xref: /openbmc/linux/sound/soc/au1x/psc-ac97.c (revision fd589a8f)
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  * 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  */
17 
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/device.h>
21 #include <linux/delay.h>
22 #include <linux/mutex.h>
23 #include <linux/suspend.h>
24 #include <sound/core.h>
25 #include <sound/pcm.h>
26 #include <sound/initval.h>
27 #include <sound/soc.h>
28 #include <asm/mach-au1x00/au1000.h>
29 #include <asm/mach-au1x00/au1xxx_psc.h>
30 
31 #include "psc.h"
32 
33 /* how often to retry failed codec register reads/writes */
34 #define AC97_RW_RETRIES	5
35 
36 #define AC97_DIR	\
37 	(SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
38 
39 #define AC97_RATES	\
40 	SNDRV_PCM_RATE_8000_48000
41 
42 #define AC97_FMTS	\
43 	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3BE)
44 
45 #define AC97PCR_START(stype)	\
46 	((stype) == PCM_TX ? PSC_AC97PCR_TS : PSC_AC97PCR_RS)
47 #define AC97PCR_STOP(stype)	\
48 	((stype) == PCM_TX ? PSC_AC97PCR_TP : PSC_AC97PCR_RP)
49 #define AC97PCR_CLRFIFO(stype)	\
50 	((stype) == PCM_TX ? PSC_AC97PCR_TC : PSC_AC97PCR_RC)
51 
52 #define AC97STAT_BUSY(stype)	\
53 	((stype) == PCM_TX ? PSC_AC97STAT_TB : PSC_AC97STAT_RB)
54 
55 /* instance data. There can be only one, MacLeod!!!! */
56 static struct au1xpsc_audio_data *au1xpsc_ac97_workdata;
57 
58 /* AC97 controller reads codec register */
59 static unsigned short au1xpsc_ac97_read(struct snd_ac97 *ac97,
60 					unsigned short reg)
61 {
62 	/* FIXME */
63 	struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
64 	unsigned short data, retry, tmo;
65 
66 	au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
67 	au_sync();
68 
69 	retry = AC97_RW_RETRIES;
70 	do {
71 		mutex_lock(&pscdata->lock);
72 
73 		au_writel(PSC_AC97CDC_RD | PSC_AC97CDC_INDX(reg),
74 			  AC97_CDC(pscdata));
75 		au_sync();
76 
77 		tmo = 2000;
78 		while ((!(au_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD))
79 			&& --tmo)
80 			udelay(2);
81 
82 		data = au_readl(AC97_CDC(pscdata)) & 0xffff;
83 
84 		au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
85 		au_sync();
86 
87 		mutex_unlock(&pscdata->lock);
88 	} while (--retry && !tmo);
89 
90 	return retry ? data : 0xffff;
91 }
92 
93 /* AC97 controller writes to codec register */
94 static void au1xpsc_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
95 				unsigned short val)
96 {
97 	/* FIXME */
98 	struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
99 	unsigned int tmo, retry;
100 
101 	au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
102 	au_sync();
103 
104 	retry = AC97_RW_RETRIES;
105 	do {
106 		mutex_lock(&pscdata->lock);
107 
108 		au_writel(PSC_AC97CDC_INDX(reg) | (val & 0xffff),
109 			  AC97_CDC(pscdata));
110 		au_sync();
111 
112 		tmo = 2000;
113 		while ((!(au_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD))
114 		       && --tmo)
115 			udelay(2);
116 
117 		au_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
118 		au_sync();
119 
120 		mutex_unlock(&pscdata->lock);
121 	} while (--retry && !tmo);
122 }
123 
124 /* AC97 controller asserts a warm reset */
125 static void au1xpsc_ac97_warm_reset(struct snd_ac97 *ac97)
126 {
127 	/* FIXME */
128 	struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
