xref: /linux/sound/soc/img/img-spdif-out.c (revision db10cb9b) 
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * IMG SPDIF output controller driver
4  *
5  * Copyright (C) 2015 Imagination Technologies Ltd.
6  *
7  * Author: Damien Horsley <Damien.Horsley@imgtec.com>
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/init.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/reset.h>
18 
19 #include <sound/core.h>
20 #include <sound/dmaengine_pcm.h>
21 #include <sound/initval.h>
22 #include <sound/pcm.h>
23 #include <sound/pcm_params.h>
24 #include <sound/soc.h>
25 
26 #define IMG_SPDIF_OUT_TX_FIFO		0x0
27 
28 #define IMG_SPDIF_OUT_CTL		0x4
29 #define IMG_SPDIF_OUT_CTL_FS_MASK	BIT(4)
30 #define IMG_SPDIF_OUT_CTL_CLK_MASK	BIT(2)
31 #define IMG_SPDIF_OUT_CTL_SRT_MASK	BIT(0)
32 
33 #define IMG_SPDIF_OUT_CSL		0x14
34 
35 #define IMG_SPDIF_OUT_CSH_UV		0x18
36 #define IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT	0
37 #define IMG_SPDIF_OUT_CSH_UV_CSH_MASK	0xff
38 
39 struct img_spdif_out {
40 	spinlock_t lock;
41 	void __iomem *base;
42 	struct clk *clk_sys;
43 	struct clk *clk_ref;
44 	struct snd_dmaengine_dai_dma_data dma_data;
45 	struct device *dev;
46 	struct reset_control *rst;
47 	u32 suspend_ctl;
48 	u32 suspend_csl;
49 	u32 suspend_csh;
50 };
51 
52 static int img_spdif_out_runtime_suspend(struct device *dev)
53 {
54 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
55 
56 	clk_disable_unprepare(spdif->clk_ref);
57 	clk_disable_unprepare(spdif->clk_sys);
58 
59 	return 0;
60 }
61 
62 static int img_spdif_out_runtime_resume(struct device *dev)
63 {
64 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
65 	int ret;
66 
67 	ret = clk_prepare_enable(spdif->clk_sys);
68 	if (ret) {
69 		dev_err(dev, "clk_enable failed: %d\n", ret);
70 		return ret;
71 	}
72 
73 	ret = clk_prepare_enable(spdif->clk_ref);
74 	if (ret) {
75 		dev_err(dev, "clk_enable failed: %d\n", ret);
76 		clk_disable_unprepare(spdif->clk_sys);
77 		return ret;
78 	}
79 
80 	return 0;
81 }
82 
83 static inline void img_spdif_out_writel(struct img_spdif_out *spdif, u32 val,
84 				u32 reg)
85 {
86 	writel(val, spdif->base + reg);
87 }
88 
89 static inline u32 img_spdif_out_readl(struct img_spdif_out *spdif, u32 reg)
90 {
91 	return readl(spdif->base + reg);
92 }
93 
94 static void img_spdif_out_reset(struct img_spdif_out *spdif)
95 {
96 	u32 ctl, status_low, status_high;
97 
98 	ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL) &
99 			~IMG_SPDIF_OUT_CTL_SRT_MASK;
100 	status_low = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
101 	status_high = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
102 
103 	reset_control_assert(spdif->rst);
104 	reset_control_deassert(spdif->rst);
105 
106 	img_spdif_out_writel(spdif, ctl, IMG_SPDIF_OUT_CTL);
107 	img_spdif_out_writel(spdif, status_low, IMG_SPDIF_OUT_CSL);
108 	img_spdif_out_writel(spdif, status_high, IMG_SPDIF_OUT_CSH_UV);
109 }
110 
111 static int img_spdif_out_info(struct snd_kcontrol *kcontrol,
112 					struct snd_ctl_elem_info *uinfo)
113 {
114 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
115 	uinfo->count = 1;
116 
117 	return 0;
118 }
119 
120 static int img_spdif_out_get_status_mask(struct snd_kcontrol *kcontrol,
121 				       struct snd_ctl_elem_value *ucontrol)
122 {
123 	ucontrol->value.iec958.status[0] = 0xff;
124 	ucontrol->value.iec958.status[1] = 0xff;
125 	ucontrol->value.iec958.status[2] = 0xff;
126 	ucontrol->value.iec958.status[3] = 0xff;
127 	ucontrol->value.iec958.status[4] = 0xff;
128 
129 	return 0;
130 }
131 
