xref: /openbmc/linux/sound/soc/sunxi/sun4i-spdif.c (revision f3539c12)
1 /*
2  * ALSA SoC SPDIF Audio Layer
3  *
4  * Copyright 2015 Andrea Venturi <be17068@iperbole.bo.it>
5  * Copyright 2015 Marcus Cooper <codekipper@gmail.com>
6  *
7  * Based on the Allwinner SDK driver, released under the GPL.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  */
19 
20 #include <linux/clk.h>
21 #include <linux/delay.h>
22 #include <linux/device.h>
23 #include <linux/kernel.h>
24 #include <linux/init.h>
25 #include <linux/regmap.h>
26 #include <linux/of_address.h>
27 #include <linux/of_device.h>
28 #include <linux/ioport.h>
29 #include <linux/module.h>
30 #include <linux/platform_device.h>
31 #include <linux/pm_runtime.h>
32 #include <sound/dmaengine_pcm.h>
33 #include <sound/pcm_params.h>
34 #include <sound/soc.h>
35 
36 #define	SUN4I_SPDIF_CTL		(0x00)
37 	#define SUN4I_SPDIF_CTL_MCLKDIV(v)		((v) << 4) /* v even */
38 	#define SUN4I_SPDIF_CTL_MCLKOUTEN		BIT(2)
39 	#define SUN4I_SPDIF_CTL_GEN			BIT(1)
40 	#define SUN4I_SPDIF_CTL_RESET			BIT(0)
41 
42 #define SUN4I_SPDIF_TXCFG	(0x04)
43 	#define SUN4I_SPDIF_TXCFG_SINGLEMOD		BIT(31)
44 	#define SUN4I_SPDIF_TXCFG_ASS			BIT(17)
45 	#define SUN4I_SPDIF_TXCFG_NONAUDIO		BIT(16)
46 	#define SUN4I_SPDIF_TXCFG_TXRATIO(v)		((v) << 4)
47 	#define SUN4I_SPDIF_TXCFG_TXRATIO_MASK		GENMASK(8, 4)
48 	#define SUN4I_SPDIF_TXCFG_FMTRVD		GENMASK(3, 2)
49 	#define SUN4I_SPDIF_TXCFG_FMT16BIT		(0 << 2)
50 	#define SUN4I_SPDIF_TXCFG_FMT20BIT		(1 << 2)
51 	#define SUN4I_SPDIF_TXCFG_FMT24BIT		(2 << 2)
52 	#define SUN4I_SPDIF_TXCFG_CHSTMODE		BIT(1)
53 	#define SUN4I_SPDIF_TXCFG_TXEN			BIT(0)
54 
55 #define SUN4I_SPDIF_RXCFG	(0x08)
56 	#define SUN4I_SPDIF_RXCFG_LOCKFLAG		BIT(4)
57 	#define SUN4I_SPDIF_RXCFG_CHSTSRC		BIT(3)
58 	#define SUN4I_SPDIF_RXCFG_CHSTCP		BIT(1)
59 	#define SUN4I_SPDIF_RXCFG_RXEN			BIT(0)
60 
61 #define SUN4I_SPDIF_TXFIFO	(0x0C)
62 
63 #define SUN4I_SPDIF_RXFIFO	(0x10)
64 
65 #define SUN4I_SPDIF_FCTL	(0x14)
66 	#define SUN4I_SPDIF_FCTL_FIFOSRC		BIT(31)
67 	#define SUN4I_SPDIF_FCTL_FTX			BIT(17)
68 	#define SUN4I_SPDIF_FCTL_FRX			BIT(16)
69 	#define SUN4I_SPDIF_FCTL_TXTL(v)		((v) << 8)
70 	#define SUN4I_SPDIF_FCTL_TXTL_MASK		GENMASK(12, 8)
71 	#define SUN4I_SPDIF_FCTL_RXTL(v)		((v) << 3)
72 	#define SUN4I_SPDIF_FCTL_RXTL_MASK		GENMASK(7, 3)
73 	#define SUN4I_SPDIF_FCTL_TXIM			BIT(2)
74 	#define SUN4I_SPDIF_FCTL_RXOM(v)		((v) << 0)
75 	#define SUN4I_SPDIF_FCTL_RXOM_MASK		GENMASK(1, 0)
