xref: /openbmc/linux/sound/soc/fsl/imx-pcm-fiq.c (revision b78412b8)
1 /*
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  *  This program is free software; you can redistribute  it and/or modify it
10  *  under  the terms of  the GNU General  Public License as published by the
11  *  Free Software Foundation;  either version 2 of the  License, or (at your
12  *  option) any later version.
13  */
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/device.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/init.h>
19 #include <linux/interrupt.h>
20 #include <linux/module.h>
21 #include <linux/platform_device.h>
22 #include <linux/slab.h>
23 
24 #include <sound/core.h>
25 #include <sound/dmaengine_pcm.h>
26 #include <sound/initval.h>
27 #include <sound/pcm.h>
28 #include <sound/pcm_params.h>
29 #include <sound/soc.h>
30 
31 #include <asm/fiq.h>
32 
33 #include <linux/platform_data/asoc-imx-ssi.h>
34 
35 #include "imx-ssi.h"
36 #include "imx-pcm.h"
37 
38 struct imx_pcm_runtime_data {
39 	unsigned int period;
40 	int periods;
41 	unsigned long offset;
42 	struct hrtimer hrt;
43 	int poll_time_ns;
44 	struct snd_pcm_substream *substream;
45 	atomic_t playing;
46 	atomic_t capturing;
47 };
48 
49 static enum hrtimer_restart snd_hrtimer_callback(struct hrtimer *hrt)
50 {
51 	struct imx_pcm_runtime_data *iprtd =
52 		container_of(hrt, struct imx_pcm_runtime_data, hrt);
53 	struct snd_pcm_substream *substream = iprtd->substream;
54 	struct pt_regs regs;
55 
56 	if (!atomic_read(&iprtd->playing) && !atomic_read(&iprtd->capturing))
57 		return HRTIMER_NORESTART;
58 
59 	get_fiq_regs(&regs);
60 
61 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
62 		iprtd->offset = regs.ARM_r8 & 0xffff;
63 	else
64 		iprtd->offset = regs.ARM_r9 & 0xffff;
65 
66 	snd_pcm_period_elapsed(substream);
67 
68 	hrtimer_forward_now(hrt, ns_to_ktime(iprtd->poll_time_ns));
69 
70 	return HRTIMER_RESTART;
71 }
72 
73 static struct fiq_handler fh = {
74 	.name		= DRV_NAME,
75 };
76 
77 static int snd_imx_pcm_hw_params(struct snd_pcm_substream *substream,
78 				struct snd_pcm_hw_params *params)
79 {
80 	struct snd_pcm_runtime *runtime = substream->runtime;
81 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
82 
83 	iprtd->periods = params_periods(params);
84 	iprtd->period = params_period_bytes(params);
85 	iprtd->offset = 0;
86 	iprtd->poll_time_ns = 1000000000 / params_rate(params) *
87 				params_period_size(params);
88 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
89 
90 	return 0;
91 }
92 
93 static int snd_imx_pcm_prepare(struct snd_pcm_substream *substream)
94 {
95 	struct snd_pcm_runtime *runtime = substream->runtime;
96 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
97 	struct pt_regs regs;
98 
99 	get_fiq_regs(&regs);
100 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
101 		regs.ARM_r8 = (iprtd->period * iprtd->periods - 1) << 16;
102 	else
103 		regs.ARM_r9 = (iprtd->period * iprtd->periods - 1) << 16;
104 
105 	set_fiq_regs(&regs);
106 
107 	return 0;
108 }
109 
110 static int imx_pcm_fiq;
111 
112 static int snd_imx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
113 {
114 	struct snd_pcm_runtime *runtime = substream->runtime;
115 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
116 
117 	switch (cmd) {
118 	case SNDRV_PCM_TRIGGER_START:
119 	case SNDRV_PCM_TRIGGER_RESUME:
120 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
121 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
122 			atomic_set(&iprtd->playing, 1);
123 		else
124 			atomic_set(&iprtd->capturing, 1);
125 		hrtimer_start(&iprtd->hrt, ns_to_ktime(iprtd->poll_time_ns),
126 		      HRTIMER_MODE_REL);
127 		enable_fiq(imx_pcm_fiq);
128 		break;
129 
130 	case SNDRV_PCM_TRIGGER_STOP:
131 	case SNDRV_PCM_TRIGGER_SUSPEND:
132 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
133 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
134 			atomic_set(&iprtd->playing, 0);
135 		else
136 			atomic_set(&iprtd->capturing, 0);
137 		if (!atomic_read(&iprtd->playing) &&
138 				!atomic_read(&iprtd->capturing))
139 			disable_fiq(imx_pcm_fiq);
140 		break;
141 
142 	default:
143 		return -EINVAL;
144 	}
145 
146 	return 0;
147 }
148 
149 static snd_pcm_uframes_t snd_imx_pcm_pointer(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_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 
