xref: /openbmc/linux/sound/soc/fsl/imx-pcm-fiq.c (revision 63705da3)
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 
85 	return 0;
86 }
87 
88 static 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 
106 static int imx_pcm_fiq;
107 
108 static 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 
146 static snd_pcm_uframes_t
147 snd_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 
156 static 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 
172 static 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_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_soc_component *component,
203 			 struct snd_pcm_substream *substream)
204 {
205 	struct snd_pcm_runtime *runtime = substream->runtime;
206 	struct imx_pcm_runtime_data *iprtd = runtime->private_data;
207 
208 	hrtimer_cancel(&iprtd->hrt);
209 
210 	kfree(iprtd);
211 
212 	return 0;
213 }
214 
215 static int imx_pcm_new(struct snd_soc_pcm_runtime *rtd)
216 {
217 	struct snd_card *card = rtd->card->snd_card;
218 	struct snd_pcm *pcm = rtd->pcm;
219 	int ret;
220 
221 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
222 	if (ret)
223 		return ret;
224 
225 	return snd_pcm_set_fixed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV_WC,
226 					    pcm->card->dev,
227 					    IMX_SSI_DMABUF_SIZE);
228 }
229 
230 static int ssi_irq;
231 
232 static int snd_imx_pcm_new(struct snd_soc_component *component,
233 			   struct snd_soc_pcm_runtime *rtd)
234 {
235 	struct snd_pcm *pcm = rtd->pcm;
236 	struct snd_pcm_substream *substream;
237 	int ret;
238 
239 	ret = imx_pcm_new(rtd);
240 	if (ret)
241 		return ret;
242 
243 	substream = pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
244 	if (substream) {
245 		struct snd_dma_buffer *buf = &substream->dma_buffer;
246 
247 		imx_ssi_fiq_tx_buffer = (unsigned long)buf->area;
248 	}
249 
250 	substream = pcm->streams[SNDRV_PCM_STREAM_CAPTURE].substream;
251 	if (substream) {
252 		struct snd_dma_buffer *buf = &substream->dma_buffer;
253 
254 		imx_ssi_fiq_rx_buffer = (unsigned long)buf->area;
255 	}
256 
257 	set_fiq_handler(&imx_ssi_fiq_start,
258 		&imx_ssi_fiq_end - &imx_ssi_fiq_start);
259 
260 	return 0;
261 }
262 
263 static void snd_imx_pcm_free(struct snd_soc_component *component,
264 			     struct snd_pcm *pcm)
265 {
266 	mxc_set_irq_fiq(ssi_irq, 0);
267 	release_fiq(&fh);
268 }
269 
270 static const struct snd_soc_component_driver imx_soc_component_fiq = {
271 	.open		= snd_imx_open,
272 	.close		= snd_imx_close,
273 	.hw_params	= snd_imx_pcm_hw_params,
274 	.prepare	= snd_imx_pcm_prepare,
275 	.trigger	= snd_imx_pcm_trigger,
276 	.pointer	= snd_imx_pcm_pointer,
277 	.pcm_construct	= snd_imx_pcm_new,
278 	.pcm_destruct	= snd_imx_pcm_free,
279 };
280 
281 int imx_pcm_fiq_init(struct platform_device *pdev,
282 		struct imx_pcm_fiq_params *params)
283 {
284 	int ret;
285 
286 	ret = claim_fiq(&fh);
287 	if (ret) {
288 		dev_err(&pdev->dev, "failed to claim fiq: %d", ret);
289 		return ret;
290 	}
291 
292 	mxc_set_irq_fiq(params->irq, 1);
293 	ssi_irq = params->irq;
294 
295 	imx_pcm_fiq = params->irq;
296 
297 	imx_ssi_fiq_base = (unsigned long)params->base;
298 
299 	params->dma_params_tx->maxburst = 4;
300 	params->dma_params_rx->maxburst = 6;
301 
302 	ret = devm_snd_soc_register_component(&pdev->dev, &imx_soc_component_fiq,
303 					      NULL, 0);
304 	if (ret)
305 		goto failed_register;
306 
307 	return 0;
308 
309 failed_register:
310 	mxc_set_irq_fiq(ssi_irq, 0);
311 	release_fiq(&fh);
312 
313 	return ret;
314 }
315 EXPORT_SYMBOL_GPL(imx_pcm_fiq_init);
316 
317 void imx_pcm_fiq_exit(struct platform_device *pdev)
318 {
319 }
320 EXPORT_SYMBOL_GPL(imx_pcm_fiq_exit);
321 
322 MODULE_LICENSE("GPL");
323