X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fi2c%2Falgos%2Fi2c-algo-pcf.c;h=ecb2c2d7d540241745e27137f45da6b1cf52c081;hb=refs%2Fheads%2Fvserver;hp=fbbe1d2bdcc42205cba823a28e0793c2fb7120a5;hpb=6a77f38946aaee1cd85eeec6cf4229b204c15071;p=linux-2.6.git

diff --git a/drivers/i2c/algos/i2c-algo-pcf.c b/drivers/i2c/algos/i2c-algo-pcf.c
index fbbe1d2bd..ecb2c2d7d 100644
--- a/drivers/i2c/algos/i2c-algo-pcf.c
+++ b/drivers/i2c/algos/i2c-algo-pcf.c
@@ -78,7 +78,6 @@ static void i2c_stop(struct i2c_algo_pcf_data *adap)
 	set_pcf(adap, 1, I2C_PCF_STOP);
 }
 
-
 static int wait_for_bb(struct i2c_algo_pcf_data *adap) {
 
 	int timeout = DEF_TIMEOUT;
@@ -109,6 +108,26 @@ static int wait_for_pin(struct i2c_algo_pcf_data *adap, int *status) {
 		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);
@@ -188,16 +207,22 @@ static inline int try_address(struct i2c_algo_pcf_data *adap,
 		       unsigned char addr, int retries)
 {
 	int i, status, ret = -1;
+	int wfp;
 	for (i=0;i<retries;i++) {
 		i2c_outb(adap, addr);
 		i2c_start(adap);
 		status = get_pcf(adap, 1);
-		if (wait_for_pin(adap, &status) >= 0) {
+		if ((wfp = wait_for_pin(adap, &status)) >= 0) {
 			if ((status & I2C_PCF_LRB) == 0) { 
 				i2c_stop(adap);
 				break;	/* success! */
 			}
 		}
+		if (wfp == -EINTR) {
+			/* arbitration lost */
+			udelay(adap->udelay);
+			return -EINTR;
+		}
 		i2c_stop(adap);
 		udelay(adap->udelay);
 	}
@@ -219,6 +244,10 @@ static int pcf_sendbytes(struct i2c_adapter *i2c_adap, const char *buf,
 		i2c_outb(adap, buf[wrcount]);
 		timeout = wait_for_pin(adap, &status);
 		if (timeout) {
+			if (timeout == -EINTR) {
+				/* arbitration lost */
+				return -EINTR;
+			}
 			i2c_stop(adap);
 			dev_err(&i2c_adap->dev, "i2c_write: error - timeout.\n");
 			return -EREMOTEIO; /* got a better one ?? */
@@ -247,11 +276,16 @@ static int pcf_readbytes(struct i2c_adapter *i2c_adap, char *buf,
 {
 	int i, status;
 	struct i2c_algo_pcf_data *adap = i2c_adap->algo_data;
+	int wfp;
 
 	/* increment number of bytes to read by one -- read dummy byte */
 	for (i = 0; i <= count; i++) {
 
-		if (wait_for_pin(adap, &status)) {
+		if ((wfp = wait_for_pin(adap, &status))) {
+			if (wfp == -EINTR) {
+				/* arbitration lost */
+				return -EINTR;
+			}
 			i2c_stop(adap);
 			dev_err(&i2c_adap->dev, "pcf_readbytes timed out.\n");
 			return (-1);
@@ -332,7 +366,7 @@ static inline int pcf_doAddress(struct i2c_algo_pcf_data *adap,
 }
 
 static int pcf_xfer(struct i2c_adapter *i2c_adap,
-		    struct i2c_msg msgs[], 
+		    struct i2c_msg *msgs, 
 		    int num)
 {
 	struct i2c_algo_pcf_data *adap = i2c_adap->algo_data;
@@ -366,6 +400,10 @@ static int pcf_xfer(struct i2c_adapter *i2c_adap,
 		/* Wait for PIN (pending interrupt NOT) */
 		timeout = wait_for_pin(adap, &status);
 		if (timeout) {
+			if (timeout == -EINTR) {
+				/* arbitration lost */
+				return (-EINTR);
+			}
 			i2c_stop(adap);
 			DEB2(printk(KERN_ERR "i2c-algo-pcf.o: Timeout waiting "
 				    "for PIN(1) in pcf_xfer\n");)
@@ -420,9 +458,7 @@ static u32 pcf_func(struct i2c_adapter *adap)
 
 /* -----exported algorithm data: -------------------------------------	*/
 
-static struct i2c_algorithm pcf_algo = {
-	.name		= "PCF8584 algorithm",
-	.id		= I2C_ALGO_PCF,
+static const struct i2c_algorithm pcf_algo = {
 	.master_xfer	= pcf_xfer,
 	.functionality	= pcf_func,
 };
@@ -438,27 +474,19 @@ int i2c_pcf_add_bus(struct i2c_adapter *adap)
 	DEB2(dev_dbg(&adap->dev, "hw routines registered.\n"));
 
 	/* register new adapter to i2c module... */
-
-	adap->id |= pcf_algo.id;
 	adap->algo = &pcf_algo;
 
 	adap->timeout = 100;		/* default values, should	*/
 	adap->retries = 3;		/* be replaced by defines	*/
 
-	rval = pcf_init_8584(pcf_adap);
-	if (!rval)
-		i2c_add_adapter(adap);
-	return rval;
-}
+	if ((rval = pcf_init_8584(pcf_adap)))
+		return rval;
 
+	rval = i2c_add_adapter(adap);
 
-int i2c_pcf_del_bus(struct i2c_adapter *adap)
-{
-	return i2c_del_adapter(adap);
+	return rval;
 }
-
 EXPORT_SYMBOL(i2c_pcf_add_bus);
-EXPORT_SYMBOL(i2c_pcf_del_bus);
 
 MODULE_AUTHOR("Hans Berglund <hb@spacetec.no>");
 MODULE_DESCRIPTION("I2C-Bus PCF8584 algorithm");