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 = substream->private_data; 104 struct snd_soc_dai *cpu_dai = rtd->cpu_dai; 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 static struct snd_soc_dai_link smdk_dai = { 146 .name = "S/PDIF", 147 .stream_name = "S/PDIF PCM Playback", 148 .platform_name = "samsung-spdif", 149 .cpu_dai_name = "samsung-spdif", 150 .codec_dai_name = "dit-hifi", 151 .codec_name = "spdif-dit", 152 .ops = &smdk_spdif_ops, 153 }; 154 155 static struct snd_soc_card smdk = { 156 .name = "SMDK-S/PDIF", 157 .owner = THIS_MODULE, 158 .dai_link = &smdk_dai, 159 .num_links = 1, 160 }; 161 162 static struct platform_device *smdk_snd_spdif_dit_device; 163 static struct platform_device *smdk_snd_spdif_device; 164 165 static int __init smdk_init(void) 166 { 167 int ret; 168 169 smdk_snd_spdif_dit_device = platform_device_alloc("spdif-dit", -1); 170 if (!smdk_snd_spdif_dit_device) 171 return -ENOMEM; 172 173 ret = platform_device_add(smdk_snd_spdif_dit_device); 174 if (ret) 175 goto err1; 176 177 smdk_snd_spdif_device = platform_device_alloc("soc-audio", -1); 178 if (!smdk_snd_spdif_device) { 179 ret = -ENOMEM; 180 goto err2; 181 } 182 183 platform_set_drvdata(smdk_snd_spdif_device, &smdk); 184 185 ret = platform_device_add(smdk_snd_spdif_device); 186 if (ret) 187 goto err3; 188 189 /* Set audio clock hierarchy manually */ 190 ret = set_audio_clock_heirachy(smdk_snd_spdif_device); 191 if (ret) 192 goto err4; 193 194 return 0; 195 err4: 196 platform_device_del(smdk_snd_spdif_device); 197 err3: 198 platform_device_put(smdk_snd_spdif_device); 199 err2: 200 platform_device_del(smdk_snd_spdif_dit_device); 201 err1: 202 platform_device_put(smdk_snd_spdif_dit_device); 203 return ret; 204 } 205 206 static void __exit smdk_exit(void) 207 { 208 platform_device_unregister(smdk_snd_spdif_device); 209 platform_device_unregister(smdk_snd_spdif_dit_device); 210 } 211 212 module_init(smdk_init); 213 module_exit(smdk_exit); 214 215 MODULE_AUTHOR("Seungwhan Youn, <sw.youn@samsung.com>"); 216 MODULE_DESCRIPTION("ALSA SoC SMDK+S/PDIF"); 217 MODULE_LICENSE("GPL"); 218