xref: /openbmc/linux/sound/soc/fsl/imx-pcm-fiq.c (revision d6437c14)
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 snd_pcm_runtime *runtime = substream->runtime;
55 	struct pt_regs regs;
56 
57 	if (!atomic_read(&iprtd->playing) && !atomic_read(&iprtd->capturing))
58 		return HRTIMER_NORESTART;
59 
60 	get_fiq_regs(&regs);
61 
62 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
63 		iprtd->offset = regs.ARM_r8 & 0xffff;
64 	else
65 		iprtd->offset = regs.ARM_r9 & 0xffff;
66 
67 	snd_pcm_period_elapsed(substream);
68 
69 	hrtimer_forward_now(hrt, ns_to_ktime(iprtd->poll_time_ns));
70 
71 	return HRTIMER_RESTART;
72 }
73 
74 static struct fiq_handler fh = {
75 	.name		= DRV_NAME,
76 };
77 
78 static int snd_imx_pcm_hw_params(struct snd_pcm_substream *substream,
79 				struct snd_pcm_hw_params *params)
80 {
81 	struct snd_pcm_runtime *runtime = substream->runtime;
82 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
83 
84 	iprtd->periods = params_periods(params);
85 	iprtd->period = params_period_bytes(params);
86 	iprtd->offset = 0;
87 	iprtd->poll_time_ns = 1000000000 / params_rate(params) *
88 				params_period_size(params);
89 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
90 
91 	return 0;
92 }
93 
94 static int snd_imx_pcm_prepare(struct snd_pcm_substream *substream)
95 {
96 	struct snd_pcm_runtime *runtime = substream->runtime;
97 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
98 	struct pt_regs regs;
99 
100 	get_fiq_regs(&regs);
101 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
102 		regs.ARM_r8 = (iprtd->period * iprtd->periods - 1) << 16;
103 	else
104 		regs.ARM_r9 = (iprtd->period * iprtd->periods - 1) << 16;
105 
106 	set_fiq_regs(&regs);
107 
108 	return 0;
109 }
110 
111 static int imx_pcm_fiq;
112 
113 static int snd_imx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
114 {
115 	struct snd_pcm_runtime *runtime = substream->runtime;
116 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
117 
118 	switch (cmd) {
119 	case SNDRV_PCM_TRIGGER_START:
120 	case SNDRV_PCM_TRIGGER_RESUME:
121 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
122 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
123 			atomic_set(&iprtd->playing, 1);
124 		else
125 			atomic_set(&iprtd->capturing, 1);
126 		hrtimer_start(&iprtd->hrt, ns_to_ktime(iprtd->poll_time_ns),
127 		      HRTIMER_MODE_REL);
128 		enable_fiq(imx_pcm_fiq);
129 		break;
130 
131 	case SNDRV_PCM_TRIGGER_STOP:
132 	case SNDRV_PCM_TRIGGER_SUSPEND:
133 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
134 		if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
135 			atomic_set(&iprtd->playing, 0);
136 		else
137 			atomic_set(&iprtd->capturing, 0);
138 		if (!atomic_read(&iprtd->playing) &&
139 				!atomic_read(&iprtd->capturing))
140 			disable_fiq(imx_pcm_fiq);
141 		break;
142 
143 	default:
144 		return -EINVAL;
145 	}
146 
147 	return 0;
148 }
149 
150 static snd_pcm_uframes_t snd_imx_pcm_pointer(struct snd_pcm_substream *substream)
151 {
152 	struct snd_pcm_runtime *runtime = substream->runtime;
153 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
154 
155 	return bytes_to_frames(substream->runtime, iprtd->offset);
156 }
157 
158 static struct snd_pcm_hardware snd_imx_hardware = {
