xref: /linux/sound/soc/bcm/cygnus-pcm.c (revision ca853314e78b0a65c20b6a889a23c31f918d4aa2)
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 = asoc_substream_to_rtd(substream);
211 
212 	return snd_soc_dai_get_dma_data(asoc_rtd_to_cpu(soc_runtime, 0), 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 = asoc_substream_to_rtd(substream);
357 	struct cygnus_aio_port *aio;
358 	u32 set_mask;
359 
360 	aio = cygnus_dai_get_dma_data(substream);
361 
362 	dev_dbg(asoc_rtd_to_cpu(rtd, 0)->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_soc_component *component,
380 			      struct snd_pcm_substream *substream, int cmd)
381 {
382 	int ret = 0;
383 
384 	switch (cmd) {
385 	case SNDRV_PCM_TRIGGER_START:
386 	case SNDRV_PCM_TRIGGER_RESUME:
387 		enable_intr(substream);
388 		break;
389 
390 	case SNDRV_PCM_TRIGGER_STOP:
391 	case SNDRV_PCM_TRIGGER_SUSPEND:
392 		disable_intr(substream);
393 		break;
394 	default:
395 		ret = -EINVAL;
396 	}
397 
398 	return ret;
399 }
400 
401 static void cygnus_pcm_period_elapsed(struct snd_pcm_substream *substream)
402 {
403 	struct cygnus_aio_port *aio;
404 	struct ringbuf_regs *p_rbuf = NULL;
405 	u32 regval;
406 
407 	aio = cygnus_dai_get_dma_data(substream);
408 
409 	p_rbuf = get_ringbuf(substream);
410 
411 	/*
412 	 * If free/full mark interrupt occurs, provide timestamp
413 	 * to ALSA and update appropriate idx by period_bytes
414 	 */
415 	snd_pcm_period_elapsed(substream);
416 
417 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) {
418 		/* Set the ring buffer to full */
419 		regval = readl(aio->cygaud->audio + p_rbuf->rdaddr);
420 		regval = regval ^ BIT(31);
421 		writel(regval, aio->cygaud->audio + p_rbuf->wraddr);
422 	} else {
423 		/* Set the ring buffer to empty */
424 		regval = readl(aio->cygaud->audio + p_rbuf->wraddr);
425 		writel(regval, aio->cygaud->audio + p_rbuf->rdaddr);
426 	}
427 }
428 
429 /*
430  * ESR0/1/3 status  Description
431  *  0x1	I2S0_out port caused interrupt
432  *  0x2	I2S1_out port caused interrupt
433  *  0x4	I2S2_out port caused interrupt
434  *  0x8	SPDIF_out port caused interrupt
435  */
436 static void handle_playback_irq(struct cygnus_audio *cygaud)
437 {
438 	void __iomem *audio_io;
439 	u32 port;
440 	u32 esr_status0, esr_status1, esr_status3;
441 
442 	audio_io = cygaud->audio;
443 
444 	/*
445 	 * ESR status gets updates with/without interrupts enabled.
446 	 * So, check the ESR mask, which provides interrupt enable/
447 	 * disable status and use it to determine which ESR status
448 	 * should be serviced.
449 	 */
450 	esr_status0 = readl(audio_io + ESR0_STATUS_OFFSET);
451 	esr_status0 &= ~readl(audio_io + ESR0_MASK_STATUS_OFFSET);
452 	esr_status1 = readl(audio_io + ESR1_STATUS_OFFSET);
453 	esr_status1 &= ~readl(audio_io + ESR1_MASK_STATUS_OFFSET);
454 	esr_status3 = readl(audio_io + ESR3_STATUS_OFFSET);
455 	esr_status3 &= ~readl(audio_io + ESR3_MASK_STATUS_OFFSET);
456 
457 	for (port = 0; port < CYGNUS_MAX_PLAYBACK_PORTS; port++) {
458 		u32 esrmask = BIT(port);
459 
460 		/*
461 		 * Ringbuffer or FIFO underflow
462 		 * If we get this interrupt then, it is also true that we have
463 		 * not yet responded to the freemark interrupt.
