xref: /openbmc/linux/sound/soc/au1x/psc-i2s.c (revision 275876e2)
1 /*
2  * Au12x0/Au1550 PSC ALSA ASoC audio support.
3  *
4  * (c) 2007-2008 MSC Vertriebsges.m.b.H.,
5  *	Manuel Lauss <manuel.lauss@gmail.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * Au1xxx-PSC I2S glue.
12  *
13  * NOTE: so far only PSC slave mode (bit- and frameclock) is supported.
14  */
15 
16 #include <linux/init.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
19 #include <linux/suspend.h>
20 #include <sound/core.h>
21 #include <sound/pcm.h>
22 #include <sound/initval.h>
23 #include <sound/soc.h>
24 #include <asm/mach-au1x00/au1000.h>
25 #include <asm/mach-au1x00/au1xxx_psc.h>
26 
27 #include "psc.h"
28 
29 /* supported I2S DAI hardware formats */
30 #define AU1XPSC_I2S_DAIFMT \
31 	(SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_LEFT_J |	\
32 	 SND_SOC_DAIFMT_NB_NF)
33 
34 /* supported I2S direction */
35 #define AU1XPSC_I2S_DIR \
36 	(SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
37 
38 #define AU1XPSC_I2S_RATES \
39 	SNDRV_PCM_RATE_8000_192000
40 
41 #define AU1XPSC_I2S_FMTS \
42 	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE)
43 
44 #define I2SSTAT_BUSY(stype)	\
45 	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_I2SSTAT_TB : PSC_I2SSTAT_RB)
46 #define I2SPCR_START(stype)	\
47 	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_I2SPCR_TS : PSC_I2SPCR_RS)
48 #define I2SPCR_STOP(stype)	\
49 	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_I2SPCR_TP : PSC_I2SPCR_RP)
50 #define I2SPCR_CLRFIFO(stype)	\
51 	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_I2SPCR_TC : PSC_I2SPCR_RC)
52 
53 
54 static int au1xpsc_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
55 			       unsigned int fmt)
56 {
57 	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(cpu_dai);
58 	unsigned long ct;
59 	int ret;
60 
61 	ret = -EINVAL;
62 
63 	ct = pscdata->cfg;
64 
65 	ct &= ~(PSC_I2SCFG_XM | PSC_I2SCFG_MLJ);	/* left-justified */
66 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
67 	case SND_SOC_DAIFMT_I2S:
68 		ct |= PSC_I2SCFG_XM;	/* enable I2S mode */
69 		break;
70 	case SND_SOC_DAIFMT_MSB:
71 		break;
72 	case SND_SOC_DAIFMT_LSB:
73 		ct |= PSC_I2SCFG_MLJ;	/* LSB (right-) justified */
74 		break;
75 	default:
76 		goto out;
77 	}
78 
79 	ct &= ~(PSC_I2SCFG_BI | PSC_I2SCFG_WI);		/* IB-IF */
80 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
81 	case SND_SOC_DAIFMT_NB_NF:
82 		ct |= PSC_I2SCFG_BI | PSC_I2SCFG_WI;
83 		break;
84 	case SND_SOC_DAIFMT_NB_IF:
85 		ct |= PSC_I2SCFG_BI;
86 		break;
87 	case SND_SOC_DAIFMT_IB_NF:
88 		ct |= PSC_I2SCFG_WI;
89 		break;
90 	case SND_SOC_DAIFMT_IB_IF:
91 		break;
92 	default:
93 		goto out;
94 	}
95 
96 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
97 	case SND_SOC_DAIFMT_CBM_CFM:	/* CODEC master */
98 		ct |= PSC_I2SCFG_MS;	/* PSC I2S slave mode */
99 		break;
100 	case SND_SOC_DAIFMT_CBS_CFS:	/* CODEC slave */
101 		ct &= ~PSC_I2SCFG_MS;	/* PSC I2S Master mode */
102 		break;
103 	default:
104 		goto out;
105 	}
106 
107 	pscdata->cfg = ct;
108 	ret = 0;
109 out:
110 	return ret;
111 }
112 
113 static int au1xpsc_i2s_hw_params(struct snd_pcm_substream *substream,
114 				 struct snd_pcm_hw_params *params,
115 				 struct snd_soc_dai *dai)
116 {
117 	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
118 
119 	int cfgbits;
120 	unsigned long stat;
121 
122 	/* check if the PSC is already streaming data */
123 	stat = __raw_readl(I2S_STAT(pscdata));
