xref: /openbmc/linux/sound/soc/codecs/rt5514-spi.c (revision 6cc23ed2)
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/gpio.h>
19 #include <linux/sched.h>
20 #include <linux/uaccess.h>
21 #include <linux/regulator/consumer.h>
22 #include <linux/pm_qos.h>
23 #include <linux/sysfs.h>
24 #include <linux/clk.h>
25 #include <sound/core.h>
26 #include <sound/pcm.h>
27 #include <sound/pcm_params.h>
28 #include <sound/soc.h>
29 #include <sound/soc-dapm.h>
30 #include <sound/initval.h>
31 #include <sound/tlv.h>
32 
33 #include "rt5514-spi.h"
34 
35 #define DRV_NAME "rt5514-spi"
36 
37 static struct spi_device *rt5514_spi;
38 
39 struct rt5514_dsp {
40 	struct device *dev;
41 	struct delayed_work copy_work;
42 	struct mutex dma_lock;
43 	struct snd_pcm_substream *substream;
44 	unsigned int buf_base, buf_limit, buf_rp;
45 	size_t buf_size, get_size, dma_offset;
46 };
47 
48 static const struct snd_pcm_hardware rt5514_spi_pcm_hardware = {
49 	.info			= SNDRV_PCM_INFO_MMAP |
50 				  SNDRV_PCM_INFO_MMAP_VALID |
51 				  SNDRV_PCM_INFO_INTERLEAVED,
52 	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
53 	.period_bytes_min	= PAGE_SIZE,
54 	.period_bytes_max	= 0x20000 / 8,
55 	.periods_min		= 8,
56 	.periods_max		= 8,
57 	.channels_min		= 1,
58 	.channels_max		= 1,
59 	.buffer_bytes_max	= 0x20000,
60 };
61 
62 static struct snd_soc_dai_driver rt5514_spi_dai = {
63 	.name = "rt5514-dsp-cpu-dai",
64 	.id = 0,
65 	.capture = {
66 		.stream_name = "DSP Capture",
67 		.channels_min = 1,
68 		.channels_max = 1,
69 		.rates = SNDRV_PCM_RATE_16000,
70 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
71 	},
72 };
73 
74 static void rt5514_spi_copy_work(struct work_struct *work)
75 {
76 	struct rt5514_dsp *rt5514_dsp =
77 		container_of(work, struct rt5514_dsp, copy_work.work);
78 	struct snd_pcm_runtime *runtime;
79 	size_t period_bytes, truncated_bytes = 0;
80 	unsigned int cur_wp, remain_data;
81 	u8 buf[8];
82 
83 	mutex_lock(&rt5514_dsp->dma_lock);
84 	if (!rt5514_dsp->substream) {
85 		dev_err(rt5514_dsp->dev, "No pcm substream\n");
86 		goto done;
87 	}
88 
89 	runtime = rt5514_dsp->substream->runtime;
90 	period_bytes = snd_pcm_lib_period_bytes(rt5514_dsp->substream);
91 	if (!period_bytes) {
92 		schedule_delayed_work(&rt5514_dsp->copy_work, 5);
93 		goto done;
94 	}
95 
96 	if (rt5514_dsp->buf_size % period_bytes)
97 		rt5514_dsp->buf_size = (rt5514_dsp->buf_size / period_bytes) *
98 			period_bytes;
99 
100 	if (rt5514_dsp->get_size >= rt5514_dsp->buf_size) {
101 		rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
102 			sizeof(buf));
103 		cur_wp = buf[0] | buf[1] << 8 | buf[2] << 16 |
104 					buf[3] << 24;
105 
106 		if (cur_wp >= rt5514_dsp->buf_rp)
107 			remain_data = (cur_wp - rt5514_dsp->buf_rp);
108 		else
109 			remain_data =
110 				(rt5514_dsp->buf_limit - rt5514_dsp->buf_rp) +
111 				(cur_wp - rt5514_dsp->buf_base);
112 
113 		if (remain_data < period_bytes) {
114 			schedule_delayed_work(&rt5514_dsp->copy_work, 5);
115 			goto done;
116 		}
117 	}
118 
119 	if (rt5514_dsp->buf_rp + period_bytes <= rt5514_dsp->buf_limit) {
