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10#include <linux/clk.h>
11#include <linux/module.h>
12#include <linux/mutex.h>
13#include <linux/platform_device.h>
14#include <linux/slab.h>
15
16#include <linux/iio/iio.h>
17#include <linux/iio/consumer.h>
18#include <linux/iio/adc/stm32-dfsdm-adc.h>
19
20#include <sound/pcm.h>
21#include <sound/soc.h>
22
23#define STM32_ADFSDM_DRV_NAME "stm32-adfsdm"
24
25#define DFSDM_MAX_PERIOD_SIZE (PAGE_SIZE / 2)
26#define DFSDM_MAX_PERIODS 6
27
28struct stm32_adfsdm_priv {
29 struct snd_soc_dai_driver dai_drv;
30 struct snd_pcm_substream *substream;
31 struct device *dev;
32
33
34 struct iio_channel *iio_ch;
35 struct iio_cb_buffer *iio_cb;
36 bool iio_active;
37
38
39 unsigned char *pcm_buff;
40 unsigned int pos;
41
42 struct mutex lock;
43};
44
45static const struct snd_pcm_hardware stm32_adfsdm_pcm_hw = {
46 .info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
47 SNDRV_PCM_INFO_MMAP | SNDRV_PCM_INFO_PAUSE,
48 .formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S32_LE,
49
50 .channels_min = 1,
51 .channels_max = 1,
52
53 .periods_min = 2,
54 .periods_max = DFSDM_MAX_PERIODS,
55
56 .period_bytes_max = DFSDM_MAX_PERIOD_SIZE,
57 .buffer_bytes_max = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE
58};
59
60static void stm32_adfsdm_shutdown(struct snd_pcm_substream *substream,
61 struct snd_soc_dai *dai)
62{
63 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);
64
65 mutex_lock(&priv->lock);
66 if (priv->iio_active) {
67 iio_channel_stop_all_cb(priv->iio_cb);
68 priv->iio_active = false;
69 }
70 mutex_unlock(&priv->lock);
71}
72
73static int stm32_adfsdm_dai_prepare(struct snd_pcm_substream *substream,
74 struct snd_soc_dai *dai)
75{
76 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);
77 int ret;
78
79 mutex_lock(&priv->lock);
80 if (priv->iio_active) {
81 iio_channel_stop_all_cb(priv->iio_cb);
82 priv->iio_active = false;
83 }
84
85 ret = iio_write_channel_attribute(priv->iio_ch,
86 substream->runtime->rate, 0,
87 IIO_CHAN_INFO_SAMP_FREQ);
88 if (ret < 0) {
89 dev_err(dai->dev, "%s: Failed to set %d sampling rate\n",
90 __func__, substream->runtime->rate);
91 goto out;
92 }
93
94 if (!priv->iio_active) {
95 ret = iio_channel_start_all_cb(priv->iio_cb);
96 if (!ret)
97 priv->iio_active = true;
98 else
99 dev_err(dai->dev, "%s: IIO channel start failed (%d)\n",
100 __func__, ret);
101 }
102
103out:
104 mutex_unlock(&priv->lock);
105
106 return ret;
107}
108
109static int stm32_adfsdm_set_sysclk(struct snd_soc_dai *dai, int clk_id,
110 unsigned int freq, int dir)
111{
112 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(dai);
113 ssize_t size;
114 char str_freq[10];
115
116 dev_dbg(dai->dev, "%s: Enter for freq %d\n", __func__, freq);
117
118
119
120 snprintf(str_freq, sizeof(str_freq), "%u\n", freq);
121 size = iio_write_channel_ext_info(priv->iio_ch, "spi_clk_freq",
122 str_freq, sizeof(str_freq));
123 if (size != sizeof(str_freq)) {
124 dev_err(dai->dev, "%s: Failed to set SPI clock\n",
125 __func__);
126 return -EINVAL;
127 }
128 return 0;
129}
130
131static const struct snd_soc_dai_ops stm32_adfsdm_dai_ops = {
132 .shutdown = stm32_adfsdm_shutdown,
133 .prepare = stm32_adfsdm_dai_prepare,
134 .set_sysclk = stm32_adfsdm_set_sysclk,
135};
136
137static const struct snd_soc_dai_driver stm32_adfsdm_dai = {
138 .capture = {
139 .channels_min = 1,
140 .channels_max = 1,
141 .formats = SNDRV_PCM_FMTBIT_S16_LE |
142 SNDRV_PCM_FMTBIT_S32_LE,
143 .rates = SNDRV_PCM_RATE_CONTINUOUS,
144 .rate_min = 8000,
145 .rate_max = 48000,
146 },
147 .ops = &stm32_adfsdm_dai_ops,
