xref: /openbmc/linux/sound/soc/bcm/cygnus-pcm.c (revision cfdfc14e)
1 /*
2  * Copyright (C) 2014-2015 Broadcom Corporation
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License as
6  * published by the Free Software Foundation version 2.
7  *
8  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
9  * kind, whether express or implied; without even the implied warranty
10  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 #include <linux/debugfs.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/init.h>
16 #include <linux/io.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
19 #include <linux/timer.h>
20 #include <sound/core.h>
21 #include <sound/pcm.h>
22 #include <sound/pcm_params.h>
23 #include <sound/soc.h>
24 #include <sound/soc-dai.h>
25 
26 #include "cygnus-ssp.h"
27 
28 /* Register offset needed for ASoC PCM module */
29 
30 #define INTH_R5F_STATUS_OFFSET     0x040
31 #define INTH_R5F_CLEAR_OFFSET      0x048
32 #define INTH_R5F_MASK_SET_OFFSET   0x050
33 #define INTH_R5F_MASK_CLEAR_OFFSET 0x054
34 
35 #define BF_REARM_FREE_MARK_OFFSET 0x344
36 #define BF_REARM_FULL_MARK_OFFSET 0x348
37 
38 /* Ring Buffer Ctrl Regs --- Start */
39 /* AUD_FMM_BF_CTRL_SOURCECH_RINGBUF_X_RDADDR_REG_BASE */
40 #define SRC_RBUF_0_RDADDR_OFFSET 0x500
41 #define SRC_RBUF_1_RDADDR_OFFSET 0x518
42 #define SRC_RBUF_2_RDADDR_OFFSET 0x530
43 #define SRC_RBUF_3_RDADDR_OFFSET 0x548
44 #define SRC_RBUF_4_RDADDR_OFFSET 0x560
45 #define SRC_RBUF_5_RDADDR_OFFSET 0x578
46 #define SRC_RBUF_6_RDADDR_OFFSET 0x590
47 
48 /* AUD_FMM_BF_CTRL_SOURCECH_RINGBUF_X_WRADDR_REG_BASE */
49 #define SRC_RBUF_0_WRADDR_OFFSET 0x504
50 #define SRC_RBUF_1_WRADDR_OFFSET 0x51c
51 #define SRC_RBUF_2_WRADDR_OFFSET 0x534
52 #define SRC_RBUF_3_WRADDR_OFFSET 0x54c
53 #define SRC_RBUF_4_WRADDR_OFFSET 0x564
54 #define SRC_RBUF_5_WRADDR_OFFSET 0x57c
55 #define SRC_RBUF_6_WRADDR_OFFSET 0x594
56 
57 /* AUD_FMM_BF_CTRL_SOURCECH_RINGBUF_X_BASEADDR_REG_BASE */
58 #define SRC_RBUF_0_BASEADDR_OFFSET 0x508
59 #define SRC_RBUF_1_BASEADDR_OFFSET 0x520
60 #define SRC_RBUF_2_BASEADDR_OFFSET 0x538
61 #define SRC_RBUF_3_BASEADDR_OFFSET 0x550
62 #define SRC_RBUF_4_BASEADDR_OFFSET 0x568
63 #define SRC_RBUF_5_BASEADDR_OFFSET 0x580
64 #define SRC_RBUF_6_BASEADDR_OFFSET 0x598
65 
66 /* AUD_FMM_BF_CTRL_SOURCECH_RINGBUF_X_ENDADDR_REG_BASE */
67 #define SRC_RBUF_0_ENDADDR_OFFSET 0x50c
68 #define SRC_RBUF_1_ENDADDR_OFFSET 0x524
69 #define SRC_RBUF_2_ENDADDR_OFFSET 0x53c
70 #define SRC_RBUF_3_ENDADDR_OFFSET 0x554
71 #define SRC_RBUF_4_ENDADDR_OFFSET 0x56c
72 #define SRC_RBUF_5_ENDADDR_OFFSET 0x584
73 #define SRC_RBUF_6_ENDADDR_OFFSET 0x59c
74 
75 /* AUD_FMM_BF_CTRL_SOURCECH_RINGBUF_X_FREE_MARK_REG_BASE */
76 #define SRC_RBUF_0_FREE_MARK_OFFSET 0x510
77 #define SRC_RBUF_1_FREE_MARK_OFFSET 0x528
78 #define SRC_RBUF_2_FREE_MARK_OFFSET 0x540
79 #define SRC_RBUF_3_FREE_MARK_OFFSET 0x558
80 #define SRC_RBUF_4_FREE_MARK_OFFSET 0x570
81 #define SRC_RBUF_5_FREE_MARK_OFFSET 0x588
