xref: /openbmc/linux/sound/soc/sti/uniperif_reader.c (revision 8e694cd2)
1 /*
2  * Copyright (C) STMicroelectronics SA 2015
3  * Authors: Arnaud Pouliquen <arnaud.pouliquen@st.com>
4  *          for STMicroelectronics.
5  * License terms:  GNU General Public License (GPL), version 2
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/io.h>
11 
12 #include <sound/soc.h>
13 
14 #include "uniperif.h"
15 
16 /*
17  * Note: snd_pcm_hardware is linked to DMA controller but is declared here to
18  * integrate unireader capability in term of rate and supported channels
19  */
20 static const struct snd_pcm_hardware uni_reader_pcm_hw = {
21 	.info = SNDRV_PCM_INFO_INTERLEAVED | SNDRV_PCM_INFO_BLOCK_TRANSFER |
22 		SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_MMAP |
23 		SNDRV_PCM_INFO_MMAP_VALID,
24 	.formats = SNDRV_PCM_FMTBIT_S32_LE | SNDRV_PCM_FMTBIT_S16_LE,
25 
26 	.rates = SNDRV_PCM_RATE_CONTINUOUS,
27 	.rate_min = 8000,
28 	.rate_max = 96000,
29 
30 	.channels_min = 2,
31 	.channels_max = 8,
32 
33 	.periods_min = 2,
34 	.periods_max = 48,
35 
36 	.period_bytes_min = 128,
37 	.period_bytes_max = 64 * PAGE_SIZE,
38 	.buffer_bytes_max = 256 * PAGE_SIZE
39 };
40 
41 /*
42  * uni_reader_irq_handler
43  * In case of error audio stream is stopped; stop action is protected via PCM
44  * stream lock  to avoid race condition with trigger callback.
45  */
46 static irqreturn_t uni_reader_irq_handler(int irq, void *dev_id)
47 {
48 	irqreturn_t ret = IRQ_NONE;
49 	struct uniperif *reader = dev_id;
50 	unsigned int status;
51 
52 	if (reader->state == UNIPERIF_STATE_STOPPED) {
53 		/* Unexpected IRQ: do nothing */
54 		dev_warn(reader->dev, "unexpected IRQ ");
55 		return IRQ_HANDLED;
56 	}
57 
58 	/* Get interrupt status & clear them immediately */
59 	status = GET_UNIPERIF_ITS(reader);
60 	SET_UNIPERIF_ITS_BCLR(reader, status);
61 
62 	/* Check for fifo overflow error */
63 	if (unlikely(status & UNIPERIF_ITS_FIFO_ERROR_MASK(reader))) {
64 		dev_err(reader->dev, "FIFO error detected");
65 
66 		snd_pcm_stream_lock(reader->substream);
67 		snd_pcm_stop(reader->substream, SNDRV_PCM_STATE_XRUN);
68 		snd_pcm_stream_unlock(reader->substream);
69 
70 		return IRQ_HANDLED;
71 	}
72 
73 	return ret;
74 }
75 
76 static int uni_reader_prepare_pcm(struct snd_pcm_runtime *runtime,
77 				  struct uniperif *reader)
78 {
79 	int slot_width;
80 
81 	/* Force slot width to 32 in I2S mode */
82 	if ((reader->daifmt & SND_SOC_DAIFMT_FORMAT_MASK)
83 		== SND_SOC_DAIFMT_I2S) {
84 		slot_width = 32;
85 	} else {
86 		switch (runtime->format) {
87 		case SNDRV_PCM_FORMAT_S16_LE:
88 			slot_width = 16;
89 			break;
90 		default:
91 			slot_width = 32;
92 			break;
93 		}
94 	}
95 
96 	/* Number of bits per subframe (i.e one channel sample) on input. */
97 	switch (slot_width) {
98 	case 32:
99 		SET_UNIPERIF_I2S_FMT_NBIT_32(reader);
100 		SET_UNIPERIF_I2S_FMT_DATA_SIZE_32(reader);
101 		break;
102 	case 16:
103 		SET_UNIPERIF_I2S_FMT_NBIT_16(reader);
104 		SET_UNIPERIF_I2S_FMT_DATA_SIZE_16(reader);
105 		break;
106 	default:
107 		dev_err(reader->dev, "subframe format not supported");
108 		return -EINVAL;
109 	}
110 
111 	/* Configure data memory format */
112 	switch (runtime->format) {
113 	case SNDRV_PCM_FORMAT_S16_LE:
114 		/* One data word contains two samples */
115 		SET_UNIPERIF_CONFIG_MEM_FMT_16_16(reader);
116 		break;
117 
118 	case SNDRV_PCM_FORMAT_S32_LE:
119 		/*
120 		 * Actually "16 bits/0 bits" means "32/28/24/20/18/16 bits
121 		 * on the MSB then zeros (if less than 32 bytes)"...