159 	.info = SNDRV_PCM_INFO_INTERLEAVED |
160 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
161 		SNDRV_PCM_INFO_MMAP |
162 		SNDRV_PCM_INFO_MMAP_VALID |
163 		SNDRV_PCM_INFO_PAUSE |
164 		SNDRV_PCM_INFO_RESUME,
165 	.formats = SNDRV_PCM_FMTBIT_S16_LE,
166 	.rate_min = 8000,
167 	.channels_min = 2,
168 	.channels_max = 2,
169 	.buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
170 	.period_bytes_min = 128,
171 	.period_bytes_max = 16 * 1024,
172 	.periods_min = 4,
173 	.periods_max = 255,
174 	.fifo_size = 0,
175 };
176 
177 static int snd_imx_open(struct snd_pcm_substream *substream)
178 {
179 	struct snd_pcm_runtime *runtime = substream->runtime;
180 	struct imx_pcm_runtime_data *iprtd;
181 	int ret;
182 
183 	iprtd = kzalloc(sizeof(*iprtd), GFP_KERNEL);
184 	if (iprtd == NULL)
185 		return -ENOMEM;
186 	runtime->private_data = iprtd;
187 
188 	iprtd->substream = substream;
189 
190 	atomic_set(&iprtd->playing, 0);
191 	atomic_set(&iprtd->capturing, 0);
192 	hrtimer_init(&iprtd->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
193 	iprtd->hrt.function = snd_hrtimer_callback;
194 
195 	ret = snd_pcm_hw_constraint_integer(substream->runtime,
196 			SNDRV_PCM_HW_PARAM_PERIODS);
197 	if (ret < 0) {
198 		kfree(iprtd);
199 		return ret;
200 	}
201 
202 	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
203 	return 0;
204 }
205 
206 static int snd_imx_close(struct snd_pcm_substream *substream)
207 {
208 	struct snd_pcm_runtime *runtime = substream->runtime;
209 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
210 
211 	hrtimer_cancel(&iprtd->hrt);
212 
213 	kfree(iprtd);
214 
215 	return 0;
216 }
217 
218 static int snd_imx_pcm_mmap(struct snd_pcm_substream *substream,
219 		struct vm_area_struct *vma)
220 {
221 	struct snd_pcm_runtime *runtime = substream->runtime;
222 	int ret;
223 
224 	ret = dma_mmap_writecombine(substream->pcm->card->dev, vma,
225 		runtime->dma_area, runtime->dma_addr, runtime->dma_bytes);
226 
227 	pr_debug("%s: ret: %d %p 0x%08x 0x%08x\n", __func__, ret,
228 			runtime->dma_area,
229 			runtime->dma_addr,
230 			runtime->dma_bytes);
231 	return ret;
232 }
233 
234 static struct snd_pcm_ops imx_pcm_ops = {
235 	.open		= snd_imx_open,
236 	.close		= snd_imx_close,
237 	.ioctl		= snd_pcm_lib_ioctl,
238 	.hw_params	= snd_imx_pcm_hw_params,
239 	.prepare	= snd_imx_pcm_prepare,
240 	.trigger	= snd_imx_pcm_trigger,
241 	.pointer	= snd_imx_pcm_pointer,
242 	.mmap		= snd_imx_pcm_mmap,
243 };
244 
245 static int imx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
246 {
247 	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
248 	struct snd_dma_buffer *buf = &substream->dma_buffer;
249 	size_t size = IMX_SSI_DMABUF_SIZE;
250 
251 	buf->dev.type = SNDRV_DMA_TYPE_DEV;
252 	buf->dev.dev = pcm->card->dev;
253 	buf->private_data = NULL;
254 	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
255 					   &buf->addr, GFP_KERNEL);
256 	if (!buf->area)
257 		return -ENOMEM;
258 	buf->bytes = size;
259 
260 	return 0;
261 }
262 
263 static u64 imx_pcm_dmamask = DMA_BIT_MASK(32);
264 
265 static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
266 {
267 	struct snd_card *card = rtd->card->snd_card;
268 	struct snd_pcm *pcm = rtd->pcm;
269 	int ret = 0;
270 
