1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2012-2013, Analog Devices Inc.
4 * Author: Lars-Peter Clausen <lars@metafoo.de>
7 #include <linux/init.h>
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/platform_device.h>
11 #include <linux/slab.h>
13 #include <linux/clk.h>
14 #include <linux/regmap.h>
16 #include <sound/core.h>
17 #include <sound/pcm.h>
18 #include <sound/pcm_params.h>
19 #include <sound/soc.h>
20 #include <sound/initval.h>
21 #include <sound/dmaengine_pcm.h>
23 #define AXI_SPDIF_REG_CTRL 0x0
24 #define AXI_SPDIF_REG_STAT 0x4
25 #define AXI_SPDIF_REG_TX_FIFO 0xc
27 #define AXI_SPDIF_CTRL_TXDATA BIT(1)
28 #define AXI_SPDIF_CTRL_TXEN BIT(0)
29 #define AXI_SPDIF_CTRL_CLKDIV_OFFSET 8
30 #define AXI_SPDIF_CTRL_CLKDIV_MASK (0xff << 8)
32 #define AXI_SPDIF_FREQ_44100 (0x0 << 6)
33 #define AXI_SPDIF_FREQ_48000 (0x1 << 6)
34 #define AXI_SPDIF_FREQ_32000 (0x2 << 6)
35 #define AXI_SPDIF_FREQ_NA (0x3 << 6)
38 struct regmap *regmap;
42 struct snd_dmaengine_dai_dma_data dma_data;
44 struct snd_ratnum ratnum;
45 struct snd_pcm_hw_constraint_ratnums rate_constraints;
48 static int axi_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
49 struct snd_soc_dai *dai)
51 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
55 case SNDRV_PCM_TRIGGER_START:
56 case SNDRV_PCM_TRIGGER_RESUME:
57 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
58 val = AXI_SPDIF_CTRL_TXDATA;
60 case SNDRV_PCM_TRIGGER_STOP:
61 case SNDRV_PCM_TRIGGER_SUSPEND:
62 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
69 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,
70 AXI_SPDIF_CTRL_TXDATA, val);
75 static int axi_spdif_hw_params(struct snd_pcm_substream *substream,
76 struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
78 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
79 unsigned int rate = params_rate(params);
80 unsigned int clkdiv, stat;
82 switch (params_rate(params)) {
84 stat = AXI_SPDIF_FREQ_32000;
87 stat = AXI_SPDIF_FREQ_44100;
90 stat = AXI_SPDIF_FREQ_48000;
93 stat = AXI_SPDIF_FREQ_NA;
97 clkdiv = DIV_ROUND_CLOSEST(clk_get_rate(spdif->clk_ref),
99 clkdiv <<= AXI_SPDIF_CTRL_CLKDIV_OFFSET;
101 regmap_write(spdif->regmap, AXI_SPDIF_REG_STAT, stat);
102 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,
103 AXI_SPDIF_CTRL_CLKDIV_MASK, clkdiv);
108 static int axi_spdif_dai_probe(struct snd_soc_dai *dai)
110 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
112 snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);
117 static int axi_spdif_startup(struct snd_pcm_substream *substream,
118 struct snd_soc_dai *dai)
120 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
123 ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0,
124 SNDRV_PCM_HW_PARAM_RATE,
125 &spdif->rate_constraints);
129 ret = clk_prepare_enable(spdif->clk_ref);
133 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,
134 AXI_SPDIF_CTRL_TXEN, AXI_SPDIF_CTRL_TXEN);
139 static void axi_spdif_shutdown(struct snd_pcm_substream *substream,
140 struct snd_soc_dai *dai)
142 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
144 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,
145 AXI_SPDIF_CTRL_TXEN, 0);
147 clk_disable_unprepare(spdif->clk_ref);
150 static const struct snd_soc_dai_ops axi_spdif_dai_ops = {
151 .probe = axi_spdif_dai_probe,
152 .startup = axi_spdif_startup,
153 .shutdown = axi_spdif_shutdown,
154 .trigger = axi_spdif_trigger,
155 .hw_params = axi_spdif_hw_params,
158 static struct snd_soc_dai_driver axi_spdif_dai = {
162 .rates = SNDRV_PCM_RATE_KNOT,
163 .formats = SNDRV_PCM_FMTBIT_S16_LE,
165 .ops = &axi_spdif_dai_ops,
168 static const struct snd_soc_component_driver axi_spdif_component = {
170 .legacy_dai_naming = 1,
173 static const struct regmap_config axi_spdif_regmap_config = {
177 .max_register = AXI_SPDIF_REG_STAT,
180 static int axi_spdif_probe(struct platform_device *pdev)
182 struct axi_spdif *spdif;
183 struct resource *res;
187 spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);
191 platform_set_drvdata(pdev, spdif);
193 base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
195 return PTR_ERR(base);
197 spdif->regmap = devm_regmap_init_mmio(&pdev->dev, base,
198 &axi_spdif_regmap_config);
199 if (IS_ERR(spdif->regmap))
200 return PTR_ERR(spdif->regmap);
202 spdif->clk = devm_clk_get(&pdev->dev, "axi");
203 if (IS_ERR(spdif->clk))
204 return PTR_ERR(spdif->clk);
206 spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");
207 if (IS_ERR(spdif->clk_ref))
208 return PTR_ERR(spdif->clk_ref);
210 ret = clk_prepare_enable(spdif->clk);
214 spdif->dma_data.addr = res->start + AXI_SPDIF_REG_TX_FIFO;
215 spdif->dma_data.addr_width = 4;
216 spdif->dma_data.maxburst = 1;
218 spdif->ratnum.num = clk_get_rate(spdif->clk_ref) / 128;
219 spdif->ratnum.den_step = 1;
220 spdif->ratnum.den_min = 1;
221 spdif->ratnum.den_max = 64;
223 spdif->rate_constraints.rats = &spdif->ratnum;
224 spdif->rate_constraints.nrats = 1;
226 ret = devm_snd_soc_register_component(&pdev->dev, &axi_spdif_component,
229 goto err_clk_disable;
231 ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);
233 goto err_clk_disable;
238 clk_disable_unprepare(spdif->clk);
242 static void axi_spdif_dev_remove(struct platform_device *pdev)
244 struct axi_spdif *spdif = platform_get_drvdata(pdev);
246 clk_disable_unprepare(spdif->clk);
249 static const struct of_device_id axi_spdif_of_match[] = {
250 { .compatible = "adi,axi-spdif-tx-1.00.a", },
253 MODULE_DEVICE_TABLE(of, axi_spdif_of_match);
255 static struct platform_driver axi_spdif_driver = {
258 .of_match_table = axi_spdif_of_match,
260 .probe = axi_spdif_probe,
261 .remove_new = axi_spdif_dev_remove,
263 module_platform_driver(axi_spdif_driver);
265 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
266 MODULE_DESCRIPTION("AXI SPDIF driver");
267 MODULE_LICENSE("GPL");