148};
149
150static const struct snd_soc_component_driver stm32_adfsdm_dai_component = {
151 .name = "stm32_dfsdm_audio",
152};
153
154static void stm32_memcpy_32to16(void *dest, const void *src, size_t n)
155{
156 unsigned int i = 0;
157 u16 *d = (u16 *)dest, *s = (u16 *)src;
158
159 s++;
160 for (i = n >> 1; i > 0; i--) {
161 *d++ = *s++;
162 s++;
163 }
164}
165
166static int stm32_afsdm_pcm_cb(const void *data, size_t size, void *private)
167{
168 struct stm32_adfsdm_priv *priv = private;
169 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(priv->substream);
170 u8 *pcm_buff = priv->pcm_buff;
171 u8 *src_buff = (u8 *)data;
172 unsigned int old_pos = priv->pos;
173 size_t buff_size = snd_pcm_lib_buffer_bytes(priv->substream);
174 size_t period_size = snd_pcm_lib_period_bytes(priv->substream);
175 size_t cur_size, src_size = size;
176 snd_pcm_format_t format = priv->substream->runtime->format;
177
178 if (format == SNDRV_PCM_FORMAT_S16_LE)
179 src_size >>= 1;
180 cur_size = src_size;
181
182 dev_dbg(rtd->dev, "%s: buff_add :%pK, pos = %d, size = %zu\n",
183 __func__, &pcm_buff[priv->pos], priv->pos, src_size);
184
185 if ((priv->pos + src_size) > buff_size) {
186 if (format == SNDRV_PCM_FORMAT_S16_LE)
187 stm32_memcpy_32to16(&pcm_buff[priv->pos], src_buff,
188 buff_size - priv->pos);
189 else
190 memcpy(&pcm_buff[priv->pos], src_buff,
191 buff_size - priv->pos);
192 cur_size -= buff_size - priv->pos;
193 priv->pos = 0;
194 }
195
196 if (format == SNDRV_PCM_FORMAT_S16_LE)
197 stm32_memcpy_32to16(&pcm_buff[priv->pos],
198 &src_buff[src_size - cur_size], cur_size);
199 else
200 memcpy(&pcm_buff[priv->pos], &src_buff[src_size - cur_size],
201 cur_size);
202
203 priv->pos = (priv->pos + cur_size) % buff_size;
204
205 if (cur_size != src_size || (old_pos && (old_pos % period_size < size)))
206 snd_pcm_period_elapsed(priv->substream);
207
208 return 0;
209}
210
211static int stm32_adfsdm_trigger(struct snd_soc_component *component,
212 struct snd_pcm_substream *substream, int cmd)
213{
214 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
215 struct stm32_adfsdm_priv *priv =
216 snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
217
218 switch (cmd) {
219 case SNDRV_PCM_TRIGGER_START:
220 case SNDRV_PCM_TRIGGER_RESUME:
221 priv->pos = 0;
222 return stm32_dfsdm_get_buff_cb(priv->iio_ch->indio_dev,
223 stm32_afsdm_pcm_cb, priv);
224 case SNDRV_PCM_TRIGGER_SUSPEND:
225 case SNDRV_PCM_TRIGGER_STOP:
226 return stm32_dfsdm_release_buff_cb(priv->iio_ch->indio_dev);
227 }
228
229 return -EINVAL;
230}
231
232static int stm32_adfsdm_pcm_open(struct snd_soc_component *component,
233 struct snd_pcm_substream *substream)
234{
235 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
236 struct stm32_adfsdm_priv *priv = snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
237 int ret;
238
239 ret = snd_soc_set_runtime_hwparams(substream, &stm32_adfsdm_pcm_hw);
240 if (!ret)
241 priv->substream = substream;
242
243 return ret;
244}
245
246static int stm32_adfsdm_pcm_close(struct snd_soc_component *component,
247 struct snd_pcm_substream *substream)
248{
249 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
250 struct stm32_adfsdm_priv *priv =
251 snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
252
253 priv->substream = NULL;
254
255 return 0;
256}
257
258static snd_pcm_uframes_t stm32_adfsdm_pcm_pointer(
259 struct snd_soc_component *component,
260 struct snd_pcm_substream *substream)
261{
262 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
263 struct stm32_adfsdm_priv *priv =
264 snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
