xref: /openbmc/linux/sound/soc/sti/uniperif_reader.c (revision bbb774d9)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) STMicroelectronics SA 2015
4  * Authors: Arnaud Pouliquen <arnaud.pouliquen@st.com>
5  *          for STMicroelectronics.
6  */
7 
8 #include <sound/soc.h>
9 
10 #include "uniperif.h"
11 
12 #define UNIPERIF_READER_I2S_IN 0 /* reader id connected to I2S/TDM TX bus */
13 /*
14  * Note: snd_pcm_hardware is linked to DMA controller but is declared here to
15  * integrate unireader capability in term of rate and supported channels
16  */
17 static const struct snd_pcm_hardware uni_reader_pcm_hw = {
18 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
19 		SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_MMAP |
20 		SNDRV_PCM_INFO_MMAP_VALID,
21 	.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S16_LE,
22 
23 	.rates = SNDRV_PCM_RATE_CONTINUOUS,
24 	.rate_min = 8000,
25 	.rate_max = 96000,
26 
27 	.channels_min = 2,
28 	.channels_max = 8,
29 
30 	.periods_min = 2,
31 	.periods_max = 48,
32 
33 	.period_bytes_min = 128,
34 	.period_bytes_max = 64 * PAGE_SIZE,
35 	.buffer_bytes_max = 256 * PAGE_SIZE
36 };
37 
38 /*
39  * uni_reader_irq_handler
40  * In case of error audio stream is stopped; stop action is protected via PCM
41  * stream lock  to avoid race condition with trigger callback.
42  */
43 static irqreturn_t uni_reader_irq_handler(int irq, void *dev_id)
44 {
45 	irqreturn_t ret = IRQ_NONE;
46 	struct uniperif *reader = dev_id;
47 	unsigned int status;
48 
49 	spin_lock(&reader->irq_lock);
50 	if (!reader->substream)
51 		goto irq_spin_unlock;
52 
53 	snd_pcm_stream_lock(reader->substream);
54 	if (reader->state == UNIPERIF_STATE_STOPPED) {
55 		/* Unexpected IRQ: do nothing */
56 		dev_warn(reader->dev, "unexpected IRQ\n");
57 		goto stream_unlock;
58 	}
59 
60 	/* Get interrupt status & clear them immediately */
61 	status = GET_UNIPERIF_ITS(reader);
62 	SET_UNIPERIF_ITS_BCLR(reader, status);
63 
64 	/* Check for fifo overflow error */
65 	if (unlikely(status & UNIPERIF_ITS_FIFO_ERROR_MASK(reader))) {
66 		dev_err(reader->dev, "FIFO error detected\n");
67 
68 		snd_pcm_stop(reader->substream, SNDRV_PCM_STATE_XRUN);
69 
70 		ret = IRQ_HANDLED;
71 	}
72 
73 stream_unlock:
74 	snd_pcm_stream_unlock(reader->substream);
75 irq_spin_unlock:
76 	spin_unlock(&reader->irq_lock);
77 
78 	return ret;
79 }
80 
81 static int uni_reader_prepare_pcm(struct snd_pcm_runtime *runtime,
82 				  struct uniperif *reader)
83 {
84 	int slot_width;
85 
86 	/* Force slot width to 32 in I2S mode */
87 	if ((reader->daifmt & SND_SOC_DAIFMT_FORMAT_MASK)
88 		== SND_SOC_DAIFMT_I2S) {
89 		slot_width = 32;
90 	} else {
91 		switch (runtime->format) {
92 		case SNDRV_PCM_FORMAT_S16_LE:
93 			slot_width = 16;
94 			break;
95 		default:
96 			slot_width = 32;
97 			break;
98 		}
99 	}
100 
101 	/* Number of bits per subframe (i.e one channel sample) on input. */
102 	switch (slot_width) {
103 	case 32:
104 		SET_UNIPERIF_I2S_FMT_NBIT_32(reader);
105 		SET_UNIPERIF_I2S_FMT_DATA_SIZE_32(reader);
106 		break;
107 	case 16:
108 		SET_UNIPERIF_I2S_FMT_NBIT_16(reader);
109 		SET_UNIPERIF_I2S_FMT_DATA_SIZE_16(reader);
110 		break;
111 	default:
112 		dev_err(reader->dev, "subframe format not supported\n");
113 		return -EINVAL;
114 	}
115 
116 	/* Configure data memory format */
117 	switch (runtime->format) {
118 	case SNDRV_PCM_FORMAT_S16_LE:
119 		/* One data word contains two samples */
120 		SET_UNIPERIF_CONFIG_MEM_FMT_16_16(reader);
121 		break;
122 
123 	case SNDRV_PCM_FORMAT_S32_LE:
124 		/*
125 		 * Actually "16 bits/0 bits" means "32/28/24/20/18/16 bits
126 		 * on the MSB then zeros (if less than 32 bytes)"...
