xref: /openbmc/linux/sound/soc/codecs/rt5514-spi.c (revision a9a08845)
1 /*
2  * rt5514-spi.c  --  RT5514 SPI driver
3  *
4  * Copyright 2015 Realtek Semiconductor Corp.
5  * Author: Oder Chiou <oder_chiou@realtek.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 
12 #include <linux/module.h>
13 #include <linux/input.h>
14 #include <linux/spi/spi.h>
15 #include <linux/device.h>
16 #include <linux/init.h>
17 #include <linux/delay.h>
18 #include <linux/interrupt.h>
19 #include <linux/irq.h>
20 #include <linux/slab.h>
21 #include <linux/gpio.h>
22 #include <linux/sched.h>
23 #include <linux/uaccess.h>
24 #include <linux/regulator/consumer.h>
25 #include <linux/pm_qos.h>
26 #include <linux/sysfs.h>
27 #include <linux/clk.h>
28 #include <sound/core.h>
29 #include <sound/pcm.h>
30 #include <sound/pcm_params.h>
31 #include <sound/soc.h>
32 #include <sound/soc-dapm.h>
33 #include <sound/initval.h>
34 #include <sound/tlv.h>
35 
36 #include "rt5514-spi.h"
37 
38 static struct spi_device *rt5514_spi;
39 
40 struct rt5514_dsp {
41 	struct device *dev;
42 	struct delayed_work copy_work;
43 	struct mutex dma_lock;
44 	struct snd_pcm_substream *substream;
45 	unsigned int buf_base, buf_limit, buf_rp;
46 	size_t buf_size, get_size, dma_offset;
47 };
48 
49 static const struct snd_pcm_hardware rt5514_spi_pcm_hardware = {
50 	.info			= SNDRV_PCM_INFO_MMAP |
51 				  SNDRV_PCM_INFO_MMAP_VALID |
52 				  SNDRV_PCM_INFO_INTERLEAVED,
53 	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
54 	.period_bytes_min	= PAGE_SIZE,
55 	.period_bytes_max	= 0x20000 / 8,
56 	.periods_min		= 8,
57 	.periods_max		= 8,
58 	.channels_min		= 1,
59 	.channels_max		= 1,
60 	.buffer_bytes_max	= 0x20000,
61 };
62 
63 static struct snd_soc_dai_driver rt5514_spi_dai = {
64 	.name = "rt5514-dsp-cpu-dai",
65 	.id = 0,
66 	.capture = {
67 		.stream_name = "DSP Capture",
68 		.channels_min = 1,
69 		.channels_max = 1,
70 		.rates = SNDRV_PCM_RATE_16000,
71 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
72 	},
73 };
74 
75 static void rt5514_spi_copy_work(struct work_struct *work)
76 {
77 	struct rt5514_dsp *rt5514_dsp =
78 		container_of(work, struct rt5514_dsp, copy_work.work);
79 	struct snd_pcm_runtime *runtime;
80 	size_t period_bytes, truncated_bytes = 0;
81 	unsigned int cur_wp, remain_data;
82 	u8 buf[8];
83 
84 	mutex_lock(&rt5514_dsp->dma_lock);
85 	if (!rt5514_dsp->substream) {
86 		dev_err(rt5514_dsp->dev, "No pcm substream\n");
87 		goto done;
88 	}
89 
90 	runtime = rt5514_dsp->substream->runtime;
91 	period_bytes = snd_pcm_lib_period_bytes(rt5514_dsp->substream);
92 
93 	if (rt5514_dsp->get_size >= rt5514_dsp->buf_size) {
94 		rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
95 			sizeof(buf));
96 		cur_wp = buf[0] | buf[1] << 8 | buf[2] << 16 |
97 					buf[3] << 24;
98 
99 		if (cur_wp >= rt5514_dsp->buf_rp)
100 			remain_data = (cur_wp - rt5514_dsp->buf_rp);
101 		else
102 			remain_data =
103 				(rt5514_dsp->buf_limit - rt5514_dsp->buf_rp) +
104 				(cur_wp - rt5514_dsp->buf_base);
105 
