xref: /openbmc/linux/sound/soc/meson/aiu-fifo.c (revision 413d6ed3)
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 <sound/pcm_params.h>
9 #include <sound/soc.h>
10 #include <sound/soc-dai.h>
11 
12 #include "aiu-fifo.h"
13 
14 #define AIU_MEM_START	0x00
15 #define AIU_MEM_RD	0x04
16 #define AIU_MEM_END	0x08
17 #define AIU_MEM_MASKS	0x0c
18 #define  AIU_MEM_MASK_CH_RD GENMASK(7, 0)
19 #define  AIU_MEM_MASK_CH_MEM GENMASK(15, 8)
20 #define AIU_MEM_CONTROL	0x10
21 #define  AIU_MEM_CONTROL_INIT BIT(0)
22 #define  AIU_MEM_CONTROL_FILL_EN BIT(1)
23 #define  AIU_MEM_CONTROL_EMPTY_EN BIT(2)
24 
25 static struct snd_soc_dai *aiu_fifo_dai(struct snd_pcm_substream *ss)
26 {
27 	struct snd_soc_pcm_runtime *rtd = ss->private_data;
28 
29 	return asoc_rtd_to_cpu(rtd, 0);
30 }
31 
32 snd_pcm_uframes_t aiu_fifo_pointer(struct snd_soc_component *component,
33 				   struct snd_pcm_substream *substream)
34 {
35 	struct snd_soc_dai *dai = aiu_fifo_dai(substream);
36 	struct aiu_fifo *fifo = dai->playback_dma_data;
37 	struct snd_pcm_runtime *runtime = substream->runtime;
38 	unsigned int addr;
39 
40 	addr = snd_soc_component_read(component, fifo->mem_offset + AIU_MEM_RD);
41 
42 	return bytes_to_frames(runtime, addr - (unsigned int)runtime->dma_addr);
43 }
44 
45 static void aiu_fifo_enable(struct snd_soc_dai *dai, bool enable)
46 {
47 	struct snd_soc_component *component = dai->component;
48 	struct aiu_fifo *fifo = dai->playback_dma_data;
49 	unsigned int en_mask = (AIU_MEM_CONTROL_FILL_EN |
50 				AIU_MEM_CONTROL_EMPTY_EN);
51 
52 	snd_soc_component_update_bits(component,
53 				      fifo->mem_offset + AIU_MEM_CONTROL,
54 				      en_mask, enable ? en_mask : 0);
55 }
56 
57 int aiu_fifo_trigger(struct snd_pcm_substream *substream, int cmd,
58 		     struct snd_soc_dai *dai)
59 {
60 	switch (cmd) {
61 	case SNDRV_PCM_TRIGGER_START:
62 	case SNDRV_PCM_TRIGGER_RESUME:
63 	case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
64 		aiu_fifo_enable(dai, true);
65 		break;
66 	case SNDRV_PCM_TRIGGER_SUSPEND:
67 	case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
68 	case SNDRV_PCM_TRIGGER_STOP:
69 		aiu_fifo_enable(dai, false);
70 		break;
71 	default:
72 		return -EINVAL;
73 	}
74 
75 	return 0;
76 }
77 
78 int aiu_fifo_prepare(struct snd_pcm_substream *substream,
79 		     struct snd_soc_dai *dai)
80 {
81 	struct snd_soc_component *component = dai->component;
82 	struct aiu_fifo *fifo = dai->playback_dma_data;
83 
84 	snd_soc_component_update_bits(component,
85 				      fifo->mem_offset + AIU_MEM_CONTROL,
86 				      AIU_MEM_CONTROL_INIT,
87 				      AIU_MEM_CONTROL_INIT);
88 	snd_soc_component_update_bits(component,
89 				      fifo->mem_offset + AIU_MEM_CONTROL,
90 				      AIU_MEM_CONTROL_INIT, 0);
91 	return 0;
92 }
93 
94 int aiu_fifo_hw_params(struct snd_pcm_substream *substream,
95 		       struct snd_pcm_hw_params *params,
96 		       struct snd_soc_dai *dai)
97 {
98 	struct snd_pcm_runtime *runtime = substream->runtime;
