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sh_eth: fix EESIPR values for SH77{34|63}
[linux/fpc-iii.git] / sound / soc / bcm / bcm2835-i2s.c
blob6ba20498202ed36906b52096893a88867a79269f
1 /*
2 * ALSA SoC I2S Audio Layer for Broadcom BCM2835 SoC
3 *
4 * Author: Florian Meier <florian.meier@koalo.de>
5 * Copyright 2013
6 *
7 * Based on
8 * Raspberry Pi PCM I2S ALSA Driver
9 * Copyright (c) by Phil Poole 2013
10 *
11 * ALSA SoC I2S (McBSP) Audio Layer for TI DAVINCI processor
12 * Vladimir Barinov, <vbarinov@embeddedalley.com>
13 * Copyright (C) 2007 MontaVista Software, Inc., <source@mvista.com>
14 *
15 * OMAP ALSA SoC DAI driver using McBSP port
16 * Copyright (C) 2008 Nokia Corporation
17 * Contact: Jarkko Nikula <jarkko.nikula@bitmer.com>
18 * Peter Ujfalusi <peter.ujfalusi@ti.com>
19 *
20 * Freescale SSI ALSA SoC Digital Audio Interface (DAI) driver
21 * Author: Timur Tabi <timur@freescale.com>
22 * Copyright 2007-2010 Freescale Semiconductor, Inc.
23 *
24 * This program is free software; you can redistribute it and/or
25 * modify it under the terms of the GNU General Public License
26 * version 2 as published by the Free Software Foundation.
27 *
28 * This program is distributed in the hope that it will be useful, but
29 * WITHOUT ANY WARRANTY; without even the implied warranty of
30 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
31 * General Public License for more details.
32 */
33
34 #include <linux/clk.h>
35 #include <linux/delay.h>
36 #include <linux/device.h>
37 #include <linux/init.h>
38 #include <linux/io.h>
39 #include <linux/module.h>
40 #include <linux/of_address.h>
41 #include <linux/slab.h>
42
43 #include <sound/core.h>
44 #include <sound/dmaengine_pcm.h>
45 #include <sound/initval.h>
46 #include <sound/pcm.h>
47 #include <sound/pcm_params.h>
48 #include <sound/soc.h>
49
50 /* I2S registers */
51 #define BCM2835_I2S_CS_A_REG 0x00
52 #define BCM2835_I2S_FIFO_A_REG 0x04
53 #define BCM2835_I2S_MODE_A_REG 0x08
54 #define BCM2835_I2S_RXC_A_REG 0x0c
55 #define BCM2835_I2S_TXC_A_REG 0x10
56 #define BCM2835_I2S_DREQ_A_REG 0x14
57 #define BCM2835_I2S_INTEN_A_REG 0x18
58 #define BCM2835_I2S_INTSTC_A_REG 0x1c
59 #define BCM2835_I2S_GRAY_REG 0x20
60
61 /* I2S register settings */
62 #define BCM2835_I2S_STBY BIT(25)
63 #define BCM2835_I2S_SYNC BIT(24)
64 #define BCM2835_I2S_RXSEX BIT(23)
65 #define BCM2835_I2S_RXF BIT(22)
66 #define BCM2835_I2S_TXE BIT(21)
67 #define BCM2835_I2S_RXD BIT(20)
68 #define BCM2835_I2S_TXD BIT(19)
69 #define BCM2835_I2S_RXR BIT(18)
70 #define BCM2835_I2S_TXW BIT(17)
71 #define BCM2835_I2S_CS_RXERR BIT(16)
72 #define BCM2835_I2S_CS_TXERR BIT(15)
73 #define BCM2835_I2S_RXSYNC BIT(14)
74 #define BCM2835_I2S_TXSYNC BIT(13)
75 #define BCM2835_I2S_DMAEN BIT(9)
76 #define BCM2835_I2S_RXTHR(v) ((v) << 7)
77 #define BCM2835_I2S_TXTHR(v) ((v) << 5)
78 #define BCM2835_I2S_RXCLR BIT(4)
79 #define BCM2835_I2S_TXCLR BIT(3)
80 #define BCM2835_I2S_TXON BIT(2)
81 #define BCM2835_I2S_RXON BIT(1)
82 #define BCM2835_I2S_EN (1)
83
