1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Au12x0/Au1550 PSC ALSA ASoC audio support.
4 *
5 * (c) 2007-2009 MSC Vertriebsges.m.b.H.,
6 *	Manuel Lauss <manuel.lauss@gmail.com>
7 *
8 * Au1xxx-PSC AC97 glue.
9 */
10
11#include <linux/init.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/device.h>
15#include <linux/delay.h>
16#include <linux/mutex.h>
17#include <linux/suspend.h>
18#include <sound/core.h>
19#include <sound/pcm.h>
20#include <sound/initval.h>
21#include <sound/soc.h>
22#include <asm/mach-au1x00/au1000.h>
23#include <asm/mach-au1x00/au1xxx_psc.h>
24
25#include "psc.h"
26
27/* how often to retry failed codec register reads/writes */
28#define AC97_RW_RETRIES	5
29
30#define AC97_DIR	\
31	(SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
32
33#define AC97_RATES	\
34	SNDRV_PCM_RATE_8000_48000
35
36#define AC97_FMTS	\
37	(SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S20_3BE)
38
39#define AC97PCR_START(stype)	\
40	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TS : PSC_AC97PCR_RS)
41#define AC97PCR_STOP(stype)	\
42	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TP : PSC_AC97PCR_RP)
43#define AC97PCR_CLRFIFO(stype)	\
44	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97PCR_TC : PSC_AC97PCR_RC)
45
46#define AC97STAT_BUSY(stype)	\
47	((stype) == SNDRV_PCM_STREAM_PLAYBACK ? PSC_AC97STAT_TB : PSC_AC97STAT_RB)
48
49/* instance data. There can be only one, MacLeod!!!! */
50static struct au1xpsc_audio_data *au1xpsc_ac97_workdata;
51
52#if 0
53
54/* this could theoretically work, but ac97->bus->card->private_data can be NULL
55 * when snd_ac97_mixer() is called; I don't know if the rest further down the
56 * chain are always valid either.
57 */
58static inline struct au1xpsc_audio_data *ac97_to_pscdata(struct snd_ac97 *x)
59{
60	struct snd_soc_card *c = x->bus->card->private_data;
61	return snd_soc_dai_get_drvdata(c->asoc_rtd_to_cpu(rtd, 0));
62}
63
64#else
65
66#define ac97_to_pscdata(x)	au1xpsc_ac97_workdata
67
68#endif
69
70/* AC97 controller reads codec register */
71static unsigned short au1xpsc_ac97_read(struct snd_ac97 *ac97,
72					unsigned short reg)
73{
74	struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
75	unsigned short retry, tmo;
76	unsigned long data;
77
78	__raw_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
79	wmb(); /* drain writebuffer */
80
81	retry = AC97_RW_RETRIES;
82	do {
83		mutex_lock(&pscdata->lock);
84
85		__raw_writel(PSC_AC97CDC_RD | PSC_AC97CDC_INDX(reg),
86			  AC97_CDC(pscdata));
87		wmb(); /* drain writebuffer */
88
89		tmo = 20;
90		do {
91			udelay(21);
92			if (__raw_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD)
93				break;
94		} while (--tmo);
95
96		data = __raw_readl(AC97_CDC(pscdata));
97
98		__raw_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
99		wmb(); /* drain writebuffer */
100
101		mutex_unlock(&pscdata->lock);
102
103		if (reg != ((data >> 16) & 0x7f))
104			tmo = 1;	/* wrong register, try again */
105
106	} while (--retry && !tmo);
107
108	return retry ? data & 0xffff : 0xffff;
109}
110
111/* AC97 controller writes to codec register */
112static void au1xpsc_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
113				unsigned short val)
114{
115	struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
116	unsigned int tmo, retry;
117
118	__raw_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
119	wmb(); /* drain writebuffer */
120
121	retry = AC97_RW_RETRIES;
122	do {
123		mutex_lock(&pscdata->lock);
124
125		__raw_writel(PSC_AC97CDC_INDX(reg) | (val & 0xffff),
