#define I2C_TIMEOUT (CFG_HZ / 4)
+#define I2C_READ_BIT 1
+#define I2C_WRITE_BIT 0
+
/* Initialize the bus pointer to whatever one the SPD EEPROM is on.
* Default is bus 0. This is necessary because the DDR initialization
* runs from ROM, and we can't switch buses because we can't modify
dev = (struct fsl_i2c *) (CFG_IMMR + CFG_I2C_OFFSET);
writeb(0, &dev->cr); /* stop I2C controller */
+ udelay(5); /* let it shutdown in peace */
writeb(0x3F, &dev->fdr); /* set bus speed */
writeb(0x3F, &dev->dfsrr); /* set default filter */
- writeb(slaveadd, &dev->adr); /* write slave address */
+ writeb(slaveadd << 1, &dev->adr); /* write slave address */
writeb(0x0, &dev->sr); /* clear status register */
writeb(I2C_CR_MEN, &dev->cr); /* start I2C controller */
dev = (struct fsl_i2c *) (CFG_IMMR + CFG_I2C2_OFFSET);
writeb(0, &dev->cr); /* stop I2C controller */
+ udelay(5); /* let it shutdown in peace */
writeb(0x3F, &dev->fdr); /* set bus speed */
writeb(0x3F, &dev->dfsrr); /* set default filter */
- writeb(slaveadd, &dev->adr); /* write slave address */
+ writeb(slaveadd << 1, &dev->adr); /* write slave address */
writeb(0x0, &dev->sr); /* clear status register */
writeb(I2C_CR_MEN, &dev->cr); /* start I2C controller */
#endif /* CFG_I2C2_OFFSET */
return -1;
}
- if (write == I2C_WRITE && (csr & I2C_SR_RXAK)) {
+ if (write == I2C_WRITE_BIT && (csr & I2C_SR_RXAK)) {
debug("i2c_wait: No RXACK\n");
return -1;
}
writeb((dev << 1) | dir, &i2c_dev[i2c_bus_num]->dr);
- if (i2c_wait(I2C_WRITE) < 0)
+ if (i2c_wait(I2C_WRITE_BIT) < 0)
return 0;
return 1;
for (i = 0; i < length; i++) {
writeb(data[i], &i2c_dev[i2c_bus_num]->dr);
- if (i2c_wait(I2C_WRITE) < 0)
+ if (i2c_wait(I2C_WRITE_BIT) < 0)
break;
}
readb(&i2c_dev[i2c_bus_num]->dr);
for (i = 0; i < length; i++) {
- if (i2c_wait(I2C_READ) < 0)
+ if (i2c_wait(I2C_READ_BIT) < 0)
break;
/* Generate ack on last next to last byte */
int
i2c_read(u8 dev, uint addr, int alen, u8 *data, int length)
{
- int i = 0;
+ int i = -1; /* signal error */
u8 *a = (u8*)&addr;
if (i2c_wait4bus() >= 0
- && i2c_write_addr(dev, I2C_WRITE, 0) != 0
- && __i2c_write(&a[4 - alen], alen) == alen
- && i2c_write_addr(dev, I2C_READ, 1) != 0) {
+ && i2c_write_addr(dev, I2C_WRITE_BIT, 0) != 0
+ && __i2c_write(&a[4 - alen], alen) == alen)
+ i = 0; /* No error so far */
+
+ if (length
+ && i2c_write_addr(dev, I2C_READ_BIT, 1) != 0)
i = __i2c_read(data, length);
- }
writeb(I2C_CR_MEN, &i2c_dev[i2c_bus_num]->cr);
int
i2c_write(u8 dev, uint addr, int alen, u8 *data, int length)
{
- int i = 0;
+ int i = -1; /* signal error */
u8 *a = (u8*)&addr;
if (i2c_wait4bus() >= 0
- && i2c_write_addr(dev, I2C_WRITE, 0) != 0
+ && i2c_write_addr(dev, I2C_WRITE_BIT, 0) != 0
&& __i2c_write(&a[4 - alen], alen) == alen) {
i = __i2c_write(data, length);
}
int
i2c_probe(uchar chip)
{
- int tmp;
-
- /*
- * Try to read the first location of the chip. The underlying
- * driver doesn't appear to support sending just the chip address
- * and looking for an <ACK> back.
+ /* For unknow reason the controller will ACK when
+ * probing for a slave with the same address, so skip
+ * it.
*/
- udelay(10000);
+ if (chip == (readb(&i2c_dev[i2c_bus_num]->adr) >> 1))
+ return -1;
- return i2c_read(chip, 0, 1, (uchar *)&tmp, 1);
+ return i2c_read(chip, 0, 0, NULL, 0);
}
uchar