76 
77 #define SUN4I_SPDIF_FSTA	(0x18)
78 	#define SUN4I_SPDIF_FSTA_TXE			BIT(14)
79 	#define SUN4I_SPDIF_FSTA_TXECNTSHT		(8)
80 	#define SUN4I_SPDIF_FSTA_RXA			BIT(6)
81 	#define SUN4I_SPDIF_FSTA_RXACNTSHT		(0)
82 
83 #define SUN4I_SPDIF_INT		(0x1C)
84 	#define SUN4I_SPDIF_INT_RXLOCKEN		BIT(18)
85 	#define SUN4I_SPDIF_INT_RXUNLOCKEN		BIT(17)
86 	#define SUN4I_SPDIF_INT_RXPARERREN		BIT(16)
87 	#define SUN4I_SPDIF_INT_TXDRQEN			BIT(7)
88 	#define SUN4I_SPDIF_INT_TXUIEN			BIT(6)
89 	#define SUN4I_SPDIF_INT_TXOIEN			BIT(5)
90 	#define SUN4I_SPDIF_INT_TXEIEN			BIT(4)
91 	#define SUN4I_SPDIF_INT_RXDRQEN			BIT(2)
92 	#define SUN4I_SPDIF_INT_RXOIEN			BIT(1)
93 	#define SUN4I_SPDIF_INT_RXAIEN			BIT(0)
94 
95 #define SUN4I_SPDIF_ISTA	(0x20)
96 	#define SUN4I_SPDIF_ISTA_RXLOCKSTA		BIT(18)
97 	#define SUN4I_SPDIF_ISTA_RXUNLOCKSTA		BIT(17)
98 	#define SUN4I_SPDIF_ISTA_RXPARERRSTA		BIT(16)
99 	#define SUN4I_SPDIF_ISTA_TXUSTA			BIT(6)
100 	#define SUN4I_SPDIF_ISTA_TXOSTA			BIT(5)
101 	#define SUN4I_SPDIF_ISTA_TXESTA			BIT(4)
102 	#define SUN4I_SPDIF_ISTA_RXOSTA			BIT(1)
103 	#define SUN4I_SPDIF_ISTA_RXASTA			BIT(0)
104 
105 #define SUN4I_SPDIF_TXCNT	(0x24)
106 
107 #define SUN4I_SPDIF_RXCNT	(0x28)
108 
109 #define SUN4I_SPDIF_TXCHSTA0	(0x2C)
110 	#define SUN4I_SPDIF_TXCHSTA0_CLK(v)		((v) << 28)
111 	#define SUN4I_SPDIF_TXCHSTA0_SAMFREQ(v)		((v) << 24)
112 	#define SUN4I_SPDIF_TXCHSTA0_SAMFREQ_MASK	GENMASK(27, 24)
113 	#define SUN4I_SPDIF_TXCHSTA0_CHNUM(v)		((v) << 20)
114 	#define SUN4I_SPDIF_TXCHSTA0_CHNUM_MASK		GENMASK(23, 20)
115 	#define SUN4I_SPDIF_TXCHSTA0_SRCNUM(v)		((v) << 16)
116 	#define SUN4I_SPDIF_TXCHSTA0_CATACOD(v)		((v) << 8)
117 	#define SUN4I_SPDIF_TXCHSTA0_MODE(v)		((v) << 6)
118 	#define SUN4I_SPDIF_TXCHSTA0_EMPHASIS(v)	((v) << 3)
119 	#define SUN4I_SPDIF_TXCHSTA0_CP			BIT(2)
120 	#define SUN4I_SPDIF_TXCHSTA0_AUDIO		BIT(1)
121 	#define SUN4I_SPDIF_TXCHSTA0_PRO		BIT(0)
122 
123 #define SUN4I_SPDIF_TXCHSTA1	(0x30)
124 	#define SUN4I_SPDIF_TXCHSTA1_CGMSA(v)		((v) << 8)
125 	#define SUN4I_SPDIF_TXCHSTA1_ORISAMFREQ(v)	((v) << 4)
126 	#define SUN4I_SPDIF_TXCHSTA1_ORISAMFREQ_MASK	GENMASK(7, 4)
127 	#define SUN4I_SPDIF_TXCHSTA1_SAMWORDLEN(v)	((v) << 1)
128 	#define SUN4I_SPDIF_TXCHSTA1_MAXWORDLEN		BIT(0)
129 
130 #define SUN4I_SPDIF_RXCHSTA0	(0x34)
131 	#define SUN4I_SPDIF_RXCHSTA0_CLK(v)		((v) << 28)
132 	#define SUN4I_SPDIF_RXCHSTA0_SAMFREQ(v)		((v) << 24)
133 	#define SUN4I_SPDIF_RXCHSTA0_CHNUM(v)		((v) << 20)