82 #define SRC_RBUF_6_FREE_MARK_OFFSET 0x5a0
83 
84 /* AUD_FMM_BF_CTRL_DESTCH_RINGBUF_X_RDADDR_REG_BASE */
85 #define DST_RBUF_0_RDADDR_OFFSET 0x5c0
86 #define DST_RBUF_1_RDADDR_OFFSET 0x5d8
87 #define DST_RBUF_2_RDADDR_OFFSET 0x5f0
88 #define DST_RBUF_3_RDADDR_OFFSET 0x608
89 #define DST_RBUF_4_RDADDR_OFFSET 0x620
90 #define DST_RBUF_5_RDADDR_OFFSET 0x638
91 
92 /* AUD_FMM_BF_CTRL_DESTCH_RINGBUF_X_WRADDR_REG_BASE */
93 #define DST_RBUF_0_WRADDR_OFFSET 0x5c4
94 #define DST_RBUF_1_WRADDR_OFFSET 0x5dc
95 #define DST_RBUF_2_WRADDR_OFFSET 0x5f4
96 #define DST_RBUF_3_WRADDR_OFFSET 0x60c
97 #define DST_RBUF_4_WRADDR_OFFSET 0x624
98 #define DST_RBUF_5_WRADDR_OFFSET 0x63c
99 
100 /* AUD_FMM_BF_CTRL_DESTCH_RINGBUF_X_BASEADDR_REG_BASE */
101 #define DST_RBUF_0_BASEADDR_OFFSET 0x5c8
102 #define DST_RBUF_1_BASEADDR_OFFSET 0x5e0
103 #define DST_RBUF_2_BASEADDR_OFFSET 0x5f8
104 #define DST_RBUF_3_BASEADDR_OFFSET 0x610
105 #define DST_RBUF_4_BASEADDR_OFFSET 0x628
106 #define DST_RBUF_5_BASEADDR_OFFSET 0x640
107 
108 /* AUD_FMM_BF_CTRL_DESTCH_RINGBUF_X_ENDADDR_REG_BASE */
109 #define DST_RBUF_0_ENDADDR_OFFSET 0x5cc
110 #define DST_RBUF_1_ENDADDR_OFFSET 0x5e4
111 #define DST_RBUF_2_ENDADDR_OFFSET 0x5fc
112 #define DST_RBUF_3_ENDADDR_OFFSET 0x614
113 #define DST_RBUF_4_ENDADDR_OFFSET 0x62c
114 #define DST_RBUF_5_ENDADDR_OFFSET 0x644
115 
116 /* AUD_FMM_BF_CTRL_DESTCH_RINGBUF_X_FULL_MARK_REG_BASE */
117 #define DST_RBUF_0_FULL_MARK_OFFSET 0x5d0
118 #define DST_RBUF_1_FULL_MARK_OFFSET 0x5e8
119 #define DST_RBUF_2_FULL_MARK_OFFSET 0x600
120 #define DST_RBUF_3_FULL_MARK_OFFSET 0x618
121 #define DST_RBUF_4_FULL_MARK_OFFSET 0x630
122 #define DST_RBUF_5_FULL_MARK_OFFSET 0x648
123 /* Ring Buffer Ctrl Regs --- End */
124 
125 /* Error Status Regs --- Start */
126 /* AUD_FMM_BF_ESR_ESRX_STATUS_REG_BASE */
127 #define ESR0_STATUS_OFFSET 0x900
128 #define ESR1_STATUS_OFFSET 0x918
129 #define ESR2_STATUS_OFFSET 0x930
130 #define ESR3_STATUS_OFFSET 0x948
131 #define ESR4_STATUS_OFFSET 0x960
132 
133 /* AUD_FMM_BF_ESR_ESRX_STATUS_CLEAR_REG_BASE */
134 #define ESR0_STATUS_CLR_OFFSET 0x908
135 #define ESR1_STATUS_CLR_OFFSET 0x920
136 #define ESR2_STATUS_CLR_OFFSET 0x938
137 #define ESR3_STATUS_CLR_OFFSET 0x950
138 #define ESR4_STATUS_CLR_OFFSET 0x968
139 
140 /* AUD_FMM_BF_ESR_ESRX_MASK_REG_BASE */
141 #define ESR0_MASK_STATUS_OFFSET 0x90c
142 #define ESR1_MASK_STATUS_OFFSET 0x924
143 #define ESR2_MASK_STATUS_OFFSET 0x93c
144 #define ESR3_MASK_STATUS_OFFSET 0x954
145 #define ESR4_MASK_STATUS_OFFSET 0x96c
146 
147 /* AUD_FMM_BF_ESR_ESRX_MASK_SET_REG_BASE */
148 #define ESR0_MASK_SET_OFFSET 0x910
149 #define ESR1_MASK_SET_OFFSET 0x928
150 #define ESR2_MASK_SET_OFFSET 0x940
151 #define ESR3_MASK_SET_OFFSET 0x958
152 #define ESR4_MASK_SET_OFFSET 0x970
153 
154 /* AUD_FMM_BF_ESR_ESRX_MASK_CLEAR_REG_BASE */
155 #define ESR0_MASK_CLR_OFFSET 0x914
156 #define ESR1_MASK_CLR_OFFSET 0x92c
157 #define ESR2_MASK_CLR_OFFSET 0x944
