1// SPDX-License-Identifier: GPL-2.0
2//
3// Copyright (c) 2020 BayLibre, SAS.
4// Author: Jerome Brunet <jbrunet@baylibre.com>
5
6#include <linux/bitfield.h>
7#include <linux/clk.h>
8#include <linux/dma-mapping.h>
9#include <sound/pcm_params.h>
10#include <sound/soc.h>
11#include <sound/soc-dai.h>
12
13#include "aiu-fifo.h"
14
15#define AIU_MEM_START	0x00
16#define AIU_MEM_RD	0x04
17#define AIU_MEM_END	0x08
18#define AIU_MEM_MASKS	0x0c
19#define  AIU_MEM_MASK_CH_RD GENMASK(7, 0)
20#define  AIU_MEM_MASK_CH_MEM GENMASK(15, 8)
21#define AIU_MEM_CONTROL	0x10
22#define  AIU_MEM_CONTROL_INIT BIT(0)
23#define  AIU_MEM_CONTROL_FILL_EN BIT(1)
24#define  AIU_MEM_CONTROL_EMPTY_EN BIT(2)
25
26static struct snd_soc_dai *aiu_fifo_dai(struct snd_pcm_substream *ss)
27{
28	struct snd_soc_pcm_runtime *rtd = ss->private_data;
29
30	return asoc_rtd_to_cpu(rtd, 0);
31}
32
33snd_pcm_uframes_t aiu_fifo_pointer(struct snd_soc_component *component,
34				   struct snd_pcm_substream *substream)
35{
36	struct snd_soc_dai *dai = aiu_fifo_dai(substream);
37	struct aiu_fifo *fifo = dai->playback_dma_data;
38	struct snd_pcm_runtime *runtime = substream->runtime;
39	unsigned int addr;
40
41	addr = snd_soc_component_read(component, fifo->mem_offset + AIU_MEM_RD);
42
43	return bytes_to_frames(runtime, addr - (unsigned int)runtime->dma_addr);
44}
45
46static void aiu_fifo_enable(struct snd_soc_dai *dai, bool enable)
47{
48	struct snd_soc_component *component = dai->component;
49	struct aiu_fifo *fifo = dai->playback_dma_data;
50	unsigned int en_mask = (AIU_MEM_CONTROL_FILL_EN |
51				AIU_MEM_CONTROL_EMPTY_EN);
52
53	snd_soc_component_update_bits(component,
54				      fifo->mem_offset + AIU_MEM_CONTROL,
55				      en_mask, enable ? en_mask : 0);
56}
57
58int aiu_fifo_trigger(struct snd_pcm_substream *substream, int cmd,
59		     struct snd_soc_dai *dai)
60{
61	switch (cmd) {
62	case SNDRV_PCM_TRIGGER_START:
63	case SNDRV_PCM_TRIGGER_RESUME:
64	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
65		aiu_fifo_enable(dai, true);
66		break;
67	case SNDRV_PCM_TRIGGER_SUSPEND:
68	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
69	case SNDRV_PCM_TRIGGER_STOP:
70		aiu_fifo_enable(dai, false);
71		break;
72	default:
73		return -EINVAL;
74	}
75
76	return 0;
77}
78
79int aiu_fifo_prepare(struct snd_pcm_substream *substream,
80		     struct snd_soc_dai *dai)
81{
82	struct snd_soc_component *component = dai->component;
83	struct aiu_fifo *fifo = dai->playback_dma_data;
84
85	snd_soc_component_update_bits(component,
86				      fifo->mem_offset + AIU_MEM_CONTROL,
87				      AIU_MEM_CONTROL_INIT,
88				      AIU_MEM_CONTROL_INIT);
89	snd_soc_component_update_bits(component,
90				      fifo->mem_offset + AIU_MEM_CONTROL,
91				      AIU_MEM_CONTROL_INIT, 0);
92	return 0;
93}
94
95int aiu_fifo_hw_params(struct snd_pcm_substream *substream,
96		       struct snd_pcm_hw_params *params,
97		       struct snd_soc_dai *dai)
98{
99	struct snd_pcm_runtime *runtime = substream->runtime;
100	struct snd_soc_component *component = dai->component;
101	struct aiu_fifo *fifo = dai->playback_dma_data;
102	dma_addr_t end;
103	int ret;
104
105	ret = snd_pcm_lib_malloc_pages(substream, params_buffer_bytes(params));
106	if (ret < 0)