106 		if (remain_data < period_bytes) {
107 			schedule_delayed_work(&rt5514_dsp->copy_work, 5);
108 			goto done;
109 		}
110 	}
111 
112 	if (rt5514_dsp->buf_rp + period_bytes <= rt5514_dsp->buf_limit) {
113 		rt5514_spi_burst_read(rt5514_dsp->buf_rp,
114 			runtime->dma_area + rt5514_dsp->dma_offset,
115 			period_bytes);
116 
117 		if (rt5514_dsp->buf_rp + period_bytes == rt5514_dsp->buf_limit)
118 			rt5514_dsp->buf_rp = rt5514_dsp->buf_base;
119 		else
120 			rt5514_dsp->buf_rp += period_bytes;
121 	} else {
122 		truncated_bytes = rt5514_dsp->buf_limit - rt5514_dsp->buf_rp;
123 		rt5514_spi_burst_read(rt5514_dsp->buf_rp,
124 			runtime->dma_area + rt5514_dsp->dma_offset,
125 			truncated_bytes);
126 
127 		rt5514_spi_burst_read(rt5514_dsp->buf_base,
128 			runtime->dma_area + rt5514_dsp->dma_offset +
129 			truncated_bytes, period_bytes - truncated_bytes);
130 
131 		rt5514_dsp->buf_rp = rt5514_dsp->buf_base + period_bytes -
132 			truncated_bytes;
133 	}
134 
135 	rt5514_dsp->get_size += period_bytes;
136 	rt5514_dsp->dma_offset += period_bytes;
137 	if (rt5514_dsp->dma_offset >= runtime->dma_bytes)
138 		rt5514_dsp->dma_offset = 0;
139 
140 	snd_pcm_period_elapsed(rt5514_dsp->substream);
141 
142 	schedule_delayed_work(&rt5514_dsp->copy_work, 5);
143 
144 done:
145 	mutex_unlock(&rt5514_dsp->dma_lock);
146 }
147 
148 static void rt5514_schedule_copy(struct rt5514_dsp *rt5514_dsp)
149 {
150 	size_t period_bytes;
151 	u8 buf[8];
152 
153 	if (!rt5514_dsp->substream)
154 		return;
155 
156 	period_bytes = snd_pcm_lib_period_bytes(rt5514_dsp->substream);
157 	rt5514_dsp->get_size = 0;
158 
159 	/**
160 	 * The address area x1800XXXX is the register address, and it cannot
161 	 * support spi burst read perfectly. So we use the spi burst read
162 	 * individually to make sure the data correctly.
163 	 */
164 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_BASE, (u8 *)&buf,
165 		sizeof(buf));
166 	rt5514_dsp->buf_base = buf[0] | buf[1] << 8 | buf[2] << 16 |
167 				buf[3] << 24;
168 
169 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_LIMIT, (u8 *)&buf,
170 		sizeof(buf));
171 	rt5514_dsp->buf_limit = buf[0] | buf[1] << 8 | buf[2] << 16 |
172 				buf[3] << 24;
173 
174 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
175 		sizeof(buf));
176 	rt5514_dsp->buf_rp = buf[0] | buf[1] << 8 | buf[2] << 16 |
177 				buf[3] << 24;
178 
179 	if (rt5514_dsp->buf_rp % 8)
180 		rt5514_dsp->buf_rp = (rt5514_dsp->buf_rp / 8) * 8;
181 
182 	rt5514_dsp->buf_size = rt5514_dsp->buf_limit - rt5514_dsp->buf_base;
183 
184 	if (rt5514_dsp->buf_size % period_bytes)
185 		rt5514_dsp->buf_size = (rt5514_dsp->buf_size / period_bytes) *
186 			period_bytes;
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_pcm_substream *substream)
204 {
205 	snd_soc_set_runtime_hwparams(substream, &rt5514_spi_pcm_hardware);
206 
207 	return 0;
208 }
209 
210 static int rt5514_spi_hw_params(struct snd_pcm_substream *substream,
211 			       struct snd_pcm_hw_params *hw_params)
212 {
213 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