158 #define ESR3_MASK_CLR_OFFSET 0x95c
159 #define ESR4_MASK_CLR_OFFSET 0x974
160 /* Error Status Regs --- End */
161 
162 #define R5F_ESR0_SHIFT  0    /* esr0 = fifo underflow */
163 #define R5F_ESR1_SHIFT  1    /* esr1 = ringbuf underflow */
164 #define R5F_ESR2_SHIFT  2    /* esr2 = ringbuf overflow */
165 #define R5F_ESR3_SHIFT  3    /* esr3 = freemark */
166 #define R5F_ESR4_SHIFT  4    /* esr4 = fullmark */
167 
168 
169 /* Mask for R5F register.  Set all relevant interrupt for playback handler */
170 #define ANY_PLAYBACK_IRQ  (BIT(R5F_ESR0_SHIFT) | \
171 			   BIT(R5F_ESR1_SHIFT) | \
172 			   BIT(R5F_ESR3_SHIFT))
173 
174 /* Mask for R5F register.  Set all relevant interrupt for capture handler */
175 #define ANY_CAPTURE_IRQ   (BIT(R5F_ESR2_SHIFT) | BIT(R5F_ESR4_SHIFT))
176 
177 /*
178  * PERIOD_BYTES_MIN is the number of bytes to at which the interrupt will tick.
179  * This number should be a multiple of 256. Minimum value is 256
180  */
181 #define PERIOD_BYTES_MIN 0x100
182 
183 static const struct snd_pcm_hardware cygnus_pcm_hw = {
184 	.info = SNDRV_PCM_INFO_MMAP |
185 			SNDRV_PCM_INFO_MMAP_VALID |
186 			SNDRV_PCM_INFO_INTERLEAVED,
187 	.formats = SNDRV_PCM_FMTBIT_S16_LE |
188 			SNDRV_PCM_FMTBIT_S32_LE,
189 
190 	/* A period is basically an interrupt */
191 	.period_bytes_min = PERIOD_BYTES_MIN,
192 	.period_bytes_max = 0x10000,
193 
194 	/* period_min/max gives range of approx interrupts per buffer */
195 	.periods_min = 2,
196 	.periods_max = 8,
197 
198 	/*
199 	 * maximum buffer size in bytes = period_bytes_max * periods_max
200 	 * We allocate this amount of data for each enabled channel
201 	 */
202 	.buffer_bytes_max = 4 * 0x8000,
203 };
204 
205 static u64 cygnus_dma_dmamask = DMA_BIT_MASK(32);
206 
207 static struct cygnus_aio_port *cygnus_dai_get_dma_data(
208 				struct snd_pcm_substream *substream)
209 {
210 	struct snd_soc_pcm_runtime *soc_runtime = substream->private_data;
211 
212 	return snd_soc_dai_get_dma_data(soc_runtime->cpu_dai, substream);
213 }
214 
215 static void ringbuf_set_initial(void __iomem *audio_io,
216 		struct ringbuf_regs *p_rbuf,
217 		bool is_playback,
218 		u32 start,
219 		u32 periodsize,
220 		u32 bufsize)
221 {
222 	u32 initial_rd;
223 	u32 initial_wr;
224 	u32 end;
225 	u32 fmark_val; /* free or full mark */
226 
227 	p_rbuf->period_bytes = periodsize;
228 	p_rbuf->buf_size = bufsize;
229 
230 	if (is_playback) {
231 		/* Set the pointers to indicate full (flip uppermost bit) */
232 		initial_rd = start;
233 		initial_wr = initial_rd ^ BIT(31);
234 	} else {
235 		/* Set the pointers to indicate empty */
236 		initial_wr = start;
237 		initial_rd = initial_wr;
238 	}
239 
240 	end = start + bufsize - 1;
241 
242 	/*
243 	 * The interrupt will fire when free/full mark is *exceeded*
244 	 * The fmark value must be multiple of PERIOD_BYTES_MIN so set fmark
245 	 * to be PERIOD_BYTES_MIN less than the period size.