134 	#define SUN4I_SPDIF_RXCHSTA0_SRCNUM(v)		((v) << 16)
135 	#define SUN4I_SPDIF_RXCHSTA0_CATACOD(v)		((v) << 8)
136 	#define SUN4I_SPDIF_RXCHSTA0_MODE(v)		((v) << 6)
137 	#define SUN4I_SPDIF_RXCHSTA0_EMPHASIS(v)	((v) << 3)
138 	#define SUN4I_SPDIF_RXCHSTA0_CP			BIT(2)
139 	#define SUN4I_SPDIF_RXCHSTA0_AUDIO		BIT(1)
140 	#define SUN4I_SPDIF_RXCHSTA0_PRO		BIT(0)
141 
142 #define SUN4I_SPDIF_RXCHSTA1	(0x38)
143 	#define SUN4I_SPDIF_RXCHSTA1_CGMSA(v)		((v) << 8)
144 	#define SUN4I_SPDIF_RXCHSTA1_ORISAMFREQ(v)	((v) << 4)
145 	#define SUN4I_SPDIF_RXCHSTA1_SAMWORDLEN(v)	((v) << 1)
146 	#define SUN4I_SPDIF_RXCHSTA1_MAXWORDLEN		BIT(0)
147 
148 /* Defines for Sampling Frequency */
149 #define SUN4I_SPDIF_SAMFREQ_44_1KHZ		0x0
150 #define SUN4I_SPDIF_SAMFREQ_NOT_INDICATED	0x1
151 #define SUN4I_SPDIF_SAMFREQ_48KHZ		0x2
152 #define SUN4I_SPDIF_SAMFREQ_32KHZ		0x3
153 #define SUN4I_SPDIF_SAMFREQ_22_05KHZ		0x4
154 #define SUN4I_SPDIF_SAMFREQ_24KHZ		0x6
155 #define SUN4I_SPDIF_SAMFREQ_88_2KHZ		0x8
156 #define SUN4I_SPDIF_SAMFREQ_76_8KHZ		0x9
157 #define SUN4I_SPDIF_SAMFREQ_96KHZ		0xa
158 #define SUN4I_SPDIF_SAMFREQ_176_4KHZ		0xc
159 #define SUN4I_SPDIF_SAMFREQ_192KHZ		0xe
160 
161 struct sun4i_spdif_dev {
162 	struct platform_device *pdev;
163 	struct clk *spdif_clk;
164 	struct clk *apb_clk;
165 	struct snd_soc_dai_driver cpu_dai_drv;
166 	struct regmap *regmap;
167 	struct snd_dmaengine_dai_dma_data dma_params_tx;
168 };
169 
170 static void sun4i_spdif_configure(struct sun4i_spdif_dev *host)
171 {
172 	/* soft reset SPDIF */
173 	regmap_write(host->regmap, SUN4I_SPDIF_CTL, SUN4I_SPDIF_CTL_RESET);
174 
175 	/* flush TX FIFO */
176 	regmap_update_bits(host->regmap, SUN4I_SPDIF_FCTL,
177 			   SUN4I_SPDIF_FCTL_FTX, SUN4I_SPDIF_FCTL_FTX);
178 
179 	/* clear TX counter */
180 	regmap_write(host->regmap, SUN4I_SPDIF_TXCNT, 0);
181 }
182 
183 static void sun4i_snd_txctrl_on(struct snd_pcm_substream *substream,
184 				struct sun4i_spdif_dev *host)
185 {
186 	if (substream->runtime->channels == 1)
187 		regmap_update_bits(host->regmap, SUN4I_SPDIF_TXCFG,
188 				   SUN4I_SPDIF_TXCFG_SINGLEMOD,
189 				   SUN4I_SPDIF_TXCFG_SINGLEMOD);
190 
191 	/* SPDIF TX ENABLE */
192 	regmap_update_bits(host->regmap, SUN4I_SPDIF_TXCFG,
193 			   SUN4I_SPDIF_TXCFG_TXEN, SUN4I_SPDIF_TXCFG_TXEN);
194 
195 	/* DRQ ENABLE */
196 	regmap_update_bits(host->regmap, SUN4I_SPDIF_INT,
197 			   SUN4I_SPDIF_INT_TXDRQEN, SUN4I_SPDIF_INT_TXDRQEN);
