xref: /openbmc/linux/sound/soc/fsl/imx-pcm-fiq.c (revision 5bd8e16d)
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 	unsigned long last_offset;
43 	unsigned long size;
44 	struct hrtimer hrt;
45 	int poll_time_ns;
46 	struct snd_pcm_substream *substream;
47 	atomic_t running;
48 };
49 
50 static enum hrtimer_restart snd_hrtimer_callback(struct hrtimer *hrt)
51 {
52 	struct imx_pcm_runtime_data *iprtd =
53 		container_of(hrt, struct imx_pcm_runtime_data, hrt);
54 	struct snd_pcm_substream *substream = iprtd->substream;
55 	struct snd_pcm_runtime *runtime = substream->runtime;
56 	struct pt_regs regs;
57 	unsigned long delta;
58 
59 	if (!atomic_read(&iprtd->running))
60 		return HRTIMER_NORESTART;
61 
62 	get_fiq_regs(&regs);
63 
64 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
65 		iprtd->offset = regs.ARM_r8 & 0xffff;
66 	else
67 		iprtd->offset = regs.ARM_r9 & 0xffff;
68 
69 	/* How much data have we transferred since the last period report? */
70 	if (iprtd->offset >= iprtd->last_offset)
71 		delta = iprtd->offset - iprtd->last_offset;
72 	else
73 		delta = runtime->buffer_size + iprtd->offset
74 			- iprtd->last_offset;
75 
76 	/* If we've transferred at least a period then report it and
77 	 * reset our poll time */
78 	if (delta >= iprtd->period) {
79 		snd_pcm_period_elapsed(substream);
80 		iprtd->last_offset = iprtd->offset;
81 	}
82 
83 	hrtimer_forward_now(hrt, ns_to_ktime(iprtd->poll_time_ns));
84 
85 	return HRTIMER_RESTART;
86 }
87 
88 static struct fiq_handler fh = {
89 	.name		= DRV_NAME,
90 };
91 
92 static int snd_imx_pcm_hw_params(struct snd_pcm_substream *substream,
93 				struct snd_pcm_hw_params *params)
94 {
95 	struct snd_pcm_runtime *runtime = substream->runtime;
96 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
97 
98 	iprtd->size = params_buffer_bytes(params);
99 	iprtd->periods = params_periods(params);
100 	iprtd->period = params_period_bytes(params) ;
101 	iprtd->offset = 0;
102 	iprtd->last_offset = 0;
103 	iprtd->poll_time_ns = 1000000000 / params_rate(params) *
104 				params_period_size(params);
105 	snd_pcm_set_runtime_buffer(substream, &substream->dma_buffer);
106 
107 	return 0;
108 }
109 
110 static int snd_imx_pcm_prepare(struct snd_pcm_substream *substream)
111 {
112 	struct snd_pcm_runtime *runtime = substream->runtime;
113 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
114 	struct pt_regs regs;
115 
116 	get_fiq_regs(&regs);
117 	if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
118 		regs.ARM_r8 = (iprtd->period * iprtd->periods - 1) << 16;
119 	else
120 		regs.ARM_r9 = (iprtd->period * iprtd->periods - 1) << 16;
121 
122 	set_fiq_regs(&regs);
123 
124 	return 0;
125 }
126 
127 static int fiq_enable;
128 static int imx_pcm_fiq;
129 
130 static int snd_imx_pcm_trigger(struct snd_pcm_substream *substream, int cmd)
131 {
132 	struct snd_pcm_runtime *runtime = substream->runtime;
133 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
134 
135 	switch (cmd) {
136 	case SNDRV_PCM_TRIGGER_START:
137 	case SNDRV_PCM_TRIGGER_RESUME:
138 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
139 		atomic_set(&iprtd->running, 1);
140 		hrtimer_start(&iprtd->hrt, ns_to_ktime(iprtd->poll_time_ns),
141 		      HRTIMER_MODE_REL);
142 		if (++fiq_enable == 1)
143 			enable_fiq(imx_pcm_fiq);
144 
145 		break;
146 
147 	case SNDRV_PCM_TRIGGER_STOP:
148 	case SNDRV_PCM_TRIGGER_SUSPEND:
149 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
150 		atomic_set(&iprtd->running, 0);
