xref: /openbmc/linux/sound/soc/codecs/rt5514-spi.c (revision 9be08a27)
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 #define DRV_NAME "rt5514-spi"
39 
40 static struct spi_device *rt5514_spi;
41 
42 struct rt5514_dsp {
43 	struct device *dev;
44 	struct delayed_work copy_work;
45 	struct mutex dma_lock;
46 	struct snd_pcm_substream *substream;
47 	unsigned int buf_base, buf_limit, buf_rp;
48 	size_t buf_size, get_size, dma_offset;
49 };
50 
51 static const struct snd_pcm_hardware rt5514_spi_pcm_hardware = {
52 	.info			= SNDRV_PCM_INFO_MMAP |
53 				  SNDRV_PCM_INFO_MMAP_VALID |
54 				  SNDRV_PCM_INFO_INTERLEAVED,
55 	.formats		= SNDRV_PCM_FMTBIT_S16_LE,
56 	.period_bytes_min	= PAGE_SIZE,
57 	.period_bytes_max	= 0x20000 / 8,
58 	.periods_min		= 8,
59 	.periods_max		= 8,
60 	.channels_min		= 1,
61 	.channels_max		= 1,
62 	.buffer_bytes_max	= 0x20000,
63 };
64 
65 static struct snd_soc_dai_driver rt5514_spi_dai = {
66 	.name = "rt5514-dsp-cpu-dai",
67 	.id = 0,
68 	.capture = {
69 		.stream_name = "DSP Capture",
70 		.channels_min = 1,
71 		.channels_max = 1,
72 		.rates = SNDRV_PCM_RATE_16000,
73 		.formats = SNDRV_PCM_FMTBIT_S16_LE,
74 	},
75 };
76 
77 static void rt5514_spi_copy_work(struct work_struct *work)
78 {
79 	struct rt5514_dsp *rt5514_dsp =
80 		container_of(work, struct rt5514_dsp, copy_work.work);
81 	struct snd_pcm_runtime *runtime;
82 	size_t period_bytes, truncated_bytes = 0;
83 	unsigned int cur_wp, remain_data;
84 	u8 buf[8];
85 
86 	mutex_lock(&rt5514_dsp->dma_lock);
87 	if (!rt5514_dsp->substream) {
88 		dev_err(rt5514_dsp->dev, "No pcm substream\n");
89 		goto done;
90 	}
91 
92 	runtime = rt5514_dsp->substream->runtime;
93 	period_bytes = snd_pcm_lib_period_bytes(rt5514_dsp->substream);
94 
95 	if (rt5514_dsp->get_size >= rt5514_dsp->buf_size) {
96 		rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
97 			sizeof(buf));
98 		cur_wp = buf[0] | buf[1] << 8 | buf[2] << 16 |
99 					buf[3] << 24;
100 
101 		if (cur_wp >= rt5514_dsp->buf_rp)
102 			remain_data = (cur_wp - rt5514_dsp->buf_rp);
103 		else
104 			remain_data =
105 				(rt5514_dsp->buf_limit - rt5514_dsp->buf_rp) +
106 				(cur_wp - rt5514_dsp->buf_base);
107 
108 		if (remain_data < period_bytes) {
109 			schedule_delayed_work(&rt5514_dsp->copy_work, 5);
110 			goto done;
111 		}
112 	}
113 
114 	if (rt5514_dsp->buf_rp + period_bytes <= rt5514_dsp->buf_limit) {
115 		rt5514_spi_burst_read(rt5514_dsp->buf_rp,
116 			runtime->dma_area + rt5514_dsp->dma_offset,
117 			period_bytes);
118 
119 		if (rt5514_dsp->buf_rp + period_bytes == rt5514_dsp->buf_limit)
120 			rt5514_dsp->buf_rp = rt5514_dsp->buf_base;
121 		else
122 			rt5514_dsp->buf_rp += period_bytes;
123 	} else {
124 		truncated_bytes = rt5514_dsp->buf_limit - rt5514_dsp->buf_rp;
125 		rt5514_spi_burst_read(rt5514_dsp->buf_rp,
126 			runtime->dma_area + rt5514_dsp->dma_offset,
127 			truncated_bytes);
128 
129 		rt5514_spi_burst_read(rt5514_dsp->buf_base,
130 			runtime->dma_area + rt5514_dsp->dma_offset +
131 			truncated_bytes, period_bytes - truncated_bytes);
132 
133 		rt5514_dsp->buf_rp = rt5514_dsp->buf_base + period_bytes -
134 			truncated_bytes;
135 	}
136 
137 	rt5514_dsp->get_size += period_bytes;
138 	rt5514_dsp->dma_offset += period_bytes;
139 	if (rt5514_dsp->dma_offset >= runtime->dma_bytes)
140 		rt5514_dsp->dma_offset = 0;
141 
142 	snd_pcm_period_elapsed(rt5514_dsp->substream);
143 
144 	schedule_delayed_work(&rt5514_dsp->copy_work, 5);
145 
146 done:
147 	mutex_unlock(&rt5514_dsp->dma_lock);
148 }
149 
150 static void rt5514_schedule_copy(struct rt5514_dsp *rt5514_dsp)
151 {
152 	size_t period_bytes;
153 	u8 buf[8];
154 
155 	if (!rt5514_dsp->substream)
156 		return;
157 
158 	period_bytes = snd_pcm_lib_period_bytes(rt5514_dsp->substream);
159 	rt5514_dsp->get_size = 0;
160 
161 	/**
162 	 * The address area x1800XXXX is the register address, and it cannot
163 	 * support spi burst read perfectly. So we use the spi burst read
164 	 * individually to make sure the data correctly.