84 #define BCM2835_I2S_CLKDIS BIT(28)
85 #define BCM2835_I2S_PDMN BIT(27)
86 #define BCM2835_I2S_PDME BIT(26)
87 #define BCM2835_I2S_FRXP BIT(25)
88 #define BCM2835_I2S_FTXP BIT(24)
89 #define BCM2835_I2S_CLKM BIT(23)
90 #define BCM2835_I2S_CLKI BIT(22)
91 #define BCM2835_I2S_FSM BIT(21)
92 #define BCM2835_I2S_FSI BIT(20)
93 #define BCM2835_I2S_FLEN(v) ((v) << 10)
94 #define BCM2835_I2S_FSLEN(v) (v)
95
96 #define BCM2835_I2S_CHWEX BIT(15)
97 #define BCM2835_I2S_CHEN BIT(14)
98 #define BCM2835_I2S_CHPOS(v) ((v) << 4)
99 #define BCM2835_I2S_CHWID(v) (v)
100 #define BCM2835_I2S_CH1(v) ((v) << 16)
101 #define BCM2835_I2S_CH2(v) (v)
102
103 #define BCM2835_I2S_TX_PANIC(v) ((v) << 24)
104 #define BCM2835_I2S_RX_PANIC(v) ((v) << 16)
105 #define BCM2835_I2S_TX(v) ((v) << 8)
106 #define BCM2835_I2S_RX(v) (v)
107
108 #define BCM2835_I2S_INT_RXERR BIT(3)
109 #define BCM2835_I2S_INT_TXERR BIT(2)
110 #define BCM2835_I2S_INT_RXR BIT(1)
111 #define BCM2835_I2S_INT_TXW BIT(0)
112
113 /* General device struct */
114 struct bcm2835_i2s_dev {
115 struct device *dev;
116 struct snd_dmaengine_dai_dma_data dma_data[2];
117 unsigned int fmt;
118 unsigned int bclk_ratio;
119
120 struct regmap *i2s_regmap;
121 struct clk *clk;
122 bool clk_prepared;
123 };
124
125 static void bcm2835_i2s_start_clock(struct bcm2835_i2s_dev *dev)
126 {
127 unsigned int master = dev->fmt & SND_SOC_DAIFMT_MASTER_MASK;
128
129 if (dev->clk_prepared)
130 return;
131
132 switch (master) {
133 case SND_SOC_DAIFMT_CBS_CFS:
134 case SND_SOC_DAIFMT_CBS_CFM:
135 clk_prepare_enable(dev->clk);
136 dev->clk_prepared = true;
137 break;
138 default:
139 break;
140 }
141 }
142
143 static void bcm2835_i2s_stop_clock(struct bcm2835_i2s_dev *dev)
144 {
145 if (dev->clk_prepared)
146 clk_disable_unprepare(dev->clk);
147 dev->clk_prepared = false;
148 }
149
150 static void bcm2835_i2s_clear_fifos(struct bcm2835_i2s_dev *dev,
151 bool tx, bool rx)
152 {
153 int timeout = 1000;
154 uint32_t syncval;
155 uint32_t csreg;
156 uint32_t i2s_active_state;
157 bool clk_was_prepared;
158 uint32_t off;
159 uint32_t clr;
160
161 off = tx ? BCM2835_I2S_TXON : 0;
162 off |= rx ? BCM2835_I2S_RXON : 0;
163
164 clr = tx ? BCM2835_I2S_TXCLR : 0;
165 clr |= rx ? BCM2835_I2S_RXCLR : 0;
166
167 /* Backup the current state */
168 regmap_read(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, &csreg);
169 i2s_active_state = csreg & (BCM2835_I2S_RXON | BCM2835_I2S_TXON);
170
171 /* Start clock if not running */
172 clk_was_prepared = dev->clk_prepared;
173 if (!clk_was_prepared)
174 bcm2835_i2s_start_clock(dev);
175
176 /* Stop I2S module */
177 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, off, 0);
178
179 /*
180 * Clear the FIFOs
181 * Requires at least 2 PCM clock cycles to take effect
182 */
183 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, clr, clr);
184
185 /* Wait for 2 PCM clock cycles */
186
187 /*
188 * Toggle the SYNC flag. After 2 PCM clock cycles it can be read back
189 * FIXME: This does not seem to work for slave mode!
