/*
 * This should perform the 'PCF8584 initialization sequence' as described
 * in the Philips IC12 data book (1995, Aug 29).
 * There should be a 30 clock cycle wait after reset, I assume this
 * has been fulfilled.
 * There should be a delay at the end equal to the longest I2C message
 * to synchronize the BB-bit (in multimaster systems). How long is
 * this? I assume 1 second is always long enough.
 *
 * vdovikin: added detect code for PCF8584
 */
static int pcf_init_8584 (struct i2c_algo_pcf_data *adap)
{
	unsigned char temp;

//	DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: PCF state 0x%02x\n",
;

	/* S1=0x80: S0 selected, serial interface off */
	set_pcf(adap, 1, I2C_PCF_PIN);
	/*
	 * check to see S1 now used as R/W ctrl -
	 * PCF8584 does that when ESO is zero
	 */
	if (((temp = get_pcf(adap, 1)) & 0x7f) != (0)) {
;
		return -ENXIO; /* definitely not PCF8584 */
	}

	/* load own address in S0, effective address is (own << 1) */
	i2c_outb(adap, get_own(adap));
	/* check it's really written */
	if ((temp = i2c_inb(adap)) != get_own(adap)) {
;
		return -ENXIO;
	}

	/* S1=0xA0, next byte in S2 */
	set_pcf(adap, 1, I2C_PCF_PIN | I2C_PCF_ES1);
	/* check to see S2 now selected */
	if (((temp = get_pcf(adap, 1)) & 0x7f) != I2C_PCF_ES1) {
;
		return -ENXIO;
	}

	/* load clock register S2 */
	i2c_outb(adap, get_clock(adap));
	/* check it's really written, the only 5 lowest bits does matter */
	if (((temp = i2c_inb(adap)) & 0x1f) != get_clock(adap)) {
;
		return -ENXIO;
	}

	/* Enable serial interface, idle, S0 selected */
	set_pcf(adap, 1, I2C_PCF_IDLE);

	/* check to see PCF is really idled and we can access status register */
	if ((temp = get_pcf(adap, 1)) != (I2C_PCF_PIN | I2C_PCF_BB)) {
;
		return -ENXIO;
	}

;

	return 0;
}
static int pcf_init_8584 (struct i2c_algo_pcf_data *adap)
{
	unsigned char temp;

	DEB3(printk(KERN_DEBUG "i2c-algo-pcf.o: PCF state 0x%02x\n",
				get_pcf(adap, 1)));

	/*                                            */
	set_pcf(adap, 1, I2C_PCF_PIN);
	/*
                                          
                                      
  */
	if (((temp = get_pcf(adap, 1)) & 0x7f) != (0)) {
		DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S0 (0x%02x).\n", temp));
		return -ENXIO; /*                        */
	}

	/*                                                         */
	i2c_outb(adap, get_own(adap));
	/*                           */
	if ((temp = i2c_inb(adap)) != get_own(adap)) {
		DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't set S0 (0x%02x).\n", temp));
		return -ENXIO;
	}

	/*                          */
	set_pcf(adap, 1, I2C_PCF_PIN | I2C_PCF_ES1);
	/*                              */
	if (((temp = get_pcf(adap, 1)) & 0x7f) != I2C_PCF_ES1) {
		DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S2 (0x%02x).\n", temp));
		return -ENXIO;
	}

	/*                        */
	i2c_outb(adap, get_clock(adap));
	/*                                                               */
	if (((temp = i2c_inb(adap)) & 0x1f) != get_clock(adap)) {
		DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't set S2 (0x%02x).\n", temp));
		return -ENXIO;
	}

	/*                                            */
	set_pcf(adap, 1, I2C_PCF_IDLE);

	/*                                                                    */
	if ((temp = get_pcf(adap, 1)) != (I2C_PCF_PIN | I2C_PCF_BB)) {
		DEB2(printk(KERN_ERR "i2c-algo-pcf.o: PCF detection failed -- can't select S1` (0x%02x).\n", temp));
		return -ENXIO;
	}

	printk(KERN_DEBUG "i2c-algo-pcf.o: detected and initialized PCF8584.\n");

	return 0;
}
static void handle_lab(struct i2c_algo_pcf_data *adap, const int *status)
{
	DEB2(printk(KERN_INFO
		"i2c-algo-pcf.o: lost arbitration (CSR 0x%02x)\n",
		 *status));

	/* Cleanup from LAB -- reset and enable ESO.
	 * This resets the PCF8584; since we've lost the bus, no
	 * further attempts should be made by callers to clean up
	 * (no i2c_stop() etc.)
	 */
	set_pcf(adap, 1, I2C_PCF_PIN);
	set_pcf(adap, 1, I2C_PCF_ESO);

	/* We pause for a time period sufficient for any running
	 * I2C transaction to complete -- the arbitration logic won't
	 * work properly until the next START is seen.
	 * It is assumed the bus driver or client has set a proper value.
	 *
	 * REVISIT: should probably use msleep instead of mdelay if we
	 * know we can sleep.
	 */
	if (adap->lab_mdelay)
		mdelay(adap->lab_mdelay);