126			  AC97_CDC(pscdata));
127		wmb(); /* drain writebuffer */
128
129		tmo = 20;
130		do {
131			udelay(21);
132			if (__raw_readl(AC97_EVNT(pscdata)) & PSC_AC97EVNT_CD)
133				break;
134		} while (--tmo);
135
136		__raw_writel(PSC_AC97EVNT_CD, AC97_EVNT(pscdata));
137		wmb(); /* drain writebuffer */
138
139		mutex_unlock(&pscdata->lock);
140	} while (--retry && !tmo);
141}
142
143/* AC97 controller asserts a warm reset */
144static void au1xpsc_ac97_warm_reset(struct snd_ac97 *ac97)
145{
146	struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
147
148	__raw_writel(PSC_AC97RST_SNC, AC97_RST(pscdata));
149	wmb(); /* drain writebuffer */
150	msleep(10);
151	__raw_writel(0, AC97_RST(pscdata));
152	wmb(); /* drain writebuffer */
153}
154
155static void au1xpsc_ac97_cold_reset(struct snd_ac97 *ac97)
156{
157	struct au1xpsc_audio_data *pscdata = ac97_to_pscdata(ac97);
158	int i;
159
160	/* disable PSC during cold reset */
161	__raw_writel(0, AC97_CFG(au1xpsc_ac97_workdata));
162	wmb(); /* drain writebuffer */
163	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(pscdata));
164	wmb(); /* drain writebuffer */
165
166	/* issue cold reset */
167	__raw_writel(PSC_AC97RST_RST, AC97_RST(pscdata));
168	wmb(); /* drain writebuffer */
169	msleep(500);
170	__raw_writel(0, AC97_RST(pscdata));
171	wmb(); /* drain writebuffer */
172
173	/* enable PSC */
174	__raw_writel(PSC_CTRL_ENABLE, PSC_CTRL(pscdata));
175	wmb(); /* drain writebuffer */
176
177	/* wait for PSC to indicate it's ready */
178	i = 1000;
179	while (!((__raw_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_SR)) && (--i))
180		msleep(1);
181
182	if (i == 0) {
183		printk(KERN_ERR "au1xpsc-ac97: PSC not ready!\n");
184		return;
185	}
186
187	/* enable the ac97 function */
188	__raw_writel(pscdata->cfg | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
189	wmb(); /* drain writebuffer */
190
191	/* wait for AC97 core to become ready */
192	i = 1000;
193	while (!((__raw_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)) && (--i))
194		msleep(1);
195	if (i == 0)
196		printk(KERN_ERR "au1xpsc-ac97: AC97 ctrl not ready\n");
197}
198
199/* AC97 controller operations */
200static struct snd_ac97_bus_ops psc_ac97_ops = {
201	.read		= au1xpsc_ac97_read,
202	.write		= au1xpsc_ac97_write,
203	.reset		= au1xpsc_ac97_cold_reset,
204	.warm_reset	= au1xpsc_ac97_warm_reset,
205};
206
207static int au1xpsc_ac97_hw_params(struct snd_pcm_substream *substream,
208				  struct snd_pcm_hw_params *params,
209				  struct snd_soc_dai *dai)
210{
211	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
212	unsigned long r, ro, stat;
213	int chans, t, stype = substream->stream;
214
215	chans = params_channels(params);
216
217	r = ro = __raw_readl(AC97_CFG(pscdata));
218	stat = __raw_readl(AC97_STAT(pscdata));
219
220	/* already active? */
221	if (stat & (PSC_AC97STAT_TB | PSC_AC97STAT_RB)) {
222		/* reject parameters not currently set up */
223		if ((PSC_AC97CFG_GET_LEN(r) != params->msbits) ||
224		    (pscdata->rate != params_rate(params)))
225			return -EINVAL;
226	} else {
227
228		/* set sample bitdepth: REG[24:21]=(BITS-2)/2 */
229		r &= ~PSC_AC97CFG_LEN_MASK;
230		r |= PSC_AC97CFG_SET_LEN(params->msbits);
231
232		/* channels: enable slots for front L/R channel */
233		if (stype == SNDRV_PCM_STREAM_PLAYBACK) {
234			r &= ~PSC_AC97CFG_TXSLOT_MASK;
235			r |= PSC_AC97CFG_TXSLOT_ENA(3);
236			r |= PSC_AC97CFG_TXSLOT_ENA(4);
237		} else {
238			r &= ~PSC_AC97CFG_RXSLOT_MASK;
239			r |= PSC_AC97CFG_RXSLOT_ENA(3);
