xref: /openbmc/linux/sound/soc/au1x/psc-i2s.c (revision b627b4ed)
1 /*
2  * Au12x0/Au1550 PSC ALSA ASoC audio support.
3  *
4  * (c) 2007-2008 MSC Vertriebsges.m.b.H.,
5  *	Manuel Lauss <mano@roarinelk.homelinux.net>
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: all of these drivers can only work with a SINGLE instance
14  *	 of a PSC. Multiple independent audio devices are impossible
15  *	 with ASoC v1.
16  * NOTE: so far only PSC slave mode (bit- and frameclock) is supported.
17  */
18 
19 #include <linux/init.h>
20 #include <linux/module.h>
21 #include <linux/suspend.h>
22 #include <sound/core.h>
23 #include <sound/pcm.h>
24 #include <sound/initval.h>
25 #include <sound/soc.h>
26 #include <asm/mach-au1x00/au1000.h>
27 #include <asm/mach-au1x00/au1xxx_psc.h>
28 
29 #include "psc.h"
30 
31 /* supported I2S DAI hardware formats */
32 #define AU1XPSC_I2S_DAIFMT \
33 	(SND_SOC_DAIFMT_I2S | SND_SOC_DAIFMT_LEFT_J |	\
34 	 SND_SOC_DAIFMT_NB_NF)
35 
36 /* supported I2S direction */
37 #define AU1XPSC_I2S_DIR \
38 	(SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
39 
40 #define AU1XPSC_I2S_RATES \
41 	SNDRV_PCM_RATE_8000_192000
42 
43 #define AU1XPSC_I2S_FMTS \
44 	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S24_LE)
45 
46 #define I2SSTAT_BUSY(stype)	\
47 	((stype) == PCM_TX ? PSC_I2SSTAT_TB : PSC_I2SSTAT_RB)
48 #define I2SPCR_START(stype)	\
49 	((stype) == PCM_TX ? PSC_I2SPCR_TS : PSC_I2SPCR_RS)
50 #define I2SPCR_STOP(stype)	\
51 	((stype) == PCM_TX ? PSC_I2SPCR_TP : PSC_I2SPCR_RP)
52 #define I2SPCR_CLRFIFO(stype)	\
53 	((stype) == PCM_TX ? PSC_I2SPCR_TC : PSC_I2SPCR_RC)
54 
55 
56 /* instance data. There can be only one, MacLeod!!!! */
57 static struct au1xpsc_audio_data *au1xpsc_i2s_workdata;
58 
59 static int au1xpsc_i2s_set_fmt(struct snd_soc_dai *cpu_dai,
60 			       unsigned int fmt)
61 {
62 	struct au1xpsc_audio_data *pscdata = au1xpsc_i2s_workdata;
63 	unsigned long ct;
64 	int ret;
65 
66 	ret = -EINVAL;
67 
68 	ct = pscdata->cfg;
69 
70 	ct &= ~(PSC_I2SCFG_XM | PSC_I2SCFG_MLJ);	/* left-justified */
71 	switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
72 	case SND_SOC_DAIFMT_I2S:
73 		ct |= PSC_I2SCFG_XM;	/* enable I2S mode */
74 		break;
75 	case SND_SOC_DAIFMT_MSB:
76 		break;
77 	case SND_SOC_DAIFMT_LSB:
78 		ct |= PSC_I2SCFG_MLJ;	/* LSB (right-) justified */
79 		break;
80 	default:
81 		goto out;
82 	}
83 
84 	ct &= ~(PSC_I2SCFG_BI | PSC_I2SCFG_WI);		/* IB-IF */
85 	switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
86 	case SND_SOC_DAIFMT_NB_NF:
87 		ct |= PSC_I2SCFG_BI | PSC_I2SCFG_WI;
88 		break;
89 	case SND_SOC_DAIFMT_NB_IF:
90 		ct |= PSC_I2SCFG_BI;
91 		break;
92 	case SND_SOC_DAIFMT_IB_NF:
93 		ct |= PSC_I2SCFG_WI;
94 		break;
95 	case SND_SOC_DAIFMT_IB_IF:
96 		break;
97 	default:
98 		goto out;
99 	}
100 
101 	switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
102 	case SND_SOC_DAIFMT_CBM_CFM:	/* CODEC master */
103 		ct |= PSC_I2SCFG_MS;	/* PSC I2S slave mode */
104 		break;
105 	case SND_SOC_DAIFMT_CBS_CFS:	/* CODEC slave */
