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!!!! */
50 static 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 */
58 static 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->snd_soc_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 */
71 static 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 */
112 static 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 */
144 static 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
155 static 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 */
200 static 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
207 static 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
284 out:
285 return 0;
286 }
287
288 static 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
322 static 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
330 static int au1xpsc_ac97_probe(struct snd_soc_dai *dai)
331 {
332 return au1xpsc_ac97_workdata ? 0 : -ENODEV;
333 }
334
335 static const struct snd_soc_dai_ops au1xpsc_ac97_dai_ops = {
336 .probe = au1xpsc_ac97_probe,
337 .startup = au1xpsc_ac97_startup,
338 .trigger = au1xpsc_ac97_trigger,
339 .hw_params = au1xpsc_ac97_hw_params,
340 };
341
342 static const struct snd_soc_dai_driver au1xpsc_ac97_dai_template = {
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
358 static const struct snd_soc_component_driver au1xpsc_ac97_component = {
359 .name = "au1xpsc-ac97",
360 .legacy_dai_naming = 1,
361 };
362
363 static int au1xpsc_ac97_drvprobe(struct platform_device *pdev)
364 {
365 int ret;
366 struct resource *dmares;
367 unsigned long sel;
368 struct au1xpsc_audio_data *wd;
369
370 wd = devm_kzalloc(&pdev->dev, sizeof(struct au1xpsc_audio_data),
371 GFP_KERNEL);
372 if (!wd)
373 return -ENOMEM;
374
375 mutex_init(&wd->lock);
376
377 wd->mmio = devm_platform_ioremap_resource(pdev, 0);
378 if (IS_ERR(wd->mmio))
379 return PTR_ERR(wd->mmio);
380
381 dmares = platform_get_resource(pdev, IORESOURCE_DMA, 0);
382 if (!dmares)
383 return -EBUSY;
384 wd->dmaids[SNDRV_PCM_STREAM_PLAYBACK] = dmares->start;
385
386 dmares = platform_get_resource(pdev, IORESOURCE_DMA, 1);
387 if (!dmares)
388 return -EBUSY;
389 wd->dmaids[SNDRV_PCM_STREAM_CAPTURE] = dmares->start;
390
391 /* configuration: max dma trigger threshold, enable ac97 */
392 wd->cfg = PSC_AC97CFG_RT_FIFO8 | PSC_AC97CFG_TT_FIFO8 |
393 PSC_AC97CFG_DE_ENABLE;
394
395 /* preserve PSC clock source set up by platform */
396 sel = __raw_readl(PSC_SEL(wd)) & PSC_SEL_CLK_MASK;
397 __raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
398 wmb(); /* drain writebuffer */
399 __raw_writel(0, PSC_SEL(wd));
400 wmb(); /* drain writebuffer */
401 __raw_writel(PSC_SEL_PS_AC97MODE | sel, PSC_SEL(wd));
402 wmb(); /* drain writebuffer */
403
404 /* name the DAI like this device instance ("au1xpsc-ac97.PSCINDEX") */
405 memcpy(&wd->dai_drv, &au1xpsc_ac97_dai_template,
406 sizeof(struct snd_soc_dai_driver));
407 wd->dai_drv.name = dev_name(&pdev->dev);
408
409 platform_set_drvdata(pdev, wd);
410
411 ret = snd_soc_set_ac97_ops(&psc_ac97_ops);
412 if (ret)
413 return ret;
414
415 ret = snd_soc_register_component(&pdev->dev, &au1xpsc_ac97_component,
416 &wd->dai_drv, 1);
417 if (ret)
418 return ret;
419
420 au1xpsc_ac97_workdata = wd;
421 return 0;
422 }
423
424 static void au1xpsc_ac97_drvremove(struct platform_device *pdev)
425 {
426 struct au1xpsc_audio_data *wd = platform_get_drvdata(pdev);
427
428 snd_soc_unregister_component(&pdev->dev);
429
430 /* disable PSC completely */
431 __raw_writel(0, AC97_CFG(wd));
432 wmb(); /* drain writebuffer */
433 __raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
434 wmb(); /* drain writebuffer */
435
436 au1xpsc_ac97_workdata = NULL; /* MDEV */
437 }
438
439 #ifdef CONFIG_PM
440 static int au1xpsc_ac97_drvsuspend(struct device *dev)
441 {
442 struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
443
444 /* save interesting registers and disable PSC */
445 wd->pm[0] = __raw_readl(PSC_SEL(wd));
446
447 __raw_writel(0, AC97_CFG(wd));
448 wmb(); /* drain writebuffer */
449 __raw_writel(PSC_CTRL_DISABLE, PSC_CTRL(wd));
450 wmb(); /* drain writebuffer */
451
452 return 0;
453 }
454
455 static int au1xpsc_ac97_drvresume(struct device *dev)
456 {
457 struct au1xpsc_audio_data *wd = dev_get_drvdata(dev);
458
459 /* restore PSC clock config */
460 __raw_writel(wd->pm[0] | PSC_SEL_PS_AC97MODE, PSC_SEL(wd));
461 wmb(); /* drain writebuffer */
462
463 /* after this point the ac97 core will cold-reset the codec.
464 * During cold-reset the PSC is reinitialized and the last
465 * configuration set up in hw_params() is restored.
466 */
467 return 0;
468 }
469
470 static const struct dev_pm_ops au1xpscac97_pmops = {
471 .suspend = au1xpsc_ac97_drvsuspend,
472 .resume = au1xpsc_ac97_drvresume,
473 };
474
475 #define AU1XPSCAC97_PMOPS &au1xpscac97_pmops
476
477 #else
478
479 #define AU1XPSCAC97_PMOPS NULL
480
481 #endif
482
483 static struct platform_driver au1xpsc_ac97_driver = {
484 .driver = {
485 .name = "au1xpsc_ac97",
486 .pm = AU1XPSCAC97_PMOPS,
487 },
488 .probe = au1xpsc_ac97_drvprobe,
489 .remove_new = au1xpsc_ac97_drvremove,
490 };
491
492 module_platform_driver(au1xpsc_ac97_driver);
493
494 MODULE_LICENSE("GPL");
495 MODULE_DESCRIPTION("Au12x0/Au1550 PSC AC97 ALSA ASoC audio driver");
496 MODULE_AUTHOR("Manuel Lauss");
497
498
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.