151 
152 		if (--fiq_enable == 0)
153 			disable_fiq(imx_pcm_fiq);
154 
155 		break;
156 	default:
157 		return -EINVAL;
158 	}
159 
160 	return 0;
161 }
162 
163 static snd_pcm_uframes_t snd_imx_pcm_pointer(struct snd_pcm_substream *substream)
164 {
165 	struct snd_pcm_runtime *runtime = substream->runtime;
166 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
167 
168 	return bytes_to_frames(substream->runtime, iprtd->offset);
169 }
170 
171 static struct snd_pcm_hardware snd_imx_hardware = {
172 	.info = SNDRV_PCM_INFO_INTERLEAVED |
173 		SNDRV_PCM_INFO_BLOCK_TRANSFER |
174 		SNDRV_PCM_INFO_MMAP |
175 		SNDRV_PCM_INFO_MMAP_VALID |
176 		SNDRV_PCM_INFO_PAUSE |
177 		SNDRV_PCM_INFO_RESUME,
178 	.formats = SNDRV_PCM_FMTBIT_S16_LE,
179 	.rate_min = 8000,
180 	.channels_min = 2,
181 	.channels_max = 2,
182 	.buffer_bytes_max = IMX_SSI_DMABUF_SIZE,
183 	.period_bytes_min = 128,
184 	.period_bytes_max = 16 * 1024,
185 	.periods_min = 4,
186 	.periods_max = 255,
187 	.fifo_size = 0,
188 };
189 
190 static int snd_imx_open(struct snd_pcm_substream *substream)
191 {
192 	struct snd_pcm_runtime *runtime = substream->runtime;
193 	struct imx_pcm_runtime_data *iprtd;
194 	int ret;
195 
196 	iprtd = kzalloc(sizeof(*iprtd), GFP_KERNEL);
197 	if (iprtd == NULL)
198 		return -ENOMEM;
199 	runtime->private_data = iprtd;
200 
201 	iprtd->substream = substream;
202 
203 	atomic_set(&iprtd->running, 0);
204 	hrtimer_init(&iprtd->hrt, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
205 	iprtd->hrt.function = snd_hrtimer_callback;
206 
207 	ret = snd_pcm_hw_constraint_integer(substream->runtime,
208 			SNDRV_PCM_HW_PARAM_PERIODS);
209 	if (ret < 0) {
210 		kfree(iprtd);
211 		return ret;
212 	}
213 
214 	snd_soc_set_runtime_hwparams(substream, &snd_imx_hardware);
215 	return 0;
216 }
217 
218 static int snd_imx_close(struct snd_pcm_substream *substream)
219 {
220 	struct snd_pcm_runtime *runtime = substream->runtime;
221 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
222 
223 	hrtimer_cancel(&iprtd->hrt);
224 
225 	kfree(iprtd);
226 
227 	return 0;
228 }
229 
230 static int snd_imx_pcm_mmap(struct snd_pcm_substream *substream,
231 		struct vm_area_struct *vma)
232 {
233 	struct snd_pcm_runtime *runtime = substream->runtime;
234 	int ret;
235 
236 	ret = dma_mmap_writecombine(substream->pcm->card->dev, vma,
237 		runtime->dma_area, runtime->dma_addr, runtime->dma_bytes);
238 
239 	pr_debug("%s: ret: %d %p 0x%08x 0x%08x\n", __func__, ret,
240 			runtime->dma_area,
241 			runtime->dma_addr,
242 			runtime->dma_bytes);
243 	return ret;
244 }
245 
246 static struct snd_pcm_ops imx_pcm_ops = {
247 	.open		= snd_imx_open,
248 	.close		= snd_imx_close,
249 	.ioctl		= snd_pcm_lib_ioctl,
250 	.hw_params	= snd_imx_pcm_hw_params,
251 	.prepare	= snd_imx_pcm_prepare,
252 	.trigger	= snd_imx_pcm_trigger,
253 	.pointer	= snd_imx_pcm_pointer,
254 	.mmap		= snd_imx_pcm_mmap,
255 };
256 
257 static int imx_pcm_preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
258 {
259 	struct snd_pcm_substream *substream = pcm->streams[stream].substream;
260 	struct snd_dma_buffer *buf = &substream->dma_buffer;
261 	size_t size = IMX_SSI_DMABUF_SIZE;
262 
263 	buf->dev.type = SNDRV_DMA_TYPE_DEV;
264 	buf->dev.dev = pcm->card->dev;
265 	buf->private_data = NULL;
266 	buf->area = dma_alloc_writecombine(pcm->card->dev, size,
267 					   &buf->addr, GFP_KERNEL);
268 	if (!buf->area)
269 		return -ENOMEM;
270 	buf->bytes = size;
271 
272 	return 0;
273 }
274 
