xref: /openbmc/linux/sound/soc/codecs/rt5514-spi.c (revision 3ddc8b84)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * rt5514-spi.c  --  RT5514 SPI driver
4  *
5  * Copyright 2015 Realtek Semiconductor Corp.
6  * Author: Oder Chiou <oder_chiou@realtek.com>
7  */
8 
9 #include <linux/module.h>
10 #include <linux/input.h>
11 #include <linux/spi/spi.h>
12 #include <linux/device.h>
13 #include <linux/init.h>
14 #include <linux/delay.h>
15 #include <linux/interrupt.h>
16 #include <linux/irq.h>
17 #include <linux/slab.h>
18 #include <linux/sched.h>
19 #include <linux/uaccess.h>
20 #include <linux/regulator/consumer.h>
21 #include <linux/pm_qos.h>
22 #include <linux/sysfs.h>
23 #include <linux/clk.h>
24 #include <sound/core.h>
25 #include <sound/pcm.h>
26 #include <sound/pcm_params.h>
27 #include <sound/soc.h>
28 #include <sound/soc-dapm.h>
29 #include <sound/initval.h>
30 #include <sound/tlv.h>
31 
32 #include "rt5514-spi.h"
33 
34 #define DRV_NAME "rt5514-spi"
35 
36 static struct spi_device *rt5514_spi;
37 
38 struct rt5514_dsp {
39 	struct device *dev;
40 	struct delayed_work copy_work;
41 	struct mutex dma_lock;
42 	struct snd_pcm_substream *substream;
43 	unsigned int buf_base, buf_limit, buf_rp;
44 	size_t buf_size, get_size, dma_offset;
45 };
46 
47 static const struct snd_pcm_hardware rt5514_spi_pcm_hardware = {
48 	.info			= SNDRV_PCM_INFO_MMAP |
49 				  SNDRV_PCM_INFO_MMAP_VALID |
50 				  SNDRV_PCM_INFO_INTERLEAVED,
51 	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
52 	.period_bytes_min	= PAGE_SIZE,
53 	.period_bytes_max	= 0x20000 / 8,
54 	.periods_min		= 8,
55 	.periods_max		= 8,
56 	.channels_min		= 1,
57 	.channels_max		= 1,
58 	.buffer_bytes_max	= 0x20000,
59 };
60 
61 static struct snd_soc_dai_driver rt5514_spi_dai = {
62 	.name = "rt5514-dsp-cpu-dai",
63 	.id = 0,
64 	.capture = {
65 		.stream_name = "DSP Capture",
66 		.channels_min = 1,
67 		.channels_max = 1,
68 		.rates = SNDRV_PCM_RATE_16000,
69 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
70 	},
71 };
72 
73 static void rt5514_spi_copy_work(struct work_struct *work)
74 {
75 	struct rt5514_dsp *rt5514_dsp =
76 		container_of(work, struct rt5514_dsp, copy_work.work);
77 	struct snd_pcm_runtime *runtime;
78 	size_t period_bytes, truncated_bytes = 0;
79 	unsigned int cur_wp, remain_data;
80 	u8 buf[8];
81 
82 	mutex_lock(&rt5514_dsp->dma_lock);
83 	if (!rt5514_dsp->substream) {
84 		dev_err(rt5514_dsp->dev, "No pcm substream\n");
85 		goto done;
86 	}
87 
88 	runtime = rt5514_dsp->substream->runtime;