198 
199 	/* Global enable */
200 	regmap_update_bits(host->regmap, SUN4I_SPDIF_CTL,
201 			   SUN4I_SPDIF_CTL_GEN, SUN4I_SPDIF_CTL_GEN);
202 }
203 
204 static void sun4i_snd_txctrl_off(struct snd_pcm_substream *substream,
205 				 struct sun4i_spdif_dev *host)
206 {
207 	/* SPDIF TX DISABLE */
208 	regmap_update_bits(host->regmap, SUN4I_SPDIF_TXCFG,
209 			   SUN4I_SPDIF_TXCFG_TXEN, 0);
210 
211 	/* DRQ DISABLE */
212 	regmap_update_bits(host->regmap, SUN4I_SPDIF_INT,
213 			   SUN4I_SPDIF_INT_TXDRQEN, 0);
214 
215 	/* Global disable */
216 	regmap_update_bits(host->regmap, SUN4I_SPDIF_CTL,
217 			   SUN4I_SPDIF_CTL_GEN, 0);
218 }
219 
220 static int sun4i_spdif_startup(struct snd_pcm_substream *substream,
221 			       struct snd_soc_dai *cpu_dai)
222 {
223 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
224 	struct sun4i_spdif_dev *host = snd_soc_dai_get_drvdata(rtd->cpu_dai);
225 
226 	if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
227 		return -EINVAL;
228 
229 	sun4i_spdif_configure(host);
230 
231 	return 0;
232 }
233 
234 static int sun4i_spdif_hw_params(struct snd_pcm_substream *substream,
235 				 struct snd_pcm_hw_params *params,
236 				 struct snd_soc_dai *cpu_dai)
237 {
238 	int ret = 0;
239 	int fmt;
240 	unsigned long rate = params_rate(params);
241 	u32 mclk_div = 0;
242 	unsigned int mclk = 0;
243 	u32 reg_val;
244 	struct sun4i_spdif_dev *host = snd_soc_dai_get_drvdata(cpu_dai);
245 	struct platform_device *pdev = host->pdev;
246 
247 	/* Add the PCM and raw data select interface */
248 	switch (params_channels(params)) {
249 	case 1: /* PCM mode */
250 	case 2:
251 		fmt = 0;
252 		break;
253 	case 4: /* raw data mode */
254 		fmt = SUN4I_SPDIF_TXCFG_NONAUDIO;
255 		break;
256 	default:
257 		return -EINVAL;
258 	}
259 
260 	switch (params_format(params)) {
261 	case SNDRV_PCM_FORMAT_S16_LE:
262 		fmt |= SUN4I_SPDIF_TXCFG_FMT16BIT;
263 		break;
264 	case SNDRV_PCM_FORMAT_S20_3LE:
265 		fmt |= SUN4I_SPDIF_TXCFG_FMT20BIT;
266 		break;
267 	case SNDRV_PCM_FORMAT_S24_LE:
268 		fmt |= SUN4I_SPDIF_TXCFG_FMT24BIT;
269 		break;
270 	default:
271 		return -EINVAL;
272 	}
273 
274 	switch (rate) {
275 	case 22050:
276 	case 44100:
277 	case 88200:
278 	case 176400:
279 		mclk = 22579200;
280 		break;
281 	case 24000:
282 	case 32000:
283 	case 48000:
284 	case 96000:
285 	case 192000:
286 		mclk = 24576000;
287 		break;
288 	default:
289 		return -EINVAL;
290 	}