214 	struct rt5514_dsp *rt5514_dsp =
215 			snd_soc_platform_get_drvdata(rtd->platform);
216 	int ret;
217 	u8 buf[8];
218 
219 	mutex_lock(&rt5514_dsp->dma_lock);
220 	ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
221 			params_buffer_bytes(hw_params));
222 	rt5514_dsp->substream = substream;
223 	rt5514_dsp->dma_offset = 0;
224 
225 	/* Read IRQ status and schedule copy accordingly. */
226 	rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf, sizeof(buf));
227 	if (buf[0] & RT5514_IRQ_STATUS_BIT)
228 		rt5514_schedule_copy(rt5514_dsp);
229 
230 	mutex_unlock(&rt5514_dsp->dma_lock);
231 
232 	return ret;
233 }
234 
235 static int rt5514_spi_hw_free(struct snd_pcm_substream *substream)
236 {
237 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
238 	struct rt5514_dsp *rt5514_dsp =
239 			snd_soc_platform_get_drvdata(rtd->platform);
240 
241 	mutex_lock(&rt5514_dsp->dma_lock);
242 	rt5514_dsp->substream = NULL;
243 	mutex_unlock(&rt5514_dsp->dma_lock);
244 
245 	cancel_delayed_work_sync(&rt5514_dsp->copy_work);
246 
247 	return snd_pcm_lib_free_vmalloc_buffer(substream);
248 }
249 
250 static snd_pcm_uframes_t rt5514_spi_pcm_pointer(
251 		struct snd_pcm_substream *substream)
252 {
253 	struct snd_pcm_runtime *runtime = substream->runtime;
254 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
255 	struct rt5514_dsp *rt5514_dsp =
256 		snd_soc_platform_get_drvdata(rtd->platform);
257 
258 	return bytes_to_frames(runtime, rt5514_dsp->dma_offset);
259 }
260 
261 static const struct snd_pcm_ops rt5514_spi_pcm_ops = {
262 	.open		= rt5514_spi_pcm_open,
263 	.hw_params	= rt5514_spi_hw_params,
264 	.hw_free	= rt5514_spi_hw_free,
265 	.pointer	= rt5514_spi_pcm_pointer,
266 	.mmap		= snd_pcm_lib_mmap_vmalloc,
267 	.page		= snd_pcm_lib_get_vmalloc_page,
268 };
269 
270 static int rt5514_spi_pcm_probe(struct snd_soc_platform *platform)
271 {
272 	struct rt5514_dsp *rt5514_dsp;
273 	int ret;
274 
275 	rt5514_dsp = devm_kzalloc(platform->dev, sizeof(*rt5514_dsp),
276 			GFP_KERNEL);
277 
278 	rt5514_dsp->dev = &rt5514_spi->dev;
279 	mutex_init(&rt5514_dsp->dma_lock);
280 	INIT_DELAYED_WORK(&rt5514_dsp->copy_work, rt5514_spi_copy_work);
281 	snd_soc_platform_set_drvdata(platform, rt5514_dsp);
282 
283 	if (rt5514_spi->irq) {
284 		ret = devm_request_threaded_irq(&rt5514_spi->dev,
285 			rt5514_spi->irq, NULL, rt5514_spi_irq,
286 			IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rt5514-spi",
287 			rt5514_dsp);
288 		if (ret)
289 			dev_err(&rt5514_spi->dev,
290 				"%s Failed to reguest IRQ: %d\n", __func__,
291 				ret);
292 		else
293 			device_init_wakeup(rt5514_dsp->dev, true);
294 	}
295 
296 	return 0;
297 }
298 
299 static const struct snd_soc_platform_driver rt5514_spi_platform = {
300 	.probe = rt5514_spi_pcm_probe,
301 	.ops = &rt5514_spi_pcm_ops,
302 };
303 
304 static const struct snd_soc_component_driver rt5514_spi_dai_component = {
305 	.name		= "rt5514-spi-dai",
306 };
307 
308 /**
309  * rt5514_spi_burst_read - Read data from SPI by rt5514 address.
