radio-cadet.c

trident tm5600的linux驱动

/* radio-cadet.c - A video4linux driver for the ADS Cadet AM/FM Radio Card
 *
 * by Fred Gleason <[e-mail]>
 * Version 0.3.3
 *
 * (Loosely) based on code for the Aztech radio card by
 *
 * Russell Kroll    ([e-mail])
 * Quay Ly
 * Donald Song
 * Jason Lewis      ([e-mail])
 * Scott McGrath    ([e-mail])
 * William McGrath  ([e-mail])
 *
 * History:
 * 2000-04-29	Russell Kroll <[e-mail]>
 *		Added ISAPnP detection for Linux 2.3/2.4
 *
 * 2001-01-10	Russell Kroll <[e-mail]>
 *		Removed dead CONFIG_RADIO_CADET_PORT code
 *		PnP detection on load is now default (no args necessary)
 *
 * 2002-01-17	Adam Belay <[e-mail]>
 *		Updated to latest pnp code
 *
 * 2003-01-31	Alan Cox <[e-mail]>
 *		Cleaned up locking, delay code, general odds and ends
 *
 * 2006-07-30	Hans J. Koch <[e-mail]>
 *		Changed API to V4L2
 */

#include <linux/version.h>
#include <linux/module.h>	/* Modules 			*/
#include <linux/init.h>		/* Initdata			*/
#include <linux/ioport.h>	/* request_region		*/
#include <linux/delay.h>	/* udelay			*/
#include <asm/io.h>		/* outb, outb_p			*/
#include <asm/uaccess.h>	/* copy to/from user		*/
#include "compat.h"
#include <linux/videodev2.h>	/* V4L2 API defs		*/
#include <media/v4l2-common.h>
#include <media/v4l2-ioctl.h>
#include <linux/param.h>
#include <linux/pnp.h>

#define RDS_BUFFER 256
#define RDS_RX_FLAG 1
#define MBS_RX_FLAG 2

#define CADET_VERSION KERNEL_VERSION(0,3,3)

static struct v4l2_queryctrl radio_qctrl[] = {
	{
		.id            = V4L2_CID_AUDIO_MUTE,
		.name          = "Mute",
		.minimum       = 0,
		.maximum       = 1,
		.default_value = 1,
		.type          = V4L2_CTRL_TYPE_BOOLEAN,
	},{
		.id            = V4L2_CID_AUDIO_VOLUME,
		.name          = "Volume",
		.minimum       = 0,
		.maximum       = 0xff,
		.step          = 1,
		.default_value = 0xff,
		.type          = V4L2_CTRL_TYPE_INTEGER,
	}
};

static int io=-1;		/* default to isapnp activation */
static int radio_nr = -1;
static int users;
static int curtuner;
static int tunestat;
static int sigstrength;
static wait_queue_head_t read_queue;
static struct timer_list readtimer;
static __u8 rdsin, rdsout, rdsstat;
static unsigned char rdsbuf[RDS_BUFFER];
static spinlock_t cadet_io_lock;

static int cadet_probe(void);

/*
 * Signal Strength Threshold Values
 * The V4L API spec does not define any particular unit for the signal
 * strength value.  These values are in microvolts of RF at the tuner's input.
 */
static __u16 sigtable[2][4]={{5,10,30,150},{28,40,63,1000}};

#if 0
/*
Note: cadet_getrds() is not used at the moment. It will be useful for future
extensions, e.g. an ioctl to query RDS reception quality. - Hans J. Koch
*/
static int
cadet_getrds(void)
{
	int rds_mbs_stat=0;

	spin_lock(&cadet_io_lock);
	outb(3,io);                 /* Select Decoder Control/Status */
	outb(inb(io+1)&0x7f,io+1);  /* Reset RDS detection */
	spin_unlock(&cadet_io_lock);

	msleep(100);

	spin_lock(&cadet_io_lock);
	outb(3,io);                 /* Select Decoder Control/Status */
	if((inb(io+1)&0x80)!=0) {
		rds_mbs_stat |= RDS_RX_FLAG;
	}
	if((inb(io+1)&0x10)!=0) {
		rds_mbs_stat |= MBS_RX_FLAG;
	}
	spin_unlock(&cadet_io_lock);
	return rds_mbs_stat;
}
#endif

static int
cadet_getstereo(void)
{
	int ret = V4L2_TUNER_SUB_MONO;
	if(curtuner != 0)	/* Only FM has stereo capability! */
		return V4L2_TUNER_SUB_MONO;

	spin_lock(&cadet_io_lock);
	outb(7,io);          /* Select tuner control */
	if( (inb(io+1) & 0x40) == 0)
		ret = V4L2_TUNER_SUB_STEREO;
	spin_unlock(&cadet_io_lock);
	return ret;
}

static unsigned
cadet_gettune(void)
{
	int curvol,i;
	unsigned fifo=0;

	/*
	 * Prepare for read
	 */

	spin_lock(&cadet_io_lock);

	outb(7,io);       /* Select tuner control */
	curvol=inb(io+1); /* Save current volume/mute setting */
	outb(0x00,io+1);  /* Ensure WRITE-ENABLE is LOW */
	tunestat=0xffff;

	/*
	 * Read the shift register
	 */
	for(i=0;i<25;i++) {
		fifo=(fifo<<1)|((inb(io+1)>>7)&0x01);
		if(i<24) {
			outb(0x01,io+1);
			tunestat&=inb(io+1);
			outb(0x00,io+1);
		}
	}

