xref: /openbmc/linux/sound/soc/img/img-spdif-out.c (revision e3b9f1e8)
1 /*
2  * IMG SPDIF output controller driver
3  *
4  * Copyright (C) 2015 Imagination Technologies Ltd.
5  *
6  * Author: Damien Horsley <Damien.Horsley@imgtec.com>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms and conditions of the GNU General Public License,
10  * version 2, as published by the Free Software Foundation.
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/init.h>
15 #include <linux/kernel.h>
16 #include <linux/module.h>
17 #include <linux/of.h>
18 #include <linux/platform_device.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/reset.h>
21 
22 #include <sound/core.h>
23 #include <sound/dmaengine_pcm.h>
24 #include <sound/initval.h>
25 #include <sound/pcm.h>
26 #include <sound/pcm_params.h>
27 #include <sound/soc.h>
28 
29 #define IMG_SPDIF_OUT_TX_FIFO		0x0
30 
31 #define IMG_SPDIF_OUT_CTL		0x4
32 #define IMG_SPDIF_OUT_CTL_FS_MASK	BIT(4)
33 #define IMG_SPDIF_OUT_CTL_CLK_MASK	BIT(2)
34 #define IMG_SPDIF_OUT_CTL_SRT_MASK	BIT(0)
35 
36 #define IMG_SPDIF_OUT_CSL		0x14
37 
38 #define IMG_SPDIF_OUT_CSH_UV		0x18
39 #define IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT	0
40 #define IMG_SPDIF_OUT_CSH_UV_CSH_MASK	0xff
41 
42 struct img_spdif_out {
43 	spinlock_t lock;
44 	void __iomem *base;
45 	struct clk *clk_sys;
46 	struct clk *clk_ref;
47 	struct snd_dmaengine_dai_dma_data dma_data;
48 	struct device *dev;
49 	struct reset_control *rst;
50 	u32 suspend_ctl;
51 	u32 suspend_csl;
52 	u32 suspend_csh;
53 };
54 
55 static int img_spdif_out_runtime_suspend(struct device *dev)
56 {
57 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
58 
59 	clk_disable_unprepare(spdif->clk_ref);
60 	clk_disable_unprepare(spdif->clk_sys);
61 
62 	return 0;
63 }
64 
65 static int img_spdif_out_runtime_resume(struct device *dev)
66 {
67 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
68 	int ret;
69 
70 	ret = clk_prepare_enable(spdif->clk_sys);
71 	if (ret) {
72 		dev_err(dev, "clk_enable failed: %d\n", ret);
73 		return ret;
74 	}
75 
76 	ret = clk_prepare_enable(spdif->clk_ref);
77 	if (ret) {
78 		dev_err(dev, "clk_enable failed: %d\n", ret);
79 		clk_disable_unprepare(spdif->clk_sys);
80 		return ret;
81 	}
82 
83 	return 0;
84 }
85 
86 static inline void img_spdif_out_writel(struct img_spdif_out *spdif, u32 val,
87 				u32 reg)
88 {
89 	writel(val, spdif->base + reg);
90 }
91 
92 static inline u32 img_spdif_out_readl(struct img_spdif_out *spdif, u32 reg)
93 {
94 	return readl(spdif->base + reg);
95 }
96 
97 static void img_spdif_out_reset(struct img_spdif_out *spdif)
98 {
99 	u32 ctl, status_low, status_high;
100 
101 	ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL) &
102 			~IMG_SPDIF_OUT_CTL_SRT_MASK;
103 	status_low = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
104 	status_high = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
105 
106 	reset_control_assert(spdif->rst);
107 	reset_control_deassert(spdif->rst);
108 
109 	img_spdif_out_writel(spdif, ctl, IMG_SPDIF_OUT_CTL);
110 	img_spdif_out_writel(spdif, status_low, IMG_SPDIF_OUT_CSL);
111 	img_spdif_out_writel(spdif, status_high, IMG_SPDIF_OUT_CSH_UV);
112 }
113 
114 static int img_spdif_out_info(struct snd_kcontrol *kcontrol,
115 					struct snd_ctl_elem_info *uinfo)
116 {
117 	uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958;
118 	uinfo->count = 1;
119 
120 	return 0;
121 }
122 
123 static int img_spdif_out_get_status_mask(struct snd_kcontrol *kcontrol,
124 				       struct snd_ctl_elem_value *ucontrol)
125 {
126 	ucontrol->value.iec958.status[0] = 0xff;
127 	ucontrol->value.iec958.status[1] = 0xff;
128 	ucontrol->value.iec958.status[2] = 0xff;