89 	period_bytes = snd_pcm_lib_period_bytes(rt5514_dsp->substream);
90 	if (!period_bytes) {
91 		schedule_delayed_work(&rt5514_dsp->copy_work, 5);
92 		goto done;
93 	}
94 
95 	if (rt5514_dsp->buf_size % period_bytes)
96 		rt5514_dsp->buf_size = (rt5514_dsp->buf_size / period_bytes) *
97 			period_bytes;
98 
99 	if (rt5514_dsp->get_size >= rt5514_dsp->buf_size) {
100 		rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
101 			sizeof(buf));
102 		cur_wp = buf[0] | buf[1] << 8 | buf[2] << 16 |
103 					buf[3] << 24;
104 
105 		if (cur_wp >= rt5514_dsp->buf_rp)
106 			remain_data = (cur_wp - rt5514_dsp->buf_rp);
107 		else
108 			remain_data =
109 				(rt5514_dsp->buf_limit - rt5514_dsp->buf_rp) +
110 				(cur_wp - rt5514_dsp->buf_base);
111 
112 		if (remain_data < period_bytes) {
113 			schedule_delayed_work(&rt5514_dsp->copy_work, 5);
114 			goto done;
115 		}
116 	}
117 
118 	if (rt5514_dsp->buf_rp + period_bytes <= rt5514_dsp->buf_limit) {
119 		rt5514_spi_burst_read(rt5514_dsp->buf_rp,
120 			runtime->dma_area + rt5514_dsp->dma_offset,
121 			period_bytes);
122 
123 		if (rt5514_dsp->buf_rp + period_bytes == rt5514_dsp->buf_limit)
124 			rt5514_dsp->buf_rp = rt5514_dsp->buf_base;
125 		else
126 			rt5514_dsp->buf_rp += period_bytes;
127 	} else {
128 		truncated_bytes = rt5514_dsp->buf_limit - rt5514_dsp->buf_rp;
129 		rt5514_spi_burst_read(rt5514_dsp->buf_rp,
130 			runtime->dma_area + rt5514_dsp->dma_offset,
131 			truncated_bytes);
132 
133 		rt5514_spi_burst_read(rt5514_dsp->buf_base,
134 			runtime->dma_area + rt5514_dsp->dma_offset +
135 			truncated_bytes, period_bytes - truncated_bytes);
136 
137 		rt5514_dsp->buf_rp = rt5514_dsp->buf_base + period_bytes -
138 			truncated_bytes;
139 	}
140 
141 	rt5514_dsp->get_size += period_bytes;
142 	rt5514_dsp->dma_offset += period_bytes;
143 	if (rt5514_dsp->dma_offset >= runtime->dma_bytes)
144 		rt5514_dsp->dma_offset = 0;
145 
146 	snd_pcm_period_elapsed(rt5514_dsp->substream);
147 
148 	schedule_delayed_work(&rt5514_dsp->copy_work, 5);
149 
150 done:
151 	mutex_unlock(&rt5514_dsp->dma_lock);
152 }
153 
154 static void rt5514_schedule_copy(struct rt5514_dsp *rt5514_dsp)
155 {
156 	u8 buf[8];
157 
158 	if (!rt5514_dsp->substream)
159 		return;
160 
161 	rt5514_dsp->get_size = 0;
162 
163 	/**
164 	 * The address area x1800XXXX is the register address, and it cannot
165 	 * support spi burst read perfectly. So we use the spi burst read
166 	 * individually to make sure the data correctly.
