xref: /linux/sound/soc/au1x/psc-ac97.c (revision 0d456bad36d42d16022be045c8a53ddbb59ee478)
1 /*
2  * Au12x0/Au1550 PSC ALSA ASoC audio support.
3  *
4  * (c) 2007-2009 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 AC97 glue.
12  *
13  */
14 
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/slab.h>
18 #include <linux/device.h>
19 #include <linux/delay.h>
20 #include <linux/mutex.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 /* how often to retry failed codec register reads/writes */
32 #define AC97_RW_RETRIES	5
33 
34 #define AC97_DIR	\
35 	(SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
36 
37 #define AC97_RATES	\
38 	SNDRV_PCM_RATE_8000_48000
39 
40 #define AC97_FMTS	\
41 	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3BE)
42 
43 #define AC97PCR_START(stype)	\
44 	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TS : PSC_AC97PCR_RS)
45 #define AC97PCR_STOP(stype)	\
46 	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TP : PSC_AC97PCR_RP)
47 #define AC97PCR_CLRFIFO(stype)	\
48 	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TC : PSC_AC97PCR_RC)
49 
50 #define AC97STAT_BUSY(stype)	\
51 	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97STAT_TB : PSC_AC97STAT_RB)
52 
53 /* instance data. There can be only one, MacLeod!!!! */
54 static struct au1xpsc_audio_data *au1xpsc_ac97_workdata;
55 
56 #if 0
57 
58 /* this could theoretically work, but ac97->bus->card->private_data can be NULL
59  * when snd_ac97_mixer() is called; I don't know if the rest further down the
60  * chain are always valid either.
61  */
62 static inline struct au1xpsc_audio_data *ac97_to_pscdata(struct snd_ac97 *x)
63 {
64 	struct snd_soc_card *c = x->bus->card->private_data;
65 	return snd_soc_dai_get_drvdata(c->rtd->cpu_dai);
66 }
67 
68 #else
69 
70 #define ac97_to_pscdata(x)	au1xpsc_ac97_workdata
71 
72 #endif
73 
74 /* AC97 controller reads codec register */
75 static unsigned short au1xpsc_ac97_read(struct snd_ac97 *ac97,
76 					unsigned short reg)
77 {
78 	struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
79 	unsigned short retry, tmo;
80 	unsigned long data;
81 
82 	au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
83 	au_sync();
84 
85 	retry = AC97_RW_RETRIES;
86 	do {
87 		mutex_lock(&pscdata->lock);
88 
89 		au_writel(PSC_AC97CDC_RD | PSC_AC97CDC_INDX(reg),
90 			  AC97_CDC(pscdata));
91 		au_sync();
92 
93 		tmo = 20;
94 		do {
95 			udelay(21);
96 			if (au_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD)
97 				break;
98 		} while (--tmo);
99 
100 		data = au_readl(AC97_CDC(pscdata));
101 
102 		au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
103 		au_sync();
104 
105 		mutex_unlock(&pscdata->lock);
106 
107 		if (reg != ((data >> 16) & 0x7f))
108 			tmo = 1;	/* wrong register, try again */
109 
110 	} while (--retry && !tmo);
111 
112 	return retry ? data & 0xffff : 0xffff;
113 }
114 
115 /* AC97 controller writes to codec register */
116 static void au1xpsc_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
117 				unsigned short val)
118 {
119 	struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
120 	unsigned int tmo, retry;
121 
122 	au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
123 	au_sync();
124 
125 	retry = AC97_RW_RETRIES;
126 	do {
127 		mutex_lock(&pscdata->lock);
128 
129 		au_writel(PSC_AC97CDC_INDX(reg) | (val & 0xffff),
130 			  AC97_CDC(pscdata));
131 		au_sync();
132 
133 		tmo = 20;
134 		do {
135 			udelay(21);
136 			if (au_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD)
137 				break;
138 		} while (--tmo);