246 	 */
247 	fmark_val = periodsize - PERIOD_BYTES_MIN;
248 
249 	writel(start, audio_io + p_rbuf->baseaddr);
250 	writel(end, audio_io + p_rbuf->endaddr);
251 	writel(fmark_val, audio_io + p_rbuf->fmark);
252 	writel(initial_rd, audio_io + p_rbuf->rdaddr);
253 	writel(initial_wr, audio_io + p_rbuf->wraddr);
254 }
255 
256 static int configure_ringbuf_regs(struct snd_pcm_substream *substream)
257 {
258 	struct cygnus_aio_port *aio;
259 	struct ringbuf_regs *p_rbuf;
260 	int status = 0;
261 
262 	aio = cygnus_dai_get_dma_data(substream);
263 
264 	/* Map the ssp portnum to a set of ring buffers. */
265 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
266 		p_rbuf = &aio->play_rb_regs;
267 
268 		switch (aio->portnum) {
269 		case 0:
270 			*p_rbuf = RINGBUF_REG_PLAYBACK(0);
271 			break;
272 		case 1:
273 			*p_rbuf = RINGBUF_REG_PLAYBACK(2);
274 			break;
275 		case 2:
276 			*p_rbuf = RINGBUF_REG_PLAYBACK(4);
277 			break;
278 		case 3: /* SPDIF */
279 			*p_rbuf = RINGBUF_REG_PLAYBACK(6);
280 			break;
281 		default:
282 			status = -EINVAL;
283 		}
284 	} else {
285 		p_rbuf = &aio->capture_rb_regs;
286 
287 		switch (aio->portnum) {
288 		case 0:
289 			*p_rbuf = RINGBUF_REG_CAPTURE(0);
290 			break;
291 		case 1:
292 			*p_rbuf = RINGBUF_REG_CAPTURE(2);
293 			break;
294 		case 2:
295 			*p_rbuf = RINGBUF_REG_CAPTURE(4);
296 			break;
297 		default:
298 			status = -EINVAL;
299 		}
300 	}
301 
302 	return status;
303 }
304 
305 static struct ringbuf_regs *get_ringbuf(struct snd_pcm_substream *substream)
306 {
307 	struct cygnus_aio_port *aio;
308 	struct ringbuf_regs *p_rbuf = NULL;
309 
310 	aio = cygnus_dai_get_dma_data(substream);
311 
312 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
313 		p_rbuf = &aio->play_rb_regs;
314 	else
315 		p_rbuf = &aio->capture_rb_regs;
316 
317 	return p_rbuf;
318 }
319 
320 static void enable_intr(struct snd_pcm_substream *substream)
321 {
322 	struct cygnus_aio_port *aio;
323 	u32 clear_mask;
324 
325 	aio = cygnus_dai_get_dma_data(substream);
326 
327 	/* The port number maps to the bit position to be cleared */
328 	clear_mask = BIT(aio->portnum);
329 
330 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
331 		/* Clear interrupt status before enabling them */
332 		writel(clear_mask, aio->cygaud->audio + ESR0_STATUS_CLR_OFFSET);
333 		writel(clear_mask, aio->cygaud->audio + ESR1_STATUS_CLR_OFFSET);
334 		writel(clear_mask, aio->cygaud->audio + ESR3_STATUS_CLR_OFFSET);
335 		/* Unmask the interrupts of the given port*/
336 		writel(clear_mask, aio->cygaud->audio + ESR0_MASK_CLR_OFFSET);
337 		writel(clear_mask, aio->cygaud->audio + ESR1_MASK_CLR_OFFSET);
338 		writel(clear_mask, aio->cygaud->audio + ESR3_MASK_CLR_OFFSET);
339 
340 		writel(ANY_PLAYBACK_IRQ,
341 			aio->cygaud->audio + INTH_R5F_MASK_CLEAR_OFFSET);
342 	} else {
343 		writel(clear_mask, aio->cygaud->audio + ESR2_STATUS_CLR_OFFSET);
344 		writel(clear_mask, aio->cygaud->audio + ESR4_STATUS_CLR_OFFSET);
345 		writel(clear_mask, aio->cygaud->audio + ESR2_MASK_CLR_OFFSET);
346 		writel(clear_mask, aio->cygaud->audio + ESR4_MASK_CLR_OFFSET);
347 
348 		writel(ANY_CAPTURE_IRQ,
349 			aio->cygaud->audio + INTH_R5F_MASK_CLEAR_OFFSET);
350 	}
351 
352 }
353 
354 static void disable_intr(struct snd_pcm_substream *substream)
355 {
356 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
357 	struct cygnus_aio_port *aio;
358 	u32 set_mask;
359 
360 	aio = cygnus_dai_get_dma_data(substream);
361 
362 	dev_dbg(rtd->cpu_dai->dev, "%s on port %d\n", __func__, aio->portnum);
363 
