366		       ~HDMI_IH_MUTE_AHBDMAAUD_STAT0_DONE,
367		       base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
368
369	return 0;
370}
371
372static int dw_hdmi_close(struct snd_pcm_substream *substream)
373{
374	struct snd_dw_hdmi *dw = substream->private_data;
375
376	/* Mute all interrupts */
377	writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL,
378		       dw->data.base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
379
380	free_irq(dw->data.irq, dw);
381
382	return 0;
383}
384
385static int dw_hdmi_hw_free(struct snd_pcm_substream *substream)
386{
387	return snd_pcm_lib_free_vmalloc_buffer(substream);
388}
389
390static int dw_hdmi_hw_params(struct snd_pcm_substream *substream,
391	struct snd_pcm_hw_params *params)
392{
393	/* Allocate the PCM runtime buffer, which is exposed to userspace. */
394	return snd_pcm_lib_alloc_vmalloc_buffer(substream,
395						params_buffer_bytes(params));
396}
397
398static int dw_hdmi_prepare(struct snd_pcm_substream *substream)
399{
400	struct snd_pcm_runtime *runtime = substream->runtime;
401	struct snd_dw_hdmi *dw = substream->private_data;
402	u8 threshold, conf0, conf1, ca;
403
404	/* Setup as per 3.0.5 FSL 4.1.0 BSP */
405	switch (dw->revision) {
406	case 0x0a:
407		conf0 = HDMI_AHB_DMA_CONF0_BURST_MODE |
408			HDMI_AHB_DMA_CONF0_INCR4;
409		if (runtime->channels == 2)
410			threshold = 126;
411		else
412			threshold = 124;
413		break;
414	case 0x1a:
415		conf0 = HDMI_AHB_DMA_CONF0_BURST_MODE |
416			HDMI_AHB_DMA_CONF0_INCR8;
417		threshold = 128;
418		break;
419	default:
420		/* NOTREACHED */
421		return -EINVAL;
422	}
423
424	dw_hdmi_set_sample_rate(dw->data.hdmi, runtime->rate);
425
426	/* Minimum number of bytes in the fifo. */
427	runtime->hw.fifo_size = threshold * 32;
428
429	conf0 |= HDMI_AHB_DMA_CONF0_EN_HLOCK;
430	conf1 = default_hdmi_channel_config[runtime->channels - 2].conf1;
431	ca = default_hdmi_channel_config[runtime->channels - 2].ca;
432
433	writeb_relaxed(threshold, dw->data.base + HDMI_AHB_DMA_THRSLD);
434	writeb_relaxed(conf0, dw->data.base + HDMI_AHB_DMA_CONF0);
435	writeb_relaxed(conf1, dw->data.base + HDMI_AHB_DMA_CONF1);
436
437	dw_hdmi_set_channel_count(dw->data.hdmi, runtime->channels);
438	dw_hdmi_set_channel_allocation(dw->data.hdmi, ca);
439
440	switch (runtime->format) {
441	case SNDRV_PCM_FORMAT_IEC958_SUBFRAME_LE:
442		dw->reformat = dw_hdmi_reformat_iec958;
443		break;
444	case SNDRV_PCM_FORMAT_S24_LE:
445		dw_hdmi_create_cs(dw, runtime);
446		dw->reformat = dw_hdmi_reformat_s24;
447		break;
448	}
449	dw->iec_offset = 0;
450	dw->channels = runtime->channels;
451	dw->buf_src  = runtime->dma_area;
452	dw->buf_dst  = substream->dma_buffer.area;
453	dw->buf_addr = substream->dma_buffer.addr;
454	dw->buf_period = snd_pcm_lib_period_bytes(substream);
455	dw->buf_size = snd_pcm_lib_buffer_bytes(substream);
456
457	return 0;
458}
459
460static int dw_hdmi_trigger(struct snd_pcm_substream *substream, int cmd)
461{
462	struct snd_dw_hdmi *dw = substream->private_data;
463	unsigned long flags;
464	int ret = 0;
465
466	switch (cmd) {
467	case SNDRV_PCM_TRIGGER_START:
468		spin_lock_irqsave(&dw->lock, flags);
469		dw->buf_offset = 0;
470		dw->substream = substream;
471		dw_hdmi_start_dma(dw);
472		dw_hdmi_audio_enable(dw->data.hdmi);
473		spin_unlock_irqrestore(&dw->lock, flags);
474		substream->runtime->delay = substream->runtime->period_size;
475		break;
476
477	case SNDRV_PCM_TRIGGER_STOP:
478		spin_lock_irqsave(&dw->lock, flags);
479		dw->substream = NULL;
480		dw_hdmi_stop_dma(dw);
481		dw_hdmi_audio_disable(dw->data.hdmi);
482		spin_unlock_irqrestore(&dw->lock, flags);
483		break;
484
485	default:
486		ret = -EINVAL;
487		break;
488	}
489
490	return ret;
491}
492
493static snd_pcm_uframes_t dw_hdmi_pointer(struct snd_pcm_substream *substream)
494{
495	struct snd_pcm_runtime *runtime = substream->runtime;
496	struct snd_dw_hdmi *dw = substream->private_data;
497
498	/*
499	 * We are unable to report the exact hardware position as
500	 * reading the 32-bit DMA position using 8-bit reads is racy.