190 */
191 regmap_read(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, &syncval);
192 syncval &= BCM2835_I2S_SYNC;
193
194 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG,
195 BCM2835_I2S_SYNC, ~syncval);
196
197 /* Wait for the SYNC flag changing it's state */
198 while (--timeout) {
199 regmap_read(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, &csreg);
200 if ((csreg & BCM2835_I2S_SYNC) != syncval)
201 break;
202 }
203
204 if (!timeout)
205 dev_err(dev->dev, "I2S SYNC error!\n");
206
207 /* Stop clock if it was not running before */
208 if (!clk_was_prepared)
209 bcm2835_i2s_stop_clock(dev);
210
211 /* Restore I2S state */
212 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG,
213 BCM2835_I2S_RXON | BCM2835_I2S_TXON, i2s_active_state);
214 }
215
216 static int bcm2835_i2s_set_dai_fmt(struct snd_soc_dai *dai,
217 unsigned int fmt)
218 {
219 struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
220 dev->fmt = fmt;
221 return 0;
222 }
223
224 static int bcm2835_i2s_set_dai_bclk_ratio(struct snd_soc_dai *dai,
225 unsigned int ratio)
226 {
227 struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
228 dev->bclk_ratio = ratio;
229 return 0;
230 }
231
232 static int bcm2835_i2s_hw_params(struct snd_pcm_substream *substream,
233 struct snd_pcm_hw_params *params,
234 struct snd_soc_dai *dai)
235 {
236 struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
237 unsigned int sampling_rate = params_rate(params);
238 unsigned int data_length, data_delay, bclk_ratio;
239 unsigned int ch1pos, ch2pos, mode, format;
240 uint32_t csreg;
241
242 /*
243 * If a stream is already enabled,
244 * the registers are already set properly.
245 */
246 regmap_read(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, &csreg);
247
248 if (csreg & (BCM2835_I2S_TXON | BCM2835_I2S_RXON))
249 return 0;
250
251 /*
252 * Adjust the data length according to the format.
253 * We prefill the half frame length with an integer
254 * divider of 2400 as explained at the clock settings.
255 * Maybe it is overwritten there, if the Integer mode
256 * does not apply.
257 */
258 switch (params_format(params)) {
259 case SNDRV_PCM_FORMAT_S16_LE:
260 data_length = 16;
261 break;
262 case SNDRV_PCM_FORMAT_S24_LE:
263 data_length = 24;
264 break;
265 case SNDRV_PCM_FORMAT_S32_LE:
266 data_length = 32;
267 break;
268 default:
269 return -EINVAL;
270 }
271
272 /* If bclk_ratio already set, use that one. */
273 if (dev->bclk_ratio)
274 bclk_ratio = dev->bclk_ratio;
275 else
276 /* otherwise calculate a fitting block ratio */
277 bclk_ratio = 2 * data_length;
278
279 /* Clock should only be set up here if CPU is clock master */
280 switch (dev->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
281 case SND_SOC_DAIFMT_CBS_CFS:
282 case SND_SOC_DAIFMT_CBS_CFM:
283 clk_set_rate(dev->clk, sampling_rate * bclk_ratio);
284 break;
285 default:
286 break;
287 }
288
289 /* Setup the frame format */
290 format = BCM2835_I2S_CHEN;
291
292 if (data_length >= 24)
293 format |= BCM2835_I2S_CHWEX;
294
295 format |= BCM2835_I2S_CHWID((data_length-8)&0xf);
296
297 switch (dev->fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
298 case SND_SOC_DAIFMT_I2S:
299 data_delay = 1;
300 break;
301 default:
302 /*
303 * TODO
304 * Others are possible but are not implemented at the moment.