167 	 */
168 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_BASE, (u8 *)&buf,
169 		sizeof(buf));
170 	rt5514_dsp->buf_base = buf[0] | buf[1] << 8 | buf[2] << 16 |
171 				buf[3] << 24;
172 
173 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_LIMIT, (u8 *)&buf,
174 		sizeof(buf));
175 	rt5514_dsp->buf_limit = buf[0] | buf[1] << 8 | buf[2] << 16 |
176 				buf[3] << 24;
177 
178 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
179 		sizeof(buf));
180 	rt5514_dsp->buf_rp = buf[0] | buf[1] << 8 | buf[2] << 16 |
181 				buf[3] << 24;
182 
183 	if (rt5514_dsp->buf_rp % 8)
184 		rt5514_dsp->buf_rp = (rt5514_dsp->buf_rp / 8) * 8;
185 
186 	rt5514_dsp->buf_size = rt5514_dsp->buf_limit - rt5514_dsp->buf_base;
187 
188 	if (rt5514_dsp->buf_base && rt5514_dsp->buf_limit &&
189 		rt5514_dsp->buf_rp && rt5514_dsp->buf_size)
190 		schedule_delayed_work(&rt5514_dsp->copy_work, 0);
191 }
192 
193 static irqreturn_t rt5514_spi_irq(int irq, void *data)
194 {
195 	struct rt5514_dsp *rt5514_dsp = data;
196 
197 	rt5514_schedule_copy(rt5514_dsp);
198 
199 	return IRQ_HANDLED;
200 }
201 
202 /* PCM for streaming audio from the DSP buffer */
203 static int rt5514_spi_pcm_open(struct snd_soc_component *component,
204 			       struct snd_pcm_substream *substream)
205 {
206 	snd_soc_set_runtime_hwparams(substream, &rt5514_spi_pcm_hardware);
207 
208 	return 0;
209 }
210 
211 static int rt5514_spi_hw_params(struct snd_soc_component *component,
212 				struct snd_pcm_substream *substream,
213 				struct snd_pcm_hw_params *hw_params)
214 {
215 	struct rt5514_dsp *rt5514_dsp =
216 		snd_soc_component_get_drvdata(component);
217 	u8 buf[8];
218 
219 	mutex_lock(&rt5514_dsp->dma_lock);
220 	rt5514_dsp->substream = substream;
221 	rt5514_dsp->dma_offset = 0;
222 
223 	/* Read IRQ status and schedule copy accordingly. */
224 	rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf, sizeof(buf));
225 	if (buf[0] & RT5514_IRQ_STATUS_BIT)
226 		rt5514_schedule_copy(rt5514_dsp);
227 
228 	mutex_unlock(&rt5514_dsp->dma_lock);
229 
230 	return 0;
231 }
232 
233 static int rt5514_spi_hw_free(struct snd_soc_component *component,
234 			      struct snd_pcm_substream *substream)
235 {
236 	struct rt5514_dsp *rt5514_dsp =
237 		snd_soc_component_get_drvdata(component);
238 
239 	mutex_lock(&rt5514_dsp->dma_lock);
240 	rt5514_dsp->substream = NULL;
241 	mutex_unlock(&rt5514_dsp->dma_lock);
242 
243 	cancel_delayed_work_sync(&rt5514_dsp->copy_work);
244 
245 	return 0;
246 }
247 
248 static snd_pcm_uframes_t rt5514_spi_pcm_pointer(
249 		struct snd_soc_component *component,
250 		struct snd_pcm_substream *substream)
251 {
252 	struct snd_pcm_runtime *runtime = substream->runtime;
253 	struct rt5514_dsp *rt5514_dsp =
254 		snd_soc_component_get_drvdata(component);
255 
256 	return bytes_to_frames(runtime, rt5514_dsp->dma_offset);
257 }
258 
259 
260 static int rt5514_spi_pcm_probe(struct snd_soc_component *component)
261 {
262 	struct rt5514_dsp *rt5514_dsp;
263 	int ret;
264 
265 	rt5514_dsp = devm_kzalloc(component->dev, sizeof(*rt5514_dsp),
266 			GFP_KERNEL);
267 	if (!rt5514_dsp)
268 		return -ENOMEM;
269 
270 	rt5514_dsp->dev = &rt5514_spi->dev;
271 	mutex_init(&rt5514_dsp->dma_lock);
272 	INIT_DELAYED_WORK(&rt5514_dsp->copy_work, rt5514_spi_copy_work);
273 	snd_soc_component_set_drvdata(component, rt5514_dsp);
274 
275 	if (rt5514_spi->irq) {
276 		ret = devm_request_threaded_irq(&rt5514_spi->dev,
277 			rt5514_spi->irq, NULL, rt5514_spi_irq,
278 			IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rt5514-spi",
279 			rt5514_dsp);
280 		if (ret)
281 			dev_err(&rt5514_spi->dev,
282 				"%s Failed to reguest IRQ: %d\n", __func__,
283 				ret);
284 		else
285 			device_init_wakeup(rt5514_dsp->dev, true);
286 	}
287 
288 	return 0;
289 }
290 
291 static int rt5514_spi_pcm_new(struct snd_soc_component *component,
292 			      struct snd_soc_pcm_runtime *rtd)
293 {
294 	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_VMALLOC,
295 				       NULL, 0, 0);
296 	return 0;
297 }
298 
299 static const struct snd_soc_component_driver rt5514_spi_component = {
300 	.name			= DRV_NAME,
301 	.probe			= rt5514_spi_pcm_probe,
302 	.open			= rt5514_spi_pcm_open,
303 	.hw_params		= rt5514_spi_hw_params,
304 	.hw_free		= rt5514_spi_hw_free,
305 	.pointer		= rt5514_spi_pcm_pointer,
306 	.pcm_construct		= rt5514_spi_pcm_new,
307 	.legacy_dai_naming	= 1,
308 };
309 
310 /**
311  * rt5514_spi_burst_read - Read data from SPI by rt5514 address.