139 
140 		au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
141 		au_sync();
142 
143 		mutex_unlock(&pscdata->lock);
144 	} while (--retry && !tmo);
145 }
146 
147 /* AC97 controller asserts a warm reset */
148 static void au1xpsc_ac97_warm_reset(struct snd_ac97 *ac97)
149 {
150 	struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
151 
152 	au_writel(PSC_AC97RST_SNC, AC97_RST(pscdata));
153 	au_sync();
154 	msleep(10);
155 	au_writel(0, AC97_RST(pscdata));
156 	au_sync();
157 }
158 
159 static void au1xpsc_ac97_cold_reset(struct snd_ac97 *ac97)
160 {
161 	struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
162 	int i;
163 
164 	/* disable PSC during cold reset */
165 	au_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
166 	au_sync();
167 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(pscdata));
168 	au_sync();
169 
170 	/* issue cold reset */
171 	au_writel(PSC_AC97RST_RST, AC97_RST(pscdata));
172 	au_sync();
173 	msleep(500);
174 	au_writel(0, AC97_RST(pscdata));
175 	au_sync();
176 
177 	/* enable PSC */
178 	au_writel(PSC_CTRL_ENABLE, PSC_CTRL(pscdata));
179 	au_sync();
180 
181 	/* wait for PSC to indicate it's ready */
182 	i = 1000;
183 	while (!((au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_SR)) && (--i))
184 		msleep(1);
185 
186 	if (i == 0) {
187 		printk(KERN_ERR "au1xpsc-ac97: PSC not ready!\n");
188 		return;
189 	}
190 
191 	/* enable the ac97 function */
192 	au_writel(pscdata->cfg | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
193 	au_sync();
194 
195 	/* wait for AC97 core to become ready */
196 	i = 1000;
197 	while (!((au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)) && (--i))
198 		msleep(1);
199 	if (i == 0)
200 		printk(KERN_ERR "au1xpsc-ac97: AC97 ctrl not ready\n");
201 }
202 
203 /* AC97 controller operations */
204 struct snd_ac97_bus_ops soc_ac97_ops = {
205 	.read		= au1xpsc_ac97_read,
206 	.write		= au1xpsc_ac97_write,
207 	.reset		= au1xpsc_ac97_cold_reset,
208 	.warm_reset	= au1xpsc_ac97_warm_reset,
209 };
210 EXPORT_SYMBOL_GPL(soc_ac97_ops);
211 
212 static int au1xpsc_ac97_hw_params(struct snd_pcm_substream *substream,
213 				  struct snd_pcm_hw_params *params,
214 				  struct snd_soc_dai *dai)
215 {
216 	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
217 	unsigned long r, ro, stat;
218 	int chans, t, stype = substream->stream;
219 
220 	chans = params_channels(params);
221 
222 	r = ro = au_readl(AC97_CFG(pscdata));
223 	stat = au_readl(AC97_STAT(pscdata));
224 
225 	/* already active? */
226 	if (stat & (PSC_AC97STAT_TB | PSC_AC97STAT_RB)) {
227 		/* reject parameters not currently set up */
228 		if ((PSC_AC97CFG_GET_LEN(r) != params->msbits) ||
229 		    (pscdata->rate != params_rate(params)))
230 			return -EINVAL;
231 	} else {
232 
233 		/* set sample bitdepth: REG[24:21]=(BITS-2)/2 */
234 		r &= ~PSC_AC97CFG_LEN_MASK;
235 		r |= PSC_AC97CFG_SET_LEN(params->msbits);
236 
237 		/* channels: enable slots for front L/R channel */
238 		if (stype == SNDRV_PCM_STREAM_PLAYBACK) {
239 			r &= ~PSC_AC97CFG_TXSLOT_MASK;
240 			r |= PSC_AC97CFG_TXSLOT_ENA(3);
241 			r |= PSC_AC97CFG_TXSLOT_ENA(4);
242 		} else {
243 			r &= ~PSC_AC97CFG_RXSLOT_MASK;
244 			r |= PSC_AC97CFG_RXSLOT_ENA(3);
245 			r |= PSC_AC97CFG_RXSLOT_ENA(4);
246 		}
247 
248 		/* do we need to poke the hardware? */
249 		if (!(r ^ ro))
250 			goto out;
251 
252 		/* ac97 engine is about to be disabled */
253 		mutex_lock(&pscdata->lock);
254 
255 		/* disable AC97 device controller first... */
256 		au_writel(r & ~PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