165 	 */
166 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_BASE, (u8 *)&buf,
167 		sizeof(buf));
168 	rt5514_dsp->buf_base = buf[0] | buf[1] << 8 | buf[2] << 16 |
169 				buf[3] << 24;
170 
171 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_LIMIT, (u8 *)&buf,
172 		sizeof(buf));
173 	rt5514_dsp->buf_limit = buf[0] | buf[1] << 8 | buf[2] << 16 |
174 				buf[3] << 24;
175 
176 	rt5514_spi_burst_read(RT5514_BUFFER_VOICE_WP, (u8 *)&buf,
177 		sizeof(buf));
178 	rt5514_dsp->buf_rp = buf[0] | buf[1] << 8 | buf[2] << 16 |
179 				buf[3] << 24;
180 
181 	if (rt5514_dsp->buf_rp % 8)
182 		rt5514_dsp->buf_rp = (rt5514_dsp->buf_rp / 8) * 8;
183 
184 	rt5514_dsp->buf_size = rt5514_dsp->buf_limit - rt5514_dsp->buf_base;
185 
186 	if (rt5514_dsp->buf_size % period_bytes)
187 		rt5514_dsp->buf_size = (rt5514_dsp->buf_size / period_bytes) *
188 			period_bytes;
189 
190 	if (rt5514_dsp->buf_base && rt5514_dsp->buf_limit &&
191 		rt5514_dsp->buf_rp && rt5514_dsp->buf_size)
192 		schedule_delayed_work(&rt5514_dsp->copy_work, 0);
193 }
194 
195 static irqreturn_t rt5514_spi_irq(int irq, void *data)
196 {
197 	struct rt5514_dsp *rt5514_dsp = data;
198 
199 	rt5514_schedule_copy(rt5514_dsp);
200 
201 	return IRQ_HANDLED;
202 }
203 
204 /* PCM for streaming audio from the DSP buffer */
205 static int rt5514_spi_pcm_open(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_pcm_substream *substream,
213 			       struct snd_pcm_hw_params *hw_params)
214 {
215 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
216 	struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME);
217 	struct rt5514_dsp *rt5514_dsp =
218 		snd_soc_component_get_drvdata(component);
219 	int ret;
220 	u8 buf[8];
221 
222 	mutex_lock(&rt5514_dsp->dma_lock);
223 	ret = snd_pcm_lib_alloc_vmalloc_buffer(substream,
224 			params_buffer_bytes(hw_params));
225 	rt5514_dsp->substream = substream;
226 	rt5514_dsp->dma_offset = 0;
227 
228 	/* Read IRQ status and schedule copy accordingly. */
229 	rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf, sizeof(buf));
230 	if (buf[0] & RT5514_IRQ_STATUS_BIT)
231 		rt5514_schedule_copy(rt5514_dsp);
232 
233 	mutex_unlock(&rt5514_dsp->dma_lock);
234 
235 	return ret;
236 }
237 
238 static int rt5514_spi_hw_free(struct snd_pcm_substream *substream)
239 {
240 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
241 	struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME);
242 	struct rt5514_dsp *rt5514_dsp =
243 		snd_soc_component_get_drvdata(component);
244 
245 	mutex_lock(&rt5514_dsp->dma_lock);
246 	rt5514_dsp->substream = NULL;
247 	mutex_unlock(&rt5514_dsp->dma_lock);
248 
249 	cancel_delayed_work_sync(&rt5514_dsp->copy_work);
250 
251 	return snd_pcm_lib_free_vmalloc_buffer(substream);
252 }
253 
254 static snd_pcm_uframes_t rt5514_spi_pcm_pointer(
255 		struct snd_pcm_substream *substream)
256 {
257 	struct snd_pcm_runtime *runtime = substream->runtime;
258 	struct snd_soc_pcm_runtime *rtd = substream->private_data;
259 	struct snd_soc_component *component = snd_soc_rtdcom_lookup(rtd, DRV_NAME);
260 	struct rt5514_dsp *rt5514_dsp =
261 		snd_soc_component_get_drvdata(component);
262 
263 	return bytes_to_frames(runtime, rt5514_dsp->dma_offset);
264 }
265 
266 static const struct snd_pcm_ops rt5514_spi_pcm_ops = {
267 	.open		= rt5514_spi_pcm_open,
268 	.hw_params	= rt5514_spi_hw_params,
269 	.hw_free	= rt5514_spi_hw_free,