312  * @addr: Start address.
313  * @rxbuf: Data Buffer for reading.
314  * @len: Data length, it must be a multiple of 8.
315  *
316  *
317  * Returns true for success.
318  */
319 int rt5514_spi_burst_read(unsigned int addr, u8 *rxbuf, size_t len)
320 {
321 	u8 spi_cmd = RT5514_SPI_CMD_BURST_READ;
322 	int status;
323 	u8 write_buf[8];
324 	unsigned int i, end, offset = 0;
325 
326 	struct spi_message message;
327 	struct spi_transfer x[3];
328 
329 	while (offset < len) {
330 		if (offset + RT5514_SPI_BUF_LEN <= len)
331 			end = RT5514_SPI_BUF_LEN;
332 		else
333 			end = len % RT5514_SPI_BUF_LEN;
334 
335 		write_buf[0] = spi_cmd;
336 		write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
337 		write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
338 		write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
339 		write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
340 
341 		spi_message_init(&message);
342 		memset(x, 0, sizeof(x));
343 
344 		x[0].len = 5;
345 		x[0].tx_buf = write_buf;
346 		spi_message_add_tail(&x[0], &message);
347 
348 		x[1].len = 4;
349 		x[1].tx_buf = write_buf;
350 		spi_message_add_tail(&x[1], &message);
351 
352 		x[2].len = end;
353 		x[2].rx_buf = rxbuf + offset;
354 		spi_message_add_tail(&x[2], &message);
355 
356 		status = spi_sync(rt5514_spi, &message);
357 
358 		if (status)
359 			return false;
360 
361 		offset += RT5514_SPI_BUF_LEN;
362 	}
363 
364 	for (i = 0; i < len; i += 8) {
365 		write_buf[0] = rxbuf[i + 0];
366 		write_buf[1] = rxbuf[i + 1];
367 		write_buf[2] = rxbuf[i + 2];
368 		write_buf[3] = rxbuf[i + 3];
369 		write_buf[4] = rxbuf[i + 4];
370 		write_buf[5] = rxbuf[i + 5];
371 		write_buf[6] = rxbuf[i + 6];
372 		write_buf[7] = rxbuf[i + 7];
373 
374 		rxbuf[i + 0] = write_buf[7];
375 		rxbuf[i + 1] = write_buf[6];
376 		rxbuf[i + 2] = write_buf[5];
377 		rxbuf[i + 3] = write_buf[4];
378 		rxbuf[i + 4] = write_buf[3];
379 		rxbuf[i + 5] = write_buf[2];
380 		rxbuf[i + 6] = write_buf[1];
381 		rxbuf[i + 7] = write_buf[0];
382 	}
383 
384 	return true;
385 }
386 EXPORT_SYMBOL_GPL(rt5514_spi_burst_read);
387 
388 /**
389  * rt5514_spi_burst_write - Write data to SPI by rt5514 address.
390  * @addr: Start address.
391  * @txbuf: Data Buffer for writng.
392  * @len: Data length, it must be a multiple of 8.
393  *
394  *
395  * Returns true for success.