257 		au_sync();
258 
259 		/* ...wait for it... */
260 		t = 100;
261 		while ((au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR) && --t)
262 			msleep(1);
263 
264 		if (!t)
265 			printk(KERN_ERR "PSC-AC97: can't disable!\n");
266 
267 		/* ...write config... */
268 		au_writel(r, AC97_CFG(pscdata));
269 		au_sync();
270 
271 		/* ...enable the AC97 controller again... */
272 		au_writel(r | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
273 		au_sync();
274 
275 		/* ...and wait for ready bit */
276 		t = 100;
277 		while ((!(au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)) && --t)
278 			msleep(1);
279 
280 		if (!t)
281 			printk(KERN_ERR "PSC-AC97: can't enable!\n");
282 
283 		mutex_unlock(&pscdata->lock);
284 
285 		pscdata->cfg = r;
286 		pscdata->rate = params_rate(params);
287 	}
288 
289 out:
290 	return 0;
291 }
292 
293 static int au1xpsc_ac97_trigger(struct snd_pcm_substream *substream,
294 				int cmd, struct snd_soc_dai *dai)
295 {
296 	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
297 	int ret, stype = substream->stream;
298 
299 	ret = 0;
300 
301 	switch (cmd) {
302 	case SNDRV_PCM_TRIGGER_START:
303 	case SNDRV_PCM_TRIGGER_RESUME:
304 		au_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
305 		au_sync();
306 		au_writel(AC97PCR_START(stype), AC97_PCR(pscdata));
307 		au_sync();
308 		break;
309 	case SNDRV_PCM_TRIGGER_STOP:
310 	case SNDRV_PCM_TRIGGER_SUSPEND:
311 		au_writel(AC97PCR_STOP(stype), AC97_PCR(pscdata));
312 		au_sync();
313 
314 		while (au_readl(AC97_STAT(pscdata)) & AC97STAT_BUSY(stype))
315 			asm volatile ("nop");
316 
317 		au_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
318 		au_sync();
319 
320 		break;
321 	default:
322 		ret = -EINVAL;
323 	}
324 	return ret;
325 }
326 
327 static int au1xpsc_ac97_startup(struct snd_pcm_substream *substream,
328 				struct snd_soc_dai *dai)
329 {
330 	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
331 	snd_soc_dai_set_dma_data(dai, substream, &pscdata->dmaids[0]);
332 	return 0;
333 }
334 
335 static int au1xpsc_ac97_probe(struct snd_soc_dai *dai)
336 {
337 	return au1xpsc_ac97_workdata ? 0 : -ENODEV;
338 }
339 
340 static const struct snd_soc_dai_ops au1xpsc_ac97_dai_ops = {
341 	.startup	= au1xpsc_ac97_startup,
342 	.trigger	= au1xpsc_ac97_trigger,
343 	.hw_params	= au1xpsc_ac97_hw_params,
344 };
345 
346 static const struct snd_soc_dai_driver au1xpsc_ac97_dai_template = {
347 	.ac97_control		= 1,
348 	.probe			= au1xpsc_ac97_probe,
349 	.playback = {
350 		.rates		= AC97_RATES,
351 		.formats	= AC97_FMTS,
352 		.channels_min	= 2,
353 		.channels_max	= 2,
354 	},
355 	.capture = {
356 		.rates		= AC97_RATES,
357 		.formats	= AC97_FMTS,
358 		.channels_min	= 2,
359 		.channels_max	= 2,
360 	},
361 	.ops = &au1xpsc_ac97_dai_ops,
362 };
363 
364 static int au1xpsc_ac97_drvprobe(struct platform_device *pdev)
365 {
366 	int ret;
367 	struct resource *iores, *dmares;
368 	unsigned long sel;
369 	struct au1xpsc_audio_data *wd;
370 
371 	wd = devm_kzalloc(&pdev->dev, sizeof(struct au1xpsc_audio_data),
372 			  GFP_KERNEL);
373 	if (!wd)
374 		return -ENOMEM;
375 
376 	mutex_init(&wd->lock);
377 
378 	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
379 	if (!iores)
380 		return -ENODEV;
381 
382 	if (!devm_request_mem_region(&pdev->dev, iores->start,
383 				     resource_size(iores),
384 				     pdev->name))
385 		return -EBUSY;
386 
387 	wd->mmio = devm_ioremap(&pdev->dev, iores->start,
388 				resource_size(iores));
389 	if (!wd->mmio)
390 		return -EBUSY;