120 		rt5514_spi_burst_read(rt5514_dsp->buf_rp,
121 			runtime->dma_area + rt5514_dsp->dma_offset,
122 			period_bytes);
123 
124 		if (rt5514_dsp->buf_rp + period_bytes == rt5514_dsp->buf_limit)
125 			rt5514_dsp->buf_rp = rt5514_dsp->buf_base;
126 		else
127 			rt5514_dsp->buf_rp += period_bytes;
128 	} else {
129 		truncated_bytes = rt5514_dsp->buf_limit - rt5514_dsp->buf_rp;
130 		rt5514_spi_burst_read(rt5514_dsp->buf_rp,
131 			runtime->dma_area + rt5514_dsp->dma_offset,
132 			truncated_bytes);
133 
134 		rt5514_spi_burst_read(rt5514_dsp->buf_base,
135 			runtime->dma_area + rt5514_dsp->dma_offset +
136 			truncated_bytes, period_bytes - truncated_bytes);
137 
138 		rt5514_dsp->buf_rp = rt5514_dsp->buf_base + period_bytes -
139 			truncated_bytes;
140 	}
141 
142 	rt5514_dsp->get_size += period_bytes;
143 	rt5514_dsp->dma_offset += period_bytes;
144 	if (rt5514_dsp->dma_offset >= runtime->dma_bytes)
145 		rt5514_dsp->dma_offset = 0;
146 
147 	snd_pcm_period_elapsed(rt5514_dsp->substream);
148 
149 	schedule_delayed_work(&rt5514_dsp->copy_work, 5);
150 
151 done:
152 	mutex_unlock(&rt5514_dsp->dma_lock);
153 }
154 
155 static void rt5514_schedule_copy(struct rt5514_dsp *rt5514_dsp)
156 {
157 	u8 buf[8];
158 
159 	if (!rt5514_dsp->substream)
160 		return;
161 
162 	rt5514_dsp->get_size = 0;
163 
164 	/**
165 	 * The address area x1800XXXX is the register address, and it cannot
166 	 * support spi burst read perfectly. So we use the spi burst read
167 	 * individually to make sure the data correctly.
168 	 */
169 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_BASE, (u8 *)&buf,
170 		sizeof(buf));
171 	rt5514_dsp->buf_base = buf[0] | buf[1] << 8 | buf[2] << 16 |
172 				buf[3] << 24;
173 
174 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_LIMIT, (u8 *)&buf,
175 		sizeof(buf));
176 	rt5514_dsp->buf_limit = buf[0] | buf[1] << 8 | buf[2] << 16 |
177 				buf[3] << 24;
178 
179 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
180 		sizeof(buf));
181 	rt5514_dsp->buf_rp = buf[0] | buf[1] << 8 | buf[2] << 16 |
182 				buf[3] << 24;
183 
184 	if (rt5514_dsp->buf_rp % 8)
185 		rt5514_dsp->buf_rp = (rt5514_dsp->buf_rp / 8) * 8;
186 
187 	rt5514_dsp->buf_size = rt5514_dsp->buf_limit - rt5514_dsp->buf_base;
188 
189 	if (rt5514_dsp->buf_base && rt5514_dsp->buf_limit &&
190 		rt5514_dsp->buf_rp && rt5514_dsp->buf_size)
191 		schedule_delayed_work(&rt5514_dsp->copy_work, 0);
192 }
193 
194 static irqreturn_t rt5514_spi_irq(int irq, void *data)
195 {
196 	struct rt5514_dsp *rt5514_dsp = data;
197 
198 	rt5514_schedule_copy(rt5514_dsp);
199 
200 	return IRQ_HANDLED;
201 }
202 
203 /* PCM for streaming audio from the DSP buffer */
204 static int rt5514_spi_pcm_open(struct snd_soc_component *component,
205 			       struct snd_pcm_substream *substream)
206 {
207 	snd_soc_set_runtime_hwparams(substream, &rt5514_spi_pcm_hardware);
208 
209 	return 0;
210 }
211 
212 static int rt5514_spi_hw_params(struct snd_soc_component *component,
213 				struct snd_pcm_substream *substream,
