xref: /openbmc/linux/sound/soc/fsl/imx-pcm-fiq.c (revision d9fd5a71)
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 
33 struct 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 
44 static 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 
68 static struct fiq_handler fh = {
69 	.name		= DRV_NAME,
70 };
71 
72 static 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 
89 static 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 
107 static int imx_pcm_fiq;
108 
109 static 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 
147 static snd_pcm_uframes_t
148 snd_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 
157 static 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 
173 static 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 
203 static 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 
216 static 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 
233 static 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 
250 static 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 
277 static int ssi_irq;
278 
279 static 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 
310 static 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 
330 static 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 
338 static 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 
350 int 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 
378 failed_register:
379 	mxc_set_irq_fiq(ssi_irq, 0);
380 	release_fiq(&fh);
381 
382 	return ret;
383 }
384 EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
385 
386 void imx_pcm_fiq_exit(struct platform_device *pdev)
387 {
388 }
389 EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
390 
391 MODULE_LICENSE("GPL");
392