[ALSA] ASoC codecs: generic AC97 support

This patch allows the std Alsa AC97 codec driver to use any AsoC AC97
controller driver. Currently, only HiFi playback and Capture are
supported atm.

Signed-off-by: Richard Purdie <rpurdie@rpsys.net>
Signed-off-by: Liam Girdwood <liam.girdwood@wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

2 files changed, 185 insertions, 0 deletions

diff --git a/sound/soc/codecs/ac97.c b/sound/soc/codecs/ac97.c
new file mode 100644
index 000000000000..dd1a9f579a6b
--- /dev/null
+++ b/sound/soc/codecs/ac97.c
@@ -0,0 +1,167 @@
+/*
+ * ac97.c  --  ALSA Soc AC97 codec support
+ *
+ * Copyright 2005 Wolfson Microelectronics PLC.
+ * Author: Liam Girdwood
+ *         liam.girdwood@wolfsonmicro.com or linux@wolfsonmicro.com
+ *
+ *  This program is free software; you can redistribute  it and/or modify it
+ *  under  the terms of  the GNU General  Public License as published by the
+ *  Free Software Foundation;  either version 2 of the  License, or (at your
+ *  option) any later version.
+ *
+ *  Revision history
+ *    17th Oct 2005   Initial version.
+ *
+ * Generic AC97 support.
+ */
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <sound/driver.h>
+#include <sound/core.h>
+#include <sound/pcm.h>
+#include <sound/ac97_codec.h>
+#include <sound/initval.h>
+#include <sound/soc.h>
+
+#define AC97_VERSION "0.5"
+
+#define AC97_DIR \
+        (SND_SOC_DAIDIR_PLAYBACK | SND_SOC_DAIDIR_CAPTURE)
+
+#define AC97_RATES \
+        (SNDRV_PCM_RATE_8000 | SNDRV_PCM_RATE_11025 | SNDRV_PCM_RATE_16000 | \
+        SNDRV_PCM_RATE_22050 | SNDRV_PCM_RATE_32000 | SNDRV_PCM_RATE_44100 | \
+        SNDRV_PCM_RATE_48000)
+
+/* may need to expand this */
+static struct snd_soc_dai_mode soc_ac97[] = {
+        {0, 0,  SNDRV_PCM_FMTBIT_S16_LE,        AC97_RATES},
+        {0, 0,  SNDRV_PCM_FMTBIT_S18_3LE,       AC97_RATES},
+        {0, 0,  SNDRV_PCM_FMTBIT_S20_3LE,       AC97_RATES},
+};
+
+static int ac97_prepare(struct snd_pcm_substream *substream)
+{
+        struct snd_pcm_runtime *runtime = substream->runtime;
+        struct snd_soc_pcm_runtime *rtd = substream->private_data;
+        struct snd_soc_device *socdev = rtd->socdev;
+        struct snd_soc_codec *codec = socdev->codec;
+
+        int reg = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) ?
+                  AC97_PCM_FRONT_DAC_RATE : AC97_PCM_LR_ADC_RATE;
+        return snd_ac97_set_rate(codec->ac97, reg, runtime->rate);
+}
+
+static struct snd_soc_codec_dai ac97_dai = {
+        .name = "AC97 HiFi",
+        .playback = {
+                .stream_name = "AC97 Playback",
+                .channels_min = 1,
+                .channels_max = 2,},
+        .capture = {
+                .stream_name = "AC97 Capture",
+                .channels_min = 1,
+                .channels_max = 2,},
+        .ops = {
+                .prepare = ac97_prepare,},
+        .caps = {
+                .num_modes = ARRAY_SIZE(soc_ac97),
+                .mode = soc_ac97,},
+};
+
+static unsigned int ac97_read(struct snd_soc_codec *codec,
+        unsigned int reg)
+{
+        return soc_ac97_ops.read(codec->ac97, reg);
+}
+
+static int ac97_write(struct snd_soc_codec *codec, unsigned int reg,
+        unsigned int val)
+{
+        soc_ac97_ops.write(codec->ac97, reg, val);
+        return 0;
+}
+
+static int ac97_soc_probe(struct platform_device *pdev)
+{
+        struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+        struct snd_soc_codec *codec;
+        struct snd_ac97_bus *ac97_bus;
+        struct snd_ac97_template ac97_template;
+        int ret = 0;
+
+        printk(KERN_INFO "AC97 SoC Audio Codec %s\n", AC97_VERSION);
+
+        socdev->codec = kzalloc(sizeof(struct snd_soc_codec), GFP_KERNEL);
+        if (socdev->codec == NULL)
+                return -ENOMEM;
+        codec = socdev->codec;
+        mutex_init(&codec->mutex);
+
+        codec->name = "AC97";
+        codec->owner = THIS_MODULE;
+        codec->dai = &ac97_dai;
+        codec->num_dai = 1;
+        codec->write = ac97_write;
+        codec->read = ac97_read;
+        INIT_LIST_HEAD(&codec->dapm_widgets);
+        INIT_LIST_HEAD(&codec->dapm_paths);
+
+        /* register pcms */
+        ret = snd_soc_new_pcms(socdev, SNDRV_DEFAULT_IDX1, SNDRV_DEFAULT_STR1);
+        if(ret < 0)
+                goto err;
+
+        /* add codec as bus device for standard ac97 */
+        ret = snd_ac97_bus(codec->card, 0, &soc_ac97_ops, NULL, &ac97_bus);
+        if(ret < 0)
+                goto bus_err;
+
+        memset(&ac97_template, 0, sizeof(struct snd_ac97_template));
+        ret = snd_ac97_mixer(ac97_bus, &ac97_template, &codec->ac97);
+        if(ret < 0)
+                goto bus_err;
+
+        ret = snd_soc_register_card(socdev);
+        if (ret < 0)
+                goto bus_err;
+        return 0;
+
+bus_err:
+        snd_soc_free_pcms(socdev);
+
+err:
+        kfree(socdev->codec->reg_cache);
+        kfree(socdev->codec);
+        socdev->codec = NULL;
+        return ret;
+}
+
+static int ac97_soc_remove(struct platform_device *pdev)
+{
+        struct snd_soc_device *socdev = platform_get_drvdata(pdev);
+        struct snd_soc_codec *codec = socdev->codec;
+
+        if(codec == NULL)
+                return 0;
+
+        snd_soc_free_pcms(socdev);
+        kfree(socdev->codec->reg_cache);
+        kfree(socdev->codec);
+
+        return 0;
+}
+
+struct snd_soc_codec_device soc_codec_dev_ac97= {
+        .probe =        ac97_soc_probe,
+        .remove =       ac97_soc_remove,
+};
+
+EXPORT_SYMBOL_GPL(soc_codec_dev_ac97);
+
+MODULE_DESCRIPTION("Soc Generic AC97 driver");
+MODULE_AUTHOR("Liam Girdwood");
+MODULE_LICENSE("GPL");
diff --git a/sound/soc/codecs/ac97.h b/sound/soc/codecs/ac97.h
new file mode 100644
index 000000000000..930ddfc2321a
--- /dev/null
+++ b/sound/soc/codecs/ac97.h
@@ -0,0 +1,18 @@
+/*
+ * linux/sound/codecs/ac97.h -- ALSA SoC Layer
+ *
+ * Author:              Liam Girdwood
+ * Created:             Dec 1st 2005
+ * Copyright:   Wolfson Microelectronics. PLC.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#ifndef __LINUX_SND_SOC_AC97_H
+#define __LINUX_SND_SOC_AC97_H
+
+extern struct snd_soc_codec_device soc_codec_dev_ac97;
+
+#endif