464 		 * Log a debug message.  The freemark handler below will
465 		 * handle getting everything going again.
466 		 */
467 		if ((esrmask & esr_status1) || (esrmask & esr_status0)) {
468 			dev_dbg(cygaud->dev,
469 				"Underrun: esr0=0x%x, esr1=0x%x esr3=0x%x\n",
470 				esr_status0, esr_status1, esr_status3);
471 		}
472 
473 		/*
474 		 * Freemark is hit. This is the normal interrupt.
475 		 * In typical operation the read and write regs will be equal
476 		 */
477 		if (esrmask & esr_status3) {
478 			struct snd_pcm_substream *playstr;
479 
480 			playstr = cygaud->portinfo[port].play_stream;
481 			cygnus_pcm_period_elapsed(playstr);
482 		}
483 	}
484 
485 	/* Clear ESR interrupt */
486 	writel(esr_status0, audio_io + ESR0_STATUS_CLR_OFFSET);
487 	writel(esr_status1, audio_io + ESR1_STATUS_CLR_OFFSET);
488 	writel(esr_status3, audio_io + ESR3_STATUS_CLR_OFFSET);
489 	/* Rearm freemark logic by writing 1 to the correct bit */
490 	writel(esr_status3, audio_io + BF_REARM_FREE_MARK_OFFSET);
491 }
492 
493 /*
494  * ESR2/4 status  Description
495  *  0x1	I2S0_in port caused interrupt
496  *  0x2	I2S1_in port caused interrupt
497  *  0x4	I2S2_in port caused interrupt
498  */
499 static void handle_capture_irq(struct cygnus_audio *cygaud)
500 {
501 	void __iomem *audio_io;
502 	u32 port;
503 	u32 esr_status2, esr_status4;
504 
505 	audio_io = cygaud->audio;
506 
507 	/*
508 	 * ESR status gets updates with/without interrupts enabled.
509 	 * So, check the ESR mask, which provides interrupt enable/
510 	 * disable status and use it to determine which ESR status
511 	 * should be serviced.
512 	 */
513 	esr_status2 = readl(audio_io + ESR2_STATUS_OFFSET);
514 	esr_status2 &= ~readl(audio_io + ESR2_MASK_STATUS_OFFSET);
515 	esr_status4 = readl(audio_io + ESR4_STATUS_OFFSET);
516 	esr_status4 &= ~readl(audio_io + ESR4_MASK_STATUS_OFFSET);
517 
518 	for (port = 0; port < CYGNUS_MAX_CAPTURE_PORTS; port++) {
519 		u32 esrmask = BIT(port);
520 
521 		/*
522 		 * Ringbuffer or FIFO overflow
523 		 * If we get this interrupt then, it is also true that we have
524 		 * not yet responded to the fullmark interrupt.
525 		 * Log a debug message.  The fullmark handler below will
526 		 * handle getting everything going again.