122 		 */
123 		SET_UNIPERIF_CONFIG_MEM_FMT_16_0(reader);
124 		break;
125 
126 	default:
127 		dev_err(reader->dev, "format not supported");
128 		return -EINVAL;
129 	}
130 
131 	/* Number of channels must be even */
132 	if ((runtime->channels % 2) || (runtime->channels < 2) ||
133 	    (runtime->channels > 10)) {
134 		dev_err(reader->dev, "%s: invalid nb of channels", __func__);
135 		return -EINVAL;
136 	}
137 
138 	SET_UNIPERIF_I2S_FMT_NUM_CH(reader, runtime->channels / 2);
139 	SET_UNIPERIF_I2S_FMT_ORDER_MSB(reader);
140 
141 	return 0;
142 }
143 
144 static int uni_reader_prepare_tdm(struct snd_pcm_runtime *runtime,
145 				  struct uniperif *reader)
146 {
147 	int frame_size; /* user tdm frame size in bytes */
148 	/* default unip TDM_WORD_POS_X_Y */
149 	unsigned int word_pos[4] = {
150 		0x04060002, 0x0C0E080A, 0x14161012, 0x1C1E181A};
151 
152 	frame_size = sti_uniperiph_get_user_frame_size(runtime);
153 
154 	/* fix 16/0 format */
155 	SET_UNIPERIF_CONFIG_MEM_FMT_16_0(reader);
156 	SET_UNIPERIF_I2S_FMT_DATA_SIZE_32(reader);
157 
158 	/* number of words inserted on the TDM line */
159 	SET_UNIPERIF_I2S_FMT_NUM_CH(reader, frame_size / 4 / 2);
160 
161 	SET_UNIPERIF_I2S_FMT_ORDER_MSB(reader);
162 	SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
163 	SET_UNIPERIF_TDM_ENABLE_TDM_ENABLE(reader);
164 
165 	/*
166 	 * set the timeslots allocation for words in FIFO
167 	 *
168 	 * HW bug: (LSB word < MSB word) => this config is not possible
169 	 *         So if we want (LSB word < MSB) word, then it shall be
170 	 *         handled by user
171 	 */
172 	sti_uniperiph_get_tdm_word_pos(reader, word_pos);
173 	SET_UNIPERIF_TDM_WORD_POS(reader, 1_2, word_pos[WORD_1_2]);
174 	SET_UNIPERIF_TDM_WORD_POS(reader, 3_4, word_pos[WORD_3_4]);
175 	SET_UNIPERIF_TDM_WORD_POS(reader, 5_6, word_pos[WORD_5_6]);
176 	SET_UNIPERIF_TDM_WORD_POS(reader, 7_8, word_pos[WORD_7_8]);
177 
178 	return 0;
179 }
180 
181 static int uni_reader_prepare(struct snd_pcm_substream *substream,
182 			      struct snd_soc_dai *dai)
183 {
184 	struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
185 	struct uniperif *reader = priv->dai_data.uni;
186 	struct snd_pcm_runtime *runtime = substream->runtime;
187 	int transfer_size, trigger_limit, ret;
188 	int count = 10;
189 
190 	/* The reader should be stopped */
191 	if (reader->state != UNIPERIF_STATE_STOPPED) {
192 		dev_err(reader->dev, "%s: invalid reader state %d", __func__,
193 			reader->state);
194 		return -EINVAL;
195 	}
196 
197 	/* Calculate transfer size (in fifo cells and bytes) for frame count */
198 	if (reader->info->type == SND_ST_UNIPERIF_TYPE_TDM) {
199 		/* transfer size = unip frame size (in 32 bits FIFO cell) */
200 		transfer_size =
201 			sti_uniperiph_get_user_frame_size(runtime) / 4;
202 	} else {
203 		transfer_size = runtime->channels * UNIPERIF_FIFO_FRAMES;
204 	}
205 
206 	/* Calculate number of empty cells available before asserting DREQ */
207 	if (reader->ver < SND_ST_UNIPERIF_VERSION_UNI_PLR_TOP_1_0)
208 		trigger_limit = UNIPERIF_FIFO_SIZE - transfer_size;
209 	else
210 		/*
211 		 * Since SND_ST_UNIPERIF_VERSION_UNI_PLR_TOP_1_0
212 		 * FDMA_TRIGGER_LIMIT also controls when the state switches
213 		 * from OFF or STANDBY to AUDIO DATA.