202 static int snd_imx_close(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 
214 static int snd_imx_pcm_mmap(struct snd_pcm_substream *substream,
215 		struct vm_area_struct *vma)
216 {
217 	struct snd_pcm_runtime *runtime = substream->runtime;
218 	int ret;
219 
220 	ret = dma_mmap_wc(substream->pcm->card->dev, vma, runtime->dma_area,
221 			  runtime->dma_addr, runtime->dma_bytes);
222 
223 	pr_debug("%s: ret: %d %p %pad 0x%08zx\n", __func__, ret,
224 			runtime->dma_area,
225 			&runtime->dma_addr,
226 			runtime->dma_bytes);
227 	return ret;
228 }
229 
230 static const struct snd_pcm_ops imx_pcm_ops = {
231 	.open		= snd_imx_open,
232 	.close		= snd_imx_close,
233 	.ioctl		= snd_pcm_lib_ioctl,
234 	.hw_params	= snd_imx_pcm_hw_params,
235 	.prepare	= snd_imx_pcm_prepare,
236 	.trigger	= snd_imx_pcm_trigger,
237 	.pointer	= snd_imx_pcm_pointer,
238 	.mmap		= snd_imx_pcm_mmap,
239 };
240 
241 static int imx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
242 {
243 	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
244 	struct snd_dma_buffer *buf = &substream->dma_buffer;
245 	size_t size = IMX_SSI_DMABUF_SIZE;
246 
247 	buf->dev.type = SNDRV_DMA_TYPE_DEV;
248 	buf->dev.dev = pcm->card->dev;
249 	buf->private_data = NULL;
250 	buf->area = dma_alloc_wc(pcm->card->dev, size, &buf->addr, GFP_KERNEL);
251 	if (!buf->area)
252 		return -ENOMEM;
253 	buf->bytes = size;
254 
255 	return 0;
256 }
257 
258 static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
259 {
260 	struct snd_card *card = rtd->card->snd_card;
261 	struct snd_pcm *pcm = rtd->pcm;
262 	int ret;
263 
264 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
265 	if (ret)
266 		return ret;
267 
268 	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
269 		ret = imx_pcm_preallocate_dma_buffer(pcm,
270 			SNDRV_PCM_STREAM_PLAYBACK);
271 		if (ret)
272 			return ret;
273 	}
274 
275 	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
276 		ret = imx_pcm_preallocate_dma_buffer(pcm,
277 			SNDRV_PCM_STREAM_CAPTURE);
278 		if (ret)
279 			return ret;
280 	}
281 
282 	return 0;
283 }
284 
285 static int ssi_irq;
286 
287 static int imx_pcm_fiq_new(struct snd_soc_pcm_runtime *rtd)
288 {
289 	struct snd_pcm *pcm = rtd->pcm;
290 	struct snd_pcm_substream *substream;
291 	int ret;
292 
293 	ret = imx_pcm_new(rtd);
294 	if (ret)
295 		return ret;
296 
297 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
298 	if (substream) {
299 		struct snd_dma_buffer *buf = &substream->dma_buffer;
300 
301 		imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
302 	}
303 
304 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
305 	if (substream) {
306 		struct snd_dma_buffer *buf = &substream->dma_buffer;
307 
308 		imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
309 	}
310 
311 	set_fiq_handler(&imx_ssi_fiq_start,
312 		&imx_ssi_fiq_end - &imx_ssi_fiq_start);
313 
314 	return 0;
315 }
316 
317 static void imx_pcm_free(struct snd_pcm *pcm)
318 {
319 	struct snd_pcm_substream *substream;
320 	struct snd_dma_buffer *buf;
321 	int stream;
322 
323 	for (stream = 0; stream < 2; stream++) {
324 		substream = pcm->streams[stream].substream;
325 		if (!substream)
326 			continue;
327 
328 		buf = &substream->dma_buffer;
329 		if (!buf->area)
330 			continue;
331 
332 		dma_free_wc(pcm->card->dev, buf->bytes, buf->area, buf->addr);
333 		buf->area = NULL;
334 	}
335 }
336 
337 static void imx_pcm_fiq_free(struct snd_pcm *pcm)
338 {
339 	mxc_set_irq_fiq(ssi_irq, 0);
340 	release_fiq(&fh);
341 	imx_pcm_free(pcm);
342 }
343 
344 static const struct snd_soc_platform_driver imx_soc_platform_fiq = {
345 	.ops		= &imx_pcm_ops,
346 	.pcm_new	= imx_pcm_fiq_new,
347 	.pcm_free	= imx_pcm_fiq_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 = snd_soc_register_platform(&pdev->dev, &imx_soc_platform_fiq);
372 	if (ret)
373 		goto failed_register;
374 
375 	return 0;
376 
377 failed_register:
378 	mxc_set_irq_fiq(ssi_irq, 0);
379 	release_fiq(&fh);
380 
381 	return ret;
382 }
383 EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
384 
385 void imx_pcm_fiq_exit(struct platform_device *pdev)
386 {
387 	snd_soc_unregister_platform(&pdev->dev);
388 }
389 EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
390 
391 MODULE_LICENSE("GPL");
392