265
266 return bytes_to_frames(substream->runtime, priv->pos);
267}
268
269static int stm32_adfsdm_pcm_hw_params(struct snd_soc_component *component,
270 struct snd_pcm_substream *substream,
271 struct snd_pcm_hw_params *params)
272{
273 struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
274 struct stm32_adfsdm_priv *priv =
275 snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
276
277 priv->pcm_buff = substream->runtime->dma_area;
278
279 return iio_channel_cb_set_buffer_watermark(priv->iio_cb,
280 params_period_size(params));
281}
282
283static int stm32_adfsdm_pcm_new(struct snd_soc_component *component,
284 struct snd_soc_pcm_runtime *rtd)
285{
286 struct snd_pcm *pcm = rtd->pcm;
287 struct stm32_adfsdm_priv *priv =
288 snd_soc_dai_get_drvdata(asoc_rtd_to_cpu(rtd, 0));
289 unsigned int size = DFSDM_MAX_PERIODS * DFSDM_MAX_PERIOD_SIZE;
290
291 snd_pcm_set_managed_buffer_all(pcm, SNDRV_DMA_TYPE_DEV,
292 priv->dev, size, size);
293 return 0;
294}
295
296static int stm32_adfsdm_dummy_cb(const void *data, void *private)
297{
298
299
300
301
302
303 return 0;
304}
305
306static struct snd_soc_component_driver stm32_adfsdm_soc_platform = {
307 .open = stm32_adfsdm_pcm_open,
308 .close = stm32_adfsdm_pcm_close,
309 .hw_params = stm32_adfsdm_pcm_hw_params,
310 .trigger = stm32_adfsdm_trigger,
311 .pointer = stm32_adfsdm_pcm_pointer,
312 .pcm_construct = stm32_adfsdm_pcm_new,
313};
314
315static const struct of_device_id stm32_adfsdm_of_match[] = {
316 {.compatible = "st,stm32h7-dfsdm-dai"},
317 {}
318};
319MODULE_DEVICE_TABLE(of, stm32_adfsdm_of_match);
320
321static int stm32_adfsdm_probe(struct platform_device *pdev)
322{
323 struct stm32_adfsdm_priv *priv;
324 struct snd_soc_component *component;
325 int ret;
326
327 priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
328 if (!priv)
329 return -ENOMEM;
330
331 priv->dev = &pdev->dev;
332 priv->dai_drv = stm32_adfsdm_dai;
333 mutex_init(&priv->lock);
334
335 dev_set_drvdata(&pdev->dev, priv);
336
337 ret = devm_snd_soc_register_component(&pdev->dev,
338 &stm32_adfsdm_dai_component,
339 &priv->dai_drv, 1);
340 if (ret < 0)
341 return ret;
342
343
344 priv->iio_ch = devm_iio_channel_get_all(&pdev->dev);
345 if (IS_ERR(priv->iio_ch))
346 return PTR_ERR(priv->iio_ch);
347
348 priv->iio_cb = iio_channel_get_all_cb(&pdev->dev, &stm32_adfsdm_dummy_cb, NULL);
349 if (IS_ERR(priv->iio_cb))
350 return PTR_ERR(priv->iio_cb);
351
352 component = devm_kzalloc(&pdev->dev, sizeof(*component), GFP_KERNEL);
353 if (!component)
354 return -ENOMEM;
355
356 ret = snd_soc_component_initialize(component,
357 &stm32_adfsdm_soc_platform,
358 &pdev->dev);
359 if (ret < 0)
360 return ret;
361#ifdef CONFIG_DEBUG_FS
362 component->debugfs_prefix = "pcm";
363#endif
364
365 ret = snd_soc_add_component(component, NULL, 0);
366 if (ret < 0)
367 dev_err(&pdev->dev, "%s: Failed to register PCM platform\n",
368 __func__);
369
370 return ret;
371}
372
373static int stm32_adfsdm_remove(struct platform_device *pdev)
374{
375 snd_soc_unregister_component(&pdev->dev);
376
377 return 0;
378}
379
380static struct platform_driver stm32_adfsdm_driver = {
381 .driver = {
382 .name = STM32_ADFSDM_DRV_NAME,
383 .of_match_table = stm32_adfsdm_of_match,
384 },
385 .probe = stm32_adfsdm_probe,
386 .remove = stm32_adfsdm_remove,
387};
388
389module_platform_driver(stm32_adfsdm_driver);
390
391MODULE_DESCRIPTION("stm32 DFSDM DAI driver");
392MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@st.com>");
393MODULE_LICENSE("GPL v2");
394MODULE_ALIAS("platform:" STM32_ADFSDM_DRV_NAME);
395