527 		 */
528 		if (esrmask & esr_status2)
529 			dev_dbg(cygaud->dev,
530 				"Overflow: esr2=0x%x\n", esr_status2);
531 
532 		if (esrmask & esr_status4) {
533 			struct snd_pcm_substream *capstr;
534 
535 			capstr = cygaud->portinfo[port].capture_stream;
536 			cygnus_pcm_period_elapsed(capstr);
537 		}
538 	}
539 
540 	writel(esr_status2, audio_io + ESR2_STATUS_CLR_OFFSET);
541 	writel(esr_status4, audio_io + ESR4_STATUS_CLR_OFFSET);
542 	/* Rearm fullmark logic by writing 1 to the correct bit */
543 	writel(esr_status4, audio_io + BF_REARM_FULL_MARK_OFFSET);
544 }
545 
546 static irqreturn_t cygnus_dma_irq(int irq, void *data)
547 {
548 	u32 r5_status;
549 	struct cygnus_audio *cygaud = data;
550 
551 	/*
552 	 * R5 status bits	Description
553 	 *  0		ESR0 (playback FIFO interrupt)
554 	 *  1		ESR1 (playback rbuf interrupt)
555 	 *  2		ESR2 (capture rbuf interrupt)
556 	 *  3		ESR3 (Freemark play. interrupt)
557 	 *  4		ESR4 (Fullmark capt. interrupt)
558 	 */
559 	r5_status = readl(cygaud->audio + INTH_R5F_STATUS_OFFSET);
560 
561 	if (!(r5_status & (ANY_PLAYBACK_IRQ | ANY_CAPTURE_IRQ)))
562 		return IRQ_NONE;
563 
564 	/* If playback interrupt happened */
565 	if (ANY_PLAYBACK_IRQ & r5_status) {
566 		handle_playback_irq(cygaud);
567 		writel(ANY_PLAYBACK_IRQ & r5_status,
568 			cygaud->audio + INTH_R5F_CLEAR_OFFSET);
569 	}
570 
571 	/* If  capture interrupt happened */
572 	if (ANY_CAPTURE_IRQ & r5_status) {
573 		handle_capture_irq(cygaud);
574 		writel(ANY_CAPTURE_IRQ & r5_status,
575 			cygaud->audio + INTH_R5F_CLEAR_OFFSET);
576 	}
577 
578 	return IRQ_HANDLED;
579 }
580 
581 static int cygnus_pcm_open(struct snd_soc_component *component,
582 			   struct snd_pcm_substream *substream)
583 {
584 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
585 	struct snd_pcm_runtime *runtime = substream->runtime;
586 	struct cygnus_aio_port *aio;
587 	int ret;
588 
589 	aio = cygnus_dai_get_dma_data(substream);
590 	if (!aio)
591 		return -ENODEV;
592 
593 	dev_dbg(asoc_rtd_to_cpu(rtd, 0)->dev, "%s port %d\n", __func__, aio->portnum);
594 
595 	snd_soc_set_runtime_hwparams(substream, &cygnus_pcm_hw);
596 
597 	ret = snd_pcm_hw_constraint_step(runtime, 0,
598 		SNDRV_PCM_HW_PARAM_PERIOD_BYTES, PERIOD_BYTES_MIN);
599 	if (ret < 0)
600 		return ret;
601 
602 	ret = snd_pcm_hw_constraint_step(runtime, 0,
603 		SNDRV_PCM_HW_PARAM_BUFFER_BYTES, PERIOD_BYTES_MIN);
604 	if (ret < 0)
605 		return ret;
606 	/*
607 	 * Keep track of which substream belongs to which port.
608 	 * This info is needed by snd_pcm_period_elapsed() in irq_handler
609 	 */
610 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
611 		aio->play_stream = substream;
612 	else
613 		aio->capture_stream = substream;
614 
615 	return 0;
616 }
617 
618 static int cygnus_pcm_close(struct snd_soc_component *component,
619 			    struct snd_pcm_substream *substream)
620 {
621 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
622 	struct cygnus_aio_port *aio;
623 
624 	aio = cygnus_dai_get_dma_data(substream);
625 
626 	dev_dbg(asoc_rtd_to_cpu(rtd, 0)->dev, "%s  port %d\n", __func__, aio->portnum);
627 
628 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
629 		aio->play_stream = NULL;
630 	else
631 		aio->capture_stream = NULL;
632 
633 	if (!aio->play_stream && !aio->capture_stream)
634 		dev_dbg(asoc_rtd_to_cpu(rtd, 0)->dev, "freed  port %d\n", aio->portnum);
635 
636 	return 0;
