1// SPDX-License-Identifier: GPL-2.0+
2//
3// AMD ALSA SoC PDM Driver
4//
5//Copyright 2020 Advanced Micro Devices, Inc.
6
7#include <linux/platform_device.h>
8#include <linux/module.h>
9#include <linux/bitfield.h>
10#include <linux/err.h>
11#include <linux/io.h>
12#include <linux/pm_runtime.h>
13#include <sound/pcm_params.h>
14#include <sound/soc.h>
15#include <sound/soc-dai.h>
16
17#include "rn_acp3x.h"
18
19#define DRV_NAME "acp_rn_pdm_dma"
20
21static int pdm_gain = 3;
22module_param(pdm_gain, int, 0644);
23MODULE_PARM_DESC(pdm_gain, "Gain control (0-3)");
24
25static const struct snd_pcm_hardware acp_pdm_hardware_capture = {
26	.info = SNDRV_PCM_INFO_INTERLEAVED |
27		SNDRV_PCM_INFO_BLOCK_TRANSFER |
28		SNDRV_PCM_INFO_MMAP |
29		SNDRV_PCM_INFO_MMAP_VALID |
30		SNDRV_PCM_INFO_PAUSE | SNDRV_PCM_INFO_RESUME,
31	.formats = SNDRV_PCM_FMTBIT_S32_LE,
32	.channels_min = 2,
33	.channels_max = 2,
34	.rates = SNDRV_PCM_RATE_48000,
35	.rate_min = 48000,
36	.rate_max = 48000,
37	.buffer_bytes_max = CAPTURE_MAX_NUM_PERIODS * CAPTURE_MAX_PERIOD_SIZE,
38	.period_bytes_min = CAPTURE_MIN_PERIOD_SIZE,
39	.period_bytes_max = CAPTURE_MAX_PERIOD_SIZE,
40	.periods_min = CAPTURE_MIN_NUM_PERIODS,
41	.periods_max = CAPTURE_MAX_NUM_PERIODS,
42};
43
44static irqreturn_t pdm_irq_handler(int irq, void *dev_id)
45{
46	struct pdm_dev_data *rn_pdm_data;
47	u16 cap_flag;
48	u32 val;
49
50	rn_pdm_data = dev_id;
51	if (!rn_pdm_data)
52		return IRQ_NONE;
53
54	cap_flag = 0;
55	val = rn_readl(rn_pdm_data->acp_base + ACP_EXTERNAL_INTR_STAT);
56	if ((val & BIT(PDM_DMA_STAT)) && rn_pdm_data->capture_stream) {
57		rn_writel(BIT(PDM_DMA_STAT), rn_pdm_data->acp_base +
58			  ACP_EXTERNAL_INTR_STAT);
59		snd_pcm_period_elapsed(rn_pdm_data->capture_stream);
60		cap_flag = 1;
61	}
62
63	if (cap_flag)
64		return IRQ_HANDLED;
65	else
66		return IRQ_NONE;
67}
68
69static void init_pdm_ring_buffer(u32 physical_addr,
70				 u32 buffer_size,
71				 u32 watermark_size,
72				 void __iomem *acp_base)
73{
74	rn_writel(physical_addr, acp_base + ACP_WOV_RX_RINGBUFADDR);
75	rn_writel(buffer_size, acp_base + ACP_WOV_RX_RINGBUFSIZE);
76	rn_writel(watermark_size, acp_base + ACP_WOV_RX_INTR_WATERMARK_SIZE);
77	rn_writel(0x01, acp_base + ACPAXI2AXI_ATU_CTRL);
78}
79
80static void enable_pdm_clock(void __iomem *acp_base)
81{
82	u32 pdm_clk_enable, pdm_ctrl;
83
84	pdm_clk_enable = ACP_PDM_CLK_FREQ_MASK;
85
86	rn_writel(pdm_clk_enable, acp_base + ACP_WOV_CLK_CTRL);
87	pdm_ctrl = rn_readl(acp_base + ACP_WOV_MISC_CTRL);
88	pdm_ctrl &= ~ACP_WOV_GAIN_CONTROL;
89	pdm_ctrl |= FIELD_PREP(ACP_WOV_GAIN_CONTROL, clamp(pdm_gain, 0, 3));
90	rn_writel(pdm_ctrl, acp_base + ACP_WOV_MISC_CTRL);
91}
92
93static void enable_pdm_interrupts(void __iomem *acp_base)
94{
95	u32 ext_int_ctrl;
96
97	ext_int_ctrl = rn_readl(acp_base + ACP_EXTERNAL_INTR_CNTL);
98	ext_int_ctrl |= PDM_DMA_INTR_MASK;
99	rn_writel(ext_int_ctrl, acp_base + ACP_EXTERNAL_INTR_CNTL);
100}
101