132 static int img_spdif_out_get_status(struct snd_kcontrol *kcontrol,
133 				  struct snd_ctl_elem_value *ucontrol)
134 {
135 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
136 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
137 	u32 reg;
138 	unsigned long flags;
139 
140 	spin_lock_irqsave(&spdif->lock, flags);
141 
142 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
143 	ucontrol->value.iec958.status[0] = reg & 0xff;
144 	ucontrol->value.iec958.status[1] = (reg >> 8) & 0xff;
145 	ucontrol->value.iec958.status[2] = (reg >> 16) & 0xff;
146 	ucontrol->value.iec958.status[3] = (reg >> 24) & 0xff;
147 
148 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
149 	ucontrol->value.iec958.status[4] =
150 		(reg & IMG_SPDIF_OUT_CSH_UV_CSH_MASK) >>
151 		IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
152 
153 	spin_unlock_irqrestore(&spdif->lock, flags);
154 
155 	return 0;
156 }
157 
158 static int img_spdif_out_set_status(struct snd_kcontrol *kcontrol,
159 				  struct snd_ctl_elem_value *ucontrol)
160 {
161 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
162 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
163 	u32 reg;
164 	unsigned long flags;
165 
166 	reg = ((u32)ucontrol->value.iec958.status[3] << 24);
167 	reg |= ((u32)ucontrol->value.iec958.status[2] << 16);
168 	reg |= ((u32)ucontrol->value.iec958.status[1] << 8);
169 	reg |= (u32)ucontrol->value.iec958.status[0];
170 
171 	spin_lock_irqsave(&spdif->lock, flags);
172 
173 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSL);
174 
175 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
176 	reg &= ~IMG_SPDIF_OUT_CSH_UV_CSH_MASK;
177 	reg |= (u32)ucontrol->value.iec958.status[4] <<
178 			IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
179 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSH_UV);
180 
181 	spin_unlock_irqrestore(&spdif->lock, flags);
182 
183 	return 0;
184 }
185 
186 static struct snd_kcontrol_new img_spdif_out_controls[] = {
187 	{
188 		.access = SNDRV_CTL_ELEM_ACCESS_READ,
189 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
190 		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
191 		.info = img_spdif_out_info,
192 		.get = img_spdif_out_get_status_mask
193 	},
194 	{
195 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
196 		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
197 		.info = img_spdif_out_info,
198 		.get = img_spdif_out_get_status,
199 		.put = img_spdif_out_set_status
200 	}
201 };
202 
203 static int img_spdif_out_trigger(struct snd_pcm_substream *substream, int cmd,
204 			struct snd_soc_dai *dai)
205 {
206 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
207 	u32 reg;
208 	unsigned long flags;
209 
210 	switch (cmd) {
211 	case SNDRV_PCM_TRIGGER_START:
212 	case SNDRV_PCM_TRIGGER_RESUME:
213 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
214 		reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
215 		reg |= IMG_SPDIF_OUT_CTL_SRT_MASK;
216 		img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
217 		break;
218 	case SNDRV_PCM_TRIGGER_STOP:
219 	case SNDRV_PCM_TRIGGER_SUSPEND:
220 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
221 		spin_lock_irqsave(&spdif->lock, flags);
222 		img_spdif_out_reset(spdif);
223 		spin_unlock_irqrestore(&spdif->lock, flags);
224 		break;
225 	default:
226 		return -EINVAL;
227 	}
228 
229 	return 0;
230 }
231 
232 static int img_spdif_out_hw_params(struct snd_pcm_substream *substream,
233 	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
234 {
235 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
236 	unsigned int channels;