637 }
638 
639 static int cygnus_pcm_hw_params(struct snd_soc_component *component,
640 				struct snd_pcm_substream *substream,
641 				struct snd_pcm_hw_params *params)
642 {
643 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
644 	struct snd_pcm_runtime *runtime = substream->runtime;
645 	struct cygnus_aio_port *aio;
646 
647 	aio = cygnus_dai_get_dma_data(substream);
648 	dev_dbg(asoc_rtd_to_cpu(rtd, 0)->dev, "%s  port %d\n", __func__, aio->portnum);
649 
650 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
651 	runtime->dma_bytes = params_buffer_bytes(params);
652 
653 	return 0;
654 }
655 
656 static int cygnus_pcm_hw_free(struct snd_soc_component *component,
657 			      struct snd_pcm_substream *substream)
658 {
659 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
660 	struct cygnus_aio_port *aio;
661 
662 	aio = cygnus_dai_get_dma_data(substream);
663 	dev_dbg(asoc_rtd_to_cpu(rtd, 0)->dev, "%s  port %d\n", __func__, aio->portnum);
664 
665 	snd_pcm_set_runtime_buffer(substream, NULL);
666 	return 0;
667 }
668 
669 static int cygnus_pcm_prepare(struct snd_soc_component *component,
670 			      struct snd_pcm_substream *substream)
671 {
672 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
673 	struct snd_pcm_runtime *runtime = substream->runtime;
674 	struct cygnus_aio_port *aio;
675 	unsigned long bufsize, periodsize;
676 	bool is_play;
677 	u32 start;
678 	struct ringbuf_regs *p_rbuf = NULL;
679 
680 	aio = cygnus_dai_get_dma_data(substream);
681 	dev_dbg(asoc_rtd_to_cpu(rtd, 0)->dev, "%s port %d\n", __func__, aio->portnum);
682 
683 	bufsize = snd_pcm_lib_buffer_bytes(substream);
684 	periodsize = snd_pcm_lib_period_bytes(substream);
685 
686 	dev_dbg(asoc_rtd_to_cpu(rtd, 0)->dev, "%s (buf_size %lu) (period_size %lu)\n",
687 			__func__, bufsize, periodsize);
688 
689 	configure_ringbuf_regs(substream);
690 
691 	p_rbuf = get_ringbuf(substream);
692 
693 	start = runtime->dma_addr;
694 
695 	is_play = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ? 1 : 0;
696 
697 	ringbuf_set_initial(aio->cygaud->audio, p_rbuf, is_play, start,
698 				periodsize, bufsize);
699 
700 	return 0;
701 }
702 
703 static snd_pcm_uframes_t cygnus_pcm_pointer(struct snd_soc_component *component,
704 					    struct snd_pcm_substream *substream)
705 {
706 	struct cygnus_aio_port *aio;
707 	unsigned int res = 0, cur = 0, base = 0;
708 	struct ringbuf_regs *p_rbuf = NULL;
709 
710 	aio = cygnus_dai_get_dma_data(substream);
711 
712 	/*
713 	 * Get the offset of the current read (for playack) or write
714 	 * index (for capture).  Report this value back to the asoc framework.
715 	 */
716 	p_rbuf = get_ringbuf(substream);
717 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
718 		cur = readl(aio->cygaud->audio + p_rbuf->rdaddr);
719 	else
720 		cur = readl(aio->cygaud->audio + p_rbuf->wraddr);
721 
722 	base = readl(aio->cygaud->audio + p_rbuf->baseaddr);
723 
724 	/*
725 	 * Mask off the MSB of the rdaddr,wraddr and baseaddr
726 	 * since MSB is not part of the address
727 	 */
728 	res = (cur & 0x7fffffff) - (base & 0x7fffffff);
729 
730 	return bytes_to_frames(substream->runtime, res);
731 }
732 
733 static int cygnus_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
734 {
735 	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
736 	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
737 	struct snd_dma_buffer *buf = &substream->dma_buffer;