102static void disable_pdm_interrupts(void __iomem *acp_base)
103{
104	u32 ext_int_ctrl;
105
106	ext_int_ctrl = rn_readl(acp_base + ACP_EXTERNAL_INTR_CNTL);
107	ext_int_ctrl |= ~PDM_DMA_INTR_MASK;
108	rn_writel(ext_int_ctrl, acp_base + ACP_EXTERNAL_INTR_CNTL);
109}
110
111static bool check_pdm_dma_status(void __iomem *acp_base)
112{
113	bool pdm_dma_status;
114	u32 pdm_enable, pdm_dma_enable;
115
116	pdm_dma_status = false;
117	pdm_enable = rn_readl(acp_base + ACP_WOV_PDM_ENABLE);
118	pdm_dma_enable = rn_readl(acp_base + ACP_WOV_PDM_DMA_ENABLE);
119	if ((pdm_enable & ACP_PDM_ENABLE) && (pdm_dma_enable &
120	     ACP_PDM_DMA_EN_STATUS))
121		pdm_dma_status = true;
122	return pdm_dma_status;
123}
124
125static int start_pdm_dma(void __iomem *acp_base)
126{
127	u32 pdm_enable;
128	u32 pdm_dma_enable;
129	int timeout;
130
131	pdm_enable = 0x01;
132	pdm_dma_enable  = 0x01;
133
134	enable_pdm_clock(acp_base);
135	rn_writel(pdm_enable, acp_base + ACP_WOV_PDM_ENABLE);
136	rn_writel(pdm_dma_enable, acp_base + ACP_WOV_PDM_DMA_ENABLE);
137	timeout = 0;
138	while (++timeout < ACP_COUNTER) {
139		pdm_dma_enable = rn_readl(acp_base + ACP_WOV_PDM_DMA_ENABLE);
140		if ((pdm_dma_enable & 0x02) == ACP_PDM_DMA_EN_STATUS)
141			return 0;
142		udelay(DELAY_US);
143	}
144	return -ETIMEDOUT;
145}
146
147static int stop_pdm_dma(void __iomem *acp_base)
148{
149	u32 pdm_enable, pdm_dma_enable;
150	int timeout;
151
152	pdm_enable = rn_readl(acp_base + ACP_WOV_PDM_ENABLE);
153	pdm_dma_enable = rn_readl(acp_base + ACP_WOV_PDM_DMA_ENABLE);
154	if (pdm_dma_enable & 0x01) {
155		pdm_dma_enable = 0x02;
156		rn_writel(pdm_dma_enable, acp_base + ACP_WOV_PDM_DMA_ENABLE);
157		timeout = 0;
158		while (++timeout < ACP_COUNTER) {
159			pdm_dma_enable = rn_readl(acp_base +
160						  ACP_WOV_PDM_DMA_ENABLE);
161			if ((pdm_dma_enable & 0x02) == 0x00)
162				break;
163			udelay(DELAY_US);
164		}
165		if (timeout == ACP_COUNTER)
166			return -ETIMEDOUT;
167	}
168	if (pdm_enable == ACP_PDM_ENABLE) {
169		pdm_enable = ACP_PDM_DISABLE;
170		rn_writel(pdm_enable, acp_base + ACP_WOV_PDM_ENABLE);
171	}
172	rn_writel(0x01, acp_base + ACP_WOV_PDM_FIFO_FLUSH);
173	return 0;
174}
175
176static void config_acp_dma(struct pdm_stream_instance *rtd, int direction)
177{
178	u16 page_idx;
179	u32 low, high, val;
180	dma_addr_t addr;
181
182	addr = rtd->dma_addr;
183	val = 0;
184
185	/* Group Enable */
186	rn_writel(ACP_SRAM_PTE_OFFSET | BIT(31), rtd->acp_base +
187		  ACPAXI2AXI_ATU_BASE_ADDR_GRP_1);
188	rn_writel(PAGE_SIZE_4K_ENABLE, rtd->acp_base +
189		  ACPAXI2AXI_ATU_PAGE_SIZE_GRP_1);
190
191	for (page_idx = 0; page_idx < rtd->num_pages; page_idx++) {
192		/* Load the low address of page int ACP SRAM through SRBM */
193		low = lower_32_bits(addr);
194		high = upper_32_bits(addr);
195
196		rn_writel(low, rtd->acp_base + ACP_SCRATCH_REG_0 + val);
197		high |= BIT(31);
198		rn_writel(high, rtd->acp_base + ACP_SCRATCH_REG_0 + val + 4);
199		val += 8;
200		addr += PAGE_SIZE;
