xref: /openbmc/linux/sound/soc/samsung/spdif.c (revision d6fc9fcb)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // ALSA SoC Audio Layer - Samsung S/PDIF Controller driver
4 //
5 // Copyright (c) 2010 Samsung Electronics Co. Ltd
6 //		http://www.samsung.com/
7 
8 #include <linux/clk.h>
9 #include <linux/io.h>
10 #include <linux/module.h>
11 
12 #include <sound/soc.h>
13 #include <sound/pcm_params.h>
14 
15 #include <linux/platform_data/asoc-s3c.h>
16 
17 #include "dma.h"
18 #include "spdif.h"
19 
20 /* Registers */
21 #define CLKCON				0x00
22 #define CON				0x04
23 #define BSTAS				0x08
24 #define CSTAS				0x0C
25 #define DATA_OUTBUF			0x10
26 #define DCNT				0x14
27 #define BSTAS_S				0x18
28 #define DCNT_S				0x1C
29 
30 #define CLKCTL_MASK			0x7
31 #define CLKCTL_MCLK_EXT			(0x1 << 2)
32 #define CLKCTL_PWR_ON			(0x1 << 0)
33 
34 #define CON_MASK			0x3ffffff
35 #define CON_FIFO_TH_SHIFT		19
36 #define CON_FIFO_TH_MASK		(0x7 << 19)
37 #define CON_USERDATA_23RDBIT		(0x1 << 12)
38 
39 #define CON_SW_RESET			(0x1 << 5)
40 
41 #define CON_MCLKDIV_MASK		(0x3 << 3)
42 #define CON_MCLKDIV_256FS		(0x0 << 3)
43 #define CON_MCLKDIV_384FS		(0x1 << 3)
44 #define CON_MCLKDIV_512FS		(0x2 << 3)
45 
46 #define CON_PCM_MASK			(0x3 << 1)
47 #define CON_PCM_16BIT			(0x0 << 1)
48 #define CON_PCM_20BIT			(0x1 << 1)
49 #define CON_PCM_24BIT			(0x2 << 1)
50 
51 #define CON_PCM_DATA			(0x1 << 0)
52 
53 #define CSTAS_MASK			0x3fffffff
54 #define CSTAS_SAMP_FREQ_MASK		(0xF << 24)
55 #define CSTAS_SAMP_FREQ_44		(0x0 << 24)
56 #define CSTAS_SAMP_FREQ_48		(0x2 << 24)
57 #define CSTAS_SAMP_FREQ_32		(0x3 << 24)
58 #define CSTAS_SAMP_FREQ_96		(0xA << 24)
59 
60 #define CSTAS_CATEGORY_MASK		(0xFF << 8)
61 #define CSTAS_CATEGORY_CODE_CDP		(0x01 << 8)
62 
63 #define CSTAS_NO_COPYRIGHT		(0x1 << 2)
64 
65 /**
66  * struct samsung_spdif_info - Samsung S/PDIF Controller information
67  * @lock: Spin lock for S/PDIF.
68  * @dev: The parent device passed to use from the probe.
69  * @regs: The pointer to the device register block.
70  * @clk_rate: Current clock rate for calcurate ratio.
71  * @pclk: The peri-clock pointer for spdif master operation.
72  * @sclk: The source clock pointer for making sync signals.
73  * @save_clkcon: Backup clkcon reg. in suspend.
74  * @save_con: Backup con reg. in suspend.
75  * @save_cstas: Backup cstas reg. in suspend.
76  * @dma_playback: DMA information for playback channel.