237 	long pre_div_a, pre_div_b, diff_a, diff_b, rate, clk_rate;
238 	u32 reg;
239 	snd_pcm_format_t format;
240 
241 	rate = params_rate(params);
242 	format = params_format(params);
243 	channels = params_channels(params);
244 
245 	dev_dbg(spdif->dev, "hw_params rate %ld channels %u format %u\n",
246 			rate, channels, format);
247 
248 	if (format != SNDRV_PCM_FORMAT_S32_LE)
249 		return -EINVAL;
250 
251 	if (channels != 2)
252 		return -EINVAL;
253 
254 	pre_div_a = clk_round_rate(spdif->clk_ref, rate * 256);
255 	if (pre_div_a < 0)
256 		return pre_div_a;
257 	pre_div_b = clk_round_rate(spdif->clk_ref, rate * 384);
258 	if (pre_div_b < 0)
259 		return pre_div_b;
260 
261 	diff_a = abs((pre_div_a / 256) - rate);
262 	diff_b = abs((pre_div_b / 384) - rate);
263 
264 	/* If diffs are equal, use lower clock rate */
265 	if (diff_a > diff_b)
266 		clk_set_rate(spdif->clk_ref, pre_div_b);
267 	else
268 		clk_set_rate(spdif->clk_ref, pre_div_a);
269 
270 	/*
271 	 * Another driver (eg machine driver) may have rejected the above
272 	 * change. Get the current rate and set the register bit according to
273 	 * the new min diff
274 	 */
275 	clk_rate = clk_get_rate(spdif->clk_ref);
276 
277 	diff_a = abs((clk_rate / 256) - rate);
278 	diff_b = abs((clk_rate / 384) - rate);
279 
280 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
281 	if (diff_a <= diff_b)
282 		reg &= ~IMG_SPDIF_OUT_CTL_CLK_MASK;
283 	else
284 		reg |= IMG_SPDIF_OUT_CTL_CLK_MASK;
285 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
286 
287 	return 0;
288 }
289 
290 static int img_spdif_out_dai_probe(struct snd_soc_dai *dai)
291 {
292 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
293 
294 	snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);
295 
296 	snd_soc_add_dai_controls(dai, img_spdif_out_controls,
297 			ARRAY_SIZE(img_spdif_out_controls));
298 
299 	return 0;
300 }
301 
302 static const struct snd_soc_dai_ops img_spdif_out_dai_ops = {
303 	.probe		= img_spdif_out_dai_probe,
304 	.trigger	= img_spdif_out_trigger,
305 	.hw_params	= img_spdif_out_hw_params
306 };
307 
308 static struct snd_soc_dai_driver img_spdif_out_dai = {
309 	.playback = {
310 		.channels_min = 2,
311 		.channels_max = 2,
312 		.rates = SNDRV_PCM_RATE_8000_192000,
313 		.formats = SNDRV_PCM_FMTBIT_S32_LE
314 	},
315 	.ops = &img_spdif_out_dai_ops
316 };
317 
318 static const struct snd_soc_component_driver img_spdif_out_component = {
319 	.name = "img-spdif-out",
320 	.legacy_dai_naming = 1,
321 };
322 
323 static int img_spdif_out_probe(struct platform_device *pdev)
324 {
325 	struct img_spdif_out *spdif;
326 	struct resource *res;
327 	void __iomem *base;
328 	int ret;
329 	struct device *dev = &pdev->dev;
330 
331 	spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);
332 	if (!spdif)
333 		return -ENOMEM;
334 
335 	platform_set_drvdata(pdev, spdif);
336 
337 	spdif->dev = &pdev->dev;
338 
339 	base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
340 	if (IS_ERR(base))
341 		return PTR_ERR(base);
342 
343 	spdif->base = base;
344 
345 	spdif->rst = devm_reset_control_get_exclusive(&pdev->dev, "rst");
346 	if (IS_ERR(spdif->rst))
347 		return dev_err_probe(&pdev->dev, PTR_ERR(spdif->rst),
348 				     "No top level reset found\n");
349 
350 	spdif->clk_sys = devm_clk_get(&pdev->dev, "sys");
351 	if (IS_ERR(spdif->clk_sys))
352 		return dev_err_probe(dev, PTR_ERR(spdif->clk_sys),
353 				     "Failed to acquire clock 'sys'\n");
354 
355 	spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");
356 	if (IS_ERR(spdif->clk_ref))