201	}
202}
203
204static int acp_pdm_dma_open(struct snd_soc_component *component,
205			    struct snd_pcm_substream *substream)
206{
207	struct snd_pcm_runtime *runtime;
208	struct pdm_dev_data *adata;
209	struct pdm_stream_instance *pdm_data;
210	int ret;
211
212	runtime = substream->runtime;
213	adata = dev_get_drvdata(component->dev);
214	pdm_data = kzalloc(sizeof(*pdm_data), GFP_KERNEL);
215	if (!pdm_data)
216		return -EINVAL;
217
218	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
219		runtime->hw = acp_pdm_hardware_capture;
220
221	ret = snd_pcm_hw_constraint_integer(runtime,
222					    SNDRV_PCM_HW_PARAM_PERIODS);
223	if (ret < 0) {
224		dev_err(component->dev, "set integer constraint failed\n");
225		kfree(pdm_data);
226		return ret;
227	}
228
229	enable_pdm_interrupts(adata->acp_base);
230
231	if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
232		adata->capture_stream = substream;
233
234	pdm_data->acp_base = adata->acp_base;
235	runtime->private_data = pdm_data;
236	return ret;
237}
238
239static int acp_pdm_dma_hw_params(struct snd_soc_component *component,
240				 struct snd_pcm_substream *substream,
241				 struct snd_pcm_hw_params *params)
242{
243	struct pdm_stream_instance *rtd;
244	size_t size, period_bytes;
245
246	rtd = substream->runtime->private_data;
247	if (!rtd)
248		return -EINVAL;
249	size = params_buffer_bytes(params);
250	period_bytes = params_period_bytes(params);
251	rtd->dma_addr = substream->runtime->dma_addr;
252	rtd->num_pages = (PAGE_ALIGN(size) >> PAGE_SHIFT);
253	config_acp_dma(rtd, substream->stream);
254	init_pdm_ring_buffer(MEM_WINDOW_START, size, period_bytes,
255			     rtd->acp_base);
256	return 0;
257}
258
259static u64 acp_pdm_get_byte_count(struct pdm_stream_instance *rtd,
260				  int direction)
261{
262	union acp_pdm_dma_count byte_count;
263
264	byte_count.bcount.high =
265			rn_readl(rtd->acp_base +
266				 ACP_WOV_RX_LINEARPOSITIONCNTR_HIGH);
267	byte_count.bcount.low =
268			rn_readl(rtd->acp_base +
269				 ACP_WOV_RX_LINEARPOSITIONCNTR_LOW);
270	return byte_count.bytescount;
271}
272
273static snd_pcm_uframes_t acp_pdm_dma_pointer(struct snd_soc_component *comp,
274					     struct snd_pcm_substream *stream)
275{
276	struct pdm_stream_instance *rtd;
277	u32 pos, buffersize;
278	u64 bytescount;
279
280	rtd = stream->runtime->private_data;
281	buffersize = frames_to_bytes(stream->runtime,
282				     stream->runtime->buffer_size);
283	bytescount = acp_pdm_get_byte_count(rtd, stream->stream);
284	if (bytescount > rtd->bytescount)
285		bytescount -= rtd->bytescount;
286	pos = do_div(bytescount, buffersize);
287	return bytes_to_frames(stream->runtime, pos);
288}
289
290static int acp_pdm_dma_new(struct snd_soc_component *component,
291			   struct snd_soc_pcm_runtime *rtd)
292{
293	struct device *parent = component->dev->parent;
294
295	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
296				       parent, MIN_BUFFER, MAX_BUFFER);
