4 files changed, 29 insertions, 21 deletions

diff --git a/drivers/i2c/busses/i2c-iop3xx.c b/drivers/i2c/busses/i2c-iop3xx.c
index aca7e1668605..48c56939c861 100644
--- a/drivers/i2c/busses/i2c-iop3xx.c
+++ b/drivers/i2c/busses/i2c-iop3xx.c
@@ -21,6 +21,9 @@
  * - Make it work with IXP46x chips
  * - Cleanup function names, coding style, etc
  *
+ * - writing to slave address causes latchup on iop331.
+ *      fix: driver refuses to address self.
+ *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, version 2.
@@ -73,12 +76,6 @@ iop3xx_i2c_reset(struct i2c_algo_iop3xx_data *iop3xx_adap)
 } 
 
 static void 
-iop3xx_i2c_set_slave_addr(struct i2c_algo_iop3xx_data *iop3xx_adap)
-{
-        __raw_writel(MYSAR, iop3xx_adap->ioaddr + SAR_OFFSET);
-}
-
-static void 
 iop3xx_i2c_enable(struct i2c_algo_iop3xx_data *iop3xx_adap)
 {
         u32 cr = IOP3XX_ICR_GCD | IOP3XX_ICR_SCLEN | IOP3XX_ICR_UE;
@@ -248,6 +245,13 @@ iop3xx_i2c_send_target_addr(struct i2c_algo_iop3xx_data *iop3xx_adap,
         int status;
         int rc;
 
+        /* avoid writing to my slave address (hangs on 80331),
+         * forbidden in Intel developer manual
+         */
+        if (msg->addr == MYSAR) {
+                return -EBUSY;
+        }
+
         __raw_writel(iic_cook_addr(msg), iop3xx_adap->ioaddr + DBR_OFFSET);
         
         cr &= ~(IOP3XX_ICR_MSTOP | IOP3XX_ICR_NACK);
@@ -498,7 +502,6 @@ iop3xx_i2c_probe(struct platform_device *pdev)
         spin_lock_init(&adapter_data->lock);
 
         iop3xx_i2c_reset(adapter_data);
-        iop3xx_i2c_set_slave_addr(adapter_data);
         iop3xx_i2c_enable(adapter_data);
 
         platform_set_drvdata(pdev, new_adapter);
diff --git a/drivers/i2c/busses/i2c-iop3xx.h b/drivers/i2c/busses/i2c-iop3xx.h
index e46ebaea7b1e..8485861f6a36 100644
--- a/drivers/i2c/busses/i2c-iop3xx.h
+++ b/drivers/i2c/busses/i2c-iop3xx.h
@@ -80,7 +80,7 @@
 #define IOP3XX_GPOD_I2C0        0x00c0  /* clear these bits to enable ch0 */
 #define IOP3XX_GPOD_I2C1        0x0030  /* clear these bits to enable ch1 */
 
-#define MYSAR                   0x02    /* SWAG a suitable slave address */
+#define MYSAR                   0       /* default slave address */
 
 #define I2C_ERR                 321
 #define I2C_ERR_BERR            (I2C_ERR+0)
diff --git a/drivers/i2c/busses/i2c-powermac.c b/drivers/i2c/busses/i2c-powermac.c
index 2a0b3be7cdd0..53bb43593863 100644
--- a/drivers/i2c/busses/i2c-powermac.c
+++ b/drivers/i2c/busses/i2c-powermac.c
@@ -148,8 +148,6 @@ static int i2c_powermac_master_xfer(	struct i2c_adapter *adap,
         int                     read;
         int                     addrdir;
 
-        if (num != 1)
-                return -EINVAL;
         if (msgs->flags & I2C_M_TEN)
                 return -EINVAL;
         read = (msgs->flags & I2C_M_RD) != 0;
@@ -166,7 +164,7 @@ static int i2c_powermac_master_xfer(	struct i2c_adapter *adap,
         rc = pmac_i2c_xfer(bus, addrdir, 0, 0, msgs->buf, msgs->len);
  bail:
         pmac_i2c_close(bus);
-        return rc < 0 ? rc : msgs->len;
+        return rc < 0 ? rc : 1;
 }
 
 static u32 i2c_powermac_func(struct i2c_adapter * adapter)
diff --git a/drivers/i2c/busses/scx200_acb.c b/drivers/i2c/busses/scx200_acb.c
index 22a3eda04166..eae9e81be375 100644
--- a/drivers/i2c/busses/scx200_acb.c
+++ b/drivers/i2c/busses/scx200_acb.c
@@ -184,21 +184,21 @@ static void scx200_acb_machine(struct scx200_acb_iface *iface, u8 status)
                 break;
 
         case state_read:
-                /* Set ACK if receiving the last byte */
-                if (iface->len == 1)
+                /* Set ACK if _next_ byte will be the last one */
+                if (iface->len == 2)
                         outb(inb(ACBCTL1) | ACBCTL1_ACK, ACBCTL1);
                 else
                         outb(inb(ACBCTL1) & ~ACBCTL1_ACK, ACBCTL1);
 
-                *iface->ptr++ = inb(ACBSDA);
-                --iface->len;
-
-                if (iface->len == 0) {
+                if (iface->len == 1) {
                         iface->result = 0;
                         iface->state = state_idle;
                         outb(inb(ACBCTL1) | ACBCTL1_STOP, ACBCTL1);
                 }
 
+                *iface->ptr++ = inb(ACBSDA);
+                --iface->len;
+
                 break;
 
         case state_write:
@@ -232,7 +232,7 @@ static void scx200_acb_poll(struct scx200_acb_iface *iface)
         unsigned long timeout;
 
         timeout = jiffies + POLL_TIMEOUT;
-        while (time_before(jiffies, timeout)) {
+        while (1) {
                 status = inb(ACBST);
 
                 /* Reset the status register to avoid the hang */
@@ -242,7 +242,10 @@ static void scx200_acb_poll(struct scx200_acb_iface *iface)
                         scx200_acb_machine(iface, status);
                         return;
                 }
-                yield();
+                if (time_after(jiffies, timeout))
+                        break;
+                cpu_relax();
+                cond_resched();
         }
 
         dev_err(&iface->adapter.dev, "timeout in state %s\n",
@@ -307,8 +310,12 @@ static s32 scx200_acb_smbus_xfer(struct i2c_adapter *adapter,
                 buffer = (u8 *)&cur_word;
                 break;
 
-        case I2C_SMBUS_BLOCK_DATA:
+        case I2C_SMBUS_I2C_BLOCK_DATA:
+                if (rw == I2C_SMBUS_READ)
+                        data->block[0] = I2C_SMBUS_BLOCK_MAX; /* For now */
                 len = data->block[0];
+                if (len == 0 || len > I2C_SMBUS_BLOCK_MAX)
+                        return -EINVAL;
                 buffer = &data->block[1];
                 break;
 
@@ -372,7 +379,7 @@ static u32 scx200_acb_func(struct i2c_adapter *adapter)
 {
         return I2C_FUNC_SMBUS_QUICK | I2C_FUNC_SMBUS_BYTE |
                I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA |
-               I2C_FUNC_SMBUS_BLOCK_DATA;
+               I2C_FUNC_SMBUS_I2C_BLOCK;
 }
 
 /* For now, we only handle combined mode (smbus) */