127 		 */
128 		SET_UNIPERIF_CONFIG_MEM_FMT_16_0(reader);
129 		break;
130 
131 	default:
132 		dev_err(reader->dev, "format not supported\n");
133 		return -EINVAL;
134 	}
135 
136 	/* Number of channels must be even */
137 	if ((runtime->channels % 2) || (runtime->channels < 2) ||
138 	    (runtime->channels > 10)) {
139 		dev_err(reader->dev, "%s: invalid nb of channels\n", __func__);
140 		return -EINVAL;
141 	}
142 
143 	SET_UNIPERIF_I2S_FMT_NUM_CH(reader, runtime->channels / 2);
144 	SET_UNIPERIF_I2S_FMT_ORDER_MSB(reader);
145 
146 	return 0;
147 }
148 
149 static int uni_reader_prepare_tdm(struct snd_pcm_runtime *runtime,
150 				  struct uniperif *reader)
151 {
152 	int frame_size; /* user tdm frame size in bytes */
153 	/* default unip TDM_WORD_POS_X_Y */
154 	unsigned int word_pos[4] = {
155 		0x04060002, 0x0C0E080A, 0x14161012, 0x1C1E181A};
156 
157 	frame_size = sti_uniperiph_get_user_frame_size(runtime);
158 
159 	/* fix 16/0 format */
160 	SET_UNIPERIF_CONFIG_MEM_FMT_16_0(reader);
161 	SET_UNIPERIF_I2S_FMT_DATA_SIZE_32(reader);
162 
163 	/* number of words inserted on the TDM line */
164 	SET_UNIPERIF_I2S_FMT_NUM_CH(reader, frame_size / 4 / 2);
165 
166 	SET_UNIPERIF_I2S_FMT_ORDER_MSB(reader);
167 	SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
168 	SET_UNIPERIF_TDM_ENABLE_TDM_ENABLE(reader);
169 
170 	/*
171 	 * set the timeslots allocation for words in FIFO
172 	 *
173 	 * HW bug: (LSB word < MSB word) => this config is not possible
174 	 *         So if we want (LSB word < MSB) word, then it shall be
175 	 *         handled by user
176 	 */
177 	sti_uniperiph_get_tdm_word_pos(reader, word_pos);
178 	SET_UNIPERIF_TDM_WORD_POS(reader, 1_2, word_pos[WORD_1_2]);
179 	SET_UNIPERIF_TDM_WORD_POS(reader, 3_4, word_pos[WORD_3_4]);
180 	SET_UNIPERIF_TDM_WORD_POS(reader, 5_6, word_pos[WORD_5_6]);
181 	SET_UNIPERIF_TDM_WORD_POS(reader, 7_8, word_pos[WORD_7_8]);
182 
183 	return 0;
184 }
185 
186 static int uni_reader_prepare(struct snd_pcm_substream *substream,
187 			      struct snd_soc_dai *dai)
188 {
189 	struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
190 	struct uniperif *reader = priv->dai_data.uni;
191 	struct snd_pcm_runtime *runtime = substream->runtime;
192 	int transfer_size, trigger_limit, ret;
193 
194 	/* The reader should be stopped */
195 	if (reader->state != UNIPERIF_STATE_STOPPED) {
196 		dev_err(reader->dev, "%s: invalid reader state %d\n", __func__,
197 			reader->state);
198 		return -EINVAL;
199 	}
200 
201 	/* Calculate transfer size (in fifo cells and bytes) for frame count */
202 	if (reader->type == SND_ST_UNIPERIF_TYPE_TDM) {
203 		/* transfer size = unip frame size (in 32 bits FIFO cell) */
204 		transfer_size =
205 			sti_uniperiph_get_user_frame_size(runtime) / 4;
206 	} else {
207 		transfer_size = runtime->channels * UNIPERIF_FIFO_FRAMES;
208 	}
209 
210 	/* Calculate number of empty cells available before asserting DREQ */
211 	if (reader->ver < SND_ST_UNIPERIF_VERSION_UNI_PLR_TOP_1_0)
212 		trigger_limit = UNIPERIF_FIFO_SIZE - transfer_size;
213 	else
214 		/*
215 		 * Since SND_ST_UNIPERIF_VERSION_UNI_PLR_TOP_1_0
216 		 * FDMA_TRIGGER_LIMIT also controls when the state switches
217 		 * from OFF or STANDBY to AUDIO DATA.
