1// SPDX-License-Identifier: GPL-2.0+
2// imx-pcm-fiq.c  --  ALSA Soc Audio Layer
3//
4// Copyright 2009 Sascha Hauer <s.hauer@pengutronix.de>
5//
6// This code is based on code copyrighted by Freescale,
7// Liam Girdwood, Javier Martin and probably others.
8
9#include <linux/clk.h>
10#include <linux/delay.h>
11#include <linux/device.h>
12#include <linux/dma-mapping.h>
13#include <linux/init.h>
14#include <linux/interrupt.h>
15#include <linux/module.h>
16#include <linux/platform_device.h>
17#include <linux/slab.h>
18
19#include <sound/core.h>
20#include <sound/dmaengine_pcm.h>
21#include <sound/initval.h>
22#include <sound/pcm.h>
23#include <sound/pcm_params.h>
24#include <sound/soc.h>
25
26#include <asm/fiq.h>
27
28#include <linux/platform_data/asoc-imx-ssi.h>
29
30#include "imx-ssi.h"
31#include "imx-pcm.h"
32
33struct imx_pcm_runtime_data {
34	unsigned int period;
35	int periods;
36	unsigned long offset;
37	struct hrtimer hrt;
38	int poll_time_ns;
39	struct snd_pcm_substream *substream;
40	atomic_t playing;
41	atomic_t capturing;
42};
43
44static enum hrtimer_restart snd_hrtimer_callback(struct hrtimer *hrt)
45{
46	struct imx_pcm_runtime_data *iprtd =
47		container_of(hrt, struct imx_pcm_runtime_data, hrt);
48	struct snd_pcm_substream *substream = iprtd->substream;
49	struct pt_regs regs;
50
51	if (!atomic_read(&iprtd->playing) && !atomic_read(&iprtd->capturing))
52		return HRTIMER_NORESTART;
53
54	get_fiq_regs(&regs);
55
56	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
57		iprtd->offset = regs.ARM_r8 & 0xffff;
58	else
59		iprtd->offset = regs.ARM_r9 & 0xffff;
60
61	snd_pcm_period_elapsed(substream);
62
63	hrtimer_forward_now(hrt, ns_to_ktime(iprtd->poll_time_ns));
64
65	return HRTIMER_RESTART;
66}
67
68static struct fiq_handler fh = {
69	.name		= DRV_NAME,
70};
71
72static int snd_imx_pcm_hw_params(struct snd_soc_component *component,
73				 struct snd_pcm_substream *substream,
74				 struct snd_pcm_hw_params *params)
75{
76	struct snd_pcm_runtime *runtime = substream->runtime;
77	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
78
79	iprtd->periods = params_periods(params);
80	iprtd->period = params_period_bytes(params);
81	iprtd->offset = 0;
82	iprtd->poll_time_ns = 1000000000 / params_rate(params) *
83				params_period_size(params);
84	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
85
86	return 0;
87}
88
89static int snd_imx_pcm_prepare(struct snd_soc_component *component,
90			       struct snd_pcm_substream *substream)
91{
92	struct snd_pcm_runtime *runtime = substream->runtime;
93	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
94	struct pt_regs regs;
95
96	get_fiq_regs(&regs);
97	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
98		regs.ARM_r8 = (iprtd->period * iprtd->periods - 1) << 16;
99	else
100		regs.ARM_r9 = (iprtd->period * iprtd->periods - 1) << 16;
101
102	set_fiq_regs(&regs);
103
104	return 0;
105}
106
107static int imx_pcm_fiq;
108
109static int snd_imx_pcm_trigger(struct snd_soc_component *component,
110			       struct snd_pcm_substream *substream, int cmd)
111{
112	struct snd_pcm_runtime *runtime = substream->runtime;
113	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
114
115	switch (cmd) {
116	case SNDRV_PCM_TRIGGER_START:
117	case SNDRV_PCM_TRIGGER_RESUME:
118	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
119		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
120			atomic_set(&iprtd->playing, 1);
121		else
122			atomic_set(&iprtd->capturing, 1);
123		hrtimer_start(&iprtd->hrt, ns_to_ktime(iprtd->poll_time_ns),
