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 
aiu_fifo_dai(struct snd_pcm_substream * ss)26 static 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 
aiu_fifo_pointer(struct snd_soc_component * component,struct snd_pcm_substream * substream)33 snd_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 = snd_soc_dai_dma_data_get_playback(dai);
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 
aiu_fifo_enable(struct snd_soc_dai * dai,bool enable)46 static 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 = snd_soc_dai_dma_data_get_playback(dai);
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 
aiu_fifo_trigger(struct snd_pcm_substream * substream,int cmd,struct snd_soc_dai * dai)58 int 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 
aiu_fifo_prepare(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)79 int 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 = snd_soc_dai_dma_data_get_playback(dai);
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 
aiu_fifo_hw_params(struct snd_pcm_substream * substream,struct snd_pcm_hw_params * params,struct snd_soc_dai * dai)95 int 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 = snd_soc_dai_dma_data_get_playback(dai);
102 	dma_addr_t end;
103 
104 	/* Setup the fifo boundaries */
105 	end = runtime->dma_addr + runtime->dma_bytes - fifo->fifo_block;
106 	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_START,
107 				runtime->dma_addr);
108 	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_RD,
109 				runtime->dma_addr);
110 	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_END,
111 				end);
112 
113 	/* Setup the fifo to read all the memory - no skip */
114 	snd_soc_component_update_bits(component,
115 				      fifo->mem_offset + AIU_MEM_MASKS,
116 				      AIU_MEM_MASK_CH_RD | AIU_MEM_MASK_CH_MEM,
117 				      FIELD_PREP(AIU_MEM_MASK_CH_RD, 0xff) |
118 				      FIELD_PREP(AIU_MEM_MASK_CH_MEM, 0xff));
119 
120 	return 0;
121 }
122 
aiu_fifo_isr(int irq,void * dev_id)123 static irqreturn_t aiu_fifo_isr(int irq, void *dev_id)
124 {
125 	struct snd_pcm_substream *playback = dev_id;
126 
127 	snd_pcm_period_elapsed(playback);
128 
129 	return IRQ_HANDLED;
130 }
131 
aiu_fifo_startup(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)132 int aiu_fifo_startup(struct snd_pcm_substream *substream,
133 		     struct snd_soc_dai *dai)
134 {
135 	struct aiu_fifo *fifo = snd_soc_dai_dma_data_get_playback(dai);
136 	int ret;
137 
138 	snd_soc_set_runtime_hwparams(substream, fifo->pcm);
139 
140 	/*
141 	 * Make sure the buffer and period size are multiple of the fifo burst
142 	 * size
143 	 */
144 	ret = snd_pcm_hw_constraint_step(substream->runtime, 0,
145 					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
146 					 fifo->fifo_block);
147 	if (ret)
148 		return ret;
149 
150 	ret = snd_pcm_hw_constraint_step(substream->runtime, 0,
151 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
152 					 fifo->fifo_block);
153 	if (ret)
154 		return ret;
155 
156 	ret = clk_prepare_enable(fifo->pclk);
157 	if (ret)
158 		return ret;
159 
160 	ret = request_irq(fifo->irq, aiu_fifo_isr, 0, dev_name(dai->dev),
161 			  substream);
162 	if (ret)
163 		clk_disable_unprepare(fifo->pclk);
164 
165 	return ret;
166 }
167 
aiu_fifo_shutdown(struct snd_pcm_substream * substream,struct snd_soc_dai * dai)168 void aiu_fifo_shutdown(struct snd_pcm_substream *substream,
169 		       struct snd_soc_dai *dai)
170 {
171 	struct aiu_fifo *fifo = snd_soc_dai_dma_data_get_playback(dai);
172 
173 	free_irq(fifo->irq, substream);
174 	clk_disable_unprepare(fifo->pclk);
175 }
176 
aiu_fifo_pcm_new(struct snd_soc_pcm_runtime * rtd,struct snd_soc_dai * dai)177 int aiu_fifo_pcm_new(struct snd_soc_pcm_runtime *rtd,
178 		     struct snd_soc_dai *dai)
179 {
180 	struct snd_card *card = rtd->card->snd_card;
181 	struct aiu_fifo *fifo = snd_soc_dai_dma_data_get_playback(dai);
182 	size_t size = fifo->pcm->buffer_bytes_max;
183 	int ret;
184 
185 	ret = dma_coerce_mask_and_coherent(card->dev, DMA_BIT_MASK(32));
186 	if (ret)
187 		return ret;
188 
189 	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
190 				       card->dev, size, size);
191 
192 	return 0;
193 }
194 
aiu_fifo_dai_probe(struct snd_soc_dai * dai)195 int aiu_fifo_dai_probe(struct snd_soc_dai *dai)
196 {
197 	struct aiu_fifo *fifo;
198 
199 	fifo = kzalloc(sizeof(*fifo), GFP_KERNEL);
200 	if (!fifo)
201 		return -ENOMEM;
202 
203 	snd_soc_dai_dma_data_set_playback(dai, fifo);
204 
205 	return 0;
206 }
207 
aiu_fifo_dai_remove(struct snd_soc_dai * dai)208 int aiu_fifo_dai_remove(struct snd_soc_dai *dai)
209 {
210 	struct aiu_fifo *fifo = snd_soc_dai_dma_data_get_playback(dai);
211 
212 	kfree(fifo);
213 
214 	return 0;
215 }
216