270 	.pointer	= rt5514_spi_pcm_pointer,
271 	.page		= snd_pcm_lib_get_vmalloc_page,
272 };
273 
274 static int rt5514_spi_pcm_probe(struct snd_soc_component *component)
275 {
276 	struct rt5514_dsp *rt5514_dsp;
277 	int ret;
278 
279 	rt5514_dsp = devm_kzalloc(component->dev, sizeof(*rt5514_dsp),
280 			GFP_KERNEL);
281 
282 	rt5514_dsp->dev = &rt5514_spi->dev;
283 	mutex_init(&rt5514_dsp->dma_lock);
284 	INIT_DELAYED_WORK(&rt5514_dsp->copy_work, rt5514_spi_copy_work);
285 	snd_soc_component_set_drvdata(component, rt5514_dsp);
286 
287 	if (rt5514_spi->irq) {
288 		ret = devm_request_threaded_irq(&rt5514_spi->dev,
289 			rt5514_spi->irq, NULL, rt5514_spi_irq,
290 			IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rt5514-spi",
291 			rt5514_dsp);
292 		if (ret)
293 			dev_err(&rt5514_spi->dev,
294 				"%s Failed to reguest IRQ: %d\n", __func__,
295 				ret);
296 		else
297 			device_init_wakeup(rt5514_dsp->dev, true);
298 	}
299 
300 	return 0;
301 }
302 
303 static const struct snd_soc_component_driver rt5514_spi_component = {
304 	.name  = DRV_NAME,
305 	.probe = rt5514_spi_pcm_probe,
306 	.ops = &rt5514_spi_pcm_ops,
307 };
308 
309 /**
310  * rt5514_spi_burst_read - Read data from SPI by rt5514 address.
311  * @addr: Start address.
312  * @rxbuf: Data Buffer for reading.
313  * @len: Data length, it must be a multiple of 8.
314  *
315  *
316  * Returns true for success.
317  */
318 int rt5514_spi_burst_read(unsigned int addr, u8 *rxbuf, size_t len)
319 {
320 	u8 spi_cmd = RT5514_SPI_CMD_BURST_READ;
321 	int status;
322 	u8 write_buf[8];
323 	unsigned int i, end, offset = 0;
324 
325 	struct spi_message message;
326 	struct spi_transfer x[3];
327 
328 	while (offset < len) {
329 		if (offset + RT5514_SPI_BUF_LEN <= len)
330 			end = RT5514_SPI_BUF_LEN;
331 		else
332 			end = len % RT5514_SPI_BUF_LEN;
333 
334 		write_buf[0] = spi_cmd;
335 		write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
336 		write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
337 		write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
338 		write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
339 
340 		spi_message_init(&message);
341 		memset(x, 0, sizeof(x));
342 
343 		x[0].len = 5;
344 		x[0].tx_buf = write_buf;
345 		spi_message_add_tail(&x[0], &message);
346 
347 		x[1].len = 4;
348 		x[1].tx_buf = write_buf;
349 		spi_message_add_tail(&x[1], &message);
350 
351 		x[2].len = end;
352 		x[2].rx_buf = rxbuf + offset;
353 		spi_message_add_tail(&x[2], &message);
354 
355 		status = spi_sync(rt5514_spi, &message);
356 
357 		if (status)
358 			return false;
359 
360 		offset += RT5514_SPI_BUF_LEN;
361 	}
362 
363 	for (i = 0; i < len; i += 8) {
364 		write_buf[0] = rxbuf[i + 0];
365 		write_buf[1] = rxbuf[i + 1];
366 		write_buf[2] = rxbuf[i + 2];
367 		write_buf[3] = rxbuf[i + 3];
368 		write_buf[4] = rxbuf[i + 4];
369 		write_buf[5] = rxbuf[i + 5];
370 		write_buf[6] = rxbuf[i + 6];
371 		write_buf[7] = rxbuf[i + 7];
372 
373 		rxbuf[i + 0] = write_buf[7];
374 		rxbuf[i + 1] = write_buf[6];
375 		rxbuf[i + 2] = write_buf[5];
376 		rxbuf[i + 3] = write_buf[4];
377 		rxbuf[i + 4] = write_buf[3];
378 		rxbuf[i + 5] = write_buf[2];
379 		rxbuf[i + 6] = write_buf[1];
380 		rxbuf[i + 7] = write_buf[0];
381 	}
382 
383 	return true;
384 }
385 EXPORT_SYMBOL_GPL(rt5514_spi_burst_read);
386 
387 /**
388  * rt5514_spi_burst_write - Write data to SPI by rt5514 address.