124		      HRTIMER_MODE_REL);
125		enable_fiq(imx_pcm_fiq);
126		break;
127
128	case SNDRV_PCM_TRIGGER_STOP:
129	case SNDRV_PCM_TRIGGER_SUSPEND:
130	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
131		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
132			atomic_set(&iprtd->playing, 0);
133		else
134			atomic_set(&iprtd->capturing, 0);
135		if (!atomic_read(&iprtd->playing) &&
136				!atomic_read(&iprtd->capturing))
137			disable_fiq(imx_pcm_fiq);
138		break;
139
140	default:
141		return -EINVAL;
142	}
143
144	return 0;
145}
146
147static snd_pcm_uframes_t
148snd_imx_pcm_pointer(struct snd_soc_component *component,
149		    struct snd_pcm_substream *substream)
150{
151	struct snd_pcm_runtime *runtime = substream->runtime;
152	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
153
154	return bytes_to_frames(substream->runtime, iprtd->offset);
155}
156
157static const struct snd_pcm_hardware snd_imx_hardware = {
158	.info = SNDRV_PCM_INFO_INTERLEAVED |
159		SNDRV_PCM_INFO_BLOCK_TRANSFER |
160		SNDRV_PCM_INFO_MMAP |
161		SNDRV_PCM_INFO_MMAP_VALID |
162		SNDRV_PCM_INFO_PAUSE |
163		SNDRV_PCM_INFO_RESUME,
164	.formats = SNDRV_PCM_FMTBIT_S16_LE,
165	.buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
166	.period_bytes_min = 128,
167	.period_bytes_max = 16 * 1024,
168	.periods_min = 4,
169	.periods_max = 255,
170	.fifo_size = 0,
171};
172
173static int snd_imx_open(struct snd_soc_component *component,
174			struct snd_pcm_substream *substream)
175{
176	struct snd_pcm_runtime *runtime = substream->runtime;
177	struct imx_pcm_runtime_data *iprtd;
178	int ret;
179
180	iprtd = kzalloc(sizeof(*iprtd), GFP_KERNEL);
181	if (iprtd == NULL)
182		return -ENOMEM;
183	runtime->private_data = iprtd;
184
185	iprtd->substream = substream;
186
187	atomic_set(&iprtd->playing, 0);
188	atomic_set(&iprtd->capturing, 0);
189	hrtimer_init(&iprtd->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
190	iprtd->hrt.function = snd_hrtimer_callback;
191
192	ret = snd_pcm_hw_constraint_integer(substream->runtime,
193			SNDRV_PCM_HW_PARAM_PERIODS);
194	if (ret < 0) {
195		kfree(iprtd);
196		return ret;
197	}
198
199	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
200	return 0;
201}
202
203static int snd_imx_close(struct snd_soc_component *component,
204			 struct snd_pcm_substream *substream)
205{
206	struct snd_pcm_runtime *runtime = substream->runtime;
207	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
208
209	hrtimer_cancel(&iprtd->hrt);
210
211	kfree(iprtd);
212
213	return 0;
214}
215
216static int snd_imx_pcm_mmap(struct snd_soc_component *component,
217			    struct snd_pcm_substream *substream,
218			    struct vm_area_struct *vma)
219{
220	struct snd_pcm_runtime *runtime = substream->runtime;
221	int ret;
222
223	ret = dma_mmap_wc(substream->pcm->card->dev, vma, runtime->dma_area,
224			  runtime->dma_addr, runtime->dma_bytes);
225
226	pr_debug("%s: ret: %d %p %pad 0x%08zx\n", __func__, ret,
227			runtime->dma_area,
228			&runtime->dma_addr,
229			runtime->dma_bytes);
230	return ret;
231}
232
233static int imx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
234{
235	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
236	struct snd_dma_buffer *buf = &substream->dma_buffer;
237	size_t size = IMX_SSI_DMABUF_SIZE;
238
239	buf->dev.type = SNDRV_DMA_TYPE_DEV;
240	buf->dev.dev = pcm->card->dev;
241	buf->private_data = NULL;
242	buf->area = dma_alloc_wc(pcm->card->dev, size, &buf->addr, GFP_KERNEL);
243	if (!buf->area)
244		return -ENOMEM;
245	buf->bytes = size;
