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/module.h>
14 #include <linux/device.h>
15 #include <linux/clk.h>
17 #include <plat/devs.h>
19 #include <sound/soc.h>
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'.
28 static int set_audio_clock_heirachy(struct platform_device *pdev)
30 struct clk *fout_epll, *mout_epll, *sclk_audio0, *sclk_spdif;
33 fout_epll = clk_get(NULL, "fout_epll");
34 if (IS_ERR(fout_epll)) {
35 printk(KERN_WARNING "%s: Cannot find fout_epll.\n",
40 mout_epll = clk_get(NULL, "mout_epll");
41 if (IS_ERR(fout_epll)) {
42 printk(KERN_WARNING "%s: Cannot find mout_epll.\n",
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",
56 sclk_spdif = clk_get(NULL, "sclk_spdif");
57 if (IS_ERR(fout_epll)) {
58 printk(KERN_WARNING "%s: Cannot find sclk_spdif.\n",
64 /* Set audio clock heirachy 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);
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 heirachy.
84 static int set_audio_clock_rate(unsigned long epll_rate,
85 unsigned long audio_rate)
87 struct clk *fout_epll, *sclk_spdif;
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__);
95 clk_set_rate(fout_epll, epll_rate);
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__);
104 clk_set_rate(sclk_spdif, audio_rate);
110 static int smdk_hw_params(struct snd_pcm_substream *substream,
111 struct snd_pcm_hw_params *params)
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;
118 switch (params_rate(params)) {
131 /* Setting ratio to 512fs helps to use S/PDIF with HDMI without
132 * modify S/PDIF ASoC machine driver.
135 rclk_rate = params_rate(params) * ratio;
137 /* Set audio source clock rates */
138 ret = set_audio_clock_rate(pll_out, rclk_rate);
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);
151 static struct snd_soc_ops smdk_spdif_ops = {
152 .hw_params = smdk_hw_params,
155 static struct snd_soc_card smdk;
157 static struct snd_soc_dai_link smdk_dai = {
159 .stream_name = "S/PDIF PCM Playback",
160 .platform_name = "s3c24xx-pcm-audio",
161 .cpu_dai_name = "samsung-spdif",
162 .codec_dai_name = "dit-hifi",
163 .codec_name = "spdif-dit",
164 .ops = &smdk_spdif_ops,
167 static struct snd_soc_card smdk = {
168 .name = "SMDK-S/PDIF",
169 .dai_link = &smdk_dai,
173 static struct platform_device *smdk_snd_spdif_dit_device;
174 static struct platform_device *smdk_snd_spdif_device;
176 static int __init smdk_init(void)
180 smdk_snd_spdif_dit_device = platform_device_alloc("spdif-dit", -1);
181 if (!smdk_snd_spdif_dit_device)
184 ret = platform_device_add(smdk_snd_spdif_dit_device);
188 smdk_snd_spdif_device = platform_device_alloc("soc-audio", -1);
189 if (!smdk_snd_spdif_device) {
194 platform_set_drvdata(smdk_snd_spdif_device, &smdk);
196 ret = platform_device_add(smdk_snd_spdif_device);
200 /* Set audio clock heirachy manually */
201 ret = set_audio_clock_heirachy(smdk_snd_spdif_device);
207 platform_device_put(smdk_snd_spdif_device);
209 platform_device_put(smdk_snd_spdif_dit_device);
213 static void __exit smdk_exit(void)
215 platform_device_unregister(smdk_snd_spdif_device);
218 module_init(smdk_init);
219 module_exit(smdk_exit);
221 MODULE_AUTHOR("Seungwhan Youn, <sw.youn@samsung.com>");
222 MODULE_DESCRIPTION("ALSA SoC SMDK+S/PDIF");
223 MODULE_LICENSE("GPL");