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
85	return 0;
86}
87
88static int snd_imx_pcm_prepare(struct snd_soc_component *component,
89			       struct snd_pcm_substream *substream)
90{
91	struct snd_pcm_runtime *runtime = substream->runtime;
92	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
93	struct pt_regs regs;
94
95	get_fiq_regs(&regs);
96	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
97		regs.ARM_r8 = (iprtd->period * iprtd->periods - 1) << 16;
98	else
99		regs.ARM_r9 = (iprtd->period * iprtd->periods - 1) << 16;
100
101	set_fiq_regs(&regs);
102
103	return 0;
104}
105
106static int imx_pcm_fiq;
107
108static int snd_imx_pcm_trigger(struct snd_soc_component *component,
109			       struct snd_pcm_substream *substream, int cmd)
110{
111	struct snd_pcm_runtime *runtime = substream->runtime;
112	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
113
114	switch (cmd) {
115	case SNDRV_PCM_TRIGGER_START:
116	case SNDRV_PCM_TRIGGER_RESUME:
117	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
118		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
119			atomic_set(&iprtd->playing, 1);
120		else
121			atomic_set(&iprtd->capturing, 1);
122		hrtimer_start(&iprtd->hrt, ns_to_ktime(iprtd->poll_time_ns),
123		      HRTIMER_MODE_REL);
124		enable_fiq(imx_pcm_fiq);
125		break;
126
127	case SNDRV_PCM_TRIGGER_STOP:
128	case SNDRV_PCM_TRIGGER_SUSPEND:
129	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
130		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
131			atomic_set(&iprtd->playing, 0);
132		else
133			atomic_set(&iprtd->capturing, 0);
134		if (!atomic_read(&iprtd->playing) &&
135				!atomic_read(&iprtd->capturing))
136			disable_fiq(imx_pcm_fiq);
137		break;
138
139	default:
140		return -EINVAL;
141	}
142
143	return 0;
144}
145
146static snd_pcm_uframes_t
147snd_imx_pcm_pointer(struct snd_soc_component *component,
148		    struct snd_pcm_substream *substream)
149{
150	struct snd_pcm_runtime *runtime = substream->runtime;
151	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
152
153	return bytes_to_frames(substream->runtime, iprtd->offset);
154}
155
156static const struct snd_pcm_hardware snd_imx_hardware = {
157	.info = SNDRV_PCM_INFO_INTERLEAVED |
158		SNDRV_PCM_INFO_BLOCK_TRANSFER |
159		SNDRV_PCM_INFO_MMAP |
160		SNDRV_PCM_INFO_MMAP_VALID |
161		SNDRV_PCM_INFO_PAUSE |
162		SNDRV_PCM_INFO_RESUME,
163	.formats = SNDRV_PCM_FMTBIT_S16_LE,
164	.buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
165	.period_bytes_min = 128,
166	.period_bytes_max = 16 * 1024,
167	.periods_min = 4,
168	.periods_max = 255,
169	.fifo_size = 0,
170};
171
172static int snd_imx_open(struct snd_soc_component *component,
173			struct snd_pcm_substream *substream)
174{
175	struct snd_pcm_runtime *runtime = substream->runtime;
176	struct imx_pcm_runtime_data *iprtd;
177	int ret;
178
179	iprtd = kzalloc(sizeof(*iprtd), GFP_KERNEL);
180	if (iprtd == NULL)
181		return -ENOMEM;
182	runtime->private_data = iprtd;
183
184	iprtd->substream = substream;
185
186	atomic_set(&iprtd->playing, 0);
187	atomic_set(&iprtd->capturing, 0);
188	hrtimer_init(&iprtd->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
189	iprtd->hrt.function = snd_hrtimer_callback;
190
191	ret = snd_pcm_hw_constraint_integer(substream->runtime,
192			SNDRV_PCM_HW_PARAM_PERIODS);
193	if (ret < 0) {
194		kfree(iprtd);
195		return ret;
196	}
197
198	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
199	return 0;
200}
201
202static int snd_imx_close(struct snd_soc_component *component,
203			 struct snd_pcm_substream *substream)
204{
205	struct snd_pcm_runtime *runtime = substream->runtime;
206	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
207
208	hrtimer_cancel(&iprtd->hrt);
209
210	kfree(iprtd);
211
212	return 0;
213}
214
215static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
216{
217	struct snd_card *card = rtd->card->snd_card;
218	struct snd_pcm *pcm = rtd->pcm;
219	int ret;
220
221	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
222	if (ret)
223		return ret;
224
225	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV_WC,
226					    pcm->card->dev,
227					    IMX_SSI_DMABUF_SIZE);
228}
229
230static int ssi_irq;
231
232static int snd_imx_pcm_new(struct snd_soc_component *component,
233			   struct snd_soc_pcm_runtime *rtd)
234{
235	struct snd_pcm *pcm = rtd->pcm;
236	struct snd_pcm_substream *substream;
237	int ret;
238
239	ret = imx_pcm_new(rtd);
240	if (ret)
241		return ret;
242
243	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
244	if (substream) {
245		struct snd_dma_buffer *buf = &substream->dma_buffer;
246
247		imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
248	}
249
250	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
251	if (substream) {
252		struct snd_dma_buffer *buf = &substream->dma_buffer;
253
254		imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
255	}
256
257	set_fiq_handler(&imx_ssi_fiq_start,
258		&imx_ssi_fiq_end - &imx_ssi_fiq_start);
259
260	return 0;
261}
262
263static void snd_imx_pcm_free(struct snd_soc_component *component,
264			     struct snd_pcm *pcm)
265{
266	mxc_set_irq_fiq(ssi_irq, 0);
267	release_fiq(&fh);
268}
269
270static const struct snd_soc_component_driver imx_soc_component_fiq = {
271	.open		= snd_imx_open,
272	.close		= snd_imx_close,
273	.hw_params	= snd_imx_pcm_hw_params,
274	.prepare	= snd_imx_pcm_prepare,
275	.trigger	= snd_imx_pcm_trigger,
276	.pointer	= snd_imx_pcm_pointer,
277	.pcm_construct	= snd_imx_pcm_new,
278	.pcm_destruct	= snd_imx_pcm_free,
279};
280
281int imx_pcm_fiq_init(struct platform_device *pdev,
282		struct imx_pcm_fiq_params *params)
283{
284	int ret;
285
286	ret = claim_fiq(&fh);
287	if (ret) {
288		dev_err(&pdev->dev, "failed to claim fiq: %d", ret);
289		return ret;
290	}
291
292	mxc_set_irq_fiq(params->irq, 1);
293	ssi_irq = params->irq;
294
295	imx_pcm_fiq = params->irq;
296
297	imx_ssi_fiq_base = (unsigned long)params->base;
298
299	params->dma_params_tx->maxburst = 4;
300	params->dma_params_rx->maxburst = 6;
301
302	ret = devm_snd_soc_register_component(&pdev->dev, &imx_soc_component_fiq,
303					      NULL, 0);
304	if (ret)
305		goto failed_register;
306
307	return 0;
308
309failed_register:
310	mxc_set_irq_fiq(ssi_irq, 0);
311	release_fiq(&fh);
312
313	return ret;
314}
315EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
316
317void imx_pcm_fiq_exit(struct platform_device *pdev)
318{
319}
320EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
321
322MODULE_LICENSE("GPL");
323