364 	/* The port number maps to the bit position to be set */
365 	set_mask = BIT(aio->portnum);
366 
367 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
368 		/* Mask the interrupts of the given port*/
369 		writel(set_mask, aio->cygaud->audio + ESR0_MASK_SET_OFFSET);
370 		writel(set_mask, aio->cygaud->audio + ESR1_MASK_SET_OFFSET);
371 		writel(set_mask, aio->cygaud->audio + ESR3_MASK_SET_OFFSET);
372 	} else {
373 		writel(set_mask, aio->cygaud->audio + ESR2_MASK_SET_OFFSET);
374 		writel(set_mask, aio->cygaud->audio + ESR4_MASK_SET_OFFSET);
375 	}
376 
377 }
378 
379 static int cygnus_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
380 {
381 	int ret = 0;
382 
383 	switch (cmd) {
384 	case SNDRV_PCM_TRIGGER_START:
385 	case SNDRV_PCM_TRIGGER_RESUME:
386 		enable_intr(substream);
387 		break;
388 
389 	case SNDRV_PCM_TRIGGER_STOP:
390 	case SNDRV_PCM_TRIGGER_SUSPEND:
391 		disable_intr(substream);
392 		break;
393 	default:
394 		ret = -EINVAL;
395 	}
396 
397 	return ret;
398 }
399 
400 static void cygnus_pcm_period_elapsed(struct snd_pcm_substream *substream)
401 {
402 	struct cygnus_aio_port *aio;
403 	struct ringbuf_regs *p_rbuf = NULL;
404 	u32 regval;
405 
406 	aio = cygnus_dai_get_dma_data(substream);
407 
408 	p_rbuf = get_ringbuf(substream);
409 
410 	/*
411 	 * If free/full mark interrupt occurs, provide timestamp
412 	 * to ALSA and update appropriate idx by period_bytes
413 	 */
414 	snd_pcm_period_elapsed(substream);
415 
416 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
417 		/* Set the ring buffer to full */
418 		regval = readl(aio->cygaud->audio + p_rbuf->rdaddr);
419 		regval = regval ^ BIT(31);
420 		writel(regval, aio->cygaud->audio + p_rbuf->wraddr);
421 	} else {
422 		/* Set the ring buffer to empty */
423 		regval = readl(aio->cygaud->audio + p_rbuf->wraddr);
424 		writel(regval, aio->cygaud->audio + p_rbuf->rdaddr);
425 	}
426 }
427 
428 /*
429  * ESR0/1/3 status  Description
430  *  0x1	I2S0_out port caused interrupt
431  *  0x2	I2S1_out port caused interrupt
432  *  0x4	I2S2_out port caused interrupt
433  *  0x8	SPDIF_out port caused interrupt
434  */
435 static void handle_playback_irq(struct cygnus_audio *cygaud)
436 {
437 	void __iomem *audio_io;
438 	u32 port;
439 	u32 esr_status0, esr_status1, esr_status3;
440 
441 	audio_io = cygaud->audio;
442 
443 	/*
444 	 * ESR status gets updates with/without interrupts enabled.
445 	 * So, check the ESR mask, which provides interrupt enable/
446 	 * disable status and use it to determine which ESR status
447 	 * should be serviced.
448 	 */
449 	esr_status0 = readl(audio_io + ESR0_STATUS_OFFSET);
450 	esr_status0 &= ~readl(audio_io + ESR0_MASK_STATUS_OFFSET);
451 	esr_status1 = readl(audio_io + ESR1_STATUS_OFFSET);
452 	esr_status1 &= ~readl(audio_io + ESR1_MASK_STATUS_OFFSET);
453 	esr_status3 = readl(audio_io + ESR3_STATUS_OFFSET);
454 	esr_status3 &= ~readl(audio_io + ESR3_MASK_STATUS_OFFSET);
455 
456 	for (port = 0; port < CYGNUS_MAX_PLAYBACK_PORTS; port++) {
457 		u32 esrmask = BIT(port);
458 
459 		/*
460 		 * Ringbuffer or FIFO underflow
461 		 * If we get this interrupt then, it is also true that we have
462 		 * not yet responded to the freemark interrupt.
463 		 * Log a debug message.  The freemark handler below will
464 		 * handle getting everything going again.
465 		 */
466 		if ((esrmask & esr_status1) || (esrmask & esr_status0)) {
467 			dev_dbg(cygaud->dev,
468 				"Underrun: esr0=0x%x, esr1=0x%x esr3=0x%x\n",
469 				esr_status0, esr_status1, esr_status3);
470 		}
471 
472 		/*
473 		 * Freemark is hit. This is the normal interrupt.