271 	if (!card->dev->dma_mask)
272 		card->dev->dma_mask = &imx_pcm_dmamask;
273 	if (!card->dev->coherent_dma_mask)
274 		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
275 	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
276 		ret = imx_pcm_preallocate_dma_buffer(pcm,
277 			SNDRV_PCM_STREAM_PLAYBACK);
278 		if (ret)
279 			goto out;
280 	}
281 
282 	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
283 		ret = imx_pcm_preallocate_dma_buffer(pcm,
284 			SNDRV_PCM_STREAM_CAPTURE);
285 		if (ret)
286 			goto out;
287 	}
288 
289 out:
290 	return ret;
291 }
292 
293 static int ssi_irq = 0;
294 
295 static int imx_pcm_fiq_new(struct snd_soc_pcm_runtime *rtd)
296 {
297 	struct snd_pcm *pcm = rtd->pcm;
298 	struct snd_pcm_substream *substream;
299 	int ret;
300 
301 	ret = imx_pcm_new(rtd);
302 	if (ret)
303 		return ret;
304 
305 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
306 	if (substream) {
307 		struct snd_dma_buffer *buf = &substream->dma_buffer;
308 
309 		imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
310 	}
311 
312 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
313 	if (substream) {
314 		struct snd_dma_buffer *buf = &substream->dma_buffer;
315 
316 		imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
317 	}
318 
319 	set_fiq_handler(&imx_ssi_fiq_start,
320 		&imx_ssi_fiq_end - &imx_ssi_fiq_start);
321 
322 	return 0;
323 }
324 
325 static void imx_pcm_free(struct snd_pcm *pcm)
326 {
327 	struct snd_pcm_substream *substream;
328 	struct snd_dma_buffer *buf;
329 	int stream;
330 
331 	for (stream = 0; stream < 2; stream++) {
332 		substream = pcm->streams[stream].substream;
333 		if (!substream)
334 			continue;
335 
336 		buf = &substream->dma_buffer;
337 		if (!buf->area)
338 			continue;
339 
340 		dma_free_writecombine(pcm->card->dev, buf->bytes,
341 				      buf->area, buf->addr);
342 		buf->area = NULL;
343 	}
344 }
345 
346 static void imx_pcm_fiq_free(struct snd_pcm *pcm)
347 {
348 	mxc_set_irq_fiq(ssi_irq, 0);
349 	release_fiq(&fh);
350 	imx_pcm_free(pcm);
351 }
352 
353 static struct snd_soc_platform_driver imx_soc_platform_fiq = {
354 	.ops		= &imx_pcm_ops,
355 	.pcm_new	= imx_pcm_fiq_new,
356 	.pcm_free	= imx_pcm_fiq_free,
357 };
358 
359 int imx_pcm_fiq_init(struct platform_device *pdev,
360 		struct imx_pcm_fiq_params *params)
361 {
362 	int ret;
363 
364 	ret = claim_fiq(&fh);
365 	if (ret) {
366 		dev_err(&pdev->dev, "failed to claim fiq: %d", ret);
367 		return ret;
368 	}
369 
370 	mxc_set_irq_fiq(params->irq, 1);
371 	ssi_irq = params->irq;
372 
373 	imx_pcm_fiq = params->irq;
374 
375 	imx_ssi_fiq_base = (unsigned long)params->base;
376 
377 	params->dma_params_tx->maxburst = 4;
378 	params->dma_params_rx->maxburst = 6;
379 
380 	ret = snd_soc_register_platform(&pdev->dev, &imx_soc_platform_fiq);
381 	if (ret)
382 		goto failed_register;
383 
384 	return 0;
385 
386 failed_register:
387 	mxc_set_irq_fiq(ssi_irq, 0);
388 	release_fiq(&fh);
389 
390 	return ret;
391 }
392 EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
393 
394 void imx_pcm_fiq_exit(struct platform_device *pdev)
395 {
396 	snd_soc_unregister_platform(&pdev->dev);
397 }
398 EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
399 
400 MODULE_LICENSE("GPL");
401