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
36static struct spi_device *rt5514_spi;
37
38struct 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
47static 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
61static 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
73static 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
150done:
151	mutex_unlock(&rt5514_dsp->dma_lock);
152}
153
154static 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
193static 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 */
203static 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
211static 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
233static 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
248static 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
260static 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 request IRQ: %d\n", __func__,
283				ret);
284		else
285			device_init_wakeup(rt5514_dsp->dev, true);
286	}
287
288	return 0;
289}
290
291static 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
299static 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 */
319int 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}
386EXPORT_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 */
397int 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}
442EXPORT_SYMBOL_GPL(rt5514_spi_burst_write);
443
444static 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
461static 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
471static 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
492static const struct dev_pm_ops rt5514_pm_ops = {
493	SET_SYSTEM_SLEEP_PM_OPS(rt5514_suspend, rt5514_resume)
494};
495
496static const struct of_device_id rt5514_of_match[] = {
497	{ .compatible = "realtek,rt5514", },
498	{},
499};
500MODULE_DEVICE_TABLE(of, rt5514_of_match);
501
502static 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};
510module_spi_driver(rt5514_spi_driver);
511
512MODULE_DESCRIPTION("RT5514 SPI driver");
513MODULE_AUTHOR("Oder Chiou <oder_chiou@realtek.com>");
514MODULE_LICENSE("GPL v2");
515