/* Miro PCM20 radio driver for Linux radio support
 * (c) 1998 Ruurd Reitsma <R.A.Reitsma@wbmt.tudelft.nl>
 * Thanks to Norberto Pellici for the ACI device interface specification
 * The API part is based on the radiotrack driver by M. Kirkwood
 * This driver relies on the aci mixer (drivers/sound/aci.c)
 * Look there for further info...
 */

/* Revision history:
 *
 *   1998        Ruurd Reitsma <R.A.Reitsma@wbmt.tudelft.nl>
 *   2000-09-05  Robert Siemer <Robert.Siemer@gmx.de>
 *        removed unfinished volume control (maybe adding it later again)
 *        use OSS-mixer; added stereo control
 */

/* What ever you think about the ACI, version 0x07 is not very well!
 * I cant get frequency, 'tuner status', 'tuner flags' or mute/mono
 * conditions...                Robert 
 */

#include <linux/module.h>
#include <linux/init.h>
#include <linux/videodev.h>
#include <linux/devfs_fs_kernel.h>
#include <asm/uaccess.h>

char * aci_radio_name;

#include "../../sound/aci.h"

static int users = 0;

struct pcm20_device
{
	unsigned long freq;
	int muted;
	int stereo;
};


static int pcm20_mute(struct pcm20_device *dev, unsigned char mute)
{
	dev->muted = mute;
	return aci_write_cmd(0xa3, mute);
}

static int pcm20_stereo(struct pcm20_device *dev, unsigned char stereo)
{
	dev->stereo = stereo;
	return aci_write_cmd(0xa4, !stereo);
}

static int pcm20_setfreq(struct pcm20_device *dev, unsigned long freq)
{
	unsigned char freql;
	unsigned char freqh;

	dev->freq=freq;

	freq /= 160;
	if (!(aci_version==0x07 || aci_version>=0xb0))
		freq /= 10;  /* I don't know exactly which version
			      * needs this hack */
	freql = freq & 0xff;
	freqh = freq >> 8;

	aci_rds_cmd(RDS_RESET, 0, 0);
	pcm20_stereo(dev, 1);

	return aci_rw_cmd(0xa7, freql, freqh);	/*  Tune to frequency	*/
}

static int pcm20_getflags(struct pcm20_device *dev, __u32 *flags, __u16 *signal)
{
	/* okay, check for signal, stereo and rds here... */
	int i;
	unsigned char buf;

	if ((i=aci_rw_cmd(0xa9, -1, -1))<0)
		return i;
#if DEBUG
	printk("check_sig: 0x%x\n", i);
#endif
	if (i & 0x80) {
		/* no signal from tuner */
		*flags=0;
		*signal=0;
		return 0;
	} else
		*signal=0xffff;

	if ((i=aci_rw_cmd(0xa8, -1, -1))<0)
		return i;
	if (i & 0x40) {
		*flags=0;
	} else {
		/* stereo */
		*flags=VIDEO_TUNER_STEREO_ON;
		/* I cant see stereo, when forced to mono */
		dev->stereo=1;
	}

	if ((i=aci_rds_cmd(RDS_STATUS, &buf, 1))<0)
		return i;
	if (buf & 1)
		/* RDS available */
		*flags|=VIDEO_TUNER_RDS_ON;
	else
		return 0;

	if ((i=aci_rds_cmd(RDS_RXVALUE, &buf, 1))<0)
		return i;
#if DEBUG
	printk("rds-signal: %d\n", buf);
#endif
	if (buf > 15) {
		printk("rds-miropcm20: RX strengths unexpected high...\n");
		buf=15;
	}
	/* refine signal */
	if ((*signal=SCALE(15, 0xffff, buf))==0)
		*signal = 1;

	return 0;
}

static int pcm20_ioctl(struct video_device *dev, unsigned int cmd, void *arg)
{
	struct pcm20_device *pcm20=dev->priv;
	int i;
	