275 static u64 imx_pcm_dmamask = DMA_BIT_MASK(32);
276 
277 static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
278 {
279 	struct snd_card *card = rtd->card->snd_card;
280 	struct snd_pcm *pcm = rtd->pcm;
281 	int ret = 0;
282 
283 	if (!card->dev->dma_mask)
284 		card->dev->dma_mask = &imx_pcm_dmamask;
285 	if (!card->dev->coherent_dma_mask)
286 		card->dev->coherent_dma_mask = DMA_BIT_MASK(32);
287 	if (pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream) {
288 		ret = imx_pcm_preallocate_dma_buffer(pcm,
289 			SNDRV_PCM_STREAM_PLAYBACK);
290 		if (ret)
291 			goto out;
292 	}
293 
294 	if (pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream) {
295 		ret = imx_pcm_preallocate_dma_buffer(pcm,
296 			SNDRV_PCM_STREAM_CAPTURE);
297 		if (ret)
298 			goto out;
299 	}
300 
301 out:
302 	return ret;
303 }
304 
305 static int ssi_irq = 0;
306 
307 static int imx_pcm_fiq_new(struct snd_soc_pcm_runtime *rtd)
308 {
309 	struct snd_pcm *pcm = rtd->pcm;
310 	struct snd_pcm_substream *substream;
311 	int ret;
312 
313 	ret = imx_pcm_new(rtd);
314 	if (ret)
315 		return ret;
316 
317 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
318 	if (substream) {
319 		struct snd_dma_buffer *buf = &substream->dma_buffer;
320 
321 		imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
322 	}
323 
324 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
325 	if (substream) {
326 		struct snd_dma_buffer *buf = &substream->dma_buffer;
327 
328 		imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
329 	}
330 
331 	set_fiq_handler(&imx_ssi_fiq_start,
332 		&imx_ssi_fiq_end - &imx_ssi_fiq_start);
333 
334 	return 0;
335 }
336 
337 static void imx_pcm_free(struct snd_pcm *pcm)
338 {
339 	struct snd_pcm_substream *substream;
340 	struct snd_dma_buffer *buf;
341 	int stream;
342 
343 	for (stream = 0; stream < 2; stream++) {
344 		substream = pcm->streams[stream].substream;
345 		if (!substream)
346 			continue;
347 
348 		buf = &substream->dma_buffer;
349 		if (!buf->area)
350 			continue;
351 
352 		dma_free_writecombine(pcm->card->dev, buf->bytes,
353 				      buf->area, buf->addr);
354 		buf->area = NULL;
355 	}
356 }
357 
358 static void imx_pcm_fiq_free(struct snd_pcm *pcm)
359 {
360 	mxc_set_irq_fiq(ssi_irq, 0);
361 	release_fiq(&fh);
362 	imx_pcm_free(pcm);
363 }
364 
365 static struct snd_soc_platform_driver imx_soc_platform_fiq = {
366 	.ops		= &imx_pcm_ops,
367 	.pcm_new	= imx_pcm_fiq_new,
368 	.pcm_free	= imx_pcm_fiq_free,
369 };
370 
371 int imx_pcm_fiq_init(struct platform_device *pdev,
372 		struct imx_pcm_fiq_params *params)
373 {
374 	int ret;
375 
376 	ret = claim_fiq(&fh);
377 	if (ret) {
378 		dev_err(&pdev->dev, "failed to claim fiq: %d", ret);
379 		return ret;
380 	}
381 
382 	mxc_set_irq_fiq(params->irq, 1);
383 	ssi_irq = params->irq;
384 
385 	imx_pcm_fiq = params->irq;
386 
387 	imx_ssi_fiq_base = (unsigned long)params->base;
388 
389 	params->dma_params_tx->maxburst = 4;
390 	params->dma_params_rx->maxburst = 6;
391 
392 	ret = snd_soc_register_platform(&pdev->dev, &imx_soc_platform_fiq);
393 	if (ret)
394 		goto failed_register;
395 
396 	return 0;
397 
398 failed_register:
399 	mxc_set_irq_fiq(ssi_irq, 0);
400 	release_fiq(&fh);
401 
402 	return ret;
403 }
404 EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
405 
406 void imx_pcm_fiq_exit(struct platform_device *pdev)
407 {
408 	snd_soc_unregister_platform(&pdev->dev);
409 }
410 EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
411 
412 MODULE_LICENSE("GPL");
413