[ALSA] hda-intel - Add hwdep interface

Added a hwdep interface for each codec (enabled per kconfig).
This interface can be used for reading/writing HD-audio verbs
and other purposes as future extensions.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

1 files changed, 122 insertions, 0 deletions

diff --git a/sound/pci/hda/hda_hwdep.c b/sound/pci/hda/hda_hwdep.c
new file mode 100644
index 00000000000..64be7b53348
--- /dev/null
+++ b/sound/pci/hda/hda_hwdep.c
@@ -0,0 +1,122 @@
+/*
+ * HWDEP Interface for HD-audio codec
+ *
+ * Copyright (c) 2007 Takashi Iwai <tiwai@suse.de>
+ *
+ *  This driver 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.
+ *
+ *  This driver is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <sound/driver.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <linux/compat.h>
+#include <linux/mutex.h>
+#include <sound/core.h>
+#include "hda_codec.h"
+#include "hda_local.h"
+#include <sound/hda_hwdep.h>
+
+/*
+ * write/read an out-of-bound verb
+ */
+static int verb_write_ioctl(struct hda_codec *codec,
+			    struct hda_verb_ioctl __user *arg)
+{
+	u32 verb, res;
+
+	if (get_user(verb, &arg->verb))
+		return -EFAULT;
+	res = snd_hda_codec_read(codec, verb >> 24, 0,
+				 (verb >> 8) & 0xffff, verb & 0xff);
+	if (put_user(res, &arg->res))
+		return -EFAULT;
+	return 0;
+}
+
+static int get_wcap_ioctl(struct hda_codec *codec,
+			  struct hda_verb_ioctl __user *arg)
+{
+	u32 verb, res;
+	
+	if (get_user(verb, &arg->verb))
+		return -EFAULT;
+	res = get_wcaps(codec, verb >> 24);
+	if (put_user(res, &arg->res))
+		return -EFAULT;
+	return 0;
+}
+
+
+/*
+ */
+static int hda_hwdep_ioctl(struct snd_hwdep *hw, struct file *file,
+			   unsigned int cmd, unsigned long arg)
+{
+	struct hda_codec *codec = hw->private_data;
+	void __user *argp = (void __user *)arg;
+
+	switch (cmd) {
+	case HDA_IOCTL_PVERSION:
+		return put_user(HDA_HWDEP_VERSION, (int __user *)argp);
+	case HDA_IOCTL_VERB_WRITE:
+		return verb_write_ioctl(codec, argp);
+	case HDA_IOCTL_GET_WCAP:
+		return get_wcap_ioctl(codec, argp);
+	}
+	return -ENOIOCTLCMD;
+}
+
+#ifdef CONFIG_COMPAT
+static int hda_hwdep_ioctl_compat(struct snd_hwdep *hw, struct file *file,
+				  unsigned int cmd, unsigned long arg)
+{
+	return hda_hwdep_ioctl(hw, file, cmd, compat_ptr(arg));
+}
+#endif
+
+static int hda_hwdep_open(struct snd_hwdep *hw, struct file *file)
+{
+#ifndef CONFIG_SND_DEBUG_DETECT
+	if (!capable(CAP_SYS_RAWIO))
+		return -EACCES;
+#endif
+	return 0;
+}
+
+int __devinit snd_hda_create_hwdep(struct hda_codec *codec)
+{
+	char hwname[16];
+	struct snd_hwdep *hwdep;
+	int err;
+
+	sprintf(hwname, "HDA Codec %d", codec->addr);
+	err = snd_hwdep_new(codec->bus->card, hwname, codec->addr, &hwdep);
+	if (err < 0)
+		return err;
+	codec->hwdep = hwdep;
+	sprintf(hwdep->name, "HDA Codec %d", codec->addr);
+	hwdep->iface = SNDRV_HWDEP_IFACE_HDA;
+	hwdep->private_data = codec;
+	hwdep->exclusive = 1;
+
+	hwdep->ops.open = hda_hwdep_open;
+	hwdep->ops.ioctl = hda_hwdep_ioctl;
+#ifdef CONFIG_COMPAT
+	hwdep->ops.ioctl_compat = hda_hwdep_ioctl_compat;
+#endif
+
+	return 0;
+}