xref: /openbmc/linux/sound/soc/cirrus/ep93xx-i2s.c (revision 861e10be)
1 /*
2  * linux/sound/soc/ep93xx-i2s.c
3  * EP93xx I2S driver
4  *
5  * Copyright (C) 2010 Ryan Mallon
6  *
7  * Based on the original driver by:
8  *   Copyright (C) 2007 Chase Douglas <chasedouglas@gmail>
9  *   Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License version 2 as
13  * published by the Free Software Foundation.
14  *
15  */
16 
17 #include <linux/module.h>
18 #include <linux/init.h>
19 #include <linux/slab.h>
20 #include <linux/clk.h>
21 #include <linux/io.h>
22 
23 #include <sound/core.h>
24 #include <sound/pcm.h>
25 #include <sound/pcm_params.h>
26 #include <sound/initval.h>
27 #include <sound/soc.h>
28 
29 #include <mach/hardware.h>
30 #include <mach/ep93xx-regs.h>
31 #include <linux/platform_data/dma-ep93xx.h>
32 
33 #include "ep93xx-pcm.h"
34 
35 #define EP93XX_I2S_TXCLKCFG		0x00
36 #define EP93XX_I2S_RXCLKCFG		0x04
37 #define EP93XX_I2S_GLCTRL		0x0C
38 
39 #define EP93XX_I2S_TXLINCTRLDATA	0x28
40 #define EP93XX_I2S_TXCTRL		0x2C
41 #define EP93XX_I2S_TXWRDLEN		0x30
42 #define EP93XX_I2S_TX0EN		0x34
43 
44 #define EP93XX_I2S_RXLINCTRLDATA	0x58
45 #define EP93XX_I2S_RXCTRL		0x5C
46 #define EP93XX_I2S_RXWRDLEN		0x60
47 #define EP93XX_I2S_RX0EN		0x64
48 
49 #define EP93XX_I2S_WRDLEN_16		(0 << 0)
50 #define EP93XX_I2S_WRDLEN_24		(1 << 0)
51 #define EP93XX_I2S_WRDLEN_32		(2 << 0)
52 
53 #define EP93XX_I2S_LINCTRLDATA_R_JUST	(1 << 2) /* Right justify */
54 
55 #define EP93XX_I2S_CLKCFG_LRS		(1 << 0) /* lrclk polarity */
56 #define EP93XX_I2S_CLKCFG_CKP		(1 << 1) /* Bit clock polarity */
57 #define EP93XX_I2S_CLKCFG_REL		(1 << 2) /* First bit transition */
58 #define EP93XX_I2S_CLKCFG_MASTER	(1 << 3) /* Master mode */
59 #define EP93XX_I2S_CLKCFG_NBCG		(1 << 4) /* Not bit clock gating */
60 
61 struct ep93xx_i2s_info {
62 	struct clk			*mclk;
63 	struct clk			*sclk;
64 	struct clk			*lrclk;
65 	struct ep93xx_pcm_dma_params	*dma_params;
66 	void __iomem			*regs;
67 };
68 
69 struct ep93xx_pcm_dma_params ep93xx_i2s_dma_params[] = {
70 	[SNDRV_PCM_STREAM_PLAYBACK] = {
71 		.name		= "i2s-pcm-out",
72 		.dma_port	= EP93XX_DMA_I2S1,
73 	},
74 	[SNDRV_PCM_STREAM_CAPTURE] = {
75 		.name		= "i2s-pcm-in",
76 		.dma_port	= EP93XX_DMA_I2S1,
77 	},
78 };
79 
80 static inline void ep93xx_i2s_write_reg(struct ep93xx_i2s_info *info,
81 					unsigned reg, unsigned val)
82 {
83 	__raw_writel(val, info->regs + reg);
84 }
85 
86 static inline unsigned ep93xx_i2s_read_reg(struct ep93xx_i2s_info *info,
87 					   unsigned reg)
88 {
89 	return __raw_readl(info->regs + reg);
90 }
91 
92 static void ep93xx_i2s_enable(struct ep93xx_i2s_info *info, int stream)
93 {
94 	unsigned base_reg;
95 	int i;
96 
97 	if ((ep93xx_i2s_read_reg(info, EP93XX_I2S_TX0EN) & 0x1) == 0 &&
98 	    (ep93xx_i2s_read_reg(info, EP93XX_I2S_RX0EN) & 0x1) == 0) {
99 		/* Enable clocks */
100 		clk_enable(info->mclk);
101 		clk_enable(info->sclk);
102 		clk_enable(info->lrclk);
103 
104 		/* Enable i2s */
105 		ep93xx_i2s_write_reg(info, EP93XX_I2S_GLCTRL, 1);
106 	}
107 
108 	/* Enable fifos */
109 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
110 		base_reg = EP93XX_I2S_TX0EN;
111 	else