107		return ret;
108
109	/* Setup the fifo boundaries */
110	end = runtime->dma_addr + runtime->dma_bytes - fifo->fifo_block;
111	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_START,
112				runtime->dma_addr);
113	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_RD,
114				runtime->dma_addr);
115	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_END,
116				end);
117
118	/* Setup the fifo to read all the memory - no skip */
119	snd_soc_component_update_bits(component,
120				      fifo->mem_offset + AIU_MEM_MASKS,
121				      AIU_MEM_MASK_CH_RD | AIU_MEM_MASK_CH_MEM,
122				      FIELD_PREP(AIU_MEM_MASK_CH_RD, 0xff) |
123				      FIELD_PREP(AIU_MEM_MASK_CH_MEM, 0xff));
124
125	return 0;
126}
127
128int aiu_fifo_hw_free(struct snd_pcm_substream *substream,
129		     struct snd_soc_dai *dai)
130{
131	return snd_pcm_lib_free_pages(substream);
132}
133
134static irqreturn_t aiu_fifo_isr(int irq, void *dev_id)
135{
136	struct snd_pcm_substream *playback = dev_id;
137
138	snd_pcm_period_elapsed(playback);
139
140	return IRQ_HANDLED;
141}
142
143int aiu_fifo_startup(struct snd_pcm_substream *substream,
144		     struct snd_soc_dai *dai)
145{
146	struct aiu_fifo *fifo = dai->playback_dma_data;
147	int ret;
148
149	snd_soc_set_runtime_hwparams(substream, fifo->pcm);
150
151	/*
152	 * Make sure the buffer and period size are multiple of the fifo burst
153	 * size
154	 */
155	ret = snd_pcm_hw_constraint_step(substream->runtime, 0,
156					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
157					 fifo->fifo_block);
158	if (ret)
159		return ret;
160
161	ret = snd_pcm_hw_constraint_step(substream->runtime, 0,
162					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
163					 fifo->fifo_block);
164	if (ret)
165		return ret;
166
167	ret = clk_prepare_enable(fifo->pclk);
168	if (ret)
169		return ret;
170
171	ret = request_irq(fifo->irq, aiu_fifo_isr, 0, dev_name(dai->dev),
172			  substream);
173	if (ret)
174		clk_disable_unprepare(fifo->pclk);
175
176	return ret;
177}
178
179void aiu_fifo_shutdown(struct snd_pcm_substream *substream,
180		       struct snd_soc_dai *dai)
181{
182	struct aiu_fifo *fifo = dai->playback_dma_data;
183
184	free_irq(fifo->irq, substream);
185	clk_disable_unprepare(fifo->pclk);
186}
187
188int aiu_fifo_pcm_new(struct snd_soc_pcm_runtime *rtd,
189		     struct snd_soc_dai *dai)
190{
191	struct snd_pcm_substream *substream =
192		rtd->pcm->streams[SNDRV_PCM_STREAM_PLAYBACK].substream;
193	struct snd_card *card = rtd->card->snd_card;
194	struct aiu_fifo *fifo = dai->playback_dma_data;
195	size_t size = fifo->pcm->buffer_bytes_max;
196	int ret;
197
198	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
199	if (ret)
200		return ret;
201
202	snd_pcm_lib_preallocate_pages(substream,
203				      SNDRV_DMA_TYPE_DEV,
204				      card->dev, size, size);
205
206	return 0;
207}
208
209int aiu_fifo_dai_probe(struct snd_soc_dai *dai)
210{
211	struct aiu_fifo *fifo;
212
213	fifo = kzalloc(sizeof(*fifo), GFP_KERNEL);
214	if (!fifo)
215		return -ENOMEM;
216
217	dai->playback_dma_data = fifo;
218
219	return 0;
220}
221
222int aiu_fifo_dai_remove(struct snd_soc_dai *dai)
223{
224	kfree(dai->playback_dma_data);
225
226	return 0;
227}
228
229