305 */
306 dev_err(dev->dev, "%s:bad format\n", __func__);
307 return -EINVAL;
308 }
309
310 ch1pos = data_delay;
311 ch2pos = bclk_ratio / 2 + data_delay;
312
313 switch (params_channels(params)) {
314 case 2:
315 format = BCM2835_I2S_CH1(format) | BCM2835_I2S_CH2(format);
316 format |= BCM2835_I2S_CH1(BCM2835_I2S_CHPOS(ch1pos));
317 format |= BCM2835_I2S_CH2(BCM2835_I2S_CHPOS(ch2pos));
318 break;
319 default:
320 return -EINVAL;
321 }
322
323 /*
324 * Set format for both streams.
325 * We cannot set another frame length
326 * (and therefore word length) anyway,
327 * so the format will be the same.
328 */
329 regmap_write(dev->i2s_regmap, BCM2835_I2S_RXC_A_REG, format);
330 regmap_write(dev->i2s_regmap, BCM2835_I2S_TXC_A_REG, format);
331
332 /* Setup the I2S mode */
333 mode = 0;
334
335 if (data_length <= 16) {
336 /*
337 * Use frame packed mode (2 channels per 32 bit word)
338 * We cannot set another frame length in the second stream
339 * (and therefore word length) anyway,
340 * so the format will be the same.
341 */
342 mode |= BCM2835_I2S_FTXP | BCM2835_I2S_FRXP;
343 }
344
345 mode |= BCM2835_I2S_FLEN(bclk_ratio - 1);
346 mode |= BCM2835_I2S_FSLEN(bclk_ratio / 2);
347
348 /* Master or slave? */
349 switch (dev->fmt & SND_SOC_DAIFMT_MASTER_MASK) {
350 case SND_SOC_DAIFMT_CBS_CFS:
351 /* CPU is master */
352 break;
353 case SND_SOC_DAIFMT_CBM_CFS:
354 /*
355 * CODEC is bit clock master
356 * CPU is frame master
357 */
358 mode |= BCM2835_I2S_CLKM;
359 break;
360 case SND_SOC_DAIFMT_CBS_CFM:
361 /*
362 * CODEC is frame master
363 * CPU is bit clock master
364 */
365 mode |= BCM2835_I2S_FSM;
366 break;
367 case SND_SOC_DAIFMT_CBM_CFM:
368 /* CODEC is master */
369 mode |= BCM2835_I2S_CLKM;
370 mode |= BCM2835_I2S_FSM;
371 break;
372 default:
373 dev_err(dev->dev, "%s:bad master\n", __func__);
374 return -EINVAL;
375 }
376
377 /*
378 * Invert clocks?
379 *
380 * The BCM approach seems to be inverted to the classical I2S approach.
381 */
382 switch (dev->fmt & SND_SOC_DAIFMT_INV_MASK) {
383 case SND_SOC_DAIFMT_NB_NF:
384 /* None. Therefore, both for BCM */
385 mode |= BCM2835_I2S_CLKI;
386 mode |= BCM2835_I2S_FSI;
387 break;
388 case SND_SOC_DAIFMT_IB_IF:
389 /* Both. Therefore, none for BCM */
390 break;
391 case SND_SOC_DAIFMT_NB_IF:
392 /*
393 * Invert only frame sync. Therefore,
394 * invert only bit clock for BCM
395 */
396 mode |= BCM2835_I2S_CLKI;
397 break;
398 case SND_SOC_DAIFMT_IB_NF:
399 /*
400 * Invert only bit clock. Therefore,
401 * invert only frame sync for BCM
402 */
403 mode |= BCM2835_I2S_FSI;
404 break;
405 default:
406 return -EINVAL;
407 }
408
409 regmap_write(dev->i2s_regmap, BCM2835_I2S_MODE_A_REG, mode);
410
411 /* Setup the DMA parameters */
412 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG,
413 BCM2835_I2S_RXTHR(1)
414 | BCM2835_I2S_TXTHR(1)
415 | BCM2835_I2S_DMAEN, 0xffffffff);
416
417 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_DREQ_A_REG,
418 BCM2835_I2S_TX_PANIC(0x10)
419 | BCM2835_I2S_RX_PANIC(0x30)
420 | BCM2835_I2S_TX(0x30)
421 | BCM2835_I2S_RX(0x20), 0xffffffff);
422
423 /* Clear FIFOs */
424 bcm2835_i2s_clear_fifos(dev, true, true);
425
426 return 0;
427 }
428
429 static int bcm2835_i2s_prepare(struct snd_pcm_substream *substream,
430 struct snd_soc_dai *dai)
431 {
432 struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
433 uint32_t cs_reg;
434
435 bcm2835_i2s_start_clock(dev);
436
437 /*
438 * Clear both FIFOs if the one that should be started
439 * is not empty at the moment. This should only happen
440 * after overrun. Otherwise, hw_params would have cleared
441 * the FIFO.