391 
392 	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
393 	if (!dmares)
394 		return -EBUSY;
395 	wd->dmaids[SNDRV_PCM_STREAM_PLAYBACK] = dmares->start;
396 
397 	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 1);
398 	if (!dmares)
399 		return -EBUSY;
400 	wd->dmaids[SNDRV_PCM_STREAM_CAPTURE] = dmares->start;
401 
402 	/* configuration: max dma trigger threshold, enable ac97 */
403 	wd->cfg = PSC_AC97CFG_RT_FIFO8 | PSC_AC97CFG_TT_FIFO8 |
404 		  PSC_AC97CFG_DE_ENABLE;
405 
406 	/* preserve PSC clock source set up by platform	 */
407 	sel = au_readl(PSC_SEL(wd)) & PSC_SEL_CLK_MASK;
408 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
409 	au_sync();
410 	au_writel(0, PSC_SEL(wd));
411 	au_sync();
412 	au_writel(PSC_SEL_PS_AC97MODE | sel, PSC_SEL(wd));
413 	au_sync();
414 
415 	/* name the DAI like this device instance ("au1xpsc-ac97.PSCINDEX") */
416 	memcpy(&wd->dai_drv, &au1xpsc_ac97_dai_template,
417 	       sizeof(struct snd_soc_dai_driver));
418 	wd->dai_drv.name = dev_name(&pdev->dev);
419 
420 	platform_set_drvdata(pdev, wd);
421 
422 	ret = snd_soc_register_dai(&pdev->dev, &wd->dai_drv);
423 	if (ret)
424 		return ret;
425 
426 	au1xpsc_ac97_workdata = wd;
427 	return 0;
428 }
429 
430 static int au1xpsc_ac97_drvremove(struct platform_device *pdev)
431 {
432 	struct au1xpsc_audio_data *wd = platform_get_drvdata(pdev);
433 
434 	snd_soc_unregister_dai(&pdev->dev);
435 
436 	/* disable PSC completely */
437 	au_writel(0, AC97_CFG(wd));
438 	au_sync();
439 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
440 	au_sync();
441 
442 	au1xpsc_ac97_workdata = NULL;	/* MDEV */
443 
444 	return 0;
445 }
446 
447 #ifdef CONFIG_PM
448 static int au1xpsc_ac97_drvsuspend(struct device *dev)
449 {
450 	struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
451 
452 	/* save interesting registers and disable PSC */
453 	wd->pm[0] = au_readl(PSC_SEL(wd));
454 
455 	au_writel(0, AC97_CFG(wd));
456 	au_sync();
457 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
458 	au_sync();
459 
460 	return 0;
461 }
462 
463 static int au1xpsc_ac97_drvresume(struct device *dev)
464 {
465 	struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
466 
467 	/* restore PSC clock config */
468 	au_writel(wd->pm[0] | PSC_SEL_PS_AC97MODE, PSC_SEL(wd));
469 	au_sync();
470 
471 	/* after this point the ac97 core will cold-reset the codec.
472 	 * During cold-reset the PSC is reinitialized and the last
473 	 * configuration set up in hw_params() is restored.
474 	 */
475 	return 0;
476 }
477 
478 static struct dev_pm_ops au1xpscac97_pmops = {
479 	.suspend	= au1xpsc_ac97_drvsuspend,
480 	.resume		= au1xpsc_ac97_drvresume,
481 };
482 
483 #define AU1XPSCAC97_PMOPS &au1xpscac97_pmops
484 
485 #else
486 
487 #define AU1XPSCAC97_PMOPS NULL
488 
489 #endif
490 
491 static struct platform_driver au1xpsc_ac97_driver = {
492 	.driver	= {
493 		.name	= "au1xpsc_ac97",
494 		.owner	= THIS_MODULE,
495 		.pm	= AU1XPSCAC97_PMOPS,
496 	},
497 	.probe		= au1xpsc_ac97_drvprobe,
498 	.remove		= au1xpsc_ac97_drvremove,
499 };
500 
501 static int __init au1xpsc_ac97_load(void)
502 {
503 	au1xpsc_ac97_workdata = NULL;
504 	return platform_driver_register(&au1xpsc_ac97_driver);
505 }
506 
507 static void __exit au1xpsc_ac97_unload(void)
508 {
509 	platform_driver_unregister(&au1xpsc_ac97_driver);
510 }
511 
512 module_init(au1xpsc_ac97_load);
513 module_exit(au1xpsc_ac97_unload);
514 
515 MODULE_LICENSE("GPL");
516 MODULE_DESCRIPTION("Au12x0/Au1550 PSC AC97 ALSA ASoC audio driver");
517 MODULE_AUTHOR("Manuel Lauss");
518 
519