2 * smdk_spdif.c -- S/PDIF audio for SMDK
4 * Copyright 2010 Samsung Electronics Co. Ltd.
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.
13 #include <linux/clk.h>
15 #include <sound/soc.h>
19 /* Audio clock settings are belonged to board specific part. Every
20 * board can set audio source clock setting which is matched with H/W
21 * like this function-'set_audio_clock_heirachy'.
23 static int set_audio_clock_heirachy(struct platform_device *pdev)
25 struct clk *fout_epll, *mout_epll, *sclk_audio0, *sclk_spdif;
28 fout_epll = clk_get(NULL, "fout_epll");
29 if (IS_ERR(fout_epll)) {
30 printk(KERN_WARNING "%s: Cannot find fout_epll.\n",
35 mout_epll = clk_get(NULL, "mout_epll");
36 if (IS_ERR(mout_epll)) {
37 printk(KERN_WARNING "%s: Cannot find mout_epll.\n",
43 sclk_audio0 = clk_get(&pdev->dev, "sclk_audio");
44 if (IS_ERR(sclk_audio0)) {
45 printk(KERN_WARNING "%s: Cannot find sclk_audio.\n",
51 sclk_spdif = clk_get(NULL, "sclk_spdif");
52 if (IS_ERR(sclk_spdif)) {
53 printk(KERN_WARNING "%s: Cannot find sclk_spdif.\n",
59 /* Set audio clock hierarchy for S/PDIF */
60 clk_set_parent(mout_epll, fout_epll);
61 clk_set_parent(sclk_audio0, mout_epll);
62 clk_set_parent(sclk_spdif, sclk_audio0);
75 /* We should haved to set clock directly on this part because of clock
76 * scheme of Samsudng SoCs did not support to set rates from abstrct
77 * clock of it's hierarchy.
79 static int set_audio_clock_rate(unsigned long epll_rate,
80 unsigned long audio_rate)
82 struct clk *fout_epll, *sclk_spdif;
84 fout_epll = clk_get(NULL, "fout_epll");
85 if (IS_ERR(fout_epll)) {
86 printk(KERN_ERR "%s: failed to get fout_epll\n", __func__);
90 clk_set_rate(fout_epll, epll_rate);
93 sclk_spdif = clk_get(NULL, "sclk_spdif");
94 if (IS_ERR(sclk_spdif)) {
95 printk(KERN_ERR "%s: failed to get sclk_spdif\n", __func__);
99 clk_set_rate(sclk_spdif, audio_rate);
105 static int smdk_hw_params(struct snd_pcm_substream *substream,
106 struct snd_pcm_hw_params *params)
108 struct snd_soc_pcm_runtime *rtd = substream->private_data;
109 struct snd_soc_dai *cpu_dai = rtd->cpu_dai;
110 unsigned long pll_out, rclk_rate;
113 switch (params_rate(params)) {
126 /* Setting ratio to 512fs helps to use S/PDIF with HDMI without
127 * modify S/PDIF ASoC machine driver.
130 rclk_rate = params_rate(params) * ratio;
132 /* Set audio source clock rates */
133 ret = set_audio_clock_rate(pll_out, rclk_rate);
137 /* Set S/PDIF uses internal source clock */
138 ret = snd_soc_dai_set_sysclk(cpu_dai, SND_SOC_SPDIF_INT_MCLK,
139 rclk_rate, SND_SOC_CLOCK_IN);
146 static struct snd_soc_ops smdk_spdif_ops = {
147 .hw_params = smdk_hw_params,
150 static struct snd_soc_dai_link smdk_dai = {
152 .stream_name = "S/PDIF PCM Playback",
153 .platform_name = "samsung-audio",
154 .cpu_dai_name = "samsung-spdif",
155 .codec_dai_name = "dit-hifi",
156 .codec_name = "spdif-dit",
157 .ops = &smdk_spdif_ops,
160 static struct snd_soc_card smdk = {
161 .name = "SMDK-S/PDIF",
162 .dai_link = &smdk_dai,
166 static struct platform_device *smdk_snd_spdif_dit_device;
167 static struct platform_device *smdk_snd_spdif_device;
169 static int __init smdk_init(void)
173 smdk_snd_spdif_dit_device = platform_device_alloc("spdif-dit", -1);
174 if (!smdk_snd_spdif_dit_device)
177 ret = platform_device_add(smdk_snd_spdif_dit_device);
181 smdk_snd_spdif_device = platform_device_alloc("soc-audio", -1);
182 if (!smdk_snd_spdif_device) {
187 platform_set_drvdata(smdk_snd_spdif_device, &smdk);
189 ret = platform_device_add(smdk_snd_spdif_device);
193 /* Set audio clock hierarchy manually */
194 ret = set_audio_clock_heirachy(smdk_snd_spdif_device);
200 platform_device_del(smdk_snd_spdif_device);
202 platform_device_put(smdk_snd_spdif_device);
204 platform_device_del(smdk_snd_spdif_dit_device);
206 platform_device_put(smdk_snd_spdif_dit_device);
210 static void __exit smdk_exit(void)
212 platform_device_unregister(smdk_snd_spdif_device);
213 platform_device_unregister(smdk_snd_spdif_dit_device);
216 module_init(smdk_init);
217 module_exit(smdk_exit);
219 MODULE_AUTHOR("Seungwhan Youn, <sw.youn@samsung.com>");
220 MODULE_DESCRIPTION("ALSA SoC SMDK+S/PDIF");
221 MODULE_LICENSE("GPL");