214 				struct snd_pcm_hw_params *hw_params)
215 {
216 	struct rt5514_dsp *rt5514_dsp =
217 		snd_soc_component_get_drvdata(component);
218 	int ret;
219 	u8 buf[8];
220 
221 	mutex_lock(&rt5514_dsp->dma_lock);
222 	ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
223 			params_buffer_bytes(hw_params));
224 	rt5514_dsp->substream = substream;
225 	rt5514_dsp->dma_offset = 0;
226 
227 	/* Read IRQ status and schedule copy accordingly. */
228 	rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf, sizeof(buf));
229 	if (buf[0] & RT5514_IRQ_STATUS_BIT)
230 		rt5514_schedule_copy(rt5514_dsp);
231 
232 	mutex_unlock(&rt5514_dsp->dma_lock);
233 
234 	return ret;
235 }
236 
237 static int rt5514_spi_hw_free(struct snd_soc_component *component,
238 			      struct snd_pcm_substream *substream)
239 {
240 	struct rt5514_dsp *rt5514_dsp =
241 		snd_soc_component_get_drvdata(component);
242 
243 	mutex_lock(&rt5514_dsp->dma_lock);
244 	rt5514_dsp->substream = NULL;
245 	mutex_unlock(&rt5514_dsp->dma_lock);
246 
247 	cancel_delayed_work_sync(&rt5514_dsp->copy_work);
248 
249 	return snd_pcm_lib_free_vmalloc_buffer(substream);
250 }
251 
252 static snd_pcm_uframes_t rt5514_spi_pcm_pointer(
253 		struct snd_soc_component *component,
254 		struct snd_pcm_substream *substream)
255 {
256 	struct snd_pcm_runtime *runtime = substream->runtime;
257 	struct rt5514_dsp *rt5514_dsp =
258 		snd_soc_component_get_drvdata(component);
259 
260 	return bytes_to_frames(runtime, rt5514_dsp->dma_offset);
261 }
262 
263 static struct page *rt5514_spi_pcm_page(struct snd_soc_component *component,
264 					struct snd_pcm_substream *substream,
265 					unsigned long offset)
266 {
267 	return snd_pcm_lib_get_vmalloc_page(substream, offset);
268 }
269 
270 static int rt5514_spi_pcm_probe(struct snd_soc_component *component)
271 {
272 	struct rt5514_dsp *rt5514_dsp;
273 	int ret;
274 
275 	rt5514_dsp = devm_kzalloc(component->dev, sizeof(*rt5514_dsp),
276 			GFP_KERNEL);
277 	if (!rt5514_dsp)
278 		return -ENOMEM;
279 
280 	rt5514_dsp->dev = &rt5514_spi->dev;
281 	mutex_init(&rt5514_dsp->dma_lock);
282 	INIT_DELAYED_WORK(&rt5514_dsp->copy_work, rt5514_spi_copy_work);
283 	snd_soc_component_set_drvdata(component, rt5514_dsp);
284 
285 	if (rt5514_spi->irq) {
286 		ret = devm_request_threaded_irq(&rt5514_spi->dev,
287 			rt5514_spi->irq, NULL, rt5514_spi_irq,
288 			IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rt5514-spi",
289 			rt5514_dsp);
290 		if (ret)
291 			dev_err(&rt5514_spi->dev,
292 				"%s Failed to reguest IRQ: %d\n", __func__,
293 				ret);
294 		else
295 			device_init_wakeup(rt5514_dsp->dev, true);
296 	}
297 
298 	return 0;
299 }
300 
301 static const struct snd_soc_component_driver rt5514_spi_component = {
302 	.name		= DRV_NAME,
303 	.probe		= rt5514_spi_pcm_probe,
304 	.open		= rt5514_spi_pcm_open,
305 	.hw_params	= rt5514_spi_hw_params,
306 	.hw_free	= rt5514_spi_hw_free,
307 	.pointer	= rt5514_spi_pcm_pointer,
308 	.page		= rt5514_spi_pcm_page,
309 };
310 
311 /**
312  * rt5514_spi_burst_read - Read data from SPI by rt5514 address.