442 */
443 regmap_read(dev->i2s_regmap, BCM2835_I2S_CS_A_REG, &cs_reg);
444
445 if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK
446 && !(cs_reg & BCM2835_I2S_TXE))
447 bcm2835_i2s_clear_fifos(dev, true, false);
448 else if (substream->stream == SNDRV_PCM_STREAM_CAPTURE
449 && (cs_reg & BCM2835_I2S_RXD))
450 bcm2835_i2s_clear_fifos(dev, false, true);
451
452 return 0;
453 }
454
455 static void bcm2835_i2s_stop(struct bcm2835_i2s_dev *dev,
456 struct snd_pcm_substream *substream,
457 struct snd_soc_dai *dai)
458 {
459 uint32_t mask;
460
461 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
462 mask = BCM2835_I2S_RXON;
463 else
464 mask = BCM2835_I2S_TXON;
465
466 regmap_update_bits(dev->i2s_regmap,
467 BCM2835_I2S_CS_A_REG, mask, 0);
468
469 /* Stop also the clock when not SND_SOC_DAIFMT_CONT */
470 if (!dai->active && !(dev->fmt & SND_SOC_DAIFMT_CONT))
471 bcm2835_i2s_stop_clock(dev);
472 }
473
474 static int bcm2835_i2s_trigger(struct snd_pcm_substream *substream, int cmd,
475 struct snd_soc_dai *dai)
476 {
477 struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
478 uint32_t mask;
479
480 switch (cmd) {
481 case SNDRV_PCM_TRIGGER_START:
482 case SNDRV_PCM_TRIGGER_RESUME:
483 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
484 bcm2835_i2s_start_clock(dev);
485
486 if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
487 mask = BCM2835_I2S_RXON;
488 else
489 mask = BCM2835_I2S_TXON;
490
491 regmap_update_bits(dev->i2s_regmap,
492 BCM2835_I2S_CS_A_REG, mask, mask);
493 break;
494
495 case SNDRV_PCM_TRIGGER_STOP:
496 case SNDRV_PCM_TRIGGER_SUSPEND:
497 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
498 bcm2835_i2s_stop(dev, substream, dai);
499 break;
500 default:
501 return -EINVAL;
502 }
503
504 return 0;
505 }
506
507 static int bcm2835_i2s_startup(struct snd_pcm_substream *substream,
508 struct snd_soc_dai *dai)
509 {
510 struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
511
512 if (dai->active)
513 return 0;
514
515 /* Should this still be running stop it */
516 bcm2835_i2s_stop_clock(dev);
517
518 /* Enable PCM block */
519 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG,
520 BCM2835_I2S_EN, BCM2835_I2S_EN);
521
522 /*
523 * Disable STBY.
524 * Requires at least 4 PCM clock cycles to take effect.