214 		 */
215 		trigger_limit = transfer_size;
216 
217 	/* Trigger limit must be an even number */
218 	if ((!trigger_limit % 2) ||
219 	    (trigger_limit != 1 && transfer_size % 2) ||
220 	    (trigger_limit > UNIPERIF_CONFIG_DMA_TRIG_LIMIT_MASK(reader))) {
221 		dev_err(reader->dev, "invalid trigger limit %d", trigger_limit);
222 		return -EINVAL;
223 	}
224 
225 	SET_UNIPERIF_CONFIG_DMA_TRIG_LIMIT(reader, trigger_limit);
226 
227 	if (UNIPERIF_TYPE_IS_TDM(reader))
228 		ret = uni_reader_prepare_tdm(runtime, reader);
229 	else
230 		ret = uni_reader_prepare_pcm(runtime, reader);
231 	if (ret)
232 		return ret;
233 
234 	switch (reader->daifmt & SND_SOC_DAIFMT_FORMAT_MASK) {
235 	case SND_SOC_DAIFMT_I2S:
236 		SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
237 		SET_UNIPERIF_I2S_FMT_PADDING_I2S_MODE(reader);
238 		break;
239 	case SND_SOC_DAIFMT_LEFT_J:
240 		SET_UNIPERIF_I2S_FMT_ALIGN_LEFT(reader);
241 		SET_UNIPERIF_I2S_FMT_PADDING_SONY_MODE(reader);
242 		break;
243 	case SND_SOC_DAIFMT_RIGHT_J:
244 		SET_UNIPERIF_I2S_FMT_ALIGN_RIGHT(reader);
245 		SET_UNIPERIF_I2S_FMT_PADDING_SONY_MODE(reader);
246 		break;
247 	default:
248 		dev_err(reader->dev, "format not supported");
249 		return -EINVAL;
250 	}
251 
252 	/* Data clocking (changing) on the rising/falling edge */
253 	switch (reader->daifmt & SND_SOC_DAIFMT_INV_MASK) {
254 	case SND_SOC_DAIFMT_NB_NF:
255 		SET_UNIPERIF_I2S_FMT_LR_POL_LOW(reader);
256 		SET_UNIPERIF_I2S_FMT_SCLK_EDGE_RISING(reader);
257 		break;
258 	case SND_SOC_DAIFMT_NB_IF:
259 		SET_UNIPERIF_I2S_FMT_LR_POL_HIG(reader);
260 		SET_UNIPERIF_I2S_FMT_SCLK_EDGE_RISING(reader);
261 		break;
262 	case SND_SOC_DAIFMT_IB_NF:
263 		SET_UNIPERIF_I2S_FMT_LR_POL_LOW(reader);
264 		SET_UNIPERIF_I2S_FMT_SCLK_EDGE_FALLING(reader);
265 		break;
266 	case SND_SOC_DAIFMT_IB_IF:
267 		SET_UNIPERIF_I2S_FMT_LR_POL_HIG(reader);
268 		SET_UNIPERIF_I2S_FMT_SCLK_EDGE_FALLING(reader);
269 		break;
270 	}
271 
272 	/* Clear any pending interrupts */
273 	SET_UNIPERIF_ITS_BCLR(reader, GET_UNIPERIF_ITS(reader));
274 
275 	SET_UNIPERIF_I2S_FMT_NO_OF_SAMPLES_TO_READ(reader, 0);
276 
277 	/* Set the interrupt mask */
278 	SET_UNIPERIF_ITM_BSET_DMA_ERROR(reader);
279 	SET_UNIPERIF_ITM_BSET_FIFO_ERROR(reader);
280 	SET_UNIPERIF_ITM_BSET_MEM_BLK_READ(reader);
281 
282 	/* Enable underflow recovery interrupts */
283 	if (reader->info->underflow_enabled) {
284 		SET_UNIPERIF_ITM_BSET_UNDERFLOW_REC_DONE(reader);
285 		SET_UNIPERIF_ITM_BSET_UNDERFLOW_REC_FAILED(reader);
286 	}
287 
288 	/* Reset uniperipheral reader */
289 	SET_UNIPERIF_SOFT_RST_SOFT_RST(reader);
290 
