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
37static struct spi_device *rt5514_spi;
38
39struct 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
48static 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
62static 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
74static 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
151done:
152	mutex_unlock(&rt5514_dsp->dma_lock);
153}
154
155static 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
194static 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 */
204static 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
212static 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	u8 buf[8];
219
220	mutex_lock(&rt5514_dsp->dma_lock);
221	rt5514_dsp->substream = substream;
222	rt5514_dsp->dma_offset = 0;
223
224	/* Read IRQ status and schedule copy accordingly. */
225	rt5514_spi_burst_read(RT5514_IRQ_CTRL, (u8 *)&buf, sizeof(buf));
226	if (buf[0] & RT5514_IRQ_STATUS_BIT)
227		rt5514_schedule_copy(rt5514_dsp);
228
229	mutex_unlock(&rt5514_dsp->dma_lock);
230
231	return 0;
232}
233
234static int rt5514_spi_hw_free(struct snd_soc_component *component,
235			      struct snd_pcm_substream *substream)
236{
237	struct rt5514_dsp *rt5514_dsp =
238		snd_soc_component_get_drvdata(component);
239
240	mutex_lock(&rt5514_dsp->dma_lock);
241	rt5514_dsp->substream = NULL;
242	mutex_unlock(&rt5514_dsp->dma_lock);
243
244	cancel_delayed_work_sync(&rt5514_dsp->copy_work);
245
246	return 0;
247}
248
249static snd_pcm_uframes_t rt5514_spi_pcm_pointer(
250		struct snd_soc_component *component,
251		struct snd_pcm_substream *substream)
252{
253	struct snd_pcm_runtime *runtime = substream->runtime;
254	struct rt5514_dsp *rt5514_dsp =
255		snd_soc_component_get_drvdata(component);
256
257	return bytes_to_frames(runtime, rt5514_dsp->dma_offset);
258}
259
260
261static int rt5514_spi_pcm_probe(struct snd_soc_component *component)
262{
263	struct rt5514_dsp *rt5514_dsp;
264	int ret;
265
266	rt5514_dsp = devm_kzalloc(component->dev, sizeof(*rt5514_dsp),
267			GFP_KERNEL);
268	if (!rt5514_dsp)
269		return -ENOMEM;
270
271	rt5514_dsp->dev = &rt5514_spi->dev;
272	mutex_init(&rt5514_dsp->dma_lock);
273	INIT_DELAYED_WORK(&rt5514_dsp->copy_work, rt5514_spi_copy_work);
274	snd_soc_component_set_drvdata(component, rt5514_dsp);
275
276	if (rt5514_spi->irq) {
277		ret = devm_request_threaded_irq(&rt5514_spi->dev,
278			rt5514_spi->irq, NULL, rt5514_spi_irq,
279			IRQF_TRIGGER_RISING | IRQF_ONESHOT, "rt5514-spi",
280			rt5514_dsp);
281		if (ret)
282			dev_err(&rt5514_spi->dev,
283				"%s Failed to reguest IRQ: %d\n", __func__,
284				ret);
285		else
286			device_init_wakeup(rt5514_dsp->dev, true);
287	}
288
289	return 0;
290}
291
292static int rt5514_spi_pcm_new(struct snd_soc_component *component,
293			      struct snd_soc_pcm_runtime *rtd)
294{
295	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_VMALLOC,
296				       NULL, 0, 0);
297	return 0;
298}
299
300static const struct snd_soc_component_driver rt5514_spi_component = {
301	.name		= DRV_NAME,
302	.probe		= rt5514_spi_pcm_probe,
303	.open		= rt5514_spi_pcm_open,
304	.hw_params	= rt5514_spi_hw_params,
305	.hw_free	= rt5514_spi_hw_free,
306	.pointer	= rt5514_spi_pcm_pointer,
307	.pcm_construct	= rt5514_spi_pcm_new,
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