129 
130 	au_writel(PSC_AC97RST_SNC, AC97_RST(pscdata));
131 	au_sync();
132 	msleep(10);
133 	au_writel(0, AC97_RST(pscdata));
134 	au_sync();
135 }
136 
137 static void au1xpsc_ac97_cold_reset(struct snd_ac97 *ac97)
138 {
139 	/* FIXME */
140 	struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
141 	int i;
142 
143 	/* disable PSC during cold reset */
144 	au_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
145 	au_sync();
146 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(pscdata));
147 	au_sync();
148 
149 	/* issue cold reset */
150 	au_writel(PSC_AC97RST_RST, AC97_RST(pscdata));
151 	au_sync();
152 	msleep(500);
153 	au_writel(0, AC97_RST(pscdata));
154 	au_sync();
155 
156 	/* enable PSC */
157 	au_writel(PSC_CTRL_ENABLE, PSC_CTRL(pscdata));
158 	au_sync();
159 
160 	/* wait for PSC to indicate it's ready */
161 	i = 1000;
162 	while (!((au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_SR)) && (--i))
163 		msleep(1);
164 
165 	if (i == 0) {
166 		printk(KERN_ERR "au1xpsc-ac97: PSC not ready!\n");
167 		return;
168 	}
169 
170 	/* enable the ac97 function */
171 	au_writel(pscdata->cfg | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
172 	au_sync();
173 
174 	/* wait for AC97 core to become ready */
175 	i = 1000;
176 	while (!((au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)) && (--i))
177 		msleep(1);
178 	if (i == 0)
179 		printk(KERN_ERR "au1xpsc-ac97: AC97 ctrl not ready\n");
180 }
181 
182 /* AC97 controller operations */
183 struct snd_ac97_bus_ops soc_ac97_ops = {
184 	.read		= au1xpsc_ac97_read,
185 	.write		= au1xpsc_ac97_write,
186 	.reset		= au1xpsc_ac97_cold_reset,
187 	.warm_reset	= au1xpsc_ac97_warm_reset,
188 };
189 EXPORT_SYMBOL_GPL(soc_ac97_ops);
190 
191 static int au1xpsc_ac97_hw_params(struct snd_pcm_substream *substream,
192 				  struct snd_pcm_hw_params *params,
193 				  struct snd_soc_dai *dai)
194 {
195 	/* FIXME */
196 	struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
197 	unsigned long r, ro, stat;
198 	int chans, stype = SUBSTREAM_TYPE(substream);
199 
200 	chans = params_channels(params);
201 
202 	r = ro = au_readl(AC97_CFG(pscdata));
203 	stat = au_readl(AC97_STAT(pscdata));
204 
205 	/* already active? */
206 	if (stat & (PSC_AC97STAT_TB | PSC_AC97STAT_RB)) {
207 		/* reject parameters not currently set up */
208 		if ((PSC_AC97CFG_GET_LEN(r) != params->msbits) ||
209 		    (pscdata->rate != params_rate(params)))
210 			return -EINVAL;
211 	} else {
212 
213 		/* set sample bitdepth: REG[24:21]=(BITS-2)/2 */
214 		r &= ~PSC_AC97CFG_LEN_MASK;
215 		r |= PSC_AC97CFG_SET_LEN(params->msbits);
216 
217 		/* channels: enable slots for front L/R channel */
218 		if (stype == PCM_TX) {
219 			r &= ~PSC_AC97CFG_TXSLOT_MASK;
220 			r |= PSC_AC97CFG_TXSLOT_ENA(3);
221 			r |= PSC_AC97CFG_TXSLOT_ENA(4);
222 		} else {
223 			r &= ~PSC_AC97CFG_RXSLOT_MASK;
224 			r |= PSC_AC97CFG_RXSLOT_ENA(3);
225 			r |= PSC_AC97CFG_RXSLOT_ENA(4);
226 		}
227 
228 		/* do we need to poke the hardware? */
229 		if (!(r ^ ro))
230 			goto out;
231 
232 		/* ac97 engine is about to be disabled */
233 		mutex_lock(&pscdata->lock);
234 
235 		/* disable AC97 device controller first... */
236 		au_writel(r & ~PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