297	return 0;
298}
299
300static int acp_pdm_dma_close(struct snd_soc_component *component,
301			     struct snd_pcm_substream *substream)
302{
303	struct pdm_dev_data *adata = dev_get_drvdata(component->dev);
304
305	disable_pdm_interrupts(adata->acp_base);
306	adata->capture_stream = NULL;
307	return 0;
308}
309
310static int acp_pdm_dai_trigger(struct snd_pcm_substream *substream,
311			       int cmd, struct snd_soc_dai *dai)
312{
313	struct pdm_stream_instance *rtd;
314	int ret;
315	bool pdm_status;
316	unsigned int ch_mask;
317
318	rtd = substream->runtime->private_data;
319	ret = 0;
320	switch (substream->runtime->channels) {
321	case TWO_CH:
322		ch_mask = 0x00;
323		break;
324	default:
325		return -EINVAL;
326	}
327	switch (cmd) {
328	case SNDRV_PCM_TRIGGER_START:
329	case SNDRV_PCM_TRIGGER_RESUME:
330	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
331		rn_writel(ch_mask, rtd->acp_base + ACP_WOV_PDM_NO_OF_CHANNELS);
332		rn_writel(PDM_DECIMATION_FACTOR, rtd->acp_base +
333			  ACP_WOV_PDM_DECIMATION_FACTOR);
334		rtd->bytescount = acp_pdm_get_byte_count(rtd,
335							 substream->stream);
336		pdm_status = check_pdm_dma_status(rtd->acp_base);
337		if (!pdm_status)
338			ret = start_pdm_dma(rtd->acp_base);
339		break;
340	case SNDRV_PCM_TRIGGER_STOP:
341	case SNDRV_PCM_TRIGGER_SUSPEND:
342	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
343		pdm_status = check_pdm_dma_status(rtd->acp_base);
344		if (pdm_status)
345			ret = stop_pdm_dma(rtd->acp_base);
346		break;
347	default:
348		ret = -EINVAL;
349		break;
350	}
351	return ret;
352}
353
354static const struct snd_soc_dai_ops acp_pdm_dai_ops = {
355	.trigger   = acp_pdm_dai_trigger,
356};
357
358static struct snd_soc_dai_driver acp_pdm_dai_driver = {
359	.capture = {
360		.rates = SNDRV_PCM_RATE_48000,
361		.formats = SNDRV_PCM_FMTBIT_S24_LE |
362			   SNDRV_PCM_FMTBIT_S32_LE,
363		.channels_min = 2,
364		.channels_max = 2,
365		.rate_min = 48000,
366		.rate_max = 48000,
367	},
368	.ops = &acp_pdm_dai_ops,
369};
370
371static const struct snd_soc_component_driver acp_pdm_component = {
372	.name			= DRV_NAME,
373	.open			= acp_pdm_dma_open,
374	.close			= acp_pdm_dma_close,
375	.hw_params		= acp_pdm_dma_hw_params,
376	.pointer		= acp_pdm_dma_pointer,
377	.pcm_construct		= acp_pdm_dma_new,
378	.legacy_dai_naming	= 1,
379};
380
381static int acp_pdm_audio_probe(struct platform_device *pdev)
382{
383	struct resource *res;
384	struct pdm_dev_data *adata;
385	unsigned int irqflags;
386	int status;
387
388	if (!pdev->dev.platform_data) {
389		dev_err(&pdev->dev, "platform_data not retrieved\n");
390		return -ENODEV;
391	}
392	irqflags = *((unsigned int *)(pdev->dev.platform_data));
393
394	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
395	if (!res) {
396		dev_err(&pdev->dev, "IORESOURCE_MEM FAILED\n");
397		return -ENODEV;
398	}
399
400	adata = devm_kzalloc(&pdev->dev, sizeof(*adata), GFP_KERNEL);
401	if (!adata)