77  */
78 struct samsung_spdif_info {
79 	spinlock_t	lock;
80 	struct device	*dev;
81 	void __iomem	*regs;
82 	unsigned long	clk_rate;
83 	struct clk	*pclk;
84 	struct clk	*sclk;
85 	u32		saved_clkcon;
86 	u32		saved_con;
87 	u32		saved_cstas;
88 	struct snd_dmaengine_dai_dma_data *dma_playback;
89 };
90 
91 static struct snd_dmaengine_dai_dma_data spdif_stereo_out;
92 static struct samsung_spdif_info spdif_info;
93 
94 static inline struct samsung_spdif_info *to_info(struct snd_soc_dai *cpu_dai)
95 {
96 	return snd_soc_dai_get_drvdata(cpu_dai);
97 }
98 
99 static void spdif_snd_txctrl(struct samsung_spdif_info *spdif, int on)
100 {
101 	void __iomem *regs = spdif->regs;
102 	u32 clkcon;
103 
104 	dev_dbg(spdif->dev, "Entered %s\n", __func__);
105 
106 	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;
107 	if (on)
108 		writel(clkcon | CLKCTL_PWR_ON, regs + CLKCON);
109 	else
110 		writel(clkcon & ~CLKCTL_PWR_ON, regs + CLKCON);
111 }
112 
113 static int spdif_set_sysclk(struct snd_soc_dai *cpu_dai,
114 				int clk_id, unsigned int freq, int dir)
115 {
116 	struct samsung_spdif_info *spdif = to_info(cpu_dai);
117 	u32 clkcon;
118 
119 	dev_dbg(spdif->dev, "Entered %s\n", __func__);
120 
121 	clkcon = readl(spdif->regs + CLKCON);
122 
123 	if (clk_id == SND_SOC_SPDIF_INT_MCLK)
124 		clkcon &= ~CLKCTL_MCLK_EXT;
125 	else
126 		clkcon |= CLKCTL_MCLK_EXT;
127 
128 	writel(clkcon, spdif->regs + CLKCON);
129 
130 	spdif->clk_rate = freq;
131 
132 	return 0;
133 }
134 
135 static int spdif_trigger(struct snd_pcm_substream *substream, int cmd,
136 				struct snd_soc_dai *dai)
137 {
138 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
139 	struct samsung_spdif_info *spdif = to_info(rtd->cpu_dai);
140 	unsigned long flags;
141 
142 	dev_dbg(spdif->dev, "Entered %s\n", __func__);
143 
144 	switch (cmd) {
145 	case SNDRV_PCM_TRIGGER_START:
146 	case SNDRV_PCM_TRIGGER_RESUME:
147 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
148 		spin_lock_irqsave(&spdif->lock, flags);
149 		spdif_snd_txctrl(spdif, 1);
150 		spin_unlock_irqrestore(&spdif->lock, flags);
151 		break;
152 	case SNDRV_PCM_TRIGGER_STOP:
153 	case SNDRV_PCM_TRIGGER_SUSPEND:
154 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
155 		spin_lock_irqsave(&spdif->lock, flags);
156 		spdif_snd_txctrl(spdif, 0);
157 		spin_unlock_irqrestore(&spdif->lock, flags);
158 		break;
159 	default:
160 		return -EINVAL;
161 	}
162 
163 	return 0;
164 }
165 
166 static int spdif_sysclk_ratios[] = {
167 	512, 384, 256,
168 };
169 
170 static int spdif_hw_params(struct snd_pcm_substream *substream,
171 				struct snd_pcm_hw_params *params,
172 				struct snd_soc_dai *socdai)
173 {
174 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
175 	struct samsung_spdif_info *spdif = to_info(rtd->cpu_dai);
176 	void __iomem *regs = spdif->regs;
177 	struct snd_dmaengine_dai_dma_data *dma_data;
178 	u32 con, clkcon, cstas;
179 	unsigned long flags;
180 	int i, ratio;
181 
182 	dev_dbg(spdif->dev, "Entered %s\n", __func__);
183 
184 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
185 		dma_data = spdif->dma_playback;
186 	else {
187 		dev_err(spdif->dev, "Capture is not supported\n");
188 		return -EINVAL;
189 	}
190 
191 	snd_soc_dai_set_dma_data(rtd->cpu_dai, substream, dma_data);
192 
193 	spin_lock_irqsave(&spdif->lock, flags);
194 
195 	con = readl(regs + CON) & CON_MASK;
196 	cstas = readl(regs + CSTAS) & CSTAS_MASK;
197 	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;
198 
199 	con &= ~CON_FIFO_TH_MASK;
200 	con |= (0x7 << CON_FIFO_TH_SHIFT);
201 	con |= CON_USERDATA_23RDBIT;
202 	con |= CON_PCM_DATA;
203 
204 	con &= ~CON_PCM_MASK;
205 	switch (params_width(params)) {
206 	case 16:
207 		con |= CON_PCM_16BIT;
208 		break;
209 	default:
210 		dev_err(spdif->dev, "Unsupported data size.\n");
211 		goto err;
212 	}
213 
214 	ratio = spdif->clk_rate / params_rate(params);
215 	for (i = 0; i < ARRAY_SIZE(spdif_sysclk_ratios); i++)
216 		if (ratio == spdif_sysclk_ratios[i])
217 			break;
218 	if (i == ARRAY_SIZE(spdif_sysclk_ratios)) {
219 		dev_err(spdif->dev, "Invalid clock ratio %ld/%d\n",
220 				spdif->clk_rate, params_rate(params));
221 		goto err;
222 	}
223 
224 	con &= ~CON_MCLKDIV_MASK;
225 	switch (ratio) {
226 	case 256:
227 		con |= CON_MCLKDIV_256FS;
228 		break;
229 	case 384:
230 		con |= CON_MCLKDIV_384FS;
231 		break;
232 	case 512:
233 		con |= CON_MCLKDIV_512FS;
234 		break;
235 	}
236 
237 	cstas &= ~CSTAS_SAMP_FREQ_MASK;
238 	switch (params_rate(params)) {
239 	case 44100:
240 		cstas |= CSTAS_SAMP_FREQ_44;
241 		break;
242 	case 48000:
243 		cstas |= CSTAS_SAMP_FREQ_48;
244 		break;
245 	case 32000:
246 		cstas |= CSTAS_SAMP_FREQ_32;
247 		break;
248 	case 96000:
249 		cstas |= CSTAS_SAMP_FREQ_96;
250 		break;
251 	default:
252 		dev_err(spdif->dev, "Invalid sampling rate %d\n",
253 				params_rate(params));
254 		goto err;
255 	}
256 
257 	cstas &= ~CSTAS_CATEGORY_MASK;
258 	cstas |= CSTAS_CATEGORY_CODE_CDP;
259 	cstas |= CSTAS_NO_COPYRIGHT;
260 
261 	writel(con, regs + CON);
262 	writel(cstas, regs + CSTAS);
263 	writel(clkcon, regs + CLKCON);
264 
265 	spin_unlock_irqrestore(&spdif->lock, flags);
266 
267 	return 0;
268 err:
269 	spin_unlock_irqrestore(&spdif->lock, flags);
270 	return -EINVAL;
271 }
272 
273 static void spdif_shutdown(struct snd_pcm_substream *substream,
274 				struct snd_soc_dai *dai)
275 {
276 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
277 	struct samsung_spdif_info *spdif = to_info(rtd->cpu_dai);
278 	void __iomem *regs = spdif->regs;
279 	u32 con, clkcon;
280 
281 	dev_dbg(spdif->dev, "Entered %s\n", __func__);
282 
283 	con = readl(regs + CON) & CON_MASK;
284 	clkcon = readl(regs + CLKCON) & CLKCTL_MASK;
285 
286 	writel(con | CON_SW_RESET, regs + CON);
287 	cpu_relax();
288 
289 	writel(clkcon & ~CLKCTL_PWR_ON, regs + CLKCON);
290 }
291 
292 #ifdef CONFIG_PM
293 static int spdif_suspend(struct snd_soc_dai *cpu_dai)
294 {
295 	struct samsung_spdif_info *spdif = to_info(cpu_dai);
296 	u32 con = spdif->saved_con;
297 
298 	dev_dbg(spdif->dev, "Entered %s\n", __func__);
299 
300 	spdif->saved_clkcon = readl(spdif->regs	+ CLKCON) & CLKCTL_MASK;
301 	spdif->saved_con = readl(spdif->regs + CON) & CON_MASK;
302 	spdif->saved_cstas = readl(spdif->regs + CSTAS) & CSTAS_MASK;
303 
304 	writel(con | CON_SW_RESET, spdif->regs + CON);
305 	cpu_relax();
306 
307 	return 0;
308 }
309 
310 static int spdif_resume(struct snd_soc_dai *cpu_dai)
311 {
312 	struct samsung_spdif_info *spdif = to_info(cpu_dai);
313 
314 	dev_dbg(spdif->dev, "Entered %s\n", __func__);
315 
316 	writel(spdif->saved_clkcon, spdif->regs	+ CLKCON);
317 	writel(spdif->saved_con, spdif->regs + CON);
318 	writel(spdif->saved_cstas, spdif->regs + CSTAS);
319 
320 	return 0;
321 }
322 #else
323 #define spdif_suspend NULL
324 #define spdif_resume NULL
325 #endif
326 
327 static const struct snd_soc_dai_ops spdif_dai_ops = {
328 	.set_sysclk	= spdif_set_sysclk,
329 	.trigger	= spdif_trigger,
330 	.hw_params	= spdif_hw_params,
331 	.shutdown	= spdif_shutdown,
332 };
333 
334 static struct snd_soc_dai_driver samsung_spdif_dai = {
335 	.name = "samsung-spdif",
336 	.playback = {
337 		.stream_name = "S/PDIF Playback",
338 		.channels_min = 2,
339 		.channels_max = 2,
340 		.rates = (SNDRV_PCM_RATE_32000 |
341 				SNDRV_PCM_RATE_44100 |
342 				SNDRV_PCM_RATE_48000 |
343 				SNDRV_PCM_RATE_96000),
344 		.formats = SNDRV_PCM_FMTBIT_S16_LE, },
345 	.ops = &spdif_dai_ops,
346 	.suspend = spdif_suspend,
347 	.resume = spdif_resume,
348 };
349 