124 	if (stat & (PSC_I2SSTAT_TB | PSC_I2SSTAT_RB)) {
125 		/* reject parameters not currently set up in hardware */
126 		cfgbits = __raw_readl(I2S_CFG(pscdata));
127 		if ((PSC_I2SCFG_GET_LEN(cfgbits) != params->msbits) ||
128 		    (params_rate(params) != pscdata->rate))
129 			return -EINVAL;
130 	} else {
131 		/* set sample bitdepth */
132 		pscdata->cfg &= ~(0x1f << 4);
133 		pscdata->cfg |= PSC_I2SCFG_SET_LEN(params->msbits);
134 		/* remember current rate for other stream */
135 		pscdata->rate = params_rate(params);
136 	}
137 	return 0;
138 }
139 
140 /* Configure PSC late:  on my devel systems the codec  is I2S master and
141  * supplies the i2sbitclock __AND__ i2sMclk (!) to the PSC unit.  ASoC
142  * uses aggressive PM and  switches the codec off  when it is not in use
143  * which also means the PSC unit doesn't get any clocks and is therefore
144  * dead. That's why this chunk here gets called from the trigger callback
145  * because I can be reasonably certain the codec is driving the clocks.
146  */
147 static int au1xpsc_i2s_configure(struct au1xpsc_audio_data *pscdata)
148 {
149 	unsigned long tmo;
150 
151 	/* bring PSC out of sleep, and configure I2S unit */
152 	__raw_writel(PSC_CTRL_ENABLE, PSC_CTRL(pscdata));
153 	wmb(); /* drain writebuffer */
154 
155 	tmo = 1000000;
156 	while (!(__raw_readl(I2S_STAT(pscdata)) & PSC_I2SSTAT_SR) && tmo)
157 		tmo--;
158 
159 	if (!tmo)
160 		goto psc_err;
161 
162 	__raw_writel(0, I2S_CFG(pscdata));
163 	wmb(); /* drain writebuffer */
164 	__raw_writel(pscdata->cfg | PSC_I2SCFG_DE_ENABLE, I2S_CFG(pscdata));
165 	wmb(); /* drain writebuffer */
166 
167 	/* wait for I2S controller to become ready */
168 	tmo = 1000000;
169 	while (!(__raw_readl(I2S_STAT(pscdata)) & PSC_I2SSTAT_DR) && tmo)
170 		tmo--;
171 
172 	if (tmo)
173 		return 0;
174 
175 psc_err:
176 	__raw_writel(0, I2S_CFG(pscdata));
177 	__raw_writel(PSC_CTRL_SUSPEND, PSC_CTRL(pscdata));
178 	wmb(); /* drain writebuffer */
179 	return -ETIMEDOUT;
180 }
181 
182 static int au1xpsc_i2s_start(struct au1xpsc_audio_data *pscdata, int stype)
183 {
184 	unsigned long tmo, stat;
185 	int ret;
186 
187 	ret = 0;
188 
189 	/* if both TX and RX are idle, configure the PSC  */
190 	stat = __raw_readl(I2S_STAT(pscdata));
191 	if (!(stat & (PSC_I2SSTAT_TB | PSC_I2SSTAT_RB))) {
192 		ret = au1xpsc_i2s_configure(pscdata);
193 		if (ret)
194 			goto out;
195 	}
196 
197 	__raw_writel(I2SPCR_CLRFIFO(stype), I2S_PCR(pscdata));
198 	wmb(); /* drain writebuffer */
199 	__raw_writel(I2SPCR_START(stype), I2S_PCR(pscdata));
200 	wmb(); /* drain writebuffer */
201 
202 	/* wait for start confirmation */
203 	tmo = 1000000;
204 	while (!(__raw_readl(I2S_STAT(pscdata)) & I2SSTAT_BUSY(stype)) && tmo)
205 		tmo--;
206 
207 	if (!tmo) {
208 		__raw_writel(I2SPCR_STOP(stype), I2S_PCR(pscdata));
209 		wmb(); /* drain writebuffer */
210 		ret = -ETIMEDOUT;
211 	}
212 out:
213 	return ret;
214 }
215 
216 static int au1xpsc_i2s_stop(struct au1xpsc_audio_data *pscdata, int stype)
217 {
218 	unsigned long tmo, stat;
219 
220 	__raw_writel(I2SPCR_STOP(stype), I2S_PCR(pscdata));
221 	wmb(); /* drain writebuffer */
222 
223 	/* wait for stop confirmation */
224 	tmo = 1000000;
225 	while ((__raw_readl(I2S_STAT(pscdata)) & I2SSTAT_BUSY(stype)) && tmo)
226 		tmo--;
227 
228 	/* if both TX and RX are idle, disable PSC */
229 	stat = __raw_readl(I2S_STAT(pscdata));
230 	if (!(stat & (PSC_I2SSTAT_TB | PSC_I2SSTAT_RB))) {
231 		__raw_writel(0, I2S_CFG(pscdata));
232 		wmb(); /* drain writebuffer */