240			r |= PSC_AC97CFG_RXSLOT_ENA(4);
241		}
242
243		/* do we need to poke the hardware? */
244		if (!(r ^ ro))
245			goto out;
246
247		/* ac97 engine is about to be disabled */
248		mutex_lock(&pscdata->lock);
249
250		/* disable AC97 device controller first... */
251		__raw_writel(r & ~PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
252		wmb(); /* drain writebuffer */
253
254		/* ...wait for it... */
255		t = 100;
256		while ((__raw_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR) && --t)
257			msleep(1);
258
259		if (!t)
260			printk(KERN_ERR "PSC-AC97: can't disable!\n");
261
262		/* ...write config... */
263		__raw_writel(r, AC97_CFG(pscdata));
264		wmb(); /* drain writebuffer */
265
266		/* ...enable the AC97 controller again... */
267		__raw_writel(r | PSC_AC97CFG_DE_ENABLE, AC97_CFG(pscdata));
268		wmb(); /* drain writebuffer */
269
270		/* ...and wait for ready bit */
271		t = 100;
272		while ((!(__raw_readl(AC97_STAT(pscdata)) & PSC_AC97STAT_DR)) && --t)
273			msleep(1);
274
275		if (!t)
276			printk(KERN_ERR "PSC-AC97: can't enable!\n");
277
278		mutex_unlock(&pscdata->lock);
279
280		pscdata->cfg = r;
281		pscdata->rate = params_rate(params);
282	}
283
284out:
285	return 0;
286}
287
288static int au1xpsc_ac97_trigger(struct snd_pcm_substream *substream,
289				int cmd, struct snd_soc_dai *dai)
290{
291	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
292	int ret, stype = substream->stream;
293
294	ret = 0;
295
296	switch (cmd) {
297	case SNDRV_PCM_TRIGGER_START:
298	case SNDRV_PCM_TRIGGER_RESUME:
299		__raw_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
300		wmb(); /* drain writebuffer */
301		__raw_writel(AC97PCR_START(stype), AC97_PCR(pscdata));
302		wmb(); /* drain writebuffer */
303		break;
304	case SNDRV_PCM_TRIGGER_STOP:
305	case SNDRV_PCM_TRIGGER_SUSPEND:
306		__raw_writel(AC97PCR_STOP(stype), AC97_PCR(pscdata));
307		wmb(); /* drain writebuffer */
308
309		while (__raw_readl(AC97_STAT(pscdata)) & AC97STAT_BUSY(stype))
310			asm volatile ("nop");
311
312		__raw_writel(AC97PCR_CLRFIFO(stype), AC97_PCR(pscdata));
313		wmb(); /* drain writebuffer */
314
315		break;
316	default:
317		ret = -EINVAL;
318	}
319	return ret;
320}
321
322static int au1xpsc_ac97_startup(struct snd_pcm_substream *substream,
323				struct snd_soc_dai *dai)
324{
325	struct au1xpsc_audio_data *pscdata = snd_soc_dai_get_drvdata(dai);
326	snd_soc_dai_set_dma_data(dai, substream, &pscdata->dmaids[0]);
327	return 0;
328}
329
330static int au1xpsc_ac97_probe(struct snd_soc_dai *dai)
331{
332	return au1xpsc_ac97_workdata ? 0 : -ENODEV;
333}
334
335static const struct snd_soc_dai_ops au1xpsc_ac97_dai_ops = {
336	.startup	= au1xpsc_ac97_startup,
337	.trigger	= au1xpsc_ac97_trigger,
338	.hw_params	= au1xpsc_ac97_hw_params,
339};
340
341static const struct snd_soc_dai_driver au1xpsc_ac97_dai_template = {
342	.probe			= au1xpsc_ac97_probe,
343	.playback = {
344		.rates		= AC97_RATES,
345		.formats	= AC97_FMTS,
346		.channels_min	= 2,
347		.channels_max	= 2,
348	},
349	.capture = {
350		.rates		= AC97_RATES,
351		.formats	= AC97_FMTS,
352		.channels_min	= 2,
353		.channels_max	= 2,
354	},
355	.ops = &au1xpsc_ac97_dai_ops,
356};
357
358static const struct snd_soc_component_driver au1xpsc_ac97_component = {
359	.name		= "au1xpsc-ac97",
360};
361
362static int au1xpsc_ac97_drvprobe(struct platform_device *pdev)
363{
364	int ret;
365	struct resource *dmares;
366	unsigned long sel;
367	struct au1xpsc_audio_data *wd;
368
369	wd = devm_kzalloc(&pdev->dev, sizeof(struct au1xpsc_audio_data),