357 		return dev_err_probe(dev, PTR_ERR(spdif->clk_ref),
358 				     "Failed to acquire clock 'ref'\n");
359 
360 	pm_runtime_enable(&pdev->dev);
361 	if (!pm_runtime_enabled(&pdev->dev)) {
362 		ret = img_spdif_out_runtime_resume(&pdev->dev);
363 		if (ret)
364 			goto err_pm_disable;
365 	}
366 	ret = pm_runtime_resume_and_get(&pdev->dev);
367 	if (ret < 0)
368 		goto err_suspend;
369 
370 	img_spdif_out_writel(spdif, IMG_SPDIF_OUT_CTL_FS_MASK,
371 			     IMG_SPDIF_OUT_CTL);
372 
373 	img_spdif_out_reset(spdif);
374 	pm_runtime_put(&pdev->dev);
375 
376 	spin_lock_init(&spdif->lock);
377 
378 	spdif->dma_data.addr = res->start + IMG_SPDIF_OUT_TX_FIFO;
379 	spdif->dma_data.addr_width = 4;
380 	spdif->dma_data.maxburst = 4;
381 
382 	ret = devm_snd_soc_register_component(&pdev->dev,
383 			&img_spdif_out_component,
384 			&img_spdif_out_dai, 1);
385 	if (ret)
386 		goto err_suspend;
387 
388 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
389 	if (ret)
390 		goto err_suspend;
391 
392 	dev_dbg(&pdev->dev, "Probe successful\n");
393 
394 	return 0;
395 
396 err_suspend:
397 	if (!pm_runtime_status_suspended(&pdev->dev))
398 		img_spdif_out_runtime_suspend(&pdev->dev);
399 err_pm_disable:
400 	pm_runtime_disable(&pdev->dev);
401 
402 	return ret;
403 }
404 
405 static void img_spdif_out_dev_remove(struct platform_device *pdev)
406 {
407 	pm_runtime_disable(&pdev->dev);
408 	if (!pm_runtime_status_suspended(&pdev->dev))
409 		img_spdif_out_runtime_suspend(&pdev->dev);
410 }
411 
412 #ifdef CONFIG_PM_SLEEP
413 static int img_spdif_out_suspend(struct device *dev)
414 {
415 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
416 	int ret;
417 
418 	if (pm_runtime_status_suspended(dev)) {
419 		ret = img_spdif_out_runtime_resume(dev);
420 		if (ret)
421 			return ret;
422 	}
423 
424 	spdif->suspend_ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
425 	spdif->suspend_csl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
426 	spdif->suspend_csh = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
427 
428 	img_spdif_out_runtime_suspend(dev);
429 
430 	return 0;
431 }
432 
433 static int img_spdif_out_resume(struct device *dev)
434 {
435 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
436 	int ret;
437 
438 	ret = img_spdif_out_runtime_resume(dev);
439 	if (ret)
440 		return ret;
441 
442 	img_spdif_out_writel(spdif, spdif->suspend_ctl, IMG_SPDIF_OUT_CTL);
443 	img_spdif_out_writel(spdif, spdif->suspend_csl, IMG_SPDIF_OUT_CSL);
444 	img_spdif_out_writel(spdif, spdif->suspend_csh, IMG_SPDIF_OUT_CSH_UV);
445 
446 	if (pm_runtime_status_suspended(dev))
447 		img_spdif_out_runtime_suspend(dev);
448 
449 	return 0;
450 }
451 #endif
452 static const struct of_device_id img_spdif_out_of_match[] = {
453 	{ .compatible = "img,spdif-out" },
454 	{}
455 };
456 MODULE_DEVICE_TABLE(of, img_spdif_out_of_match);
457 
458 static const struct dev_pm_ops img_spdif_out_pm_ops = {
459 	SET_RUNTIME_PM_OPS(img_spdif_out_runtime_suspend,
460 			   img_spdif_out_runtime_resume, NULL)
461 	SET_SYSTEM_SLEEP_PM_OPS(img_spdif_out_suspend, img_spdif_out_resume)
462 };
463 
464 static struct platform_driver img_spdif_out_driver = {
465 	.driver = {
466 		.name = "img-spdif-out",
467 		.of_match_table = img_spdif_out_of_match,
468 		.pm = &img_spdif_out_pm_ops
469 	},
470 	.probe = img_spdif_out_probe,
471 	.remove_new = img_spdif_out_dev_remove
472 };
473 module_platform_driver(img_spdif_out_driver);
474 
475 MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
476 MODULE_DESCRIPTION("IMG SPDIF Output driver");
477 MODULE_LICENSE("GPL v2");
478