106 		ct &= ~PSC_I2SCFG_MS;	/* PSC I2S Master mode */
107 		break;
108 	default:
109 		goto out;
110 	}
111 
112 	pscdata->cfg = ct;
113 	ret = 0;
114 out:
115 	return ret;
116 }
117 
118 static int au1xpsc_i2s_hw_params(struct snd_pcm_substream *substream,
119 				 struct snd_pcm_hw_params *params,
120 				 struct snd_soc_dai *dai)
121 {
122 	struct au1xpsc_audio_data *pscdata = au1xpsc_i2s_workdata;
123 
124 	int cfgbits;
125 	unsigned long stat;
126 
127 	/* check if the PSC is already streaming data */
128 	stat = au_readl(I2S_STAT(pscdata));
129 	if (stat & (PSC_I2SSTAT_TB | PSC_I2SSTAT_RB)) {
130 		/* reject parameters not currently set up in hardware */
131 		cfgbits = au_readl(I2S_CFG(pscdata));
132 		if ((PSC_I2SCFG_GET_LEN(cfgbits) != params->msbits) ||
133 		    (params_rate(params) != pscdata->rate))
134 			return -EINVAL;
135 	} else {
136 		/* set sample bitdepth */
137 		pscdata->cfg &= ~(0x1f << 4);
138 		pscdata->cfg |= PSC_I2SCFG_SET_LEN(params->msbits);
139 		/* remember current rate for other stream */
140 		pscdata->rate = params_rate(params);
141 	}
142 	return 0;
143 }
144 
145 /* Configure PSC late:  on my devel systems the codec  is I2S master and
146  * supplies the i2sbitclock __AND__ i2sMclk (!) to the PSC unit.  ASoC
147  * uses aggressive PM and  switches the codec off  when it is not in use
148  * which also means the PSC unit doesn't get any clocks and is therefore
149  * dead. That's why this chunk here gets called from the trigger callback
150  * because I can be reasonably certain the codec is driving the clocks.
151  */
152 static int au1xpsc_i2s_configure(struct au1xpsc_audio_data *pscdata)
153 {
154 	unsigned long tmo;
155 
156 	/* bring PSC out of sleep, and configure I2S unit */
157 	au_writel(PSC_CTRL_ENABLE, PSC_CTRL(pscdata));
158 	au_sync();
159 
160 	tmo = 1000000;
161 	while (!(au_readl(I2S_STAT(pscdata)) & PSC_I2SSTAT_SR) && tmo)
162 		tmo--;
163 
164 	if (!tmo)
165 		goto psc_err;
166 
167 	au_writel(0, I2S_CFG(pscdata));
168 	au_sync();
169 	au_writel(pscdata->cfg | PSC_I2SCFG_DE_ENABLE, I2S_CFG(pscdata));
170 	au_sync();
171 
172 	/* wait for I2S controller to become ready */
173 	tmo = 1000000;
174 	while (!(au_readl(I2S_STAT(pscdata)) & PSC_I2SSTAT_DR) && tmo)
175 		tmo--;
176 
177 	if (tmo)
178 		return 0;
179 
180 psc_err:
181 	au_writel(0, I2S_CFG(pscdata));
182 	au_writel(PSC_CTRL_SUSPEND, PSC_CTRL(pscdata));
183 	au_sync();
184 	return -ETIMEDOUT;
185 }
186 
187 static int au1xpsc_i2s_start(struct au1xpsc_audio_data *pscdata, int stype)
188 {
189 	unsigned long tmo, stat;
190 	int ret;
191 
192 	ret = 0;
193 
194 	/* if both TX and RX are idle, configure the PSC  */
195 	stat = au_readl(I2S_STAT(pscdata));
196 	if (!(stat & (PSC_I2SSTAT_TB | PSC_I2SSTAT_RB))) {
197 		ret = au1xpsc_i2s_configure(pscdata);
198 		if (ret)
199 			goto out;
200 	}
201 
202 	au_writel(I2SPCR_CLRFIFO(stype), I2S_PCR(pscdata));
203 	au_sync();
204 	au_writel(I2SPCR_START(stype), I2S_PCR(pscdata));
205 	au_sync();
206 
207 	/* wait for start confirmation */