396  */
397 int rt5514_spi_burst_write(u32 addr, const u8 *txbuf, size_t len)
398 {
399 	u8 spi_cmd = RT5514_SPI_CMD_BURST_WRITE;
400 	u8 *write_buf;
401 	unsigned int i, end, offset = 0;
402 
403 	write_buf = kmalloc(RT5514_SPI_BUF_LEN + 6, GFP_KERNEL);
404 
405 	if (write_buf == NULL)
406 		return -ENOMEM;
407 
408 	while (offset < len) {
409 		if (offset + RT5514_SPI_BUF_LEN <= len)
410 			end = RT5514_SPI_BUF_LEN;
411 		else
412 			end = len % RT5514_SPI_BUF_LEN;
413 
414 		write_buf[0] = spi_cmd;
415 		write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
416 		write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
417 		write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
418 		write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
419 
420 		for (i = 0; i < end; i += 8) {
421 			write_buf[i + 12] = txbuf[offset + i + 0];
422 			write_buf[i + 11] = txbuf[offset + i + 1];
423 			write_buf[i + 10] = txbuf[offset + i + 2];
424 			write_buf[i +  9] = txbuf[offset + i + 3];
425 			write_buf[i +  8] = txbuf[offset + i + 4];
426 			write_buf[i +  7] = txbuf[offset + i + 5];
427 			write_buf[i +  6] = txbuf[offset + i + 6];
428 			write_buf[i +  5] = txbuf[offset + i + 7];
429 		}
430 
431 		write_buf[end + 5] = spi_cmd;
432 
433 		spi_write(rt5514_spi, write_buf, end + 6);
434 
435 		offset += RT5514_SPI_BUF_LEN;
436 	}
437 
438 	kfree(write_buf);
439 
440 	return 0;
441 }
442 EXPORT_SYMBOL_GPL(rt5514_spi_burst_write);
443 
444 static int rt5514_spi_probe(struct spi_device *spi)
445 {
446 	int ret;
447 
448 	rt5514_spi = spi;
449 
450 	ret = devm_snd_soc_register_component(&spi->dev,
451 					      &rt5514_spi_component,
452 					      &rt5514_spi_dai, 1);
453 	if (ret < 0) {
454 		dev_err(&spi->dev, "Failed to register component.\n");
455 		return ret;
456 	}
457 
458 	return 0;
459 }
460 
461 static int __maybe_unused rt5514_suspend(struct device *dev)
462 {
463 	int irq = to_spi_device(dev)->irq;
464 
465 	if (device_may_wakeup(dev))
466 		enable_irq_wake(irq);
467 
468 	return 0;
469 }
470 
471 static int __maybe_unused rt5514_resume(struct device *dev)
472 {
473 	struct rt5514_dsp *rt5514_dsp = dev_get_drvdata(dev);
474 	int irq = to_spi_device(dev)->irq;
475 	u8 buf[8];
476 
477 	if (device_may_wakeup(dev))
478 		disable_irq_wake(irq);
479 
480 	if (rt5514_dsp) {
481 		if (rt5514_dsp->substream) {
482 			rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf,
483 				sizeof(buf));
484 			if (buf[0] & RT5514_IRQ_STATUS_BIT)
485 				rt5514_schedule_copy(rt5514_dsp);
486 		}
487 	}
488 
489 	return 0;
490 }
491 
492 static const struct dev_pm_ops rt5514_pm_ops = {
493 	SET_SYSTEM_SLEEP_PM_OPS(rt5514_suspend, rt5514_resume)
494 };
495 
496 static const struct of_device_id rt5514_of_match[] = {
497 	{ .compatible = "realtek,rt5514", },
498 	{},
499 };
500 MODULE_DEVICE_TABLE(of, rt5514_of_match);
501 
502 static struct spi_driver rt5514_spi_driver = {
503 	.driver = {
504 		.name = "rt5514",
505 		.pm = &rt5514_pm_ops,
506 		.of_match_table = of_match_ptr(rt5514_of_match),
507 	},
508 	.probe = rt5514_spi_probe,
509 };
510 module_spi_driver(rt5514_spi_driver);
511 
512 MODULE_DESCRIPTION("RT5514 SPI driver");
513 MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
514 MODULE_LICENSE("GPL v2");
515