112 		base_reg = EP93XX_I2S_RX0EN;
113 	for (i = 0; i < 3; i++)
114 		ep93xx_i2s_write_reg(info, base_reg + (i * 4), 1);
115 }
116 
117 static void ep93xx_i2s_disable(struct ep93xx_i2s_info *info, int stream)
118 {
119 	unsigned base_reg;
120 	int i;
121 
122 	/* Disable fifos */
123 	if (stream == SNDRV_PCM_STREAM_PLAYBACK)
124 		base_reg = EP93XX_I2S_TX0EN;
125 	else
126 		base_reg = EP93XX_I2S_RX0EN;
127 	for (i = 0; i < 3; i++)
128 		ep93xx_i2s_write_reg(info, base_reg + (i * 4), 0);
129 
130 	if ((ep93xx_i2s_read_reg(info, EP93XX_I2S_TX0EN) & 0x1) == 0 &&
131 	    (ep93xx_i2s_read_reg(info, EP93XX_I2S_RX0EN) & 0x1) == 0) {
132 		/* Disable i2s */
133 		ep93xx_i2s_write_reg(info, EP93XX_I2S_GLCTRL, 0);
134 
135 		/* Disable clocks */
136 		clk_disable(info->lrclk);
137 		clk_disable(info->sclk);
138 		clk_disable(info->mclk);
139 	}
140 }
141 
142 static int ep93xx_i2s_startup(struct snd_pcm_substream *substream,
143 			      struct snd_soc_dai *dai)
144 {
145 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
146 	struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(dai);
147 	struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
148 
149 	snd_soc_dai_set_dma_data(cpu_dai, substream,
150 				 &info->dma_params[substream->stream]);
151 	return 0;
152 }
153 
154 static void ep93xx_i2s_shutdown(struct snd_pcm_substream *substream,
155 				struct snd_soc_dai *dai)
156 {
157 	struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(dai);
158 
159 	ep93xx_i2s_disable(info, substream->stream);
160 }
161 
162 static int ep93xx_i2s_set_dai_fmt(struct snd_soc_dai *cpu_dai,
163 				  unsigned int fmt)
164 {
165 	struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(cpu_dai);
166 	unsigned int clk_cfg, lin_ctrl;
167 
168 	clk_cfg  = ep93xx_i2s_read_reg(info, EP93XX_I2S_RXCLKCFG);
169 	lin_ctrl = ep93xx_i2s_read_reg(info, EP93XX_I2S_RXLINCTRLDATA);
170 
171 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
172 	case SND_SOC_DAIFMT_I2S:
173 		clk_cfg |= EP93XX_I2S_CLKCFG_REL;
174 		lin_ctrl &= ~EP93XX_I2S_LINCTRLDATA_R_JUST;
175 		break;
176 
177 	case SND_SOC_DAIFMT_LEFT_J:
178 		clk_cfg &= ~EP93XX_I2S_CLKCFG_REL;
179 		lin_ctrl &= ~EP93XX_I2S_LINCTRLDATA_R_JUST;
180 		break;
181 
182 	case SND_SOC_DAIFMT_RIGHT_J:
183 		clk_cfg &= ~EP93XX_I2S_CLKCFG_REL;
184 		lin_ctrl |= EP93XX_I2S_LINCTRLDATA_R_JUST;
185 		break;
186 
187 	default:
188 		return -EINVAL;
189 	}
190 
191 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
192 	case SND_SOC_DAIFMT_CBS_CFS:
193 		/* CPU is master */
194 		clk_cfg |= EP93XX_I2S_CLKCFG_MASTER;
195 		break;
196 
197 	case SND_SOC_DAIFMT_CBM_CFM:
198 		/* Codec is master */
199 		clk_cfg &= ~EP93XX_I2S_CLKCFG_MASTER;
200 		break;
201 
202 	default:
203 		return -EINVAL;
204 	}
205 
206 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
207 	case SND_SOC_DAIFMT_NB_NF:
208 		/* Negative bit clock, lrclk low on left word */
209 		clk_cfg &= ~(EP93XX_I2S_CLKCFG_CKP | EP93XX_I2S_CLKCFG_REL);
210 		break;
211 
212 	case SND_SOC_DAIFMT_NB_IF:
213 		/* Negative bit clock, lrclk low on right word */
214 		clk_cfg &= ~EP93XX_I2S_CLKCFG_CKP;
215 		clk_cfg |= EP93XX_I2S_CLKCFG_REL;
216 		break;
217 
218 	case SND_SOC_DAIFMT_IB_NF:
219 		/* Positive bit clock, lrclk low on left word */
220 		clk_cfg |= EP93XX_I2S_CLKCFG_CKP;
221 		clk_cfg &= ~EP93XX_I2S_CLKCFG_REL;
222 		break;
223 
224 	case SND_SOC_DAIFMT_IB_IF:
225 		/* Positive bit clock, lrclk low on right word */
226 		clk_cfg |= EP93XX_I2S_CLKCFG_CKP | EP93XX_I2S_CLKCFG_REL;
227 		break;
228 	}
229 
230 	/* Write new register values */
231 	ep93xx_i2s_write_reg(info, EP93XX_I2S_RXCLKCFG, clk_cfg);
232 	ep93xx_i2s_write_reg(info, EP93XX_I2S_TXCLKCFG, clk_cfg);
233 	ep93xx_i2s_write_reg(info, EP93XX_I2S_RXLINCTRLDATA, lin_ctrl);
234 	ep93xx_i2s_write_reg(info, EP93XX_I2S_TXLINCTRLDATA, lin_ctrl);
235 	return 0;
236 }
237 
238 static int ep93xx_i2s_hw_params(struct snd_pcm_substream *substream,
239 				struct snd_pcm_hw_params *params,
240 				struct snd_soc_dai *dai)
241 {
242 	struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(dai);
243 	unsigned word_len, div, sdiv, lrdiv;
244 	int err;
245 
246 	switch (params_format(params)) {
247 	case SNDRV_PCM_FORMAT_S16_LE:
248 		word_len = EP93XX_I2S_WRDLEN_16;
249 		break;
250 
251 	case SNDRV_PCM_FORMAT_S24_LE:
252 		word_len = EP93XX_I2S_WRDLEN_24;
253 		break;
254 
255 	case SNDRV_PCM_FORMAT_S32_LE:
256 		word_len = EP93XX_I2S_WRDLEN_32;
257 		break;
258 
259 	default:
260 		return -EINVAL;
261 	}
262 
263 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
264 		ep93xx_i2s_write_reg(info, EP93XX_I2S_TXWRDLEN, word_len);
265 	else
266 		ep93xx_i2s_write_reg(info, EP93XX_I2S_RXWRDLEN, word_len);
267 
268 	/*
269 	 * EP93xx I2S module can be setup so SCLK / LRCLK value can be
270 	 * 32, 64, 128. MCLK / SCLK value can be 2 and 4.
271 	 * We set LRCLK equal to `rate' and minimum SCLK / LRCLK
272 	 * value is 64, because our sample size is 32 bit * 2 channels.
273 	 * I2S standard permits us to transmit more bits than
274 	 * the codec uses.
275 	 */
276 	div = clk_get_rate(info->mclk) / params_rate(params);
277 	sdiv = 4;
278 	if (div > (256 + 512) / 2) {
279 		lrdiv = 128;
280 	} else {
281 		lrdiv = 64;
282 		if (div < (128 + 256) / 2)
283 			sdiv = 2;
284 	}
285 
286 	err = clk_set_rate(info->sclk, clk_get_rate(info->mclk) / sdiv);
287 	if (err)
288 		return err;
289 
290 	err = clk_set_rate(info->lrclk, clk_get_rate(info->sclk) / lrdiv);
291 	if (err)
292 		return err;
293 
294 	ep93xx_i2s_enable(info, substream->stream);
295 	return 0;
296 }
297 
298 static int ep93xx_i2s_set_sysclk(struct snd_soc_dai *cpu_dai, int clk_id,
299 				 unsigned int freq, int dir)
300 {
301 	struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(cpu_dai);
302 
303 	if (dir == SND_SOC_CLOCK_IN || clk_id != 0)
304 		return -EINVAL;
305 
306 	return clk_set_rate(info->mclk, freq);
307 }
308 
309 #ifdef CONFIG_PM
310 static int ep93xx_i2s_suspend(struct snd_soc_dai *dai)
311 {
312 	struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(dai);
313 
314 	if (!dai->active)
315 		return 0;
316 
317 	ep93xx_i2s_disable(info, SNDRV_PCM_STREAM_PLAYBACK);
318 	ep93xx_i2s_disable(info, SNDRV_PCM_STREAM_CAPTURE);
319 
320 	return 0;
321 }
322 
323 static int ep93xx_i2s_resume(struct snd_soc_dai *dai)
324 {
325 	struct ep93xx_i2s_info *info = snd_soc_dai_get_drvdata(dai);
326 