208 	tmo = 1000000;
209 	while (!(au_readl(I2S_STAT(pscdata)) & I2SSTAT_BUSY(stype)) && tmo)
210 		tmo--;
211 
212 	if (!tmo) {
213 		au_writel(I2SPCR_STOP(stype), I2S_PCR(pscdata));
214 		au_sync();
215 		ret = -ETIMEDOUT;
216 	}
217 out:
218 	return ret;
219 }
220 
221 static int au1xpsc_i2s_stop(struct au1xpsc_audio_data *pscdata, int stype)
222 {
223 	unsigned long tmo, stat;
224 
225 	au_writel(I2SPCR_STOP(stype), I2S_PCR(pscdata));
226 	au_sync();
227 
228 	/* wait for stop confirmation */
229 	tmo = 1000000;
230 	while ((au_readl(I2S_STAT(pscdata)) & I2SSTAT_BUSY(stype)) && tmo)
231 		tmo--;
232 
233 	/* if both TX and RX are idle, disable PSC */
234 	stat = au_readl(I2S_STAT(pscdata));
235 	if (!(stat & (PSC_I2SSTAT_TB | PSC_I2SSTAT_RB))) {
236 		au_writel(0, I2S_CFG(pscdata));
237 		au_sync();
238 		au_writel(PSC_CTRL_SUSPEND, PSC_CTRL(pscdata));
239 		au_sync();
240 	}
241 	return 0;
242 }
243 
244 static int au1xpsc_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
245 			       struct snd_soc_dai *dai)
246 {
247 	struct au1xpsc_audio_data *pscdata = au1xpsc_i2s_workdata;
248 	int ret, stype = SUBSTREAM_TYPE(substream);
249 
250 	switch (cmd) {
251 	case SNDRV_PCM_TRIGGER_START:
252 	case SNDRV_PCM_TRIGGER_RESUME:
253 		ret = au1xpsc_i2s_start(pscdata, stype);
254 		break;
255 	case SNDRV_PCM_TRIGGER_STOP:
256 	case SNDRV_PCM_TRIGGER_SUSPEND:
257 		ret = au1xpsc_i2s_stop(pscdata, stype);
258 		break;
259 	default:
260 		ret = -EINVAL;
261 	}
262 	return ret;
263 }
264 
265 static int au1xpsc_i2s_probe(struct platform_device *pdev,
266 			     struct snd_soc_dai *dai)
267 {
268 	struct resource *r;
269 	unsigned long sel;
270 	int ret;
271 
272 	if (au1xpsc_i2s_workdata)
273 		return -EBUSY;
274 
275 	au1xpsc_i2s_workdata =
276 		kzalloc(sizeof(struct au1xpsc_audio_data), GFP_KERNEL);
277 	if (!au1xpsc_i2s_workdata)
278 		return -ENOMEM;
279 
280 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
281 	if (!r) {
282 		ret = -ENODEV;
283 		goto out0;
284 	}
285 
286 	ret = -EBUSY;
287 	au1xpsc_i2s_workdata->ioarea =
288 		request_mem_region(r->start, r->end - r->start + 1,
289 					"au1xpsc_i2s");
290 	if (!au1xpsc_i2s_workdata->ioarea)
291 		goto out0;
292 
293 	au1xpsc_i2s_workdata->mmio = ioremap(r->start, 0xffff);
294 	if (!au1xpsc_i2s_workdata->mmio)
295 		goto out1;
296 
297 	/* preserve PSC clock source set up by platform (dev.platform_data
298 	 * is already occupied by soc layer)
299 	 */
300 	sel = au_readl(PSC_SEL(au1xpsc_i2s_workdata)) & PSC_SEL_CLK_MASK;
301 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_i2s_workdata));
302 	au_sync();
303 	au_writel(PSC_SEL_PS_I2SMODE | sel, PSC_SEL(au1xpsc_i2s_workdata));
304 	au_writel(0, I2S_CFG(au1xpsc_i2s_workdata));
305 	au_sync();
306 
307 	/* preconfigure: set max rx/tx fifo depths */
308 	au1xpsc_i2s_workdata->cfg |=
309 			PSC_I2SCFG_RT_FIFO8 | PSC_I2SCFG_TT_FIFO8;
310 
311 	/* don't wait for I2S core to become ready now; clocks may not
312 	 * be running yet; depending on clock input for PSC a wait might
313 	 * time out.