474 		 * In typical operation the read and write regs will be equal
475 		 */
476 		if (esrmask & esr_status3) {
477 			struct snd_pcm_substream *playstr;
478 
479 			playstr = cygaud->portinfo[port].play_stream;
480 			cygnus_pcm_period_elapsed(playstr);
481 		}
482 	}
483 
484 	/* Clear ESR interrupt */
485 	writel(esr_status0, audio_io + ESR0_STATUS_CLR_OFFSET);
486 	writel(esr_status1, audio_io + ESR1_STATUS_CLR_OFFSET);
487 	writel(esr_status3, audio_io + ESR3_STATUS_CLR_OFFSET);
488 	/* Rearm freemark logic by writing 1 to the correct bit */
489 	writel(esr_status3, audio_io + BF_REARM_FREE_MARK_OFFSET);
490 }
491 
492 /*
493  * ESR2/4 status  Description
494  *  0x1	I2S0_in port caused interrupt
495  *  0x2	I2S1_in port caused interrupt
496  *  0x4	I2S2_in port caused interrupt
497  */
498 static void handle_capture_irq(struct cygnus_audio *cygaud)
499 {
500 	void __iomem *audio_io;
501 	u32 port;
502 	u32 esr_status2, esr_status4;
503 
504 	audio_io = cygaud->audio;
505 
506 	/*
507 	 * ESR status gets updates with/without interrupts enabled.
508 	 * So, check the ESR mask, which provides interrupt enable/
509 	 * disable status and use it to determine which ESR status
510 	 * should be serviced.
511 	 */
512 	esr_status2 = readl(audio_io + ESR2_STATUS_OFFSET);
513 	esr_status2 &= ~readl(audio_io + ESR2_MASK_STATUS_OFFSET);
514 	esr_status4 = readl(audio_io + ESR4_STATUS_OFFSET);
515 	esr_status4 &= ~readl(audio_io + ESR4_MASK_STATUS_OFFSET);
516 
517 	for (port = 0; port < CYGNUS_MAX_CAPTURE_PORTS; port++) {
518 		u32 esrmask = BIT(port);
519 
520 		/*
521 		 * Ringbuffer or FIFO overflow
522 		 * If we get this interrupt then, it is also true that we have
523 		 * not yet responded to the fullmark interrupt.
524 		 * Log a debug message.  The fullmark handler below will
525 		 * handle getting everything going again.
526 		 */
527 		if (esrmask & esr_status2)
528 			dev_dbg(cygaud->dev,
529 				"Overflow: esr2=0x%x\n", esr_status2);
530 
531 		if (esrmask & esr_status4) {
532 			struct snd_pcm_substream *capstr;
533 
534 			capstr = cygaud->portinfo[port].capture_stream;
535 			cygnus_pcm_period_elapsed(capstr);
536 		}
537 	}
538 
539 	writel(esr_status2, audio_io + ESR2_STATUS_CLR_OFFSET);
540 	writel(esr_status4, audio_io + ESR4_STATUS_CLR_OFFSET);
541 	/* Rearm fullmark logic by writing 1 to the correct bit */
542 	writel(esr_status4, audio_io + BF_REARM_FULL_MARK_OFFSET);
543 }
544 
545 static irqreturn_t cygnus_dma_irq(int irq, void *data)
546 {
547 	u32 r5_status;
548 	struct cygnus_audio *cygaud = data;
549 
550 	/*
551 	 * R5 status bits	Description
552 	 *  0		ESR0 (playback FIFO interrupt)
553 	 *  1		ESR1 (playback rbuf interrupt)
554 	 *  2		ESR2 (capture rbuf interrupt)
555 	 *  3		ESR3 (Freemark play. interrupt)
556 	 *  4		ESR4 (Fullmark capt. interrupt)
557 	 */
558 	r5_status = readl(cygaud->audio + INTH_R5F_STATUS_OFFSET);
559 
560 	if (!(r5_status & (ANY_PLAYBACK_IRQ | ANY_CAPTURE_IRQ)))
561 		return IRQ_NONE;
562 
563 	/* If playback interrupt happened */
564 	if (ANY_PLAYBACK_IRQ & r5_status) {
565 		handle_playback_irq(cygaud);
566 		writel(ANY_PLAYBACK_IRQ & r5_status,
567 			cygaud->audio + INTH_R5F_CLEAR_OFFSET);
568 	}
569 
570 	/* If  capture interrupt happened */
571 	if (ANY_CAPTURE_IRQ & r5_status) {
572 		handle_capture_irq(cygaud);
573 		writel(ANY_CAPTURE_IRQ & r5_status,
574 			cygaud->audio + INTH_R5F_CLEAR_OFFSET);
575 	}
576 
577 	return IRQ_HANDLED;
578 }
579 
580 static int cygnus_pcm_open(struct snd_pcm_substream *substream)
581 {
582 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
583 	struct snd_pcm_runtime *runtime = substream->runtime;
584 	struct cygnus_aio_port *aio;
585 	int ret;
586 
587 	aio = cygnus_dai_get_dma_data(substream);
588 	if (!aio)
589 		return -ENODEV;
590 
591 	dev_dbg(rtd->cpu_dai->dev, "%s port %d\n", __func__, aio->portnum);
592 
593 	snd_soc_set_runtime_hwparams(substream, &cygnus_pcm_hw);
594 
595 	ret = snd_pcm_hw_constraint_step(runtime, 0,
596 		SNDRV_PCM_HW_PARAM_PERIOD_BYTES, PERIOD_BYTES_MIN);
597 	if (ret < 0)
598 		return ret;
599 
600 	ret = snd_pcm_hw_constraint_step(runtime, 0,
601 		SNDRV_PCM_HW_PARAM_BUFFER_BYTES, PERIOD_BYTES_MIN);
602 	if (ret < 0)
603 		return ret;
604 	/*
605 	 * Keep track of which substream belongs to which port.