327 	if (!dai->active)
328 		return 0;
329 
330 	ep93xx_i2s_enable(info, SNDRV_PCM_STREAM_PLAYBACK);
331 	ep93xx_i2s_enable(info, SNDRV_PCM_STREAM_CAPTURE);
332 
333 	return 0;
334 }
335 #else
336 #define ep93xx_i2s_suspend	NULL
337 #define ep93xx_i2s_resume	NULL
338 #endif
339 
340 static const struct snd_soc_dai_ops ep93xx_i2s_dai_ops = {
341 	.startup	= ep93xx_i2s_startup,
342 	.shutdown	= ep93xx_i2s_shutdown,
343 	.hw_params	= ep93xx_i2s_hw_params,
344 	.set_sysclk	= ep93xx_i2s_set_sysclk,
345 	.set_fmt	= ep93xx_i2s_set_dai_fmt,
346 };
347 
348 #define EP93XX_I2S_FORMATS (SNDRV_PCM_FMTBIT_S32_LE)
349 
350 static struct snd_soc_dai_driver ep93xx_i2s_dai = {
351 	.symmetric_rates= 1,
352 	.suspend	= ep93xx_i2s_suspend,
353 	.resume		= ep93xx_i2s_resume,
354 	.playback	= {
355 		.channels_min	= 2,
356 		.channels_max	= 2,
357 		.rates		= SNDRV_PCM_RATE_8000_192000,
358 		.formats	= EP93XX_I2S_FORMATS,
359 	},
360 	.capture	= {
361 		 .channels_min	= 2,
362 		 .channels_max	= 2,
363 		 .rates		= SNDRV_PCM_RATE_8000_192000,
364 		 .formats	= EP93XX_I2S_FORMATS,
365 	},
366 	.ops		= &ep93xx_i2s_dai_ops,
367 };
368 
369 static int ep93xx_i2s_probe(struct platform_device *pdev)
370 {
371 	struct ep93xx_i2s_info *info;
372 	struct resource *res;
373 	int err;
374 
375 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
376 	if (!info)
377 		return -ENOMEM;
378 
379 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
380 	if (!res)
381 		return -ENODEV;
382 
383 	info->regs = devm_request_and_ioremap(&pdev->dev, res);
384 	if (!info->regs)
385 		return -ENXIO;
386 
387 	info->mclk = clk_get(&pdev->dev, "mclk");
388 	if (IS_ERR(info->mclk)) {
389 		err = PTR_ERR(info->mclk);
390 		goto fail;
391 	}
392 
393 	info->sclk = clk_get(&pdev->dev, "sclk");
394 	if (IS_ERR(info->sclk)) {
395 		err = PTR_ERR(info->sclk);
396 		goto fail_put_mclk;
397 	}
398 
399 	info->lrclk = clk_get(&pdev->dev, "lrclk");
400 	if (IS_ERR(info->lrclk)) {
401 		err = PTR_ERR(info->lrclk);
402 		goto fail_put_sclk;
403 	}
404 
405 	dev_set_drvdata(&pdev->dev, info);
406 	info->dma_params = ep93xx_i2s_dma_params;
407 
408 	err = snd_soc_register_dai(&pdev->dev, &ep93xx_i2s_dai);
409 	if (err)
410 		goto fail_put_lrclk;
411 
412 	return 0;
413 
414 fail_put_lrclk:
415 	dev_set_drvdata(&pdev->dev, NULL);
416 	clk_put(info->lrclk);
417 fail_put_sclk:
418 	clk_put(info->sclk);
419 fail_put_mclk:
420 	clk_put(info->mclk);
421 fail:
422 	return err;
423 }
424 
425 static int ep93xx_i2s_remove(struct platform_device *pdev)
426 {
427 	struct ep93xx_i2s_info *info = dev_get_drvdata(&pdev->dev);
428 
429 	snd_soc_unregister_dai(&pdev->dev);
430 	dev_set_drvdata(&pdev->dev, NULL);
431 	clk_put(info->lrclk);
432 	clk_put(info->sclk);
433 	clk_put(info->mclk);
434 	return 0;
435 }
436 
437 static struct platform_driver ep93xx_i2s_driver = {
438 	.probe	= ep93xx_i2s_probe,
439 	.remove	= ep93xx_i2s_remove,
440 	.driver	= {
441 		.name	= "ep93xx-i2s",
442 		.owner	= THIS_MODULE,
443 	},
444 };
445 
446 module_platform_driver(ep93xx_i2s_driver);
447 
448 MODULE_ALIAS("platform:ep93xx-i2s");
449 MODULE_AUTHOR("Ryan Mallon");
450 MODULE_DESCRIPTION("EP93XX I2S driver");
451 MODULE_LICENSE("GPL");
452