imx-pcm-fiq.c

  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_setup(&iprtd->hrt, snd_hrtimer_callback, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
189
190	ret = snd_pcm_hw_constraint_integer(substream->runtime,
191			SNDRV_PCM_HW_PARAM_PERIODS);
192	if (ret < 0) {
193		kfree(iprtd);
194		return ret;
195	}
196
197	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
198	return 0;
199}
200
201static int snd_imx_close(struct snd_soc_component *component,
202			 struct snd_pcm_substream *substream)
203{
204	struct snd_pcm_runtime *runtime = substream->runtime;
205	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
206
207	hrtimer_cancel(&iprtd->hrt);
208
209	kfree(iprtd);
210
211	return 0;
212}
213
214static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
215{
216	struct snd_card *card = rtd->card->snd_card;
217	struct snd_pcm *pcm = rtd->pcm;
218	int ret;
219
220	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
221	if (ret)
222		return ret;
223
224	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV_WC,
225					    pcm->card->dev,
226					    IMX_SSI_DMABUF_SIZE);
227}
228
229static int ssi_irq;
230
231static int snd_imx_pcm_new(struct snd_soc_component *component,
232			   struct snd_soc_pcm_runtime *rtd)
233{
234	struct snd_pcm *pcm = rtd->pcm;
235	struct snd_pcm_substream *substream;
236	int ret;
237
238	ret = imx_pcm_new(rtd);
239	if (ret)
240		return ret;
241
242	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
243	if (substream) {
244		struct snd_dma_buffer *buf = &substream->dma_buffer;
245
246		imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
247	}
248
249	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
250	if (substream) {
251		struct snd_dma_buffer *buf = &substream->dma_buffer;
252
253		imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
254	}
255
256	set_fiq_handler(&imx_ssi_fiq_start,
257		&imx_ssi_fiq_end - &imx_ssi_fiq_start);
258
259	return 0;
260}
261
262static void snd_imx_pcm_free(struct snd_soc_component *component,
263			     struct snd_pcm *pcm)
264{
265	mxc_set_irq_fiq(ssi_irq, 0);
266	release_fiq(&fh);
267}
268
269static const struct snd_soc_component_driver imx_soc_component_fiq = {
270	.open		= snd_imx_open,
271	.close		= snd_imx_close,
272	.hw_params	= snd_imx_pcm_hw_params,
273	.prepare	= snd_imx_pcm_prepare,
274	.trigger	= snd_imx_pcm_trigger,
275	.pointer	= snd_imx_pcm_pointer,
276	.pcm_construct	= snd_imx_pcm_new,
277	.pcm_destruct	= snd_imx_pcm_free,
278};
279
280int imx_pcm_fiq_init(struct platform_device *pdev,
281		struct imx_pcm_fiq_params *params)
282{
283	int ret;
284
285	ret = claim_fiq(&fh);
286	if (ret) {
287		dev_err(&pdev->dev, "failed to claim fiq: %d", ret);
288		return ret;
289	}
290
291	mxc_set_irq_fiq(params->irq, 1);
292	ssi_irq = params->irq;
293
294	imx_pcm_fiq = params->irq;
295
296	imx_ssi_fiq_base = (unsigned long)params->base;
297
298	params->dma_params_tx->maxburst = 4;
299	params->dma_params_rx->maxburst = 6;
300
301	ret = devm_snd_soc_register_component(&pdev->dev, &imx_soc_component_fiq,
302					      NULL, 0);
303	if (ret)
304		goto failed_register;
305
306	return 0;
307
308failed_register:
309	mxc_set_irq_fiq(ssi_irq, 0);
310	release_fiq(&fh);
311
312	return ret;
313}
314EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
315
316void imx_pcm_fiq_exit(struct platform_device *pdev)
317{
318}
319EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
320
321MODULE_DESCRIPTION("Freescale i.MX PCM FIQ handler");
322MODULE_LICENSE("GPL");