525 */
526 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG,
527 BCM2835_I2S_STBY, BCM2835_I2S_STBY);
528
529 return 0;
530 }
531
532 static void bcm2835_i2s_shutdown(struct snd_pcm_substream *substream,
533 struct snd_soc_dai *dai)
534 {
535 struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
536
537 bcm2835_i2s_stop(dev, substream, dai);
538
539 /* If both streams are stopped, disable module and clock */
540 if (dai->active)
541 return;
542
543 /* Disable the module */
544 regmap_update_bits(dev->i2s_regmap, BCM2835_I2S_CS_A_REG,
545 BCM2835_I2S_EN, 0);
546
547 /*
548 * Stopping clock is necessary, because stop does
549 * not stop the clock when SND_SOC_DAIFMT_CONT
550 */
551 bcm2835_i2s_stop_clock(dev);
552 }
553
554 static const struct snd_soc_dai_ops bcm2835_i2s_dai_ops = {
555 .startup = bcm2835_i2s_startup,
556 .shutdown = bcm2835_i2s_shutdown,
557 .prepare = bcm2835_i2s_prepare,
558 .trigger = bcm2835_i2s_trigger,
559 .hw_params = bcm2835_i2s_hw_params,
560 .set_fmt = bcm2835_i2s_set_dai_fmt,
561 .set_bclk_ratio = bcm2835_i2s_set_dai_bclk_ratio,
562 };
563
564 static int bcm2835_i2s_dai_probe(struct snd_soc_dai *dai)
565 {
566 struct bcm2835_i2s_dev *dev = snd_soc_dai_get_drvdata(dai);
567
568 snd_soc_dai_init_dma_data(dai,
569 &dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK],
570 &dev->dma_data[SNDRV_PCM_STREAM_CAPTURE]);
571
572 return 0;
573 }
574
575 static struct snd_soc_dai_driver bcm2835_i2s_dai = {
576 .name = "bcm2835-i2s",
577 .probe = bcm2835_i2s_dai_probe,
578 .playback = {
579 .channels_min = 2,
580 .channels_max = 2,
581 .rates = SNDRV_PCM_RATE_8000_192000,
582 .formats = SNDRV_PCM_FMTBIT_S16_LE
583 | SNDRV_PCM_FMTBIT_S24_LE
584 | SNDRV_PCM_FMTBIT_S32_LE
585 },
586 .capture = {
587 .channels_min = 2,
588 .channels_max = 2,
589 .rates = SNDRV_PCM_RATE_8000_192000,
590 .formats = SNDRV_PCM_FMTBIT_S16_LE
591 | SNDRV_PCM_FMTBIT_S24_LE
592 | SNDRV_PCM_FMTBIT_S32_LE
593 },
594 .ops = &bcm2835_i2s_dai_ops,
595 .symmetric_rates = 1
596 };
597
598 static bool bcm2835_i2s_volatile_reg(struct device *dev, unsigned int reg)
599 {
600 switch (reg) {
601 case BCM2835_I2S_CS_A_REG:
602 case BCM2835_I2S_FIFO_A_REG:
603 case BCM2835_I2S_INTSTC_A_REG:
604 case BCM2835_I2S_GRAY_REG:
605 return true;
606 default:
607 return false;
608 };
609 }
610
611 static bool bcm2835_i2s_precious_reg(struct device *dev, unsigned int reg)
612 {
613 switch (reg) {
614 case BCM2835_I2S_FIFO_A_REG:
615 return true;
616 default:
617 return false;
618 };
619 }
620
621 static const struct regmap_config bcm2835_regmap_config = {
622 .reg_bits = 32,
623 .reg_stride = 4,
624 .val_bits = 32,
625 .max_register = BCM2835_I2S_GRAY_REG,
626 .precious_reg = bcm2835_i2s_precious_reg,
627 .volatile_reg = bcm2835_i2s_volatile_reg,
628 .cache_type = REGCACHE_RBTREE,
629 };
630
631 static const struct snd_soc_component_driver bcm2835_i2s_component = {
632 .name = "bcm2835-i2s-comp",
633 };
634
635 static int bcm2835_i2s_probe(struct platform_device *pdev)
636 {
637 struct bcm2835_i2s_dev *dev;
638 int ret;
639 struct resource *mem;
640 void __iomem *base;
641 const __be32 *addr;