129 	ucontrol->value.iec958.status[3] = 0xff;
130 	ucontrol->value.iec958.status[4] = 0xff;
131 
132 	return 0;
133 }
134 
135 static int img_spdif_out_get_status(struct snd_kcontrol *kcontrol,
136 				  struct snd_ctl_elem_value *ucontrol)
137 {
138 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
139 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
140 	u32 reg;
141 	unsigned long flags;
142 
143 	spin_lock_irqsave(&spdif->lock, flags);
144 
145 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
146 	ucontrol->value.iec958.status[0] = reg & 0xff;
147 	ucontrol->value.iec958.status[1] = (reg >> 8) & 0xff;
148 	ucontrol->value.iec958.status[2] = (reg >> 16) & 0xff;
149 	ucontrol->value.iec958.status[3] = (reg >> 24) & 0xff;
150 
151 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
152 	ucontrol->value.iec958.status[4] =
153 		(reg & IMG_SPDIF_OUT_CSH_UV_CSH_MASK) >>
154 		IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
155 
156 	spin_unlock_irqrestore(&spdif->lock, flags);
157 
158 	return 0;
159 }
160 
161 static int img_spdif_out_set_status(struct snd_kcontrol *kcontrol,
162 				  struct snd_ctl_elem_value *ucontrol)
163 {
164 	struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol);
165 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(cpu_dai);
166 	u32 reg;
167 	unsigned long flags;
168 
169 	reg = ((u32)ucontrol->value.iec958.status[3] << 24);
170 	reg |= ((u32)ucontrol->value.iec958.status[2] << 16);
171 	reg |= ((u32)ucontrol->value.iec958.status[1] << 8);
172 	reg |= (u32)ucontrol->value.iec958.status[0];
173 
174 	spin_lock_irqsave(&spdif->lock, flags);
175 
176 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSL);
177 
178 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
179 	reg &= ~IMG_SPDIF_OUT_CSH_UV_CSH_MASK;
180 	reg |= (u32)ucontrol->value.iec958.status[4] <<
181 			IMG_SPDIF_OUT_CSH_UV_CSH_SHIFT;
182 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CSH_UV);
183 
184 	spin_unlock_irqrestore(&spdif->lock, flags);
185 
186 	return 0;
187 }
188 
189 static struct snd_kcontrol_new img_spdif_out_controls[] = {
190 	{
191 		.access = SNDRV_CTL_ELEM_ACCESS_READ,
192 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
193 		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, MASK),
194 		.info = img_spdif_out_info,
195 		.get = img_spdif_out_get_status_mask
196 	},
197 	{
198 		.iface = SNDRV_CTL_ELEM_IFACE_PCM,
199 		.name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT),
200 		.info = img_spdif_out_info,
201 		.get = img_spdif_out_get_status,
202 		.put = img_spdif_out_set_status
203 	}
204 };
205 
206 static int img_spdif_out_trigger(struct snd_pcm_substream *substream, int cmd,
207 			struct snd_soc_dai *dai)
208 {
209 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
210 	u32 reg;
211 	unsigned long flags;
212 
213 	switch (cmd) {
214 	case SNDRV_PCM_TRIGGER_START:
215 	case SNDRV_PCM_TRIGGER_RESUME:
216 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
217 		reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
218 		reg |= IMG_SPDIF_OUT_CTL_SRT_MASK;
219 		img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
220 		break;
221 	case SNDRV_PCM_TRIGGER_STOP:
222 	case SNDRV_PCM_TRIGGER_SUSPEND:
223 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
224 		spin_lock_irqsave(&spdif->lock, flags);
225 		img_spdif_out_reset(spdif);
226 		spin_unlock_irqrestore(&spdif->lock, flags);
227 		break;
228 	default:
229 		return -EINVAL;
230 	}
231 
232 	return 0;
233 }
234 
235 static int img_spdif_out_hw_params(struct snd_pcm_substream *substream,
236 	struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
237 {
238 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