291 	while (GET_UNIPERIF_SOFT_RST_SOFT_RST(reader)) {
292 		udelay(5);
293 		count--;
294 	}
295 	if (!count) {
296 		dev_err(reader->dev, "Failed to reset uniperif");
297 		return -EIO;
298 	}
299 
300 	return 0;
301 }
302 
303 static int uni_reader_start(struct uniperif *reader)
304 {
305 	/* The reader should be stopped */
306 	if (reader->state != UNIPERIF_STATE_STOPPED) {
307 		dev_err(reader->dev, "%s: invalid reader state", __func__);
308 		return -EINVAL;
309 	}
310 
311 	/* Enable reader interrupts (and clear possible stalled ones) */
312 	SET_UNIPERIF_ITS_BCLR_FIFO_ERROR(reader);
313 	SET_UNIPERIF_ITM_BSET_FIFO_ERROR(reader);
314 
315 	/* Launch the reader */
316 	SET_UNIPERIF_CTRL_OPERATION_PCM_DATA(reader);
317 
318 	/* Update state to started */
319 	reader->state = UNIPERIF_STATE_STARTED;
320 	return 0;
321 }
322 
323 static int uni_reader_stop(struct uniperif *reader)
324 {
325 	/* The reader should not be in stopped state */
326 	if (reader->state == UNIPERIF_STATE_STOPPED) {
327 		dev_err(reader->dev, "%s: invalid reader state", __func__);
328 		return -EINVAL;
329 	}
330 
331 	/* Turn the reader off */
332 	SET_UNIPERIF_CTRL_OPERATION_OFF(reader);
333 
334 	/* Disable interrupts */
335 	SET_UNIPERIF_ITM_BCLR(reader, GET_UNIPERIF_ITM(reader));
336 
337 	/* Update state to stopped and return */
338 	reader->state = UNIPERIF_STATE_STOPPED;
339 
340 	return 0;
341 }
342 
343 static int  uni_reader_trigger(struct snd_pcm_substream *substream,
344 			       int cmd, struct snd_soc_dai *dai)
345 {
346 	struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
347 	struct uniperif *reader = priv->dai_data.uni;
348 
349 	switch (cmd) {
350 	case SNDRV_PCM_TRIGGER_START:
351 		return  uni_reader_start(reader);
352 	case SNDRV_PCM_TRIGGER_STOP:
353 		return  uni_reader_stop(reader);
354 	default:
355 		return -EINVAL;
356 	}
357 }
358 
359 static int uni_reader_startup(struct snd_pcm_substream *substream,
360 			      struct snd_soc_dai *dai)
361 {
362 	struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
363 	struct uniperif *reader = priv->dai_data.uni;
364 	int ret;
365 
366 	if (!UNIPERIF_TYPE_IS_TDM(reader))
367 		return 0;
368 
369 	/* refine hw constraint in tdm mode */
370 	ret = snd_pcm_hw_rule_add(substream->runtime, 0,
371 				  SNDRV_PCM_HW_PARAM_CHANNELS,
372 				  sti_uniperiph_fix_tdm_chan,
373 				  reader, SNDRV_PCM_HW_PARAM_CHANNELS,
374 				  -1);
375 	if (ret < 0)
376 		return ret;
377 
378 	return snd_pcm_hw_rule_add(substream->runtime, 0,
379 				   SNDRV_PCM_HW_PARAM_FORMAT,
380 				   sti_uniperiph_fix_tdm_format,
381 				   reader, SNDRV_PCM_HW_PARAM_FORMAT,
