xref: /openbmc/linux/sound/soc/codecs/rt5514-spi.c (revision fcbd8037)
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_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_pcm_substream *substream,
212 			       struct snd_pcm_hw_params *hw_params)
213 {
214 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
215 	struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME);
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_pcm_substream *substream)
238 {
239 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
240 	struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME);
241 	struct rt5514_dsp *rt5514_dsp =
242 		snd_soc_component_get_drvdata(component);
243 
244 	mutex_lock(&rt5514_dsp->dma_lock);
245 	rt5514_dsp->substream = NULL;
246 	mutex_unlock(&rt5514_dsp->dma_lock);
247 
248 	cancel_delayed_work_sync(&rt5514_dsp->copy_work);
249 
250 	return snd_pcm_lib_free_vmalloc_buffer(substream);
251 }
252 
253 static snd_pcm_uframes_t rt5514_spi_pcm_pointer(
254 		struct snd_pcm_substream *substream)
255 {
256 	struct snd_pcm_runtime *runtime = substream->runtime;
257 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
258 	struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME);
259 	struct rt5514_dsp *rt5514_dsp =
260 		snd_soc_component_get_drvdata(component);
261 
262 	return bytes_to_frames(runtime, rt5514_dsp->dma_offset);
263 }
264 
265 static const struct snd_pcm_ops rt5514_spi_pcm_ops = {
266 	.open		= rt5514_spi_pcm_open,
267 	.hw_params	= rt5514_spi_hw_params,
268 	.hw_free	= rt5514_spi_hw_free,
269 	.pointer	= rt5514_spi_pcm_pointer,
270 	.page		= snd_pcm_lib_get_vmalloc_page,
271 };
272 
273 static int rt5514_spi_pcm_probe(struct snd_soc_component *component)
274 {
275 	struct rt5514_dsp *rt5514_dsp;
276 	int ret;
277 
278 	rt5514_dsp = devm_kzalloc(component->dev, sizeof(*rt5514_dsp),
279 			GFP_KERNEL);
280 	if (!rt5514_dsp)
281 		return -ENOMEM;
282 
283 	rt5514_dsp->dev = &rt5514_spi->dev;
284 	mutex_init(&rt5514_dsp->dma_lock);
285 	INIT_DELAYED_WORK(&rt5514_dsp->copy_work, rt5514_spi_copy_work);
286 	snd_soc_component_set_drvdata(component, rt5514_dsp);
287 
288 	if (rt5514_spi->irq) {
289 		ret = devm_request_threaded_irq(&rt5514_spi->dev,
290 			rt5514_spi->irq, NULL, rt5514_spi_irq,
291 			IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rt5514-spi",
292 			rt5514_dsp);
293 		if (ret)
294 			dev_err(&rt5514_spi->dev,
295 				"%s Failed to reguest IRQ: %d\n", __func__,
296 				ret);
297 		else
298 			device_init_wakeup(rt5514_dsp->dev, true);
299 	}
300 
301 	return 0;
302 }
303 
304 static const struct snd_soc_component_driver rt5514_spi_component = {
305 	.name  = DRV_NAME,
306 	.probe = rt5514_spi_pcm_probe,
307 	.ops = &rt5514_spi_pcm_ops,
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