239 	unsigned int channels;
240 	long pre_div_a, pre_div_b, diff_a, diff_b, rate, clk_rate;
241 	u32 reg;
242 	snd_pcm_format_t format;
243 
244 	rate = params_rate(params);
245 	format = params_format(params);
246 	channels = params_channels(params);
247 
248 	dev_dbg(spdif->dev, "hw_params rate %ld channels %u format %u\n",
249 			rate, channels, format);
250 
251 	if (format != SNDRV_PCM_FORMAT_S32_LE)
252 		return -EINVAL;
253 
254 	if (channels != 2)
255 		return -EINVAL;
256 
257 	pre_div_a = clk_round_rate(spdif->clk_ref, rate * 256);
258 	if (pre_div_a < 0)
259 		return pre_div_a;
260 	pre_div_b = clk_round_rate(spdif->clk_ref, rate * 384);
261 	if (pre_div_b < 0)
262 		return pre_div_b;
263 
264 	diff_a = abs((pre_div_a / 256) - rate);
265 	diff_b = abs((pre_div_b / 384) - rate);
266 
267 	/* If diffs are equal, use lower clock rate */
268 	if (diff_a > diff_b)
269 		clk_set_rate(spdif->clk_ref, pre_div_b);
270 	else
271 		clk_set_rate(spdif->clk_ref, pre_div_a);
272 
273 	/*
274 	 * Another driver (eg machine driver) may have rejected the above
275 	 * change. Get the current rate and set the register bit according to
276 	 * the new min diff
277 	 */
278 	clk_rate = clk_get_rate(spdif->clk_ref);
279 
280 	diff_a = abs((clk_rate / 256) - rate);
281 	diff_b = abs((clk_rate / 384) - rate);
282 
283 	reg = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
284 	if (diff_a <= diff_b)
285 		reg &= ~IMG_SPDIF_OUT_CTL_CLK_MASK;
286 	else
287 		reg |= IMG_SPDIF_OUT_CTL_CLK_MASK;
288 	img_spdif_out_writel(spdif, reg, IMG_SPDIF_OUT_CTL);
289 
290 	return 0;
291 }
292 
293 static const struct snd_soc_dai_ops img_spdif_out_dai_ops = {
294 	.trigger = img_spdif_out_trigger,
295 	.hw_params = img_spdif_out_hw_params
296 };
297 
298 static int img_spdif_out_dai_probe(struct snd_soc_dai *dai)
299 {
300 	struct img_spdif_out *spdif = snd_soc_dai_get_drvdata(dai);
301 
302 	snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);
303 
304 	snd_soc_add_dai_controls(dai, img_spdif_out_controls,
305 			ARRAY_SIZE(img_spdif_out_controls));
306 
307 	return 0;
308 }
309 
310 static struct snd_soc_dai_driver img_spdif_out_dai = {
311 	.probe = img_spdif_out_dai_probe,
312 	.playback = {
313 		.channels_min = 2,
314 		.channels_max = 2,
315 		.rates = SNDRV_PCM_RATE_8000_192000,
316 		.formats = SNDRV_PCM_FMTBIT_S32_LE
317 	},
318 	.ops = &img_spdif_out_dai_ops
319 };
320 
321 static const struct snd_soc_component_driver img_spdif_out_component = {
322 	.name = "img-spdif-out"
323 };
324 
325 static int img_spdif_out_probe(struct platform_device *pdev)
326 {
327 	struct img_spdif_out *spdif;
328 	struct resource *res;
329 	void __iomem *base;
330 	int ret;
331 	struct device *dev = &pdev->dev;
332 
333 	spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);
334 	if (!spdif)
335 		return -ENOMEM;
336 
337 	platform_set_drvdata(pdev, spdif);
338 
339 	spdif->dev = &pdev->dev;
340 
341 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
342 	base = devm_ioremap_resource(&pdev->dev, res);
343 	if (IS_ERR(base))
344 		return PTR_ERR(base);
345 
346 	spdif->base = base;
347 
348 	spdif->rst = devm_reset_control_get_exclusive(&pdev->dev, "rst");
349 	if (IS_ERR(spdif->rst)) {
350 		if (PTR_ERR(spdif->rst) != -EPROBE_DEFER)
351 			dev_err(&pdev->dev, "No top level reset found\n");
352 		return PTR_ERR(spdif->rst);
353 	}
354 
355 	spdif->clk_sys = devm_clk_get(&pdev->dev, "sys");
356 	if (IS_ERR(spdif->clk_sys)) {
357 		if (PTR_ERR(spdif->clk_sys) != -EPROBE_DEFER)
358 			dev_err(dev, "Failed to acquire clock 'sys'\n");
359 		return PTR_ERR(spdif->clk_sys);
360 	}
361 
362 	spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");