218 		 */
219 		trigger_limit = transfer_size;
220 
221 	/* Trigger limit must be an even number */
222 	if ((!trigger_limit % 2) ||
223 	    (trigger_limit != 1 && transfer_size % 2) ||
224 	    (trigger_limit > UNIPERIF_CONFIG_DMA_TRIG_LIMIT_MASK(reader))) {
225 		dev_err(reader->dev, "invalid trigger limit %d\n",
226 			trigger_limit);
227 		return -EINVAL;
228 	}
229 
230 	SET_UNIPERIF_CONFIG_DMA_TRIG_LIMIT(reader, trigger_limit);
231 
232 	if (UNIPERIF_TYPE_IS_TDM(reader))
233 		ret = uni_reader_prepare_tdm(runtime, reader);
234 	else
235 		ret = uni_reader_prepare_pcm(runtime, reader);
236 	if (ret)
237 		return ret;
238 
239 	switch (reader->daifmt & SND_SOC_DAIFMT_FORMAT_MASK) {
240 	case SND_SOC_DAIFMT_I2S:
241 		SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
242 		SET_UNIPERIF_I2S_FMT_PADDING_I2S_MODE(reader);
243 		break;
244 	case SND_SOC_DAIFMT_LEFT_J:
245 		SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
246 		SET_UNIPERIF_I2S_FMT_PADDING_SONY_MODE(reader);
247 		break;
248 	case SND_SOC_DAIFMT_RIGHT_J:
249 		SET_UNIPERIF_I2S_FMT_ALIGN_RIGHT(reader);
250 		SET_UNIPERIF_I2S_FMT_PADDING_SONY_MODE(reader);
251 		break;
252 	default:
253 		dev_err(reader->dev, "format not supported\n");
254 		return -EINVAL;
255 	}
256 
257 	/* Data clocking (changing) on the rising/falling edge */
258 	switch (reader->daifmt & SND_SOC_DAIFMT_INV_MASK) {
259 	case SND_SOC_DAIFMT_NB_NF:
260 		SET_UNIPERIF_I2S_FMT_LR_POL_LOW(reader);
261 		SET_UNIPERIF_I2S_FMT_SCLK_EDGE_RISING(reader);
262 		break;
263 	case SND_SOC_DAIFMT_NB_IF:
264 		SET_UNIPERIF_I2S_FMT_LR_POL_HIG(reader);
265 		SET_UNIPERIF_I2S_FMT_SCLK_EDGE_RISING(reader);
266 		break;
267 	case SND_SOC_DAIFMT_IB_NF:
268 		SET_UNIPERIF_I2S_FMT_LR_POL_LOW(reader);
269 		SET_UNIPERIF_I2S_FMT_SCLK_EDGE_FALLING(reader);
270 		break;
271 	case SND_SOC_DAIFMT_IB_IF:
272 		SET_UNIPERIF_I2S_FMT_LR_POL_HIG(reader);
273 		SET_UNIPERIF_I2S_FMT_SCLK_EDGE_FALLING(reader);
274 		break;
275 	}
276 
277 	/* Clear any pending interrupts */
278 	SET_UNIPERIF_ITS_BCLR(reader, GET_UNIPERIF_ITS(reader));
279 
280 	SET_UNIPERIF_I2S_FMT_NO_OF_SAMPLES_TO_READ(reader, 0);
281 
282 	/* Set the interrupt mask */
283 	SET_UNIPERIF_ITM_BSET_DMA_ERROR(reader);
284 	SET_UNIPERIF_ITM_BSET_FIFO_ERROR(reader);
285 	SET_UNIPERIF_ITM_BSET_MEM_BLK_READ(reader);
286 
287 	/* Enable underflow recovery interrupts */
288 	if (reader->underflow_enabled) {
289 		SET_UNIPERIF_ITM_BSET_UNDERFLOW_REC_DONE(reader);
290 		SET_UNIPERIF_ITM_BSET_UNDERFLOW_REC_FAILED(reader);
291 	}
292 
293 	/* Reset uniperipheral reader */
294 	return sti_uniperiph_reset(reader);
295 }
296 
297 static int uni_reader_start(struct uniperif *reader)
298 {
299 	/* The reader should be stopped */
300 	if (reader->state != UNIPERIF_STATE_STOPPED) {
301 		dev_err(reader->dev, "%s: invalid reader state\n", __func__);
302 		return -EINVAL;
303 	}
304 
305 	/* Enable reader interrupts (and clear possible stalled ones) */
306 	SET_UNIPERIF_ITS_BCLR_FIFO_ERROR(reader);
307 	SET_UNIPERIF_ITM_BSET_FIFO_ERROR(reader);
308 
309 	/* Launch the reader */
310 	SET_UNIPERIF_CTRL_OPERATION_PCM_DATA(reader);
311 
312 	/* Update state to started */
313 	reader->state = UNIPERIF_STATE_STARTED;
314 	return 0;
315 }
316 
317 static int uni_reader_stop(struct uniperif *reader)
318 {
319 	/* The reader should not be in stopped state */
320 	if (reader->state == UNIPERIF_STATE_STOPPED) {