738 	size_t size;
739 
740 	size = cygnus_pcm_hw.buffer_bytes_max;
741 
742 	buf->dev.type = SNDRV_DMA_TYPE_DEV;
743 	buf->dev.dev = pcm->card->dev;
744 	buf->private_data = NULL;
745 	buf->area = dma_alloc_coherent(pcm->card->dev, size,
746 			&buf->addr, GFP_KERNEL);
747 
748 	dev_dbg(asoc_rtd_to_cpu(rtd, 0)->dev, "%s: size 0x%zx @ %pK\n",
749 				__func__, size, buf->area);
750 
751 	if (!buf->area) {
752 		dev_err(asoc_rtd_to_cpu(rtd, 0)->dev, "%s: dma_alloc failed\n", __func__);
753 		return -ENOMEM;
754 	}
755 	buf->bytes = size;
756 
757 	return 0;
758 }
759 
760 static void cygnus_dma_free_dma_buffers(struct snd_soc_component *component,
761 					struct snd_pcm *pcm)
762 {
763 	struct snd_pcm_substream *substream;
764 	struct snd_dma_buffer *buf;
765 
766 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
767 	if (substream) {
768 		buf = &substream->dma_buffer;
769 		if (buf->area) {
770 			dma_free_coherent(pcm->card->dev, buf->bytes,
771 				buf->area, buf->addr);
772 			buf->area = NULL;
773 		}
774 	}
775 
776 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
777 	if (substream) {
778 		buf = &substream->dma_buffer;
779 		if (buf->area) {
780 			dma_free_coherent(pcm->card->dev, buf->bytes,
781 				buf->area, buf->addr);
782 			buf->area = NULL;
783 		}
784 	}
785 }
786 
787 static int cygnus_dma_new(struct snd_soc_component *component,
788 			  struct snd_soc_pcm_runtime *rtd)
789 {
790 	struct snd_card *card = rtd->card->snd_card;
791 	struct snd_pcm *pcm = rtd->pcm;
792 	int ret;
793 
794 	if (!card->dev->dma_mask)
795 		card->dev->dma_mask = &cygnus_dma_dmamask;
796 	if (!card->dev->coherent_dma_mask)
797 		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
798 
799 	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
800 		ret = cygnus_pcm_preallocate_dma_buffer(pcm,
801 				SNDRV_PCM_STREAM_PLAYBACK);
802 		if (ret)
803 			return ret;
804 	}
805 
806 	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
807 		ret = cygnus_pcm_preallocate_dma_buffer(pcm,
808 				SNDRV_PCM_STREAM_CAPTURE);
809 		if (ret) {
810 			cygnus_dma_free_dma_buffers(component, pcm);
811 			return ret;
812 		}
813 	}
814 
815 	return 0;
816 }
817 
818 static struct snd_soc_component_driver cygnus_soc_platform = {
819 	.open		= cygnus_pcm_open,
820 	.close		= cygnus_pcm_close,
821 	.hw_params	= cygnus_pcm_hw_params,
822 	.hw_free	= cygnus_pcm_hw_free,
823 	.prepare	= cygnus_pcm_prepare,
824 	.trigger	= cygnus_pcm_trigger,
825 	.pointer	= cygnus_pcm_pointer,
826 	.pcm_construct	= cygnus_dma_new,
827 	.pcm_destruct	= cygnus_dma_free_dma_buffers,
828 };
829 
830 int cygnus_soc_platform_register(struct device *dev,
831 				 struct cygnus_audio *cygaud)
832 {
833 	int rc = 0;
834 
835 	dev_dbg(dev, "%s Enter\n", __func__);
836 
837 	rc = devm_request_irq(dev, cygaud->irq_num, cygnus_dma_irq,
838 				IRQF_SHARED, "cygnus-audio", cygaud);
839 	if (rc) {
840 		dev_err(dev, "%s request_irq error %d\n", __func__, rc);
841 		return rc;
842 	}
843 
844 	rc = devm_snd_soc_register_component(dev, &cygnus_soc_platform,
845 					     NULL, 0);
846 	if (rc) {
847 		dev_err(dev, "%s failed\n", __func__);
848 		return rc;
849 	}
850 
851 	return 0;
852 }
853 
854 int cygnus_soc_platform_unregister(struct device *dev)
855 {
856 	return 0;
857 }
858 
859 MODULE_LICENSE("GPL v2");
860 MODULE_AUTHOR("Broadcom");
861 MODULE_DESCRIPTION("Cygnus ASoC PCM module");
862