291 
292 	ret = clk_set_rate(host->spdif_clk, mclk);
293 	if (ret < 0) {
294 		dev_err(&pdev->dev,
295 			"Setting SPDIF clock rate for %d Hz failed!\n", mclk);
296 		return ret;
297 	}
298 
299 	regmap_update_bits(host->regmap, SUN4I_SPDIF_FCTL,
300 			   SUN4I_SPDIF_FCTL_TXIM, SUN4I_SPDIF_FCTL_TXIM);
301 
302 	switch (rate) {
303 	case 22050:
304 	case 24000:
305 		mclk_div = 8;
306 		break;
307 	case 32000:
308 		mclk_div = 6;
309 		break;
310 	case 44100:
311 	case 48000:
312 		mclk_div = 4;
313 		break;
314 	case 88200:
315 	case 96000:
316 		mclk_div = 2;
317 		break;
318 	case 176400:
319 	case 192000:
320 		mclk_div = 1;
321 		break;
322 	default:
323 		return -EINVAL;
324 	}
325 
326 	reg_val = 0;
327 	reg_val |= SUN4I_SPDIF_TXCFG_ASS;
328 	reg_val |= fmt; /* set non audio and bit depth */
329 	reg_val |= SUN4I_SPDIF_TXCFG_CHSTMODE;
330 	reg_val |= SUN4I_SPDIF_TXCFG_TXRATIO(mclk_div - 1);
331 	regmap_write(host->regmap, SUN4I_SPDIF_TXCFG, reg_val);
332 
333 	return 0;
334 }
335 
336 static int sun4i_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
337 			       struct snd_soc_dai *dai)
338 {
339 	int ret = 0;
340 	struct sun4i_spdif_dev *host = snd_soc_dai_get_drvdata(dai);
341 
342 	if (substream->stream != SNDRV_PCM_STREAM_PLAYBACK)
343 		return -EINVAL;
344 
345 	switch (cmd) {
346 	case SNDRV_PCM_TRIGGER_START:
347 	case SNDRV_PCM_TRIGGER_RESUME:
348 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
349 		sun4i_snd_txctrl_on(substream, host);
350 		break;
351 
352 	case SNDRV_PCM_TRIGGER_STOP:
353 	case SNDRV_PCM_TRIGGER_SUSPEND:
354 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
355 		sun4i_snd_txctrl_off(substream, host);
356 		break;
357 
358 	default:
359 		ret = -EINVAL;
360 		break;
361 	}
362 	return ret;
363 }
364 
365 static int sun4i_spdif_soc_dai_probe(struct snd_soc_dai *dai)
366 {
367 	struct sun4i_spdif_dev *host = snd_soc_dai_get_drvdata(dai);
368 
369 	snd_soc_dai_init_dma_data(dai, &host->dma_params_tx, NULL);
370 	return 0;
371 }
372 
373 static const struct snd_soc_dai_ops sun4i_spdif_dai_ops = {
374 	.startup	= sun4i_spdif_startup,
375 	.trigger	= sun4i_spdif_trigger,
376 	.hw_params	= sun4i_spdif_hw_params,
377 };
378 
379 static const struct regmap_config sun4i_spdif_regmap_config = {
380 	.reg_bits = 32,
381 	.reg_stride = 4,
382 	.val_bits = 32,
383 	.max_register = SUN4I_SPDIF_RXCHSTA1,
384 };
385 
386 #define SUN4I_RATES	SNDRV_PCM_RATE_8000_192000