246
247	return 0;
248}
249
250static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
251{
252	struct snd_card *card = rtd->card->snd_card;
253	struct snd_pcm *pcm = rtd->pcm;
254	int ret;
255
256	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
257	if (ret)
258		return ret;
259
260	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
261		ret = imx_pcm_preallocate_dma_buffer(pcm,
262			SNDRV_PCM_STREAM_PLAYBACK);
263		if (ret)
264			return ret;
265	}
266
267	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
268		ret = imx_pcm_preallocate_dma_buffer(pcm,
269			SNDRV_PCM_STREAM_CAPTURE);
270		if (ret)
271			return ret;
272	}
273
274	return 0;
275}
276
277static int ssi_irq;
278
279static int snd_imx_pcm_new(struct snd_soc_component *component,
280			   struct snd_soc_pcm_runtime *rtd)
281{
282	struct snd_pcm *pcm = rtd->pcm;
283	struct snd_pcm_substream *substream;
284	int ret;
285
286	ret = imx_pcm_new(rtd);
287	if (ret)
288		return ret;
289
290	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
291	if (substream) {
292		struct snd_dma_buffer *buf = &substream->dma_buffer;
293
294		imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
295	}
296
297	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
298	if (substream) {
299		struct snd_dma_buffer *buf = &substream->dma_buffer;
300
301		imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
302	}
303
304	set_fiq_handler(&imx_ssi_fiq_start,
305		&imx_ssi_fiq_end - &imx_ssi_fiq_start);
306
307	return 0;
308}
309
310static void imx_pcm_free(struct snd_pcm *pcm)
311{
312	struct snd_pcm_substream *substream;
313	struct snd_dma_buffer *buf;
314	int stream;
315
316	for (stream = 0; stream < 2; stream++) {
317		substream = pcm->streams[stream].substream;
318		if (!substream)
319			continue;
320
321		buf = &substream->dma_buffer;
322		if (!buf->area)
323			continue;
324
325		dma_free_wc(pcm->card->dev, buf->bytes, buf->area, buf->addr);
326		buf->area = NULL;
327	}
328}
329
330static void snd_imx_pcm_free(struct snd_soc_component *component,
331			     struct snd_pcm *pcm)
332{
333	mxc_set_irq_fiq(ssi_irq, 0);
334	release_fiq(&fh);
335	imx_pcm_free(pcm);
336}
337
338static const struct snd_soc_component_driver imx_soc_component_fiq = {
339	.open		= snd_imx_open,
340	.close		= snd_imx_close,
341	.hw_params	= snd_imx_pcm_hw_params,
342	.prepare	= snd_imx_pcm_prepare,
343	.trigger	= snd_imx_pcm_trigger,
344	.pointer	= snd_imx_pcm_pointer,
345	.mmap		= snd_imx_pcm_mmap,
346	.pcm_construct	= snd_imx_pcm_new,
347	.pcm_destruct	= snd_imx_pcm_free,
348};
349
350int imx_pcm_fiq_init(struct platform_device *pdev,
351		struct imx_pcm_fiq_params *params)
352{
353	int ret;
354
355	ret = claim_fiq(&fh);
356	if (ret) {
357		dev_err(&pdev->dev, "failed to claim fiq: %d", ret);
358		return ret;
359	}
360
361	mxc_set_irq_fiq(params->irq, 1);
362	ssi_irq = params->irq;
363
364	imx_pcm_fiq = params->irq;
365
366	imx_ssi_fiq_base = (unsigned long)params->base;
367
368	params->dma_params_tx->maxburst = 4;
369	params->dma_params_rx->maxburst = 6;
370
371	ret = devm_snd_soc_register_component(&pdev->dev, &imx_soc_component_fiq,
372					      NULL, 0);
373	if (ret)
374		goto failed_register;
375
376	return 0;
377
378failed_register:
379	mxc_set_irq_fiq(ssi_irq, 0);
380	release_fiq(&fh);
381
382	return ret;
383}
384EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
385
386void imx_pcm_fiq_exit(struct platform_device *pdev)
387{
388}
389EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
390
391MODULE_LICENSE("GPL");
392