501	 */
502	return bytes_to_frames(runtime, dw->buf_offset);
503}
504
505static const struct snd_pcm_ops snd_dw_hdmi_ops = {
506	.open = dw_hdmi_open,
507	.close = dw_hdmi_close,
508	.ioctl = snd_pcm_lib_ioctl,
509	.hw_params = dw_hdmi_hw_params,
510	.hw_free = dw_hdmi_hw_free,
511	.prepare = dw_hdmi_prepare,
512	.trigger = dw_hdmi_trigger,
513	.pointer = dw_hdmi_pointer,
514	.page = snd_pcm_lib_get_vmalloc_page,
515};
516
517static int snd_dw_hdmi_probe(struct platform_device *pdev)
518{
519	const struct dw_hdmi_audio_data *data = pdev->dev.platform_data;
520	struct device *dev = pdev->dev.parent;
521	struct snd_dw_hdmi *dw;
522	struct snd_card *card;
523	struct snd_pcm *pcm;
524	unsigned revision;
525	int ret;
526
527	writeb_relaxed(HDMI_IH_MUTE_AHBDMAAUD_STAT0_ALL,
528		       data->base + HDMI_IH_MUTE_AHBDMAAUD_STAT0);
529	revision = readb_relaxed(data->base + HDMI_REVISION_ID);
530	if (revision != 0x0a && revision != 0x1a) {
531		dev_err(dev, "dw-hdmi-audio: unknown revision 0x%02x\n",
532			revision);
533		return -ENXIO;
534	}
535
536	ret = snd_card_new(dev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1,
537			      THIS_MODULE, sizeof(struct snd_dw_hdmi), &card);
538	if (ret < 0)
539		return ret;
540
541	strlcpy(card->driver, DRIVER_NAME, sizeof(card->driver));
542	strlcpy(card->shortname, "DW-HDMI", sizeof(card->shortname));
543	snprintf(card->longname, sizeof(card->longname),
544		 "%s rev 0x%02x, irq %d", card->shortname, revision,
545		 data->irq);
546
547	dw = card->private_data;
548	dw->card = card;
549	dw->data = *data;
550	dw->revision = revision;
551
552	spin_lock_init(&dw->lock);
553
554	ret = snd_pcm_new(card, "DW HDMI", 0, 1, 0, &pcm);
555	if (ret < 0)
556		goto err;
557
558	dw->pcm = pcm;
559	pcm->private_data = dw;
560	strlcpy(pcm->name, DRIVER_NAME, sizeof(pcm->name));
561	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK, &snd_dw_hdmi_ops);
562
563	/*
564	 * To support 8-channel 96kHz audio reliably, we need 512k
565	 * to satisfy alsa with our restricted period (ERR004323).
566	 */
567	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
568			dev, 128 * 1024, 1024 * 1024);
569
570	ret = snd_card_register(card);
571	if (ret < 0)
572		goto err;
573
574	platform_set_drvdata(pdev, dw);
575
576	return 0;
577
578err:
579	snd_card_free(card);
580	return ret;
581}
582
583static int snd_dw_hdmi_remove(struct platform_device *pdev)
584{
585	struct snd_dw_hdmi *dw = platform_get_drvdata(pdev);
586
587	snd_card_free(dw->card);
588
589	return 0;
590}
591
592#if defined(CONFIG_PM_SLEEP) && defined(IS_NOT_BROKEN)
593/*
594 * This code is fine, but requires implementation in the dw_hdmi_trigger()
595 * method which is currently missing as I have no way to test this.
596 */
597static int snd_dw_hdmi_suspend(struct device *dev)
598{
599	struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
600
601	snd_power_change_state(dw->card, SNDRV_CTL_POWER_D3cold);
602
603	return 0;
604}
605
606static int snd_dw_hdmi_resume(struct device *dev)
607{
608	struct snd_dw_hdmi *dw = dev_get_drvdata(dev);
609
610	snd_power_change_state(dw->card, SNDRV_CTL_POWER_D0);
611
612	return 0;
613}
614
615static SIMPLE_DEV_PM_OPS(snd_dw_hdmi_pm, snd_dw_hdmi_suspend,
616			 snd_dw_hdmi_resume);
617#define PM_OPS &snd_dw_hdmi_pm
618#else
619#define PM_OPS NULL
620#endif
621
622static struct platform_driver snd_dw_hdmi_driver = {
623	.probe	= snd_dw_hdmi_probe,
624	.remove	= snd_dw_hdmi_remove,
625	.driver	= {
626		.name = DRIVER_NAME,
627		.pm = PM_OPS,
628	},
629};
630
631module_platform_driver(snd_dw_hdmi_driver);
632
633MODULE_AUTHOR("Russell King <rmk+kernel@arm.linux.org.uk>");
634MODULE_DESCRIPTION("Synopsis Designware HDMI AHB ALSA interface");
635MODULE_LICENSE("GPL v2");
636MODULE_ALIAS("platform:" DRIVER_NAME);