363 	if (IS_ERR(spdif->clk_ref)) {
364 		if (PTR_ERR(spdif->clk_ref) != -EPROBE_DEFER)
365 			dev_err(dev, "Failed to acquire clock 'ref'\n");
366 		return PTR_ERR(spdif->clk_ref);
367 	}
368 
369 	pm_runtime_enable(&pdev->dev);
370 	if (!pm_runtime_enabled(&pdev->dev)) {
371 		ret = img_spdif_out_runtime_resume(&pdev->dev);
372 		if (ret)
373 			goto err_pm_disable;
374 	}
375 	ret = pm_runtime_get_sync(&pdev->dev);
376 	if (ret < 0)
377 		goto err_suspend;
378 
379 	img_spdif_out_writel(spdif, IMG_SPDIF_OUT_CTL_FS_MASK,
380 			     IMG_SPDIF_OUT_CTL);
381 
382 	img_spdif_out_reset(spdif);
383 	pm_runtime_put(&pdev->dev);
384 
385 	spin_lock_init(&spdif->lock);
386 
387 	spdif->dma_data.addr = res->start + IMG_SPDIF_OUT_TX_FIFO;
388 	spdif->dma_data.addr_width = 4;
389 	spdif->dma_data.maxburst = 4;
390 
391 	ret = devm_snd_soc_register_component(&pdev->dev,
392 			&img_spdif_out_component,
393 			&img_spdif_out_dai, 1);
394 	if (ret)
395 		goto err_suspend;
396 
397 	ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
398 	if (ret)
399 		goto err_suspend;
400 
401 	dev_dbg(&pdev->dev, "Probe successful\n");
402 
403 	return 0;
404 
405 err_suspend:
406 	if (!pm_runtime_status_suspended(&pdev->dev))
407 		img_spdif_out_runtime_suspend(&pdev->dev);
408 err_pm_disable:
409 	pm_runtime_disable(&pdev->dev);
410 
411 	return ret;
412 }
413 
414 static int img_spdif_out_dev_remove(struct platform_device *pdev)
415 {
416 	pm_runtime_disable(&pdev->dev);
417 	if (!pm_runtime_status_suspended(&pdev->dev))
418 		img_spdif_out_runtime_suspend(&pdev->dev);
419 
420 	return 0;
421 }
422 
423 #ifdef CONFIG_PM_SLEEP
424 static int img_spdif_out_suspend(struct device *dev)
425 {
426 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
427 	int ret;
428 
429 	if (pm_runtime_status_suspended(dev)) {
430 		ret = img_spdif_out_runtime_resume(dev);
431 		if (ret)
432 			return ret;
433 	}
434 
435 	spdif->suspend_ctl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CTL);
436 	spdif->suspend_csl = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSL);
437 	spdif->suspend_csh = img_spdif_out_readl(spdif, IMG_SPDIF_OUT_CSH_UV);
438 
439 	img_spdif_out_runtime_suspend(dev);
440 
441 	return 0;
442 }
443 
444 static int img_spdif_out_resume(struct device *dev)
445 {
446 	struct img_spdif_out *spdif = dev_get_drvdata(dev);
447 	int ret;
448 
449 	ret = img_spdif_out_runtime_resume(dev);
450 	if (ret)
451 		return ret;
452 
453 	img_spdif_out_writel(spdif, spdif->suspend_ctl, IMG_SPDIF_OUT_CTL);
454 	img_spdif_out_writel(spdif, spdif->suspend_csl, IMG_SPDIF_OUT_CSL);
455 	img_spdif_out_writel(spdif, spdif->suspend_csh, IMG_SPDIF_OUT_CSH_UV);
456 
457 	if (pm_runtime_status_suspended(dev))
458 		img_spdif_out_runtime_suspend(dev);
459 
460 	return 0;
461 }
462 #endif
463 static const struct of_device_id img_spdif_out_of_match[] = {
464 	{ .compatible = "img,spdif-out" },
465 	{}
466 };
467 MODULE_DEVICE_TABLE(of, img_spdif_out_of_match);
468 
469 static const struct dev_pm_ops img_spdif_out_pm_ops = {
470 	SET_RUNTIME_PM_OPS(img_spdif_out_runtime_suspend,
471 			   img_spdif_out_runtime_resume, NULL)
472 	SET_SYSTEM_SLEEP_PM_OPS(img_spdif_out_suspend, img_spdif_out_resume)
473 };
474 
475 static struct platform_driver img_spdif_out_driver = {
476 	.driver = {
477 		.name = "img-spdif-out",
478 		.of_match_table = img_spdif_out_of_match,
479 		.pm = &img_spdif_out_pm_ops
480 	},
481 	.probe = img_spdif_out_probe,
482 	.remove = img_spdif_out_dev_remove
483 };
484 module_platform_driver(img_spdif_out_driver);
485 
486 MODULE_AUTHOR("Damien Horsley <Damien.Horsley@imgtec.com>");
487 MODULE_DESCRIPTION("IMG SPDIF Output driver");
488 MODULE_LICENSE("GPL v2");
489