370			  GFP_KERNEL);
371	if (!wd)
372		return -ENOMEM;
373
374	mutex_init(&wd->lock);
375
376	wd->mmio = devm_platform_ioremap_resource(pdev, 0);
377	if (IS_ERR(wd->mmio))
378		return PTR_ERR(wd->mmio);
379
380	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
381	if (!dmares)
382		return -EBUSY;
383	wd->dmaids[SNDRV_PCM_STREAM_PLAYBACK] = dmares->start;
384
385	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 1);
386	if (!dmares)
387		return -EBUSY;
388	wd->dmaids[SNDRV_PCM_STREAM_CAPTURE] = dmares->start;
389
390	/* configuration: max dma trigger threshold, enable ac97 */
391	wd->cfg = PSC_AC97CFG_RT_FIFO8 | PSC_AC97CFG_TT_FIFO8 |
392		  PSC_AC97CFG_DE_ENABLE;
393
394	/* preserve PSC clock source set up by platform	 */
395	sel = __raw_readl(PSC_SEL(wd)) & PSC_SEL_CLK_MASK;
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(PSC_SEL_PS_AC97MODE | sel, PSC_SEL(wd));
401	wmb(); /* drain writebuffer */
402
403	/* name the DAI like this device instance ("au1xpsc-ac97.PSCINDEX") */
404	memcpy(&wd->dai_drv, &au1xpsc_ac97_dai_template,
405	       sizeof(struct snd_soc_dai_driver));
406	wd->dai_drv.name = dev_name(&pdev->dev);
407
408	platform_set_drvdata(pdev, wd);
409
410	ret = snd_soc_set_ac97_ops(&psc_ac97_ops);
411	if (ret)
412		return ret;
413
414	ret = snd_soc_register_component(&pdev->dev, &au1xpsc_ac97_component,
415					 &wd->dai_drv, 1);
416	if (ret)
417		return ret;
418
419	au1xpsc_ac97_workdata = wd;
420	return 0;
421}
422
423static int au1xpsc_ac97_drvremove(struct platform_device *pdev)
424{
425	struct au1xpsc_audio_data *wd = platform_get_drvdata(pdev);
426
427	snd_soc_unregister_component(&pdev->dev);
428
429	/* disable PSC completely */
430	__raw_writel(0, AC97_CFG(wd));
431	wmb(); /* drain writebuffer */
432	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
433	wmb(); /* drain writebuffer */
434
435	au1xpsc_ac97_workdata = NULL;	/* MDEV */
436
437	return 0;
438}
439
440#ifdef CONFIG_PM
441static int au1xpsc_ac97_drvsuspend(struct device *dev)
442{
443	struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
444
445	/* save interesting registers and disable PSC */
446	wd->pm[0] = __raw_readl(PSC_SEL(wd));
447
448	__raw_writel(0, AC97_CFG(wd));
449	wmb(); /* drain writebuffer */
450	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
451	wmb(); /* drain writebuffer */
452
453	return 0;
454}
455
456static int au1xpsc_ac97_drvresume(struct device *dev)
457{
458	struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
459
460	/* restore PSC clock config */
461	__raw_writel(wd->pm[0] | PSC_SEL_PS_AC97MODE, PSC_SEL(wd));
462	wmb(); /* drain writebuffer */
463
464	/* after this point the ac97 core will cold-reset the codec.
465	 * During cold-reset the PSC is reinitialized and the last
466	 * configuration set up in hw_params() is restored.
467	 */
468	return 0;
469}
470
471static const struct dev_pm_ops au1xpscac97_pmops = {
472	.suspend	= au1xpsc_ac97_drvsuspend,
473	.resume		= au1xpsc_ac97_drvresume,
474};
475
476#define AU1XPSCAC97_PMOPS &au1xpscac97_pmops
477
478#else
479
480#define AU1XPSCAC97_PMOPS NULL
481
482#endif
483
484static struct platform_driver au1xpsc_ac97_driver = {
485	.driver	= {
486		.name	= "au1xpsc_ac97",
487		.pm	= AU1XPSCAC97_PMOPS,
488	},
489	.probe		= au1xpsc_ac97_drvprobe,
490	.remove		= au1xpsc_ac97_drvremove,
491};
492
493module_platform_driver(au1xpsc_ac97_driver);
494
495MODULE_LICENSE("GPL");
496MODULE_DESCRIPTION("Au12x0/Au1550 PSC AC97 ALSA ASoC audio driver");
497MODULE_AUTHOR("Manuel Lauss");
498
499