642 dma_addr_t dma_base;
643
644 dev = devm_kzalloc(&pdev->dev, sizeof(*dev),
645 GFP_KERNEL);
646 if (!dev)
647 return -ENOMEM;
648
649 /* get the clock */
650 dev->clk_prepared = false;
651 dev->clk = devm_clk_get(&pdev->dev, NULL);
652 if (IS_ERR(dev->clk)) {
653 dev_err(&pdev->dev, "could not get clk: %ld\n",
654 PTR_ERR(dev->clk));
655 return PTR_ERR(dev->clk);
656 }
657
658 /* Request ioarea */
659 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
660 base = devm_ioremap_resource(&pdev->dev, mem);
661 if (IS_ERR(base))
662 return PTR_ERR(base);
663
664 dev->i2s_regmap = devm_regmap_init_mmio(&pdev->dev, base,
665 &bcm2835_regmap_config);
666 if (IS_ERR(dev->i2s_regmap))
667 return PTR_ERR(dev->i2s_regmap);
668
669 /* Set the DMA address - we have to parse DT ourselves */
670 addr = of_get_address(pdev->dev.of_node, 0, NULL, NULL);
671 if (!addr) {
672 dev_err(&pdev->dev, "could not get DMA-register address\n");
673 return -EINVAL;
674 }
675 dma_base = be32_to_cpup(addr);
676
677 dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].addr =
678 dma_base + BCM2835_I2S_FIFO_A_REG;
679
680 dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].addr =
681 dma_base + BCM2835_I2S_FIFO_A_REG;
682
683 /* Set the bus width */
684 dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].addr_width =
685 DMA_SLAVE_BUSWIDTH_4_BYTES;
686 dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].addr_width =
687 DMA_SLAVE_BUSWIDTH_4_BYTES;
688
689 /* Set burst */
690 dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].maxburst = 2;
691 dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].maxburst = 2;
692
693 /*
694 * Set the PACK flag to enable S16_LE support (2 S16_LE values
695 * packed into 32-bit transfers).
696 */
697 dev->dma_data[SNDRV_PCM_STREAM_PLAYBACK].flags =
698 SND_DMAENGINE_PCM_DAI_FLAG_PACK;
699 dev->dma_data[SNDRV_PCM_STREAM_CAPTURE].flags =
700 SND_DMAENGINE_PCM_DAI_FLAG_PACK;
701
702 /* BCLK ratio - use default */
703 dev->bclk_ratio = 0;
704
705 /* Store the pdev */
706 dev->dev = &pdev->dev;
707 dev_set_drvdata(&pdev->dev, dev);
708
709 ret = devm_snd_soc_register_component(&pdev->dev,
710 &bcm2835_i2s_component, &bcm2835_i2s_dai, 1);
711 if (ret) {
712 dev_err(&pdev->dev, "Could not register DAI: %d\n", ret);
713 return ret;
714 }
715
716 ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
717 if (ret) {
718 dev_err(&pdev->dev, "Could not register PCM: %d\n", ret);
719 return ret;
720 }
721
722 return 0;
723 }
724
725 static const struct of_device_id bcm2835_i2s_of_match[] = {
726 { .compatible = "brcm,bcm2835-i2s", },
727 {},
728 };
729
730 MODULE_DEVICE_TABLE(of, bcm2835_i2s_of_match);
731
732 static struct platform_driver bcm2835_i2s_driver = {
733 .probe = bcm2835_i2s_probe,
734 .driver = {
735 .name = "bcm2835-i2s",
736 .of_match_table = bcm2835_i2s_of_match,
737 },
738 };
739
740 module_platform_driver(bcm2835_i2s_driver);
741
742 MODULE_ALIAS("platform:bcm2835-i2s");
743 MODULE_DESCRIPTION("BCM2835 I2S interface");
744 MODULE_AUTHOR("Florian Meier <florian.meier@koalo.de>");
745 MODULE_LICENSE("GPL v2");
Linux with added FPC-III support