382 				   -1);
383 }
384 
385 static void uni_reader_shutdown(struct snd_pcm_substream *substream,
386 				struct snd_soc_dai *dai)
387 {
388 	struct sti_uniperiph_data *priv = snd_soc_dai_get_drvdata(dai);
389 	struct uniperif *reader = priv->dai_data.uni;
390 
391 	if (reader->state != UNIPERIF_STATE_STOPPED) {
392 		/* Stop the reader */
393 		uni_reader_stop(reader);
394 	}
395 }
396 
397 static int uni_reader_parse_dt(struct platform_device *pdev,
398 			       struct uniperif *reader)
399 {
400 	struct uniperif_info *info;
401 	struct device_node *node = pdev->dev.of_node;
402 	const char *mode;
403 
404 	/* Allocate memory for the info structure */
405 	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
406 	if (!info)
407 		return -ENOMEM;
408 
409 	if (of_property_read_u32(node, "st,version", &reader->ver) ||
410 	    reader->ver == SND_ST_UNIPERIF_VERSION_UNKNOWN) {
411 		dev_err(&pdev->dev, "Unknown uniperipheral version ");
412 		return -EINVAL;
413 	}
414 
415 	/* Read the device mode property */
416 	if (of_property_read_string(node, "st,mode", &mode)) {
417 		dev_err(&pdev->dev, "uniperipheral mode not defined");
418 		return -EINVAL;
419 	}
420 
421 	if (strcasecmp(mode, "tdm") == 0)
422 		info->type = SND_ST_UNIPERIF_TYPE_TDM;
423 	else
424 		info->type = SND_ST_UNIPERIF_TYPE_PCM;
425 
426 	/* Save the info structure */
427 	reader->info = info;
428 
429 	return 0;
430 }
431 
432 static const struct snd_soc_dai_ops uni_reader_dai_ops = {
433 		.startup = uni_reader_startup,
434 		.shutdown = uni_reader_shutdown,
435 		.prepare = uni_reader_prepare,
436 		.trigger = uni_reader_trigger,
437 		.hw_params = sti_uniperiph_dai_hw_params,
438 		.set_fmt = sti_uniperiph_dai_set_fmt,
439 		.set_tdm_slot = sti_uniperiph_set_tdm_slot
440 };
441 
442 int uni_reader_init(struct platform_device *pdev,
443 		    struct uniperif *reader)
444 {
445 	int ret = 0;
446 
447 	reader->dev = &pdev->dev;
448 	reader->state = UNIPERIF_STATE_STOPPED;
449 	reader->dai_ops = &uni_reader_dai_ops;
450 
451 	ret = uni_reader_parse_dt(pdev, reader);
452 	if (ret < 0) {
453 		dev_err(reader->dev, "Failed to parse DeviceTree");
454 		return ret;
455 	}
456 
457 	if (UNIPERIF_TYPE_IS_TDM(reader))
458 		reader->hw = &uni_tdm_hw;
459 	else
460 		reader->hw = &uni_reader_pcm_hw;
461 
462 	ret = devm_request_irq(&pdev->dev, reader->irq,
463 			       uni_reader_irq_handler, IRQF_SHARED,
464 			       dev_name(&pdev->dev), reader);
465 	if (ret < 0) {
466 		dev_err(&pdev->dev, "Failed to request IRQ");
467 		return -EBUSY;
468 	}
469 
470 	return 0;
471 }
472 EXPORT_SYMBOL_GPL(uni_reader_init);
473