606 	 * This info is needed by snd_pcm_period_elapsed() in irq_handler
607 	 */
608 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
609 		aio->play_stream = substream;
610 	else
611 		aio->capture_stream = substream;
612 
613 	return 0;
614 }
615 
616 static int cygnus_pcm_close(struct snd_pcm_substream *substream)
617 {
618 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
619 	struct cygnus_aio_port *aio;
620 
621 	aio = cygnus_dai_get_dma_data(substream);
622 
623 	dev_dbg(rtd->cpu_dai->dev, "%s  port %d\n", __func__, aio->portnum);
624 
625 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
626 		aio->play_stream = NULL;
627 	else
628 		aio->capture_stream = NULL;
629 
630 	if (!aio->play_stream && !aio->capture_stream)
631 		dev_dbg(rtd->cpu_dai->dev, "freed  port %d\n", aio->portnum);
632 
633 	return 0;
634 }
635 
636 static int cygnus_pcm_hw_params(struct snd_pcm_substream *substream,
637 	struct snd_pcm_hw_params *params)
638 {
639 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
640 	struct snd_pcm_runtime *runtime = substream->runtime;
641 	struct cygnus_aio_port *aio;
642 	int ret = 0;
643 
644 	aio = cygnus_dai_get_dma_data(substream);
645 	dev_dbg(rtd->cpu_dai->dev, "%s  port %d\n", __func__, aio->portnum);
646 
647 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
648 	runtime->dma_bytes = params_buffer_bytes(params);
649 
650 	return ret;
651 }
652 
653 static int cygnus_pcm_hw_free(struct snd_pcm_substream *substream)
654 {
655 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
656 	struct cygnus_aio_port *aio;
657 
658 	aio = cygnus_dai_get_dma_data(substream);
659 	dev_dbg(rtd->cpu_dai->dev, "%s  port %d\n", __func__, aio->portnum);
660 
661 	snd_pcm_set_runtime_buffer(substream, NULL);
662 	return 0;
663 }
664 
665 static int cygnus_pcm_prepare(struct snd_pcm_substream *substream)
666 {
667 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
668 	struct snd_pcm_runtime *runtime = substream->runtime;
669 	struct cygnus_aio_port *aio;
670 	unsigned long bufsize, periodsize;
671 	int ret = 0;
672 	bool is_play;
673 	u32 start;
674 	struct ringbuf_regs *p_rbuf = NULL;
675 
676 	aio = cygnus_dai_get_dma_data(substream);
677 	dev_dbg(rtd->cpu_dai->dev, "%s port %d\n", __func__, aio->portnum);
678 
679 	bufsize = snd_pcm_lib_buffer_bytes(substream);
680 	periodsize = snd_pcm_lib_period_bytes(substream);
681 
682 	dev_dbg(rtd->cpu_dai->dev, "%s (buf_size %lu) (period_size %lu)\n",
683 			__func__, bufsize, periodsize);
684 
685 	configure_ringbuf_regs(substream);
686 
687 	p_rbuf = get_ringbuf(substream);
688 
689 	start = runtime->dma_addr;
690 
691 	is_play = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ? 1 : 0;
692 
693 	ringbuf_set_initial(aio->cygaud->audio, p_rbuf, is_play, start,
694 				periodsize, bufsize);
695 
696 	return ret;
697 }
698 
699 static snd_pcm_uframes_t cygnus_pcm_pointer(struct snd_pcm_substream *substream)
700 {
701 	struct cygnus_aio_port *aio;
702 	unsigned int res = 0, cur = 0, base = 0;
703 	struct ringbuf_regs *p_rbuf = NULL;
704 
705 	aio = cygnus_dai_get_dma_data(substream);
706 
707 	/*
708 	 * Get the offset of the current read (for playack) or write
709 	 * index (for capture).  Report this value back to the asoc framework.