314 	 */
315 
316 	return 0;
317 
318 out1:
319 	release_resource(au1xpsc_i2s_workdata->ioarea);
320 	kfree(au1xpsc_i2s_workdata->ioarea);
321 out0:
322 	kfree(au1xpsc_i2s_workdata);
323 	au1xpsc_i2s_workdata = NULL;
324 	return ret;
325 }
326 
327 static void au1xpsc_i2s_remove(struct platform_device *pdev,
328 			       struct snd_soc_dai *dai)
329 {
330 	au_writel(0, I2S_CFG(au1xpsc_i2s_workdata));
331 	au_sync();
332 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_i2s_workdata));
333 	au_sync();
334 
335 	iounmap(au1xpsc_i2s_workdata->mmio);
336 	release_resource(au1xpsc_i2s_workdata->ioarea);
337 	kfree(au1xpsc_i2s_workdata->ioarea);
338 	kfree(au1xpsc_i2s_workdata);
339 	au1xpsc_i2s_workdata = NULL;
340 }
341 
342 static int au1xpsc_i2s_suspend(struct snd_soc_dai *cpu_dai)
343 {
344 	/* save interesting register and disable PSC */
345 	au1xpsc_i2s_workdata->pm[0] =
346 		au_readl(PSC_SEL(au1xpsc_i2s_workdata));
347 
348 	au_writel(0, I2S_CFG(au1xpsc_i2s_workdata));
349 	au_sync();
350 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_i2s_workdata));
351 	au_sync();
352 
353 	return 0;
354 }
355 
356 static int au1xpsc_i2s_resume(struct snd_soc_dai *cpu_dai)
357 {
358 	/* select I2S mode and PSC clock */
359 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_i2s_workdata));
360 	au_sync();
361 	au_writel(0, PSC_SEL(au1xpsc_i2s_workdata));
362 	au_sync();
363 	au_writel(au1xpsc_i2s_workdata->pm[0],
364 			PSC_SEL(au1xpsc_i2s_workdata));
365 	au_sync();
366 
367 	return 0;
368 }
369 
370 static struct snd_soc_dai_ops au1xpsc_i2s_dai_ops = {
371 	.trigger	= au1xpsc_i2s_trigger,
372 	.hw_params	= au1xpsc_i2s_hw_params,
373 	.set_fmt	= au1xpsc_i2s_set_fmt,
374 };
375 
376 struct snd_soc_dai au1xpsc_i2s_dai = {
377 	.name			= "au1xpsc_i2s",
378 	.probe			= au1xpsc_i2s_probe,
379 	.remove			= au1xpsc_i2s_remove,
380 	.suspend		= au1xpsc_i2s_suspend,
381 	.resume			= au1xpsc_i2s_resume,
382 	.playback = {
383 		.rates		= AU1XPSC_I2S_RATES,
384 		.formats	= AU1XPSC_I2S_FMTS,
385 		.channels_min	= 2,
386 		.channels_max	= 8,	/* 2 without external help */
387 	},
388 	.capture = {
389 		.rates		= AU1XPSC_I2S_RATES,
390 		.formats	= AU1XPSC_I2S_FMTS,
391 		.channels_min	= 2,
392 		.channels_max	= 8,	/* 2 without external help */
393 	},
394 	.ops = &au1xpsc_i2s_dai_ops,
395 };
396 EXPORT_SYMBOL(au1xpsc_i2s_dai);
397 
398 static int __init au1xpsc_i2s_init(void)
399 {
400 	au1xpsc_i2s_workdata = NULL;
401 	return snd_soc_register_dai(&au1xpsc_i2s_dai);
402 }
403 
404 static void __exit au1xpsc_i2s_exit(void)
405 {
406 	snd_soc_unregister_dai(&au1xpsc_i2s_dai);
407 }
408 
409 module_init(au1xpsc_i2s_init);
410 module_exit(au1xpsc_i2s_exit);
411 
412 MODULE_LICENSE("GPL");
413 MODULE_DESCRIPTION("Au12x0/Au1550 PSC I2S ALSA ASoC audio driver");
414 MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");
415