	switch(cmd)
	{
		case VIDIOCGCAP:
		{
			struct video_capability v;
			v.type=VID_TYPE_TUNER;
			strcpy(v.name, "Miro PCM20");
			v.channels=1;
			v.audios=1;
			/* No we don't do pictures */
			v.maxwidth=0;
			v.maxheight=0;
			v.minwidth=0;
			v.minheight=0;
			if(copy_to_user(arg,&v,sizeof(v)))
				return -EFAULT;
			return 0;
		}
		case VIDIOCGTUNER:
		{
			struct video_tuner v;
			if(copy_from_user(&v, arg,sizeof(v))!=0) 
				return -EFAULT;
			if(v.tuner)	/* Only 1 tuner */ 
				return -EINVAL;
			v.rangelow=87*16000;
			v.rangehigh=108*16000;
			pcm20_getflags(pcm20, &v.flags, &v.signal);
			v.flags|=VIDEO_TUNER_LOW;
			v.mode=VIDEO_MODE_AUTO;
			strcpy(v.name, "FM");
			if(copy_to_user(arg,&v, sizeof(v)))
				return -EFAULT;
			return 0;
		}
		case VIDIOCSTUNER:
		{
			struct video_tuner v;
			if(copy_from_user(&v, arg, sizeof(v)))
				return -EFAULT;
			if(v.tuner!=0)
				return -EINVAL;
			/* Only 1 tuner so no setting needed ! */
			return 0;
		}
		case VIDIOCGFREQ:
			if(copy_to_user(arg, &pcm20->freq, sizeof(pcm20->freq)))
				return -EFAULT;
			return 0;
		case VIDIOCSFREQ:
			if(copy_from_user(&pcm20->freq, arg, sizeof(pcm20->freq)))
				return -EFAULT;
			i=pcm20_setfreq(pcm20, pcm20->freq);
#if DEBUG
			printk("First view (setfreq): 0x%x\n", i);
#endif
			return i;
		case VIDIOCGAUDIO:
		{	
			struct video_audio v;
			memset(&v,0, sizeof(v));
			v.flags=VIDEO_AUDIO_MUTABLE;
			if (pcm20->muted)
				v.flags|=VIDEO_AUDIO_MUTE;
			v.mode=VIDEO_SOUND_STEREO;
			if (pcm20->stereo)
				v.mode|=VIDEO_SOUND_MONO;
			/* v.step=2048; */
			strcpy(v.name, "Radio");
			if(copy_to_user(arg,&v, sizeof(v)))
				return -EFAULT;
			return 0;			
		}
		case VIDIOCSAUDIO:
		{
			struct video_audio v;
			if(copy_from_user(&v, arg, sizeof(v))) 
				return -EFAULT;
			if(v.audio) 
				return -EINVAL;

			pcm20_mute(pcm20, !!(v.flags&VIDEO_AUDIO_MUTE));
			if(v.flags&VIDEO_SOUND_MONO)
				pcm20_stereo(pcm20, 0);
			if(v.flags&VIDEO_SOUND_STEREO)
				pcm20_stereo(pcm20, 1);

			return 0;
		}
		default:
			return -ENOIOCTLCMD;
	}
}

static int pcm20_open(struct video_device *dev, int flags)
{
	if(users)
		return -EBUSY;
	users++;
	return 0;
}

static void pcm20_close(struct video_device *dev)
{
	users--;
}

static struct pcm20_device pcm20_unit=
{
	freq:   87*16000,
	muted:  1,
	stereo: 0
};

static struct video_device pcm20_radio=
{
	owner:		THIS_MODULE,
	name:		"Miro PCM 20 radio",
	type:		VID_TYPE_TUNER,
	hardware:	VID_HARDWARE_RTRACK,
	open:		pcm20_open,
	close:		pcm20_close,
	ioctl:		pcm20_ioctl,
	priv:		&pcm20_unit
};

static int __init pcm20_init(void)
{
	if(video_register_device(&pcm20_radio, VFL_TYPE_RADIO)==-1)
		return -EINVAL;
		
	if(attach_aci_rds()<0) {
		video_unregister_device(&pcm20_radio);
		return -EINVAL;
	}
#if DEBUG
	printk("v4l-name: %s\n", devfs_get_name(pcm20_radio.devfs_handle, 0));
#endif
	printk(KERN_INFO "Miro PCM20 radio card driver.\n");

	return 0;
}

MODULE_AUTHOR("Ruurd Reitsma");
MODULE_DESCRIPTION("A driver for the Miro PCM20 radio card.");

EXPORT_NO_SYMBOLS;

static void __exit pcm20_cleanup(void)
{
	unload_aci_rds();
	video_unregister_device(&pcm20_radio);
}

module_init(pcm20_init);
module_exit(pcm20_cleanup);