350 static const struct snd_soc_component_driver samsung_spdif_component = {
351 	.name		= "samsung-spdif",
352 };
353 
354 static int spdif_probe(struct platform_device *pdev)
355 {
356 	struct s3c_audio_pdata *spdif_pdata;
357 	struct resource *mem_res;
358 	struct samsung_spdif_info *spdif;
359 	dma_filter_fn filter;
360 	int ret;
361 
362 	spdif_pdata = pdev->dev.platform_data;
363 
364 	dev_dbg(&pdev->dev, "Entered %s\n", __func__);
365 
366 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
367 	if (!mem_res) {
368 		dev_err(&pdev->dev, "Unable to get register resource.\n");
369 		return -ENXIO;
370 	}
371 
372 	if (spdif_pdata && spdif_pdata->cfg_gpio
373 			&& spdif_pdata->cfg_gpio(pdev)) {
374 		dev_err(&pdev->dev, "Unable to configure GPIO pins\n");
375 		return -EINVAL;
376 	}
377 
378 	spdif = &spdif_info;
379 	spdif->dev = &pdev->dev;
380 
381 	spin_lock_init(&spdif->lock);
382 
383 	spdif->pclk = devm_clk_get(&pdev->dev, "spdif");
384 	if (IS_ERR(spdif->pclk)) {
385 		dev_err(&pdev->dev, "failed to get peri-clock\n");
386 		ret = -ENOENT;
387 		goto err0;
388 	}
389 	ret = clk_prepare_enable(spdif->pclk);
390 	if (ret)
391 		goto err0;
392 
393 	spdif->sclk = devm_clk_get(&pdev->dev, "sclk_spdif");
394 	if (IS_ERR(spdif->sclk)) {
395 		dev_err(&pdev->dev, "failed to get internal source clock\n");
396 		ret = -ENOENT;
397 		goto err1;
398 	}
399 	ret = clk_prepare_enable(spdif->sclk);
400 	if (ret)
401 		goto err1;
402 
403 	/* Request S/PDIF Register's memory region */
404 	if (!request_mem_region(mem_res->start,
405 				resource_size(mem_res), "samsung-spdif")) {
406 		dev_err(&pdev->dev, "Unable to request register region\n");
407 		ret = -EBUSY;
408 		goto err2;
409 	}
410 
411 	spdif->regs = ioremap(mem_res->start, 0x100);
412 	if (spdif->regs == NULL) {
413 		dev_err(&pdev->dev, "Cannot ioremap registers\n");
414 		ret = -ENXIO;
415 		goto err3;
416 	}
417 
418 	spdif_stereo_out.addr_width = 2;
419 	spdif_stereo_out.addr = mem_res->start + DATA_OUTBUF;
420 	filter = NULL;
421 	if (spdif_pdata) {
422 		spdif_stereo_out.filter_data = spdif_pdata->dma_playback;
423 		filter = spdif_pdata->dma_filter;
424 	}
425 	spdif->dma_playback = &spdif_stereo_out;
426 
427 	ret = samsung_asoc_dma_platform_register(&pdev->dev, filter,
428 						 NULL, NULL, NULL);
429 	if (ret) {
430 		dev_err(&pdev->dev, "failed to register DMA: %d\n", ret);
431 		goto err4;
432 	}
433 
434 	dev_set_drvdata(&pdev->dev, spdif);
435 
436 	ret = devm_snd_soc_register_component(&pdev->dev,
437 			&samsung_spdif_component, &samsung_spdif_dai, 1);
438 	if (ret != 0) {
439 		dev_err(&pdev->dev, "fail to register dai\n");
440 		goto err4;
441 	}
442 
443 	return 0;
444 err4:
445 	iounmap(spdif->regs);
446 err3:
447 	release_mem_region(mem_res->start, resource_size(mem_res));
448 err2:
449 	clk_disable_unprepare(spdif->sclk);
450 err1:
451 	clk_disable_unprepare(spdif->pclk);
452 err0:
453 	return ret;
454 }
455 
456 static int spdif_remove(struct platform_device *pdev)
457 {
458 	struct samsung_spdif_info *spdif = &spdif_info;
459 	struct resource *mem_res;
460 
461 	iounmap(spdif->regs);
462 
463 	mem_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
464 	if (mem_res)
465 		release_mem_region(mem_res->start, resource_size(mem_res));
466 
467 	clk_disable_unprepare(spdif->sclk);
468 	clk_disable_unprepare(spdif->pclk);
469 
470 	return 0;
471 }
472 
473 static struct platform_driver samsung_spdif_driver = {
474 	.probe	= spdif_probe,
475 	.remove	= spdif_remove,
476 	.driver	= {
477 		.name	= "samsung-spdif",
478 	},
479 };
480 
481 module_platform_driver(samsung_spdif_driver);
482 
483 MODULE_AUTHOR("Seungwhan Youn, <sw.youn@samsung.com>");
484 MODULE_DESCRIPTION("Samsung S/PDIF Controller Driver");
485 MODULE_LICENSE("GPL");
486 MODULE_ALIAS("platform:samsung-spdif");
487