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
54static 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;
109out:
110	return ret;
111}
112
113static 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 */
147static 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
175psc_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
182static 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	}
212out:
213	return ret;
214}
215
216static 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
239static 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
260static 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
268static 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
275static 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
291static const struct snd_soc_component_driver au1xpsc_i2s_component = {
292	.name		= "au1xpsc-i2s",
293};
294
295static int au1xpsc_i2s_drvprobe(struct platform_device *pdev)
296{
297	struct resource *iores, *dmares;
298	unsigned long sel;
299	struct au1xpsc_audio_data *wd;
300
301	wd = devm_kzalloc(&pdev->dev, sizeof(struct au1xpsc_audio_data),
302			  GFP_KERNEL);
303	if (!wd)
304		return -ENOMEM;
305
306	iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
307	wd->mmio = devm_ioremap_resource(&pdev->dev, iores);
308	if (IS_ERR(wd->mmio))
309		return PTR_ERR(wd->mmio);
310
311	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
312	if (!dmares)
313		return -EBUSY;
314	wd->dmaids[SNDRV_PCM_STREAM_PLAYBACK] = dmares->start;
315
316	dmares = platform_get_resource(pdev, IORESOURCE_DMA, 1);
317	if (!dmares)
318		return -EBUSY;
319	wd->dmaids[SNDRV_PCM_STREAM_CAPTURE] = dmares->start;
320
321	/* preserve PSC clock source set up by platform (dev.platform_data
322	 * is already occupied by soc layer)
323	 */
324	sel = __raw_readl(PSC_SEL(wd)) & PSC_SEL_CLK_MASK;
325	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
326	wmb(); /* drain writebuffer */
327	__raw_writel(PSC_SEL_PS_I2SMODE | sel, PSC_SEL(wd));
328	__raw_writel(0, I2S_CFG(wd));
329	wmb(); /* drain writebuffer */
330
331	/* preconfigure: set max rx/tx fifo depths */
332	wd->cfg |= PSC_I2SCFG_RT_FIFO8 | PSC_I2SCFG_TT_FIFO8;
333
334	/* don't wait for I2S core to become ready now; clocks may not
335	 * be running yet; depending on clock input for PSC a wait might
336	 * time out.
337	 */
338
339	/* name the DAI like this device instance ("au1xpsc-i2s.PSCINDEX") */
340	memcpy(&wd->dai_drv, &au1xpsc_i2s_dai_template,
341	       sizeof(struct snd_soc_dai_driver));
342	wd->dai_drv.name = dev_name(&pdev->dev);
343
344	platform_set_drvdata(pdev, wd);
345
346	return snd_soc_register_component(&pdev->dev, &au1xpsc_i2s_component,
347					  &wd->dai_drv, 1);
348}
349
350static int au1xpsc_i2s_drvremove(struct platform_device *pdev)
351{
352	struct au1xpsc_audio_data *wd = platform_get_drvdata(pdev);
353
354	snd_soc_unregister_component(&pdev->dev);
355
356	__raw_writel(0, I2S_CFG(wd));
357	wmb(); /* drain writebuffer */
358	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
359	wmb(); /* drain writebuffer */
360
361	return 0;
362}
363
364#ifdef CONFIG_PM
365static int au1xpsc_i2s_drvsuspend(struct device *dev)
366{
367	struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
368
369	/* save interesting register and disable PSC */
370	wd->pm[0] = __raw_readl(PSC_SEL(wd));
371
372	__raw_writel(0, I2S_CFG(wd));
373	wmb(); /* drain writebuffer */
374	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
375	wmb(); /* drain writebuffer */
376
377	return 0;
378}
379
380static int au1xpsc_i2s_drvresume(struct device *dev)
381{
382	struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
383
384	/* select I2S mode and PSC clock */
385	__raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
386	wmb(); /* drain writebuffer */
387	__raw_writel(0, PSC_SEL(wd));
388	wmb(); /* drain writebuffer */
389	__raw_writel(wd->pm[0], PSC_SEL(wd));
390	wmb(); /* drain writebuffer */
391
392	return 0;
393}
394
395static struct dev_pm_ops au1xpsci2s_pmops = {
396	.suspend	= au1xpsc_i2s_drvsuspend,
397	.resume		= au1xpsc_i2s_drvresume,
398};
399
400#define AU1XPSCI2S_PMOPS &au1xpsci2s_pmops
401
402#else
403
404#define AU1XPSCI2S_PMOPS NULL
405
406#endif
407
408static struct platform_driver au1xpsc_i2s_driver = {
409	.driver		= {
410		.name	= "au1xpsc_i2s",
411		.pm	= AU1XPSCI2S_PMOPS,
412	},
413	.probe		= au1xpsc_i2s_drvprobe,
414	.remove		= au1xpsc_i2s_drvremove,
415};
416
417module_platform_driver(au1xpsc_i2s_driver);
418
419MODULE_LICENSE("GPL");
420MODULE_DESCRIPTION("Au12x0/Au1550 PSC I2S ALSA ASoC audio driver");
421MODULE_AUTHOR("Manuel Lauss");
422