Hi,
Do you know why there is 2 methods of probing i2c [1] and [2], with different
quirks for eeprom.
Why can't they be merged together ?
Thanks
Matthieu
PS : please keep me in CC
[1]
i2c_detect_address
/* Make sure the address is valid */
if (addr < 0x03 || addr > 0x77) {
dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n",
addr);
return -EINVAL;
}
/* Skip if already in use */
if (i2c_check_addr(adapter, addr))
return 0;
/* Make sure there is something at this address */
if (i2c_smbus_xfer(adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL) < 0)
return 0;
/* Prevent 24RF08 corruption */
if ((addr & ~0x0f) == 0x50)
i2c_smbus_xfer(adapter, addr, 0, 0, 0, I2C_SMBUS_QUICK, NULL);
[2]
i2c_new_probed_device
if (addr_list[i] < 0x03 || addr_list[i] > 0x77) {
dev_warn(&adap->dev, "Invalid 7-bit address "
"0x%02x\n", addr_list[i]);
continue;
}
/* Check address availability */
if (i2c_check_addr(adap, addr_list[i])) {
dev_dbg(&adap->dev, "Address 0x%02x already in "
"use, not probing\n", addr_list[i]);
continue;
}
/* Test address responsiveness
The default probe method is a quick write, but it is known
to corrupt the 24RF08 EEPROMs due to a state machine bug,
and could also irreversibly write-protect some EEPROMs, so
for address ranges 0x30-0x37 and 0x50-0x5f, we use a byte
read instead. Also, some bus drivers don't implement
quick write, so we fallback to a byte read it that case
too. */
if ((addr_list[i] & ~0x07) == 0x30
|| (addr_list[i] & ~0x0f) == 0x50
|| !i2c_check_functionality(adap, I2C_FUNC_SMBUS_QUICK)) {
union i2c_smbus_data data;
if (i2c_smbus_xfer(adap, addr_list[i], 0,
I2C_SMBUS_READ, 0,
I2C_SMBUS_BYTE, &data) >= 0)
break;
} else {
if (i2c_smbus_xfer(adap, addr_list[i], 0,
I2C_SMBUS_WRITE, 0,
I2C_SMBUS_QUICK, NULL) >= 0)
break;
}
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