321 		dev_err(reader->dev, "%s: invalid reader state\n", __func__);
322 		return -EINVAL;
323 	}
324 
325 	/* Turn the reader off */
326 	SET_UNIPERIF_CTRL_OPERATION_OFF(reader);
327 
328 	/* Disable interrupts */
329 	SET_UNIPERIF_ITM_BCLR(reader, GET_UNIPERIF_ITM(reader));
330 
331 	/* Update state to stopped and return */
332 	reader->state = UNIPERIF_STATE_STOPPED;
333 
334 	return 0;
335 }
336 
337 static int  uni_reader_trigger(struct snd_pcm_substream *substream,
338 			       int cmd, struct snd_soc_dai *dai)
339 {
340 	struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
341 	struct uniperif *reader = priv->dai_data.uni;
342 
343 	switch (cmd) {
344 	case SNDRV_PCM_TRIGGER_START:
345 		return  uni_reader_start(reader);
346 	case SNDRV_PCM_TRIGGER_STOP:
347 		return  uni_reader_stop(reader);
348 	default:
349 		return -EINVAL;
350 	}
351 }
352 
353 static int uni_reader_startup(struct snd_pcm_substream *substream,
354 			      struct snd_soc_dai *dai)
355 {
356 	struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
357 	struct uniperif *reader = priv->dai_data.uni;
358 	unsigned long flags;
359 	int ret;
360 
361 	spin_lock_irqsave(&reader->irq_lock, flags);
362 	reader->substream = substream;
363 	spin_unlock_irqrestore(&reader->irq_lock, flags);
364 
365 	if (!UNIPERIF_TYPE_IS_TDM(reader))
366 		return 0;
367 
368 	/* refine hw constraint in tdm mode */
369 	ret = snd_pcm_hw_rule_add(substream->runtime, 0,
370 				  SNDRV_PCM_HW_PARAM_CHANNELS,
371 				  sti_uniperiph_fix_tdm_chan,
372 				  reader, SNDRV_PCM_HW_PARAM_CHANNELS,
373 				  -1);
374 	if (ret < 0)
375 		return ret;
376 
377 	return snd_pcm_hw_rule_add(substream->runtime, 0,
378 				   SNDRV_PCM_HW_PARAM_FORMAT,
379 				   sti_uniperiph_fix_tdm_format,
380 				   reader, SNDRV_PCM_HW_PARAM_FORMAT,
381 				   -1);
382 }
383 
384 static void uni_reader_shutdown(struct snd_pcm_substream *substream,
385 				struct snd_soc_dai *dai)
386 {
387 	struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
388 	struct uniperif *reader = priv->dai_data.uni;
389 	unsigned long flags;
390 
391 	spin_lock_irqsave(&reader->irq_lock, flags);
392 	if (reader->state != UNIPERIF_STATE_STOPPED) {
393 		/* Stop the reader */
394 		uni_reader_stop(reader);
395 	}
396 	reader->substream = NULL;
397 	spin_unlock_irqrestore(&reader->irq_lock, flags);
398 }
399 
400 static const struct snd_soc_dai_ops uni_reader_dai_ops = {
401 		.startup = uni_reader_startup,
402 		.shutdown = uni_reader_shutdown,
403 		.prepare = uni_reader_prepare,
404 		.trigger = uni_reader_trigger,
405 		.hw_params = sti_uniperiph_dai_hw_params,
406 		.set_fmt = sti_uniperiph_dai_set_fmt,
407 		.set_tdm_slot = sti_uniperiph_set_tdm_slot
408 };
409 
410 int uni_reader_init(struct platform_device *pdev,
411 		    struct uniperif *reader)
412 {
413 	int ret = 0;
414 
415 	reader->dev = &pdev->dev;
416 	reader->state = UNIPERIF_STATE_STOPPED;
417 	reader->dai_ops = &uni_reader_dai_ops;
418 
419 	if (UNIPERIF_TYPE_IS_TDM(reader))
420 		reader->hw = &uni_tdm_hw;
421 	else
422 		reader->hw = &uni_reader_pcm_hw;
423 
424 	ret = devm_request_irq(&pdev->dev, reader->irq,
425 			       uni_reader_irq_handler, IRQF_SHARED,
426 			       dev_name(&pdev->dev), reader);
427 	if (ret < 0) {
428 		dev_err(&pdev->dev, "Failed to request IRQ\n");
429 		return -EBUSY;
430 	}
431 
432 	spin_lock_init(&reader->irq_lock);
433 
434 	return 0;
435 }
436 EXPORT_SYMBOL_GPL(uni_reader_init);
437