710 	 */
711 	p_rbuf = get_ringbuf(substream);
712 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
713 		cur = readl(aio->cygaud->audio + p_rbuf->rdaddr);
714 	else
715 		cur = readl(aio->cygaud->audio + p_rbuf->wraddr);
716 
717 	base = readl(aio->cygaud->audio + p_rbuf->baseaddr);
718 
719 	/*
720 	 * Mask off the MSB of the rdaddr,wraddr and baseaddr
721 	 * since MSB is not part of the address
722 	 */
723 	res = (cur & 0x7fffffff) - (base & 0x7fffffff);
724 
725 	return bytes_to_frames(substream->runtime, res);
726 }
727 
728 static int cygnus_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
729 {
730 	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
731 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
732 	struct snd_dma_buffer *buf = &substream->dma_buffer;
733 	size_t size;
734 
735 	size = cygnus_pcm_hw.buffer_bytes_max;
736 
737 	buf->dev.type = SNDRV_DMA_TYPE_DEV;
738 	buf->dev.dev = pcm->card->dev;
739 	buf->private_data = NULL;
740 	buf->area = dma_alloc_coherent(pcm->card->dev, size,
741 			&buf->addr, GFP_KERNEL);
742 
743 	dev_dbg(rtd->cpu_dai->dev, "%s: size 0x%zx @ %pK\n",
744 				__func__, size, buf->area);
745 
746 	if (!buf->area) {
747 		dev_err(rtd->cpu_dai->dev, "%s: dma_alloc failed\n", __func__);
748 		return -ENOMEM;
749 	}
750 	buf->bytes = size;
751 
752 	return 0;
753 }
754 
755 
756 static const struct snd_pcm_ops cygnus_pcm_ops = {
757 	.open		= cygnus_pcm_open,
758 	.close		= cygnus_pcm_close,
759 	.ioctl		= snd_pcm_lib_ioctl,
760 	.hw_params	= cygnus_pcm_hw_params,
761 	.hw_free	= cygnus_pcm_hw_free,
762 	.prepare	= cygnus_pcm_prepare,
763 	.trigger	= cygnus_pcm_trigger,
764 	.pointer	= cygnus_pcm_pointer,
765 };
766 
767 static void cygnus_dma_free_dma_buffers(struct snd_pcm *pcm)
768 {
769 	struct snd_pcm_substream *substream;
770 	struct snd_dma_buffer *buf;
771 
772 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
773 	if (substream) {
774 		buf = &substream->dma_buffer;
775 		if (buf->area) {
776 			dma_free_coherent(pcm->card->dev, buf->bytes,
777 				buf->area, buf->addr);
778 			buf->area = NULL;
779 		}
780 	}
781 
782 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
783 	if (substream) {
784 		buf = &substream->dma_buffer;
785 		if (buf->area) {
786 			dma_free_coherent(pcm->card->dev, buf->bytes,
787 				buf->area, buf->addr);
788 			buf->area = NULL;
789 		}
790 	}
791 }
792 
793 static int cygnus_dma_new(struct snd_soc_pcm_runtime *rtd)
794 {
795 	struct snd_card *card = rtd->card->snd_card;
796 	struct snd_pcm *pcm = rtd->pcm;
797 	int ret;
798 
799 	if (!card->dev->dma_mask)
800 		card->dev->dma_mask = &cygnus_dma_dmamask;
801 	if (!card->dev->coherent_dma_mask)
802 		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
803 
804 	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
805 		ret = cygnus_pcm_preallocate_dma_buffer(pcm,
806 				SNDRV_PCM_STREAM_PLAYBACK);
807 		if (ret)
808 			return ret;
809 	}
810 
811 	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
812 		ret = cygnus_pcm_preallocate_dma_buffer(pcm,
813 				SNDRV_PCM_STREAM_CAPTURE);
814 		if (ret) {
815 			cygnus_dma_free_dma_buffers(pcm);
816 			return ret;
817 		}
818 	}
819 
820 	return 0;
821 }
822 
823 static struct snd_soc_component_driver cygnus_soc_platform = {
824 	.ops		= &cygnus_pcm_ops,
825 	.pcm_new	= cygnus_dma_new,
826 	.pcm_free	= cygnus_dma_free_dma_buffers,
827 };
828 
829 int cygnus_soc_platform_register(struct device *dev,
830 				 struct cygnus_audio *cygaud)
831 {
832 	int rc = 0;
833 
834 	dev_dbg(dev, "%s Enter\n", __func__);
835 
836 	rc = devm_request_irq(dev, cygaud->irq_num, cygnus_dma_irq,
837 				IRQF_SHARED, "cygnus-audio", cygaud);
838 	if (rc) {
839 		dev_err(dev, "%s request_irq error %d\n", __func__, rc);
840 		return rc;
841 	}
842 
843 	rc = devm_snd_soc_register_component(dev, &cygnus_soc_platform,
844 					     NULL, 0);
845 	if (rc) {
846 		dev_err(dev, "%s failed\n", __func__);
847 		return rc;
848 	}
849 
850 	return 0;
851 }
852 
853 int cygnus_soc_platform_unregister(struct device *dev)
854 {
855 	return 0;
856 }
857 
858 MODULE_LICENSE("GPL v2");
859 MODULE_AUTHOR("Broadcom");
860 MODULE_DESCRIPTION("Cygnus ASoC PCM module");
861