233 		__raw_writel(PSC_CTRL_SUSPEND, PSC_CTRL(pscdata));
234 		wmb(); /* drain writebuffer */
235 	}
236 	return 0;
237 }
238 
239 static int au1xpsc_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
240 			       struct snd_soc_dai *dai)
241 {
242 	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
243 	int ret, stype = substream->stream;
244 
245 	switch (cmd) {
246 	case SNDRV_PCM_TRIGGER_START:
247 	case SNDRV_PCM_TRIGGER_RESUME:
248 		ret = au1xpsc_i2s_start(pscdata, stype);
249 		break;
250 	case SNDRV_PCM_TRIGGER_STOP:
251 	case SNDRV_PCM_TRIGGER_SUSPEND:
252 		ret = au1xpsc_i2s_stop(pscdata, stype);
253 		break;
254 	default:
255 		ret = -EINVAL;
256 	}
257 	return ret;
258 }
259 
260 static int au1xpsc_i2s_startup(struct snd_pcm_substream *substream,
261 			       struct snd_soc_dai *dai)
262 {
263 	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
264 	snd_soc_dai_set_dma_data(dai, substream, &pscdata->dmaids[0]);
265 	return 0;
266 }
267 
268 static const struct snd_soc_dai_ops au1xpsc_i2s_dai_ops = {
269 	.startup	= au1xpsc_i2s_startup,
270 	.trigger	= au1xpsc_i2s_trigger,
271 	.hw_params	= au1xpsc_i2s_hw_params,
272 	.set_fmt	= au1xpsc_i2s_set_fmt,
273 };
274 
275 static const struct snd_soc_dai_driver au1xpsc_i2s_dai_template = {
276 	.playback = {
277 		.rates		= AU1XPSC_I2S_RATES,
278 		.formats	= AU1XPSC_I2S_FMTS,
279 		.channels_min	= 2,
280 		.channels_max	= 8,	/* 2 without external help */
281 	},
282 	.capture = {
283 		.rates		= AU1XPSC_I2S_RATES,
284 		.formats	= AU1XPSC_I2S_FMTS,
285 		.channels_min	= 2,
286 		.channels_max	= 8,	/* 2 without external help */
287 	},
288 	.ops = &au1xpsc_i2s_dai_ops,
289 };
290 
291 static const struct snd_soc_component_driver au1xpsc_i2s_component = {
292 	.name		= "au1xpsc-i2s",
293 };
294 
295 static int au1xpsc_i2s_drvprobe(struct platform_device *pdev)
296 {
297 	struct resource *iores, *dmares;
298 	unsigned long sel;
299 	int ret;
300 	struct au1xpsc_audio_data *wd;
301 
302 	wd = devm_kzalloc(&pdev->dev, sizeof(struct au1xpsc_audio_data),
303 			  GFP_KERNEL);
304 	if (!wd)
305 		return -ENOMEM;
306 
307 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
308 	if (!iores)
309 		return -ENODEV;
310 
311 	ret = -EBUSY;
312 	if (!devm_request_mem_region(&pdev->dev, iores->start,
313 				     resource_size(iores),
314 				     pdev->name))
315 		return -EBUSY;
316 
317 	wd->mmio = devm_ioremap(&pdev->dev, iores->start,
318 				resource_size(iores));
319 	if (!wd->mmio)
320 		return -EBUSY;
321 
322 	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
323 	if (!dmares)
324 		return -EBUSY;
325 	wd->dmaids[SNDRV_PCM_STREAM_PLAYBACK] = dmares->start;
326 
327 	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 1);
328 	if (!dmares)
329 		return -EBUSY;
330 	wd->dmaids[SNDRV_PCM_STREAM_CAPTURE] = dmares->start;
331 
332 	/* preserve PSC clock source set up by platform (dev.platform_data
333 	 * is already occupied by soc layer)
334 	 */
335 	sel = __raw_readl(PSC_SEL(wd)) & PSC_SEL_CLK_MASK;
336 	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
337 	wmb(); /* drain writebuffer */
338 	__raw_writel(PSC_SEL_PS_I2SMODE | sel, PSC_SEL(wd));
339 	__raw_writel(0, I2S_CFG(wd));
340 	wmb(); /* drain writebuffer */
341 
342 	/* preconfigure: set max rx/tx fifo depths */
343 	wd->cfg |= PSC_I2SCFG_RT_FIFO8 | PSC_I2SCFG_TT_FIFO8;
344 
345 	/* don't wait for I2S core to become ready now; clocks may not
346 	 * be running yet; depending on clock input for PSC a wait might
347 	 * time out.
