sound/soc/samsung/smdk_spdif.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 //
   3 // smdk_spdif.c - S/PDIF audio for SMDK
   4 //
   5 // Copyright (C) 2010 Samsung Electronics Co., Ltd.
   6
   7 #include <linux/clk.h>
   8 #include <linux/module.h>
   9
  10 #include <sound/soc.h>
  11
  12 #include "spdif.h"
  13
  14 /* Audio clock settings are belonged to board specific part. Every
  15  * board can set audio source clock setting which is matched with H/W
  16  * like this function-'set_audio_clock_heirachy'.
  17  */
  18 static int set_audio_clock_heirachy(struct platform_device *pdev)
  19 {
  20         struct clk *fout_epll, *mout_epll, *sclk_audio0, *sclk_spdif;
  21         int ret = 0;
  22
  23         fout_epll = clk_get(NULL, "fout_epll");
  24         if (IS_ERR(fout_epll)) {
  25                 printk(KERN_WARNING "%s: Cannot find fout_epll.\n",
  26                                 __func__);
  27                 return -EINVAL;
  28         }
  29
  30         mout_epll = clk_get(NULL, "mout_epll");
  31         if (IS_ERR(mout_epll)) {
  32                 printk(KERN_WARNING "%s: Cannot find mout_epll.\n",
  33                                 __func__);
  34                 ret = -EINVAL;
  35                 goto out1;
  36         }
  37
  38         sclk_audio0 = clk_get(&pdev->dev, "sclk_audio");
  39         if (IS_ERR(sclk_audio0)) {
  40                 printk(KERN_WARNING "%s: Cannot find sclk_audio.\n",
  41                                 __func__);
  42                 ret = -EINVAL;
  43                 goto out2;
  44         }
  45
  46         sclk_spdif = clk_get(NULL, "sclk_spdif");
  47         if (IS_ERR(sclk_spdif)) {
  48                 printk(KERN_WARNING "%s: Cannot find sclk_spdif.\n",
  49                                 __func__);
  50                 ret = -EINVAL;
  51                 goto out3;
  52         }
  53
  54         /* Set audio clock hierarchy for S/PDIF */
  55         clk_set_parent(mout_epll, fout_epll);
  56         clk_set_parent(sclk_audio0, mout_epll);
  57         clk_set_parent(sclk_spdif, sclk_audio0);
  58
  59         clk_put(sclk_spdif);
  60 out3:
  61         clk_put(sclk_audio0);
  62 out2:
  63         clk_put(mout_epll);
  64 out1:
  65         clk_put(fout_epll);
  66
  67         return ret;
  68 }
  69
  70 /* We should haved to set clock directly on this part because of clock
  71  * scheme of Samsudng SoCs did not support to set rates from abstrct
  72  * clock of it's hierarchy.
  73  */
  74 static int set_audio_clock_rate(unsigned long epll_rate,
  75                                 unsigned long audio_rate)
  76 {
  77         struct clk *fout_epll, *sclk_spdif;
  78
  79         fout_epll = clk_get(NULL, "fout_epll");
  80         if (IS_ERR(fout_epll)) {
  81                 printk(KERN_ERR "%s: failed to get fout_epll\n", __func__);
  82                 return -ENOENT;
  83         }
  84
  85         clk_set_rate(fout_epll, epll_rate);
  86         clk_put(fout_epll);
  87
  88         sclk_spdif = clk_get(NULL, "sclk_spdif");
  89         if (IS_ERR(sclk_spdif)) {
  90                 printk(KERN_ERR "%s: failed to get sclk_spdif\n", __func__);
  91                 return -ENOENT;
  92         }
  93
  94         clk_set_rate(sclk_spdif, audio_rate);
  95         clk_put(sclk_spdif);
  96
  97         return 0;
  98 }
  99
 100 static int smdk_hw_params(struct snd_pcm_substream *substream,
 101                 struct snd_pcm_hw_params *params)
 102 {
 103         struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
 104         struct snd_soc_dai *cpu_dai = asoc_rtd_to_cpu(rtd, 0);
 105         unsigned long pll_out, rclk_rate;
 106         int ret, ratio;
 107
 108         switch (params_rate(params)) {
 109         case 44100:
 110                 pll_out = 45158400;
 111                 break;
 112         case 32000:
 113         case 48000:
 114         case 96000:
 115                 pll_out = 49152000;
 116                 break;
 117         default:
 118                 return -EINVAL;
 119         }
 120
 121         /* Setting ratio to 512fs helps to use S/PDIF with HDMI without
 122          * modify S/PDIF ASoC machine driver.