387 
388 #define SUN4I_FORMATS	(SNDRV_PCM_FORMAT_S16_LE | \
389 				SNDRV_PCM_FORMAT_S20_3LE | \
390 				SNDRV_PCM_FORMAT_S24_LE)
391 
392 static struct snd_soc_dai_driver sun4i_spdif_dai = {
393 	.playback = {
394 		.channels_min = 1,
395 		.channels_max = 2,
396 		.rates = SUN4I_RATES,
397 		.formats = SUN4I_FORMATS,
398 	},
399 	.probe = sun4i_spdif_soc_dai_probe,
400 	.ops = &sun4i_spdif_dai_ops,
401 	.name = "spdif",
402 };
403 
404 static const struct snd_soc_dapm_widget dit_widgets[] = {
405 	SND_SOC_DAPM_OUTPUT("spdif-out"),
406 };
407 
408 static const struct snd_soc_dapm_route dit_routes[] = {
409 	{ "spdif-out", NULL, "Playback" },
410 };
411 
412 static const struct of_device_id sun4i_spdif_of_match[] = {
413 	{ .compatible = "allwinner,sun4i-a10-spdif", },
414 	{ /* sentinel */ }
415 };
416 MODULE_DEVICE_TABLE(of, sun4i_spdif_of_match);
417 
418 static const struct snd_soc_component_driver sun4i_spdif_component = {
419 	.name		= "sun4i-spdif",
420 };
421 
422 static int sun4i_spdif_runtime_suspend(struct device *dev)
423 {
424 	struct sun4i_spdif_dev *host  = dev_get_drvdata(dev);
425 
426 	clk_disable_unprepare(host->spdif_clk);
427 	clk_disable_unprepare(host->apb_clk);
428 
429 	return 0;
430 }
431 
432 static int sun4i_spdif_runtime_resume(struct device *dev)
433 {
434 	struct sun4i_spdif_dev *host  = dev_get_drvdata(dev);
435 
436 	clk_prepare_enable(host->spdif_clk);
437 	clk_prepare_enable(host->apb_clk);
438 
439 	return 0;
440 }
441 
442 static int sun4i_spdif_probe(struct platform_device *pdev)
443 {
444 	struct sun4i_spdif_dev *host;
445 	struct resource *res;
446 	int ret;
447 	void __iomem *base;
448 
449 	dev_dbg(&pdev->dev, "Entered %s\n", __func__);
450 
451 	host = devm_kzalloc(&pdev->dev, sizeof(*host), GFP_KERNEL);
452 	if (!host)
453 		return -ENOMEM;
454 
455 	host->pdev = pdev;
456 
457 	/* Initialize this copy of the CPU DAI driver structure */
458 	memcpy(&host->cpu_dai_drv, &sun4i_spdif_dai, sizeof(sun4i_spdif_dai));
459 	host->cpu_dai_drv.name = dev_name(&pdev->dev);
460 
461 	/* Get the addresses */
462 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
463 	base = devm_ioremap_resource(&pdev->dev, res);
464 	if (IS_ERR(base))
465 		return PTR_ERR(base);
466 
467 	host->regmap = devm_regmap_init_mmio(&pdev->dev, base,
468 						&sun4i_spdif_regmap_config);
469 
470 	/* Clocks */
471 	host->apb_clk = devm_clk_get(&pdev->dev, "apb");
472 	if (IS_ERR(host->apb_clk)) {