348 	 */
349 
350 	/* name the DAI like this device instance ("au1xpsc-i2s.PSCINDEX") */
351 	memcpy(&wd->dai_drv, &au1xpsc_i2s_dai_template,
352 	       sizeof(struct snd_soc_dai_driver));
353 	wd->dai_drv.name = dev_name(&pdev->dev);
354 
355 	platform_set_drvdata(pdev, wd);
356 
357 	return snd_soc_register_component(&pdev->dev, &au1xpsc_i2s_component,
358 					  &wd->dai_drv, 1);
359 }
360 
361 static int au1xpsc_i2s_drvremove(struct platform_device *pdev)
362 {
363 	struct au1xpsc_audio_data *wd = platform_get_drvdata(pdev);
364 
365 	snd_soc_unregister_component(&pdev->dev);
366 
367 	__raw_writel(0, I2S_CFG(wd));
368 	wmb(); /* drain writebuffer */
369 	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
370 	wmb(); /* drain writebuffer */
371 
372 	return 0;
373 }
374 
375 #ifdef CONFIG_PM
376 static int au1xpsc_i2s_drvsuspend(struct device *dev)
377 {
378 	struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
379 
380 	/* save interesting register and disable PSC */
381 	wd->pm[0] = __raw_readl(PSC_SEL(wd));
382 
383 	__raw_writel(0, I2S_CFG(wd));
384 	wmb(); /* drain writebuffer */
385 	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
386 	wmb(); /* drain writebuffer */
387 
388 	return 0;
389 }
390 
391 static int au1xpsc_i2s_drvresume(struct device *dev)
392 {
393 	struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
394 
395 	/* select I2S mode and PSC clock */
396 	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
397 	wmb(); /* drain writebuffer */
398 	__raw_writel(0, PSC_SEL(wd));
399 	wmb(); /* drain writebuffer */
400 	__raw_writel(wd->pm[0], PSC_SEL(wd));
401 	wmb(); /* drain writebuffer */
402 
403 	return 0;
404 }
405 
406 static struct dev_pm_ops au1xpsci2s_pmops = {
407 	.suspend	= au1xpsc_i2s_drvsuspend,
408 	.resume		= au1xpsc_i2s_drvresume,
409 };
410 
411 #define AU1XPSCI2S_PMOPS &au1xpsci2s_pmops
412 
413 #else
414 
415 #define AU1XPSCI2S_PMOPS NULL
416 
417 #endif
418 
419 static struct platform_driver au1xpsc_i2s_driver = {
420 	.driver		= {
421 		.name	= "au1xpsc_i2s",
422 		.owner	= THIS_MODULE,
423 		.pm	= AU1XPSCI2S_PMOPS,
424 	},
425 	.probe		= au1xpsc_i2s_drvprobe,
426 	.remove		= au1xpsc_i2s_drvremove,
427 };
428 
429 module_platform_driver(au1xpsc_i2s_driver);
430 
431 MODULE_LICENSE("GPL");
432 MODULE_DESCRIPTION("Au12x0/Au1550 PSC I2S ALSA ASoC audio driver");
433 MODULE_AUTHOR("Manuel Lauss");
434