 123          */
 124         ratio = 512;
 125         rclk_rate = params_rate(params) * ratio;
 126
 127         /* Set audio source clock rates */
 128         ret = set_audio_clock_rate(pll_out, rclk_rate);
 129         if (ret < 0)
 130                 return ret;
 131
 132         /* Set S/PDIF uses internal source clock */
 133         ret = snd_soc_dai_set_sysclk(cpu_dai, SND_SOC_SPDIF_INT_MCLK,
 134                                         rclk_rate, SND_SOC_CLOCK_IN);
 135         if (ret < 0)
 136                 return ret;
 137
 138         return ret;
 139 }
 140
 141 static const struct snd_soc_ops smdk_spdif_ops = {
 142         .hw_params = smdk_hw_params,
 143 };
 144
 145 SND_SOC_DAILINK_DEFS(spdif,
 146         DAILINK_COMP_ARRAY(COMP_CPU("samsung-spdif")),
 147         DAILINK_COMP_ARRAY(COMP_CODEC("spdif-dit", "dit-hifi")),
 148         DAILINK_COMP_ARRAY(COMP_PLATFORM("samsung-spdif")));
 149
 150 static struct snd_soc_dai_link smdk_dai = {
 151         .name = "S/PDIF",
 152         .stream_name = "S/PDIF PCM Playback",
 153         .ops = &smdk_spdif_ops,
 154         SND_SOC_DAILINK_REG(spdif),
 155 };
 156
 157 static struct snd_soc_card smdk = {
 158         .name = "SMDK-S/PDIF",
 159         .owner = THIS_MODULE,
 160         .dai_link = &smdk_dai,
 161         .num_links = 1,
 162 };
 163
 164 static struct platform_device *smdk_snd_spdif_dit_device;
 165 static struct platform_device *smdk_snd_spdif_device;
 166
 167 static int __init smdk_init(void)
 168 {
 169         int ret;
 170
 171         smdk_snd_spdif_dit_device = platform_device_alloc("spdif-dit", -1);
 172         if (!smdk_snd_spdif_dit_device)
 173                 return -ENOMEM;
 174
 175         ret = platform_device_add(smdk_snd_spdif_dit_device);
 176         if (ret)
 177                 goto err1;
 178
 179         smdk_snd_spdif_device = platform_device_alloc("soc-audio", -1);
 180         if (!smdk_snd_spdif_device) {
 181                 ret = -ENOMEM;
 182                 goto err2;
 183         }
 184
 185         platform_set_drvdata(smdk_snd_spdif_device, &smdk);
 186
 187         ret = platform_device_add(smdk_snd_spdif_device);
 188         if (ret)
 189                 goto err3;
 190
 191         /* Set audio clock hierarchy manually */
 192         ret = set_audio_clock_heirachy(smdk_snd_spdif_device);
 193         if (ret)
 194                 goto err4;
 195
 196         return 0;
 197 err4:
 198         platform_device_del(smdk_snd_spdif_device);
 199 err3:
 200         platform_device_put(smdk_snd_spdif_device);
 201 err2:
 202         platform_device_del(smdk_snd_spdif_dit_device);
 203 err1:
 204         platform_device_put(smdk_snd_spdif_dit_device);
 205         return ret;
 206 }
 207
 208 static void __exit smdk_exit(void)
 209 {
 210         platform_device_unregister(smdk_snd_spdif_device);
 211         platform_device_unregister(smdk_snd_spdif_dit_device);
 212 }
 213
 214 module_init(smdk_init);
 215 module_exit(smdk_exit);
 216
 217 MODULE_AUTHOR("Seungwhan Youn, <sw.youn@samsung.com>");
 218 MODULE_DESCRIPTION("ALSA SoC SMDK+S/PDIF");
 219 MODULE_LICENSE("GPL");