268 lines · c
1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2012-2013, Analog Devices Inc.4 * Author: Lars-Peter Clausen <lars@metafoo.de>5 */6 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>12#include <linux/of.h>13#include <linux/clk.h>14#include <linux/regmap.h>15 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>22 23#define AXI_SPDIF_REG_CTRL 0x024#define AXI_SPDIF_REG_STAT 0x425#define AXI_SPDIF_REG_TX_FIFO 0xc26 27#define AXI_SPDIF_CTRL_TXDATA BIT(1)28#define AXI_SPDIF_CTRL_TXEN BIT(0)29#define AXI_SPDIF_CTRL_CLKDIV_OFFSET 830#define AXI_SPDIF_CTRL_CLKDIV_MASK (0xff << 8)31 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)36 37struct axi_spdif {38 struct regmap *regmap;39 struct clk *clk;40 struct clk *clk_ref;41 42 struct snd_dmaengine_dai_dma_data dma_data;43 44 struct snd_ratnum ratnum;45 struct snd_pcm_hw_constraint_ratnums rate_constraints;46};47 48static int axi_spdif_trigger(struct snd_pcm_substream *substream, int cmd,49 struct snd_soc_dai *dai)50{51 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);52 unsigned int val;53 54 switch (cmd) {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;59 break;60 case SNDRV_PCM_TRIGGER_STOP:61 case SNDRV_PCM_TRIGGER_SUSPEND:62 case SNDRV_PCM_TRIGGER_PAUSE_PUSH:63 val = 0;64 break;65 default:66 return -EINVAL;67 }68 69 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,70 AXI_SPDIF_CTRL_TXDATA, val);71 72 return 0;73}74 75static int axi_spdif_hw_params(struct snd_pcm_substream *substream,76 struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)77{78 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);79 unsigned int rate = params_rate(params);80 unsigned int clkdiv, stat;81 82 switch (params_rate(params)) {83 case 32000:84 stat = AXI_SPDIF_FREQ_32000;85 break;86 case 44100:87 stat = AXI_SPDIF_FREQ_44100;88 break;89 case 48000:90 stat = AXI_SPDIF_FREQ_48000;91 break;92 default:93 stat = AXI_SPDIF_FREQ_NA;94 break;95 }96 97 clkdiv = DIV_ROUND_CLOSEST(clk_get_rate(spdif->clk_ref),98 rate * 64 * 2) - 1;99 clkdiv <<= AXI_SPDIF_CTRL_CLKDIV_OFFSET;100 101 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);104 105 return 0;106}107 108static int axi_spdif_dai_probe(struct snd_soc_dai *dai)109{110 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);111 112 snd_soc_dai_init_dma_data(dai, &spdif->dma_data, NULL);113 114 return 0;115}116 117static int axi_spdif_startup(struct snd_pcm_substream *substream,118 struct snd_soc_dai *dai)119{120 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);121 int ret;122 123 ret = snd_pcm_hw_constraint_ratnums(substream->runtime, 0,124 SNDRV_PCM_HW_PARAM_RATE,125 &spdif->rate_constraints);126 if (ret)127 return ret;128 129 ret = clk_prepare_enable(spdif->clk_ref);130 if (ret)131 return ret;132 133 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,134 AXI_SPDIF_CTRL_TXEN, AXI_SPDIF_CTRL_TXEN);135 136 return 0;137}138 139static void axi_spdif_shutdown(struct snd_pcm_substream *substream,140 struct snd_soc_dai *dai)141{142 struct axi_spdif *spdif = snd_soc_dai_get_drvdata(dai);143 144 regmap_update_bits(spdif->regmap, AXI_SPDIF_REG_CTRL,145 AXI_SPDIF_CTRL_TXEN, 0);146 147 clk_disable_unprepare(spdif->clk_ref);148}149 150static 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,156};157 158static struct snd_soc_dai_driver axi_spdif_dai = {159 .playback = {160 .channels_min = 2,161 .channels_max = 2,162 .rates = SNDRV_PCM_RATE_KNOT,163 .formats = SNDRV_PCM_FMTBIT_S16_LE,164 },165 .ops = &axi_spdif_dai_ops,166};167 168static const struct snd_soc_component_driver axi_spdif_component = {169 .name = "axi-spdif",170 .legacy_dai_naming = 1,171};172 173static const struct regmap_config axi_spdif_regmap_config = {174 .reg_bits = 32,175 .reg_stride = 4,176 .val_bits = 32,177 .max_register = AXI_SPDIF_REG_STAT,178};179 180static int axi_spdif_probe(struct platform_device *pdev)181{182 struct axi_spdif *spdif;183 struct resource *res;184 void __iomem *base;185 int ret;186 187 spdif = devm_kzalloc(&pdev->dev, sizeof(*spdif), GFP_KERNEL);188 if (!spdif)189 return -ENOMEM;190 191 platform_set_drvdata(pdev, spdif);192 193 base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);194 if (IS_ERR(base))195 return PTR_ERR(base);196 197 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);201 202 spdif->clk = devm_clk_get(&pdev->dev, "axi");203 if (IS_ERR(spdif->clk))204 return PTR_ERR(spdif->clk);205 206 spdif->clk_ref = devm_clk_get(&pdev->dev, "ref");207 if (IS_ERR(spdif->clk_ref))208 return PTR_ERR(spdif->clk_ref);209 210 ret = clk_prepare_enable(spdif->clk);211 if (ret)212 return ret;213 214 spdif->dma_data.addr = res->start + AXI_SPDIF_REG_TX_FIFO;215 spdif->dma_data.addr_width = 4;216 spdif->dma_data.maxburst = 1;217 218 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;222 223 spdif->rate_constraints.rats = &spdif->ratnum;224 spdif->rate_constraints.nrats = 1;225 226 ret = devm_snd_soc_register_component(&pdev->dev, &axi_spdif_component,227 &axi_spdif_dai, 1);228 if (ret)229 goto err_clk_disable;230 231 ret = devm_snd_dmaengine_pcm_register(&pdev->dev, NULL, 0);232 if (ret)233 goto err_clk_disable;234 235 return 0;236 237err_clk_disable:238 clk_disable_unprepare(spdif->clk);239 return ret;240}241 242static void axi_spdif_dev_remove(struct platform_device *pdev)243{244 struct axi_spdif *spdif = platform_get_drvdata(pdev);245 246 clk_disable_unprepare(spdif->clk);247}248 249static const struct of_device_id axi_spdif_of_match[] = {250 { .compatible = "adi,axi-spdif-tx-1.00.a", },251 {},252};253MODULE_DEVICE_TABLE(of, axi_spdif_of_match);254 255static struct platform_driver axi_spdif_driver = {256 .driver = {257 .name = "axi-spdif",258 .of_match_table = axi_spdif_of_match,259 },260 .probe = axi_spdif_probe,261 .remove = axi_spdif_dev_remove,262};263module_platform_driver(axi_spdif_driver);264 265MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");266MODULE_DESCRIPTION("AXI SPDIF driver");267MODULE_LICENSE("GPL");268