99 	struct snd_soc_component *component = dai->component;
100 	struct aiu_fifo *fifo = dai->playback_dma_data;
101 	dma_addr_t end;
102 
103 	/* Setup the fifo boundaries */
104 	end = runtime->dma_addr + runtime->dma_bytes - fifo->fifo_block;
105 	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_START,
106 				runtime->dma_addr);
107 	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_RD,
108 				runtime->dma_addr);
109 	snd_soc_component_write(component, fifo->mem_offset + AIU_MEM_END,
110 				end);
111 
112 	/* Setup the fifo to read all the memory - no skip */
113 	snd_soc_component_update_bits(component,
114 				      fifo->mem_offset + AIU_MEM_MASKS,
115 				      AIU_MEM_MASK_CH_RD | AIU_MEM_MASK_CH_MEM,
116 				      FIELD_PREP(AIU_MEM_MASK_CH_RD, 0xff) |
117 				      FIELD_PREP(AIU_MEM_MASK_CH_MEM, 0xff));
118 
119 	return 0;
120 }
121 
122 static irqreturn_t aiu_fifo_isr(int irq, void *dev_id)
123 {
124 	struct snd_pcm_substream *playback = dev_id;
125 
126 	snd_pcm_period_elapsed(playback);
127 
128 	return IRQ_HANDLED;
129 }
130 
131 int aiu_fifo_startup(struct snd_pcm_substream *substream,
132 		     struct snd_soc_dai *dai)
133 {
134 	struct aiu_fifo *fifo = dai->playback_dma_data;
135 	int ret;
136 
137 	snd_soc_set_runtime_hwparams(substream, fifo->pcm);
138 
139 	/*
140 	 * Make sure the buffer and period size are multiple of the fifo burst
141 	 * size
142 	 */
143 	ret = snd_pcm_hw_constraint_step(substream->runtime, 0,
144 					 SNDRV_PCM_HW_PARAM_BUFFER_BYTES,
145 					 fifo->fifo_block);
146 	if (ret)
147 		return ret;
148 
149 	ret = snd_pcm_hw_constraint_step(substream->runtime, 0,
150 					 SNDRV_PCM_HW_PARAM_PERIOD_BYTES,
151 					 fifo->fifo_block);
152 	if (ret)
153 		return ret;
154 
155 	ret = clk_prepare_enable(fifo->pclk);
156 	if (ret)
157 		return ret;
158 
159 	ret = request_irq(fifo->irq, aiu_fifo_isr, 0, dev_name(dai->dev),
160 			  substream);
161 	if (ret)
162 		clk_disable_unprepare(fifo->pclk);
163 
164 	return ret;
165 }
166 
167 void aiu_fifo_shutdown(struct snd_pcm_substream *substream,
168 		       struct snd_soc_dai *dai)
169 {
170 	struct aiu_fifo *fifo = dai->playback_dma_data;
171 
172 	free_irq(fifo->irq, substream);
173 	clk_disable_unprepare(fifo->pclk);
174 }
175 
176 int aiu_fifo_pcm_new(struct snd_soc_pcm_runtime *rtd,
177 		     struct snd_soc_dai *dai)
178 {
179 	struct snd_card *card = rtd->card->snd_card;
180 	struct aiu_fifo *fifo = dai->playback_dma_data;
181 	size_t size = fifo->pcm->buffer_bytes_max;
182 
183 	snd_pcm_set_managed_buffer_all(rtd->pcm, SNDRV_DMA_TYPE_DEV,
184 				       card->dev, size, size);
185 
186 	return 0;
187 }
188 
189 int aiu_fifo_dai_probe(struct snd_soc_dai *dai)
190 {
191 	struct aiu_fifo *fifo;
192 
193 	fifo = kzalloc(sizeof(*fifo), GFP_KERNEL);
194 	if (!fifo)
195 		return -ENOMEM;
196 
197 	dai->playback_dma_data = fifo;
198 
199 	return 0;
200 }
201 
202 int aiu_fifo_dai_remove(struct snd_soc_dai *dai)
203 {
204 	kfree(dai->playback_dma_data);
205 
206 	return 0;
207 }
208 
209