1 /* 2 * smdk_spdif.c -- S/PDIF audio for SMDK 3 * 4 * Copyright 2010 Samsung Electronics Co. Ltd. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License as 8 * published by the Free Software Foundation; either version 2 of the 9 * License, or (at your option) any later version. 10 * 11 */ 12 13 #include <linux/module.h> 14 #include <linux/device.h> 15 #include <linux/clk.h> 16 17 #include <plat/devs.h> 18 19 #include <sound/soc.h> 20 21 #include "dma.h" 22 #include "spdif.h" 23 24 /* Audio clock settings are belonged to board specific part. Every 25 * board can set audio source clock setting which is matched with H/W 26 * like this function-'set_audio_clock_heirachy'. 27 */ 28 static int set_audio_clock_heirachy(struct platform_device *pdev) 29 { 30 struct clk *fout_epll, *mout_epll, *sclk_audio0, *sclk_spdif; 31 int ret = 0; 32 33 fout_epll = clk_get(NULL, "fout_epll"); 34 if (IS_ERR(fout_epll)) { 35 printk(KERN_WARNING "%s: Cannot find fout_epll.\n", 36 __func__); 37 return -EINVAL; 38 } 39 40 mout_epll = clk_get(NULL, "mout_epll"); 41 if (IS_ERR(mout_epll)) { 42 printk(KERN_WARNING "%s: Cannot find mout_epll.\n", 43 __func__); 44 ret = -EINVAL; 45 goto out1; 46 } 47 48 sclk_audio0 = clk_get(&pdev->dev, "sclk_audio"); 49 if (IS_ERR(sclk_audio0)) { 50 printk(KERN_WARNING "%s: Cannot find sclk_audio.\n", 51 __func__); 52 ret = -EINVAL; 53 goto out2; 54 } 55 56 sclk_spdif = clk_get(NULL, "sclk_spdif"); 57 if (IS_ERR(sclk_spdif)) { 58 printk(KERN_WARNING "%s: Cannot find sclk_spdif.\n", 59 __func__); 60 ret = -EINVAL; 61 goto out3; 62 } 63 64 /* Set audio clock hierarchy for S/PDIF */ 65 clk_set_parent(mout_epll, fout_epll); 66 clk_set_parent(sclk_audio0, mout_epll); 67 clk_set_parent(sclk_spdif, sclk_audio0); 68 69 clk_put(sclk_spdif); 70 out3: 71 clk_put(sclk_audio0); 72 out2: 73 clk_put(mout_epll); 74 out1: 75 clk_put(fout_epll); 76 77 return ret; 78 } 79 80 /* We should haved to set clock directly on this part because of clock 81 * scheme of Samsudng SoCs did not support to set rates from abstrct 82 * clock of it's hierarchy. 83 */ 84 static int set_audio_clock_rate(unsigned long epll_rate, 85 unsigned long audio_rate) 86 { 87 struct clk *fout_epll, *sclk_spdif; 88 89 fout_epll = clk_get(NULL, "fout_epll"); 90 if (IS_ERR(fout_epll)) { 91 printk(KERN_ERR "%s: failed to get fout_epll\n", __func__); 92 return -ENOENT; 93 } 94 95 clk_set_rate(fout_epll, epll_rate); 96 clk_put(fout_epll); 97 98 sclk_spdif = clk_get(NULL, "sclk_spdif"); 99 if (IS_ERR(sclk_spdif)) { 100 printk(KERN_ERR "%s: failed to get sclk_spdif\n", __func__); 101 return -ENOENT; 102 } 103 104 clk_set_rate(sclk_spdif, audio_rate); 105 clk_put(sclk_spdif); 106 107 return 0; 108 } 109 110 static int smdk_hw_params(struct snd_pcm_substream *substream, 111 struct snd_pcm_hw_params *params) 112 { 113 struct snd_soc_pcm_runtime *rtd = substream->private_data; 114 struct snd_soc_dai *cpu_dai = rtd->cpu_dai; 115 unsigned long pll_out, rclk_rate; 116 int ret, ratio; 117 118 switch (params_rate(params)) { 119 case 44100: 120 pll_out = 45158400; 121 break; 122 case 32000: 123 case 48000: 124 case 96000: 125 pll_out = 49152000; 126 break; 127 default: 128 return -EINVAL; 129 } 130 131 /* Setting ratio to 512fs helps to use S/PDIF with HDMI without 132 * modify S/PDIF ASoC machine driver. 133 */ 134 ratio = 512; 135 rclk_rate = params_rate(params) * ratio; 136 137 /* Set audio source clock rates */ 138 ret = set_audio_clock_rate(pll_out, rclk_rate); 139 if (ret < 0) 140 return ret; 141 142 /* Set S/PDIF uses internal source clock */ 143 ret = snd_soc_dai_set_sysclk(cpu_dai, SND_SOC_SPDIF_INT_MCLK, 144 rclk_rate, SND_SOC_CLOCK_IN); 145 if (ret < 0) 146 return ret; 147 148 return ret; 149 } 150 151 static struct snd_soc_ops smdk_spdif_ops = { 152 .hw_params = smdk_hw_params, 153 }; 154 155 static struct snd_soc_dai_link smdk_dai = { 156 .name = "S/PDIF", 157 .stream_name = "S/PDIF PCM Playback", 158 .platform_name = "samsung-audio", 159 .cpu_dai_name = "samsung-spdif", 160 .codec_dai_name = "dit-hifi", 161 .codec_name = "spdif-dit", 162 .ops = &smdk_spdif_ops, 163 }; 164 165 static struct snd_soc_card smdk = { 166 .name = "SMDK-S/PDIF", 167 .dai_link = &smdk_dai, 168 .num_links = 1, 169 }; 170 171 static struct platform_device *smdk_snd_spdif_dit_device; 172 static struct platform_device *smdk_snd_spdif_device; 173 174 static int __init smdk_init(void) 175 { 176 int ret; 177 178 smdk_snd_spdif_dit_device = platform_device_alloc("spdif-dit", -1); 179 if (!smdk_snd_spdif_dit_device) 180 return -ENOMEM; 181 182 ret = platform_device_add(smdk_snd_spdif_dit_device); 183 if (ret) 184 goto err1; 185 186 smdk_snd_spdif_device = platform_device_alloc("soc-audio", -1); 187 if (!smdk_snd_spdif_device) { 188 ret = -ENOMEM; 189 goto err2; 190 } 191 192 platform_set_drvdata(smdk_snd_spdif_device, &smdk); 193 194 ret = platform_device_add(smdk_snd_spdif_device); 195 if (ret) 196 goto err3; 197 198 /* Set audio clock hierarchy manually */ 199 ret = set_audio_clock_heirachy(smdk_snd_spdif_device); 200 if (ret) 201 goto err4; 202 203 return 0; 204 err4: 205 platform_device_del(smdk_snd_spdif_device); 206 err3: 207 platform_device_put(smdk_snd_spdif_device); 208 err2: 209 platform_device_del(smdk_snd_spdif_dit_device); 210 err1: 211 platform_device_put(smdk_snd_spdif_dit_device); 212 return ret; 213 } 214 215 static void __exit smdk_exit(void) 216 { 217 platform_device_unregister(smdk_snd_spdif_device); 218 platform_device_unregister(smdk_snd_spdif_dit_device); 219 } 220 221 module_init(smdk_init); 222 module_exit(smdk_exit); 223 224 MODULE_AUTHOR("Seungwhan Youn, <sw.youn@samsung.com>"); 225 MODULE_DESCRIPTION("ALSA SoC SMDK+S/PDIF"); 226 MODULE_LICENSE("GPL"); 227