2 * Copyright (C) 2012-2013, Analog Devices Inc.
3 * Author: Lars-Peter Clausen <lars@metafoo.de>
5 * Licensed under the GPL-2.
8 #include <linux/init.h>
9 #include <linux/kernel.h>
10 #include <linux/module.h>
11 #include <linux/platform_device.h>
12 #include <linux/slab.h>
14 #include <linux/clk.h>
15 #include <linux/regmap.h>
17 #include <sound/core.h>
18 #include <sound/pcm.h>
19 #include <sound/pcm_params.h>
20 #include <sound/soc.h>
21 #include <sound/initval.h>
22 #include <sound/dmaengine_pcm.h>
24 #define AXI_SPDIF_REG_CTRL 0x0
25 #define AXI_SPDIF_REG_STAT 0x4
26 #define AXI_SPDIF_REG_TX_FIFO 0xc
28 #define AXI_SPDIF_CTRL_TXDATA BIT(1)
29 #define AXI_SPDIF_CTRL_TXEN BIT(0)
30 #define AXI_SPDIF_CTRL_CLKDIV_OFFSET 8
31 #define AXI_SPDIF_CTRL_CLKDIV_MASK (0xff << 8)
33 #define AXI_SPDIF_FREQ_44100 (0x0 << 6)
34 #define AXI_SPDIF_FREQ_48000 (0x1 << 6)
35 #define AXI_SPDIF_FREQ_32000 (0x2 << 6)
36 #define AXI_SPDIF_FREQ_NA (0x3 << 6)
39 struct regmap *regmap;
43 struct snd_dmaengine_dai_dma_data dma_data;
45 struct snd_ratnum ratnum;
46 struct snd_pcm_hw_constraint_ratnums rate_constraints;
49 static int axi_spdif_trigger(struct snd_pcm_substream *substream, int cmd,
50 struct snd_soc_dai *dai)
52 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
56 case SNDRV_PCM_TRIGGER_START:
57 case SNDRV_PCM_TRIGGER_RESUME:
58 case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
59 val = AXI_SPDIF_CTRL_TXDATA;
61 case SNDRV_PCM_TRIGGER_STOP:
62 case SNDRV_PCM_TRIGGER_SUSPEND:
63 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
70 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,
71 AXI_SPDIF_CTRL_TXDATA, val);
76 static int axi_spdif_hw_params(struct snd_pcm_substream *substream,
77 struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
79 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
80 unsigned int rate = params_rate(params);
81 unsigned int clkdiv, stat;
83 switch (params_rate(params)) {
85 stat = AXI_SPDIF_FREQ_32000;
88 stat = AXI_SPDIF_FREQ_44100;
91 stat = AXI_SPDIF_FREQ_48000;
94 stat = AXI_SPDIF_FREQ_NA;
98 clkdiv = DIV_ROUND_CLOSEST(clk_get_rate(spdif->clk_ref),
100 clkdiv <<= AXI_SPDIF_CTRL_CLKDIV_OFFSET;
102 regmap_write(spdif->regmap, AXI_SPDIF_REG_STAT, stat);
103 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,
104 AXI_SPDIF_CTRL_CLKDIV_MASK, clkdiv);
109 static int axi_spdif_dai_probe(struct snd_soc_dai *dai)
111 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
113 snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);
118 static int axi_spdif_startup(struct snd_pcm_substream *substream,
119 struct snd_soc_dai *dai)
121 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
124 ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0,
125 SNDRV_PCM_HW_PARAM_RATE,
126 &spdif->rate_constraints);
130 ret = clk_prepare_enable(spdif->clk_ref);
134 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,
135 AXI_SPDIF_CTRL_TXEN, AXI_SPDIF_CTRL_TXEN);
140 static void axi_spdif_shutdown(struct snd_pcm_substream *substream,
141 struct snd_soc_dai *dai)
143 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);
145 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,
146 AXI_SPDIF_CTRL_TXEN, 0);
148 clk_disable_unprepare(spdif->clk_ref);
151 static const struct snd_soc_dai_ops axi_spdif_dai_ops = {
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 = {
159 .probe = axi_spdif_dai_probe,
163 .rates = SNDRV_PCM_RATE_KNOT,
164 .formats = SNDRV_PCM_FMTBIT_S16_LE,
166 .ops = &axi_spdif_dai_ops,
169 static const struct snd_soc_component_driver axi_spdif_component = {
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 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
194 base = devm_ioremap_resource(&pdev->dev, res);
196 return PTR_ERR(base);
198 spdif->regmap = devm_regmap_init_mmio(&pdev->dev, base,
199 &axi_spdif_regmap_config);
200 if (IS_ERR(spdif->regmap))
201 return PTR_ERR(spdif->regmap);
203 spdif->clk = devm_clk_get(&pdev->dev, "axi");
204 if (IS_ERR(spdif->clk))
205 return PTR_ERR(spdif->clk);
207 spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");
208 if (IS_ERR(spdif->clk_ref))
209 return PTR_ERR(spdif->clk_ref);
211 ret = clk_prepare_enable(spdif->clk);
215 spdif->dma_data.addr = res->start + AXI_SPDIF_REG_TX_FIFO;
216 spdif->dma_data.addr_width = 4;
217 spdif->dma_data.maxburst = 1;
219 spdif->ratnum.num = clk_get_rate(spdif->clk_ref) / 128;
220 spdif->ratnum.den_step = 1;
221 spdif->ratnum.den_min = 1;
222 spdif->ratnum.den_max = 64;
224 spdif->rate_constraints.rats = &spdif->ratnum;
225 spdif->rate_constraints.nrats = 1;
227 ret = devm_snd_soc_register_component(&pdev->dev, &axi_spdif_component,
230 goto err_clk_disable;
232 ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL,
233 SND_DMAENGINE_PCM_FLAG_NO_RESIDUE);
235 goto err_clk_disable;
240 clk_disable_unprepare(spdif->clk);
244 static int axi_spdif_dev_remove(struct platform_device *pdev)
246 struct axi_spdif *spdif = platform_get_drvdata(pdev);
248 clk_disable_unprepare(spdif->clk);
253 static const struct of_device_id axi_spdif_of_match[] = {
254 { .compatible = "adi,axi-spdif-tx-1.00.a", },
257 MODULE_DEVICE_TABLE(of, axi_spdif_of_match);
259 static struct platform_driver axi_spdif_driver = {
262 .owner = THIS_MODULE,
263 .of_match_table = axi_spdif_of_match,
265 .probe = axi_spdif_probe,
266 .remove = axi_spdif_dev_remove,
268 module_platform_driver(axi_spdif_driver);
270 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
271 MODULE_DESCRIPTION("AXI SPDIF driver");
272 MODULE_LICENSE("GPL");