	DEB2(printk(KERN_INFO
		"i2c-algo-pcf.o: reset LAB condition (CSR 0x%02x)\n",
		get_pcf(adap, 1)));
}
static void handle_lab(struct i2c_algo_pcf_data *adap, const int *status)
{
	DEB2(printk(KERN_INFO
		"i2c-algo-pcf.o: lost arbitration (CSR 0x%02x)\n",
		*status));
	/*
                                             
                                                         
                                                          
                        
  */
	set_pcf(adap, 1, I2C_PCF_PIN);
	set_pcf(adap, 1, I2C_PCF_ESO);
	/*
                                                         
                                                              
                                               
                                                                  
   
                                                               
                      
  */
	if (adap->lab_mdelay)
		mdelay(adap->lab_mdelay);

	DEB2(printk(KERN_INFO
		"i2c-algo-pcf.o: reset LAB condition (CSR 0x%02x)\n",
		get_pcf(adap, 1)));
}
static int wait_for_bb(struct i2c_algo_pcf_data *adap) {

	int timeout = DEF_TIMEOUT;
	int status;

	status = get_pcf(adap, 1);
#ifndef STUB_I2C
	while (timeout-- && !(status & I2C_PCF_BB)) {
		udelay(100); /* wait for 100 us */
		status = get_pcf(adap, 1);
	}
#endif
	if (timeout <= 0) {
		printk(KERN_ERR "Timeout waiting for Bus Busy\n");
	}
	
	return (timeout<=0);
}
static int wait_for_bb(struct i2c_algo_pcf_data *adap)
{

	int timeout = DEF_TIMEOUT;
	int status;

	status = get_pcf(adap, 1);

	while (!(status & I2C_PCF_BB) && --timeout) {
		udelay(100); /* wait for 100 us */
		status = get_pcf(adap, 1);
	}

	if (timeout == 0) {
;
		return -ETIMEDOUT;
	}

	return 0;
}
static int wait_for_pin(struct i2c_algo_pcf_data *adap, int *status) {

	int timeout = DEF_TIMEOUT;

	*status = get_pcf(adap, 1);
#ifndef STUB_I2C
	while (timeout-- && (*status & I2C_PCF_PIN)) {
		adap->waitforpin();
		*status = get_pcf(adap, 1);
	}
	if (*status & I2C_PCF_LAB) {
		handle_lab(adap, status);
		return(-EINTR);
	}
#endif
	if (timeout <= 0)
		return(-1);
	else
		return(0);
}
static int wait_for_bb(struct i2c_algo_pcf_data *adap)
{

	int timeout = DEF_TIMEOUT;
	int status;

	status = get_pcf(adap, 1);

	while (!(status & I2C_PCF_BB) && --timeout) {
		udelay(100); /*                 */
		status = get_pcf(adap, 1);
	}

	if (timeout == 0) {
		printk(KERN_ERR "Timeout waiting for Bus Busy\n");
		return -ETIMEDOUT;
	}

	return 0;
}
static int wait_for_pin(struct i2c_algo_pcf_data *adap, int *status)
{

	int timeout = DEF_TIMEOUT;

	*status = get_pcf(adap, 1);

	while ((*status & I2C_PCF_PIN) && --timeout) {
		adap->waitforpin(adap->data);
		*status = get_pcf(adap, 1);
	}
	if (*status & I2C_PCF_LAB) {
		handle_lab(adap, status);
		return -EINTR;
	}

	if (timeout == 0)
		return -ETIMEDOUT;

	return 0;
}
Beispiel #10
0
static int wait_for_pin(struct i2c_algo_pcf_data *adap, int *status) {

    int timeout = DEF_TIMEOUT;

    *status = get_pcf(adap, 1);
#ifndef STUB_I2C
    while (timeout-- && (*status & I2C_PCF_PIN)) {
        adap->waitforpin();
        *status = get_pcf(adap, 1);
    }
    if (*status & I2C_PCF_LAB) {
        DEB2(printk(KERN_INFO 
            "i2c-algo-pcf.o: lost arbitration (CSR 0x%02x)\n",
             *status));
        /* Cleanup from LAB-- reset and enable ESO.
         * This resets the PCF8584; since we've lost the bus, no
         * further attempts should be made by callers to clean up 
         * (no i2c_stop() etc.)
         */
        set_pcf(adap, 1, I2C_PCF_PIN);
        set_pcf(adap, 1, I2C_PCF_ESO);
        /* TODO: we should pause for a time period sufficient for any
         * running I2C transaction to complete-- the arbitration
         * logic won't work properly until the next START is seen.
         */
        DEB2(printk(KERN_INFO 
            "i2c-algo-pcf.o: reset LAB condition (CSR 0x%02x)\n", 
            get_pcf(adap,1)));
        return(-EINTR);
    }
#endif
    if (timeout <= 0)
        return(-1);
    else
        return(0);
}