310  * @addr: Start address.
311  * @rxbuf: Data Buffer for reading.
312  * @len: Data length, it must be a multiple of 8.
313  *
314  *
315  * Returns true for success.
316  */
317 int rt5514_spi_burst_read(unsigned int addr, u8 *rxbuf, size_t len)
318 {
319 	u8 spi_cmd = RT5514_SPI_CMD_BURST_READ;
320 	int status;
321 	u8 write_buf[8];
322 	unsigned int i, end, offset = 0;
323 
324 	struct spi_message message;
325 	struct spi_transfer x[3];
326 
327 	while (offset < len) {
328 		if (offset + RT5514_SPI_BUF_LEN <= len)
329 			end = RT5514_SPI_BUF_LEN;
330 		else
331 			end = len % RT5514_SPI_BUF_LEN;
332 
333 		write_buf[0] = spi_cmd;
334 		write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
335 		write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
336 		write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
337 		write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
338 
339 		spi_message_init(&message);
340 		memset(x, 0, sizeof(x));
341 
342 		x[0].len = 5;
343 		x[0].tx_buf = write_buf;
344 		spi_message_add_tail(&x[0], &message);
345 
346 		x[1].len = 4;
347 		x[1].tx_buf = write_buf;
348 		spi_message_add_tail(&x[1], &message);
349 
350 		x[2].len = end;
351 		x[2].rx_buf = rxbuf + offset;
352 		spi_message_add_tail(&x[2], &message);
353 
354 		status = spi_sync(rt5514_spi, &message);
355 
356 		if (status)
357 			return false;
358 
359 		offset += RT5514_SPI_BUF_LEN;
360 	}
361 
362 	for (i = 0; i < len; i += 8) {
363 		write_buf[0] = rxbuf[i + 0];
364 		write_buf[1] = rxbuf[i + 1];
365 		write_buf[2] = rxbuf[i + 2];
366 		write_buf[3] = rxbuf[i + 3];
367 		write_buf[4] = rxbuf[i + 4];
368 		write_buf[5] = rxbuf[i + 5];
369 		write_buf[6] = rxbuf[i + 6];
370 		write_buf[7] = rxbuf[i + 7];
371 
372 		rxbuf[i + 0] = write_buf[7];
373 		rxbuf[i + 1] = write_buf[6];
374 		rxbuf[i + 2] = write_buf[5];
375 		rxbuf[i + 3] = write_buf[4];
376 		rxbuf[i + 4] = write_buf[3];
377 		rxbuf[i + 5] = write_buf[2];
378 		rxbuf[i + 6] = write_buf[1];
379 		rxbuf[i + 7] = write_buf[0];
380 	}
381 
382 	return true;
383 }
384 EXPORT_SYMBOL_GPL(rt5514_spi_burst_read);
385 
386 /**
387  * rt5514_spi_burst_write - Write data to SPI by rt5514 address.
388  * @addr: Start address.
389  * @txbuf: Data Buffer for writng.
390  * @len: Data length, it must be a multiple of 8.
391  *
392  *
393  * Returns true for success.
