vserver 2.0 rc7

[linux-2.6.git] / drivers / i2c / algos / i2c-algo-pcf.c

diff --git a/drivers/i2c/algos/i2c-algo-pcf.c b/drivers/i2c/algos/i2c-algo-pcf.c
index fbbe1d2..8d087da 100644 (file)
--- 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");)