313  * @addr: Start address.
314  * @rxbuf: Data Buffer for reading.
315  * @len: Data length, it must be a multiple of 8.
316  *
317  *
318  * Returns true for success.
319  */
320 int rt5514_spi_burst_read(unsigned int addr, u8 *rxbuf, size_t len)
321 {
322 	u8 spi_cmd = RT5514_SPI_CMD_BURST_READ;
323 	int status;
324 	u8 write_buf[8];
325 	unsigned int i, end, offset = 0;
326 
327 	struct spi_message message;
328 	struct spi_transfer x[3];
329 
330 	while (offset < len) {
331 		if (offset + RT5514_SPI_BUF_LEN <= len)
332 			end = RT5514_SPI_BUF_LEN;
333 		else
334 			end = len % RT5514_SPI_BUF_LEN;
335 
336 		write_buf[0] = spi_cmd;
337 		write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
338 		write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
339 		write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
340 		write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
341 
342 		spi_message_init(&message);
343 		memset(x, 0, sizeof(x));
344 
345 		x[0].len = 5;
346 		x[0].tx_buf = write_buf;
347 		spi_message_add_tail(&x[0], &message);
348 
349 		x[1].len = 4;
350 		x[1].tx_buf = write_buf;
351 		spi_message_add_tail(&x[1], &message);
352 
353 		x[2].len = end;
354 		x[2].rx_buf = rxbuf + offset;
355 		spi_message_add_tail(&x[2], &message);
356 
357 		status = spi_sync(rt5514_spi, &message);
358 
359 		if (status)
360 			return false;
361 
362 		offset += RT5514_SPI_BUF_LEN;
363 	}
364 
365 	for (i = 0; i < len; i += 8) {
366 		write_buf[0] = rxbuf[i + 0];
367 		write_buf[1] = rxbuf[i + 1];
368 		write_buf[2] = rxbuf[i + 2];
369 		write_buf[3] = rxbuf[i + 3];
370 		write_buf[4] = rxbuf[i + 4];
371 		write_buf[5] = rxbuf[i + 5];
372 		write_buf[6] = rxbuf[i + 6];
373 		write_buf[7] = rxbuf[i + 7];
374 
375 		rxbuf[i + 0] = write_buf[7];
376 		rxbuf[i + 1] = write_buf[6];
377 		rxbuf[i + 2] = write_buf[5];
378 		rxbuf[i + 3] = write_buf[4];
379 		rxbuf[i + 4] = write_buf[3];
380 		rxbuf[i + 5] = write_buf[2];
381 		rxbuf[i + 6] = write_buf[1];
382 		rxbuf[i + 7] = write_buf[0];
383 	}
384 
385 	return true;
386 }
387 EXPORT_SYMBOL_GPL(rt5514_spi_burst_read);
388 
389 /**
390  * rt5514_spi_burst_write - Write data to SPI by rt5514 address.
391  * @addr: Start address.
392  * @txbuf: Data Buffer for writng.
393  * @len: Data length, it must be a multiple of 8.
394  *
395  *
396  * Returns true for success.