394  */
395 int rt5514_spi_burst_write(u32 addr, const u8 *txbuf, size_t len)
396 {
397 	u8 spi_cmd = RT5514_SPI_CMD_BURST_WRITE;
398 	u8 *write_buf;
399 	unsigned int i, end, offset = 0;
400 
401 	write_buf = kmalloc(RT5514_SPI_BUF_LEN + 6, GFP_KERNEL);
402 
403 	if (write_buf == NULL)
404 		return -ENOMEM;
405 
406 	while (offset < len) {
407 		if (offset + RT5514_SPI_BUF_LEN <= len)
408 			end = RT5514_SPI_BUF_LEN;
409 		else
410 			end = len % RT5514_SPI_BUF_LEN;
411 
412 		write_buf[0] = spi_cmd;
413 		write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
414 		write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
415 		write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
416 		write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
417 
418 		for (i = 0; i < end; i += 8) {
419 			write_buf[i + 12] = txbuf[offset + i + 0];
420 			write_buf[i + 11] = txbuf[offset + i + 1];
421 			write_buf[i + 10] = txbuf[offset + i + 2];
422 			write_buf[i +  9] = txbuf[offset + i + 3];
423 			write_buf[i +  8] = txbuf[offset + i + 4];
424 			write_buf[i +  7] = txbuf[offset + i + 5];
425 			write_buf[i +  6] = txbuf[offset + i + 6];
426 			write_buf[i +  5] = txbuf[offset + i + 7];
427 		}
428 
429 		write_buf[end + 5] = spi_cmd;
430 
431 		spi_write(rt5514_spi, write_buf, end + 6);
432 
433 		offset += RT5514_SPI_BUF_LEN;
434 	}
435 
436 	kfree(write_buf);
437 
438 	return 0;
439 }
440 EXPORT_SYMBOL_GPL(rt5514_spi_burst_write);
441 
442 static int rt5514_spi_probe(struct spi_device *spi)
443 {
444 	int ret;
445 
446 	rt5514_spi = spi;
447 
448 	ret = devm_snd_soc_register_platform(&spi->dev, &rt5514_spi_platform);
449 	if (ret < 0) {
450 		dev_err(&spi->dev, "Failed to register platform.\n");
451 		return ret;
452 	}
453 
454 	ret = devm_snd_soc_register_component(&spi->dev,
455 					      &rt5514_spi_dai_component,
456 					      &rt5514_spi_dai, 1);
457 	if (ret < 0) {
458 		dev_err(&spi->dev, "Failed to register component.\n");
459 		return ret;
460 	}
461 
462 	return 0;
463 }
464 
465 static int __maybe_unused rt5514_suspend(struct device *dev)
466 {
467 	int irq = to_spi_device(dev)->irq;
468 
469 	if (device_may_wakeup(dev))
470 		enable_irq_wake(irq);
471 
472 	return 0;
473 }
474 
475 static int __maybe_unused rt5514_resume(struct device *dev)
476 {
477 	struct snd_soc_platform *platform = snd_soc_lookup_platform(dev);
478 	struct rt5514_dsp *rt5514_dsp =
479 		snd_soc_platform_get_drvdata(platform);
480 	int irq = to_spi_device(dev)->irq;
481 	u8 buf[8];
482 
483 	if (device_may_wakeup(dev))
484 		disable_irq_wake(irq);
485 
486 	if (rt5514_dsp) {
487 		if (rt5514_dsp->substream) {
488 			rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf,
489 				sizeof(buf));
490 			if (buf[0] & RT5514_IRQ_STATUS_BIT)
491 				rt5514_schedule_copy(rt5514_dsp);
492 		}
493 	}
494 
495 	return 0;
496 }
497 
498 static const struct dev_pm_ops rt5514_pm_ops = {
499 	SET_SYSTEM_SLEEP_PM_OPS(rt5514_suspend, rt5514_resume)
500 };
501 
502 static const struct of_device_id rt5514_of_match[] = {
503 	{ .compatible = "realtek,rt5514", },
504 	{},
505 };
506 MODULE_DEVICE_TABLE(of, rt5514_of_match);
507 
508 static struct spi_driver rt5514_spi_driver = {
509 	.driver = {
510 		.name = "rt5514",
511 		.pm = &rt5514_pm_ops,
512 		.of_match_table = of_match_ptr(rt5514_of_match),
513 	},
514 	.probe = rt5514_spi_probe,
515 };
516 module_spi_driver(rt5514_spi_driver);
517 
518 MODULE_DESCRIPTION("RT5514 SPI driver");
519 MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
520 MODULE_LICENSE("GPL v2");
521