389  * @addr: Start address.
390  * @txbuf: Data Buffer for writng.
391  * @len: Data length, it must be a multiple of 8.
392  *
393  *
394  * Returns true for success.
395  */
396 int rt5514_spi_burst_write(u32 addr, const u8 *txbuf, size_t len)
397 {
398 	u8 spi_cmd = RT5514_SPI_CMD_BURST_WRITE;
399 	u8 *write_buf;
400 	unsigned int i, end, offset = 0;
401 
402 	write_buf = kmalloc(RT5514_SPI_BUF_LEN + 6, GFP_KERNEL);
403 
404 	if (write_buf == NULL)
405 		return -ENOMEM;
406 
407 	while (offset < len) {
408 		if (offset + RT5514_SPI_BUF_LEN <= len)
409 			end = RT5514_SPI_BUF_LEN;
410 		else
411 			end = len % RT5514_SPI_BUF_LEN;
412 
413 		write_buf[0] = spi_cmd;
414 		write_buf[1] = ((addr + offset) & 0xff000000) >> 24;
415 		write_buf[2] = ((addr + offset) & 0x00ff0000) >> 16;
416 		write_buf[3] = ((addr + offset) & 0x0000ff00) >> 8;
417 		write_buf[4] = ((addr + offset) & 0x000000ff) >> 0;
418 
419 		for (i = 0; i < end; i += 8) {
420 			write_buf[i + 12] = txbuf[offset + i + 0];
421 			write_buf[i + 11] = txbuf[offset + i + 1];
422 			write_buf[i + 10] = txbuf[offset + i + 2];
423 			write_buf[i +  9] = txbuf[offset + i + 3];
424 			write_buf[i +  8] = txbuf[offset + i + 4];
425 			write_buf[i +  7] = txbuf[offset + i + 5];
426 			write_buf[i +  6] = txbuf[offset + i + 6];
427 			write_buf[i +  5] = txbuf[offset + i + 7];
428 		}
429 
430 		write_buf[end + 5] = spi_cmd;
431 
432 		spi_write(rt5514_spi, write_buf, end + 6);
433 
434 		offset += RT5514_SPI_BUF_LEN;
435 	}
436 
437 	kfree(write_buf);
438 
439 	return 0;
440 }
441 EXPORT_SYMBOL_GPL(rt5514_spi_burst_write);
442 
443 static int rt5514_spi_probe(struct spi_device *spi)
444 {
445 	int ret;
446 
447 	rt5514_spi = spi;
448 
449 	ret = devm_snd_soc_register_component(&spi->dev,
450 					      &rt5514_spi_component,
451 					      &rt5514_spi_dai, 1);
452 	if (ret < 0) {
453 		dev_err(&spi->dev, "Failed to register component.\n");
454 		return ret;
455 	}
456 
457 	return 0;
458 }
459 
460 static int __maybe_unused rt5514_suspend(struct device *dev)
461 {
462 	int irq = to_spi_device(dev)->irq;
463 
464 	if (device_may_wakeup(dev))
465 		enable_irq_wake(irq);
466 
467 	return 0;
468 }
469 
470 static int __maybe_unused rt5514_resume(struct device *dev)
471 {
472 	struct snd_soc_component *component = snd_soc_lookup_component(dev, DRV_NAME);
473 	struct rt5514_dsp *rt5514_dsp =
474 		snd_soc_component_get_drvdata(component);
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