397  */
398 int rt5514_spi_burst_write(u32 addr, const u8 *txbuf, size_t len)
399 {
400 	u8 spi_cmd = RT5514_SPI_CMD_BURST_WRITE;
401 	u8 *write_buf;
402 	unsigned int i, end, offset = 0;
403 
404 	write_buf = kmalloc(RT5514_SPI_BUF_LEN + 6, GFP_KERNEL);
405 
406 	if (write_buf == NULL)
407 		return -ENOMEM;
408 
409 	while (offset < len) {
410 		if (offset + RT5514_SPI_BUF_LEN <= len)
411 			end = RT5514_SPI_BUF_LEN;
412 		else
413 			end = len % RT5514_SPI_BUF_LEN;
414 
415 		write_buf[0] = spi_cmd;
416 		write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
417 		write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
418 		write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
419 		write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
420 
421 		for (i = 0; i < end; i += 8) {
422 			write_buf[i + 12] = txbuf[offset + i + 0];
423 			write_buf[i + 11] = txbuf[offset + i + 1];
424 			write_buf[i + 10] = txbuf[offset + i + 2];
425 			write_buf[i +  9] = txbuf[offset + i + 3];
426 			write_buf[i +  8] = txbuf[offset + i + 4];
427 			write_buf[i +  7] = txbuf[offset + i + 5];
428 			write_buf[i +  6] = txbuf[offset + i + 6];
429 			write_buf[i +  5] = txbuf[offset + i + 7];
430 		}
431 
432 		write_buf[end + 5] = spi_cmd;
433 
434 		spi_write(rt5514_spi, write_buf, end + 6);
435 
436 		offset += RT5514_SPI_BUF_LEN;
437 	}
438 
439 	kfree(write_buf);
440 
441 	return 0;
442 }
443 EXPORT_SYMBOL_GPL(rt5514_spi_burst_write);
444 
445 static int rt5514_spi_probe(struct spi_device *spi)
446 {
447 	int ret;
448 
449 	rt5514_spi = spi;
450 
451 	ret = devm_snd_soc_register_component(&spi->dev,
452 					      &rt5514_spi_component,
453 					      &rt5514_spi_dai, 1);
454 	if (ret < 0) {
455 		dev_err(&spi->dev, "Failed to register component.\n");
456 		return ret;
457 	}
458 
459 	return 0;
460 }
461 
462 static int __maybe_unused rt5514_suspend(struct device *dev)
463 {
464 	int irq = to_spi_device(dev)->irq;
465 
466 	if (device_may_wakeup(dev))
467 		enable_irq_wake(irq);
468 
469 	return 0;
470 }
471 
472 static int __maybe_unused rt5514_resume(struct device *dev)
473 {
474 	struct rt5514_dsp *rt5514_dsp = dev_get_drvdata(dev);
475 	int irq = to_spi_device(dev)->irq;
476 	u8 buf[8];
477 
478 	if (device_may_wakeup(dev))
479 		disable_irq_wake(irq);
480 
481 	if (rt5514_dsp) {
482 		if (rt5514_dsp->substream) {
483 			rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf,
484 				sizeof(buf));
485 			if (buf[0] & RT5514_IRQ_STATUS_BIT)
486 				rt5514_schedule_copy(rt5514_dsp);
487 		}
488 	}
489 
490 	return 0;
491 }
492 
493 static const struct dev_pm_ops rt5514_pm_ops = {
494 	SET_SYSTEM_SLEEP_PM_OPS(rt5514_suspend, rt5514_resume)
495 };
496 
497 static const struct of_device_id rt5514_of_match[] = {
498 	{ .compatible = "realtek,rt5514", },
499 	{},
500 };
501 MODULE_DEVICE_TABLE(of, rt5514_of_match);
502 
503 static struct spi_driver rt5514_spi_driver = {
504 	.driver = {
505 		.name = "rt5514",
506 		.pm = &rt5514_pm_ops,
507 		.of_match_table = of_match_ptr(rt5514_of_match),
508 	},
509 	.probe = rt5514_spi_probe,
510 };
511 module_spi_driver(rt5514_spi_driver);
512 
513 MODULE_DESCRIPTION("RT5514 SPI driver");
514 MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
515 MODULE_LICENSE("GPL v2");
516