237 		au_sync();
238 
239 		/* ...wait for it... */
240 		while (au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)
241 			asm volatile ("nop");
242 
243 		/* ...write config... */
244 		au_writel(r, AC97_CFG(pscdata));
245 		au_sync();
246 
247 		/* ...enable the AC97 controller again... */
248 		au_writel(r | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
249 		au_sync();
250 
251 		/* ...and wait for ready bit */
252 		while (!(au_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR))
253 			asm volatile ("nop");
254 
255 		mutex_unlock(&pscdata->lock);
256 
257 		pscdata->cfg = r;
258 		pscdata->rate = params_rate(params);
259 	}
260 
261 out:
262 	return 0;
263 }
264 
265 static int au1xpsc_ac97_trigger(struct snd_pcm_substream *substream,
266 				int cmd, struct snd_soc_dai *dai)
267 {
268 	/* FIXME */
269 	struct au1xpsc_audio_data *pscdata = au1xpsc_ac97_workdata;
270 	int ret, stype = SUBSTREAM_TYPE(substream);
271 
272 	ret = 0;
273 
274 	switch (cmd) {
275 	case SNDRV_PCM_TRIGGER_START:
276 	case SNDRV_PCM_TRIGGER_RESUME:
277 		au_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
278 		au_sync();
279 		au_writel(AC97PCR_START(stype), AC97_PCR(pscdata));
280 		au_sync();
281 		break;
282 	case SNDRV_PCM_TRIGGER_STOP:
283 	case SNDRV_PCM_TRIGGER_SUSPEND:
284 		au_writel(AC97PCR_STOP(stype), AC97_PCR(pscdata));
285 		au_sync();
286 
287 		while (au_readl(AC97_STAT(pscdata)) & AC97STAT_BUSY(stype))
288 			asm volatile ("nop");
289 
290 		au_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
291 		au_sync();
292 
293 		break;
294 	default:
295 		ret = -EINVAL;
296 	}
297 	return ret;
298 }
299 
300 static int au1xpsc_ac97_probe(struct platform_device *pdev,
301 			      struct snd_soc_dai *dai)
302 {
303 	int ret;
304 	struct resource *r;
305 	unsigned long sel;
306 
307 	if (au1xpsc_ac97_workdata)
308 		return -EBUSY;
309 
310 	au1xpsc_ac97_workdata =
311 		kzalloc(sizeof(struct au1xpsc_audio_data), GFP_KERNEL);
312 	if (!au1xpsc_ac97_workdata)
313 		return -ENOMEM;
314 
315 	mutex_init(&au1xpsc_ac97_workdata->lock);
316 
317 	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
318 	if (!r) {
319 		ret = -ENODEV;
320 		goto out0;
321 	}
322 
323 	ret = -EBUSY;
324 	au1xpsc_ac97_workdata->ioarea =
325 		request_mem_region(r->start, r->end - r->start + 1,
326 					"au1xpsc_ac97");
327 	if (!au1xpsc_ac97_workdata->ioarea)
328 		goto out0;
329 
330 	au1xpsc_ac97_workdata->mmio = ioremap(r->start, 0xffff);
331 	if (!au1xpsc_ac97_workdata->mmio)
332 		goto out1;
333 
334 	/* configuration: max dma trigger threshold, enable ac97 */
335 	au1xpsc_ac97_workdata->cfg = PSC_AC97CFG_RT_FIFO8 |
336 				     PSC_AC97CFG_TT_FIFO8 |
337 				     PSC_AC97CFG_DE_ENABLE;
338 
339 	/* preserve PSC clock source set up by platform (dev.platform_data
340 	 * is already occupied by soc layer)
341 	 */
342 	sel = au_readl(PSC_SEL(au1xpsc_ac97_workdata)) & PSC_SEL_CLK_MASK;
343 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_ac97_workdata));
344 	au_sync();
345 	au_writel(0, PSC_SEL(au1xpsc_ac97_workdata));
346 	au_sync();
347 	au_writel(PSC_SEL_PS_AC97MODE | sel, PSC_SEL(au1xpsc_ac97_workdata));
348 	au_sync();
349 	/* next up: cold reset.  Dont check for PSC-ready now since
350 	 * there may not be any codec clock yet.