	/*
	 * Restore volume/mute setting
	 */
	outb(curvol,io+1);
	spin_unlock(&cadet_io_lock);

	return fifo;
}

static unsigned
cadet_getfreq(void)
{
	int i;
	unsigned freq=0,test,fifo=0;

	/*
	 * Read current tuning
	 */
	fifo=cadet_gettune();

	/*
	 * Convert to actual frequency
	 */
	if(curtuner==0) {    /* FM */
		test=12500;
		for(i=0;i<14;i++) {
			if((fifo&0x01)!=0) {
				freq+=test;
			}
			test=test<<1;
			fifo=fifo>>1;
		}
		freq-=10700000;           /* IF frequency is 10.7 MHz */
		freq=(freq*16)/1000000;   /* Make it 1/16 MHz */
	}
	if(curtuner==1) {    /* AM */
		freq=((fifo&0x7fff)-2010)*16;
	}

	return freq;
}

static void
cadet_settune(unsigned fifo)
{
	int i;
	unsigned test;

	spin_lock(&cadet_io_lock);

	outb(7,io);                /* Select tuner control */
	/*
	 * Write the shift register
	 */
	test=0;
	test=(fifo>>23)&0x02;      /* Align data for SDO */
	test|=0x1c;                /* SDM=1, SWE=1, SEN=1, SCK=0 */
	outb(7,io);                /* Select tuner control */
	outb(test,io+1);           /* Initialize for write */
	for(i=0;i<25;i++) {
		test|=0x01;              /* Toggle SCK High */
		outb(test,io+1);
		test&=0xfe;              /* Toggle SCK Low */
		outb(test,io+1);
		fifo=fifo<<1;            /* Prepare the next bit */
		test=0x1c|((fifo>>23)&0x02);
		outb(test,io+1);
	}
	spin_unlock(&cadet_io_lock);
}

static void
cadet_setfreq(unsigned freq)
{
	unsigned fifo;
	int i,j,test;
	int curvol;

	/*
	 * Formulate a fifo command
	 */
	fifo=0;
	if(curtuner==0) {    /* FM */
		test=102400;
		freq=(freq*1000)/16;       /* Make it kHz */
		freq+=10700;               /* IF is 10700 kHz */
		for(i=0;i<14;i++) {
			fifo=fifo<<1;
			if(freq>=test) {
				fifo|=0x01;
				freq-=test;
			}
			test=test>>1;
		}
	}
	if(curtuner==1) {    /* AM */
		fifo=(freq/16)+2010;            /* Make it kHz */
		fifo|=0x100000;            /* Select AM Band */
	}

	/*
	 * Save current volume/mute setting
	 */

	spin_lock(&cadet_io_lock);
	outb(7,io);                /* Select tuner control */
	curvol=inb(io+1);
	spin_unlock(&cadet_io_lock);

	/*
	 * Tune the card
	 */
	for(j=3;j>-1;j--) {
		cadet_settune(fifo|(j<<16));

		spin_lock(&cadet_io_lock);
		outb(7,io);         /* Select tuner control */
		outb(curvol,io+1);
		spin_unlock(&cadet_io_lock);

		msleep(100);

		cadet_gettune();
		if((tunestat & 0x40) == 0) {   /* Tuned */
			sigstrength=sigtable[curtuner][j];
			return;
		}
	}
	sigstrength=0;
}


static int
cadet_getvol(void)
{
	int ret = 0;

	spin_lock(&cadet_io_lock);

	outb(7,io);                /* Select tuner control */
	if((inb(io + 1) & 0x20) != 0)
		ret = 0xffff;

	spin_unlock(&cadet_io_lock);
	return ret;
}


static void
cadet_setvol(int vol)
{
	spin_lock(&cadet_io_lock);
	outb(7,io);                /* Select tuner control */
	if(vol>0)
		outb(0x20,io+1);
	else
		outb(0x00,io+1);
	spin_unlock(&cadet_io_lock);
}

static void
cadet_handler(unsigned long data)
{
	/*
	 * Service the RDS fifo
	 */

	if(spin_trylock(&cadet_io_lock))
	{
		outb(0x3,io);       /* Select RDS Decoder Control */
		if((inb(io+1)&0x20)!=0) {
			printk(KERN_CRIT "cadet: RDS fifo overflow\n");
		}
		outb(0x80,io);      /* Select RDS fifo */
		while((inb(io)&0x80)!=0) {
			rdsbuf[rdsin]=inb(io+1);
			if(rdsin==rdsout)
				printk(KERN_WARNING "cadet: RDS buffer overflow\n");
			else
				rdsin++;
		}
		spin_unlock(&cadet_io_lock);
	}

	/*
	 * Service pending read
	 */
	if( rdsin!=rdsout)
		wake_up_interruptible(&read_queue);

	/*
	 * Clean up and exit
	 */
	init_timer(&readtimer);
	readtimer.function=cadet_handler;
	readtimer.data=(unsigned long)0;
	readtimer.expires=jiffies+msecs_to_jiffies(50);
	add_timer(&readtimer);
}



static ssize_t
cadet_read(struct file *file, char __user *data, size_t count, loff_t *ppos)
{
	int i=0;
	unsigned char readbuf[RDS_BUFFER];