473 		dev_err(&pdev->dev, "failed to get a apb clock.\n");
474 		return PTR_ERR(host->apb_clk);
475 	}
476 
477 	host->spdif_clk = devm_clk_get(&pdev->dev, "spdif");
478 	if (IS_ERR(host->spdif_clk)) {
479 		dev_err(&pdev->dev, "failed to get a spdif clock.\n");
480 		ret = PTR_ERR(host->spdif_clk);
481 		goto err_disable_apb_clk;
482 	}
483 
484 	host->dma_params_tx.addr = res->start + SUN4I_SPDIF_TXFIFO;
485 	host->dma_params_tx.maxburst = 4;
486 	host->dma_params_tx.addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
487 
488 	platform_set_drvdata(pdev, host);
489 
490 	ret = devm_snd_soc_register_component(&pdev->dev,
491 				&sun4i_spdif_component, &sun4i_spdif_dai, 1);
492 	if (ret)
493 		goto err_disable_apb_clk;
494 
495 	pm_runtime_enable(&pdev->dev);
496 	if (!pm_runtime_enabled(&pdev->dev)) {
497 		ret = sun4i_spdif_runtime_resume(&pdev->dev);
498 		if (ret)
499 			goto err_unregister;
500 	}
501 
502 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
503 	if (ret)
504 		goto err_suspend;
505 	return 0;
506 err_suspend:
507 	if (!pm_runtime_status_suspended(&pdev->dev))
508 		sun4i_spdif_runtime_suspend(&pdev->dev);
509 err_unregister:
510 	pm_runtime_disable(&pdev->dev);
511 	snd_soc_unregister_component(&pdev->dev);
512 err_disable_apb_clk:
513 	clk_disable_unprepare(host->apb_clk);
514 	return ret;
515 }
516 
517 static int sun4i_spdif_remove(struct platform_device *pdev)
518 {
519 	pm_runtime_disable(&pdev->dev);
520 	if (!pm_runtime_status_suspended(&pdev->dev))
521 		sun4i_spdif_runtime_suspend(&pdev->dev);
522 
523 	snd_soc_unregister_platform(&pdev->dev);
524 	snd_soc_unregister_component(&pdev->dev);
525 
526 	return 0;
527 }
528 
529 static const struct dev_pm_ops sun4i_spdif_pm = {
530 	SET_RUNTIME_PM_OPS(sun4i_spdif_runtime_suspend,
531 			   sun4i_spdif_runtime_resume, NULL)
532 };
533 
534 static struct platform_driver sun4i_spdif_driver = {
535 	.driver		= {
536 		.name	= "sun4i-spdif",
537 		.of_match_table = of_match_ptr(sun4i_spdif_of_match),
538 		.pm	= &sun4i_spdif_pm,
539 	},
540 	.probe		= sun4i_spdif_probe,
541 	.remove		= sun4i_spdif_remove,
542 };
543 
544 module_platform_driver(sun4i_spdif_driver);
545 
546 MODULE_AUTHOR("Marcus Cooper <codekipper@gmail.com>");
547 MODULE_AUTHOR("Andrea Venturi <be17068@iperbole.bo.it>");
548 MODULE_DESCRIPTION("Allwinner sun4i SPDIF SoC Interface");
549 MODULE_LICENSE("GPL");
550 MODULE_ALIAS("platform:sun4i-spdif");
551