351 	 */
352 
353 	return 0;
354 
355 out1:
356 	release_resource(au1xpsc_ac97_workdata->ioarea);
357 	kfree(au1xpsc_ac97_workdata->ioarea);
358 out0:
359 	kfree(au1xpsc_ac97_workdata);
360 	au1xpsc_ac97_workdata = NULL;
361 	return ret;
362 }
363 
364 static void au1xpsc_ac97_remove(struct platform_device *pdev,
365 				struct snd_soc_dai *dai)
366 {
367 	/* disable PSC completely */
368 	au_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
369 	au_sync();
370 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_ac97_workdata));
371 	au_sync();
372 
373 	iounmap(au1xpsc_ac97_workdata->mmio);
374 	release_resource(au1xpsc_ac97_workdata->ioarea);
375 	kfree(au1xpsc_ac97_workdata->ioarea);
376 	kfree(au1xpsc_ac97_workdata);
377 	au1xpsc_ac97_workdata = NULL;
378 }
379 
380 static int au1xpsc_ac97_suspend(struct snd_soc_dai *dai)
381 {
382 	/* save interesting registers and disable PSC */
383 	au1xpsc_ac97_workdata->pm[0] =
384 			au_readl(PSC_SEL(au1xpsc_ac97_workdata));
385 
386 	au_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
387 	au_sync();
388 	au_writel(PSC_CTRL_DISABLE, PSC_CTRL(au1xpsc_ac97_workdata));
389 	au_sync();
390 
391 	return 0;
392 }
393 
394 static int au1xpsc_ac97_resume(struct snd_soc_dai *dai)
395 {
396 	/* restore PSC clock config */
397 	au_writel(au1xpsc_ac97_workdata->pm[0] | PSC_SEL_PS_AC97MODE,
398 			PSC_SEL(au1xpsc_ac97_workdata));
399 	au_sync();
400 
401 	/* after this point the ac97 core will cold-reset the codec.
402 	 * During cold-reset the PSC is reinitialized and the last
403 	 * configuration set up in hw_params() is restored.
404 	 */
405 	return 0;
406 }
407 
408 static struct snd_soc_dai_ops au1xpsc_ac97_dai_ops = {
409 	.trigger	= au1xpsc_ac97_trigger,
410 	.hw_params	= au1xpsc_ac97_hw_params,
411 };
412 
413 struct snd_soc_dai au1xpsc_ac97_dai = {
414 	.name			= "au1xpsc_ac97",
415 	.ac97_control		= 1,
416 	.probe			= au1xpsc_ac97_probe,
417 	.remove			= au1xpsc_ac97_remove,
418 	.suspend		= au1xpsc_ac97_suspend,
419 	.resume			= au1xpsc_ac97_resume,
420 	.playback = {
421 		.rates		= AC97_RATES,
422 		.formats	= AC97_FMTS,
423 		.channels_min	= 2,
424 		.channels_max	= 2,
425 	},
426 	.capture = {
427 		.rates		= AC97_RATES,
428 		.formats	= AC97_FMTS,
429 		.channels_min	= 2,
430 		.channels_max	= 2,
431 	},
432 	.ops = &au1xpsc_ac97_dai_ops,
433 };
434 EXPORT_SYMBOL_GPL(au1xpsc_ac97_dai);
435 
436 static int __init au1xpsc_ac97_init(void)
437 {
438 	au1xpsc_ac97_workdata = NULL;
439 	return snd_soc_register_dai(&au1xpsc_ac97_dai);
440 }
441 
442 static void __exit au1xpsc_ac97_exit(void)
443 {
444 	snd_soc_unregister_dai(&au1xpsc_ac97_dai);
445 }
446 
447 module_init(au1xpsc_ac97_init);
448 module_exit(au1xpsc_ac97_exit);
449 
450 MODULE_LICENSE("GPL");
451 MODULE_DESCRIPTION("Au12x0/Au1550 PSC AC97 ALSA ASoC audio driver");
452 MODULE_AUTHOR("Manuel Lauss <manuel.lauss@gmail.com>");
453