402		return -ENOMEM;
403
404	adata->acp_base = devm_ioremap(&pdev->dev, res->start,
405				       resource_size(res));
406	if (!adata->acp_base)
407		return -ENOMEM;
408
409	status = platform_get_irq(pdev, 0);
410	if (status < 0)
411		return status;
412	adata->pdm_irq = status;
413
414	adata->capture_stream = NULL;
415
416	dev_set_drvdata(&pdev->dev, adata);
417	status = devm_snd_soc_register_component(&pdev->dev,
418						 &acp_pdm_component,
419						 &acp_pdm_dai_driver, 1);
420	if (status) {
421		dev_err(&pdev->dev, "Fail to register acp pdm dai\n");
422
423		return -ENODEV;
424	}
425	status = devm_request_irq(&pdev->dev, adata->pdm_irq, pdm_irq_handler,
426				  irqflags, "ACP_PDM_IRQ", adata);
427	if (status) {
428		dev_err(&pdev->dev, "ACP PDM IRQ request failed\n");
429		return -ENODEV;
430	}
431	pm_runtime_set_autosuspend_delay(&pdev->dev, ACP_SUSPEND_DELAY_MS);
432	pm_runtime_use_autosuspend(&pdev->dev);
433	pm_runtime_mark_last_busy(&pdev->dev);
434	pm_runtime_set_active(&pdev->dev);
435	pm_runtime_enable(&pdev->dev);
436	return 0;
437}
438
439static void acp_pdm_audio_remove(struct platform_device *pdev)
440{
441	pm_runtime_disable(&pdev->dev);
442}
443
444static int acp_pdm_resume(struct device *dev)
445{
446	struct pdm_dev_data *adata;
447	struct snd_pcm_runtime *runtime;
448	struct pdm_stream_instance *rtd;
449	u32 period_bytes, buffer_len;
450
451	adata = dev_get_drvdata(dev);
452	if (adata->capture_stream && adata->capture_stream->runtime) {
453		runtime = adata->capture_stream->runtime;
454		rtd = runtime->private_data;
455		period_bytes = frames_to_bytes(runtime, runtime->period_size);
456		buffer_len = frames_to_bytes(runtime, runtime->buffer_size);
457		config_acp_dma(rtd, SNDRV_PCM_STREAM_CAPTURE);
458		init_pdm_ring_buffer(MEM_WINDOW_START, buffer_len, period_bytes,
459				     adata->acp_base);
460	}
461	enable_pdm_interrupts(adata->acp_base);
462	return 0;
463}
464
465static int acp_pdm_runtime_suspend(struct device *dev)
466{
467	struct pdm_dev_data *adata;
468
469	adata = dev_get_drvdata(dev);
470	disable_pdm_interrupts(adata->acp_base);
471
472	return 0;
473}
474
475static int acp_pdm_runtime_resume(struct device *dev)
476{
477	struct pdm_dev_data *adata;
478
479	adata = dev_get_drvdata(dev);
480	enable_pdm_interrupts(adata->acp_base);
481	return 0;
482}
483
484static const struct dev_pm_ops acp_pdm_pm_ops = {
485	.runtime_suspend = acp_pdm_runtime_suspend,
486	.runtime_resume = acp_pdm_runtime_resume,
487	.resume = acp_pdm_resume,
488};
489
490static struct platform_driver acp_pdm_dma_driver = {
491	.probe = acp_pdm_audio_probe,
492	.remove_new = acp_pdm_audio_remove,
493	.driver = {
494		.name = "acp_rn_pdm_dma",
495		.pm = &acp_pdm_pm_ops,
496	},
497};
498
499module_platform_driver(acp_pdm_dma_driver);
500
501MODULE_AUTHOR("Vijendar.Mukunda@amd.com");
502MODULE_DESCRIPTION("AMD ACP3x Renior PDM Driver");
503MODULE_LICENSE("GPL v2");
504MODULE_ALIAS("platform:" DRV_NAME);
505