Move strict I2C address validity check to a single function, and document the reserved I2C addresses there. Signed-off-by: Jean Delvare <khali@xxxxxxxxxxxx> Cc: Hans Verkuil <hverkuil@xxxxxxxxx> --- drivers/i2c/i2c-core.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-) --- linux-2.6.35-rc0.orig/drivers/i2c/i2c-core.c 2010-05-30 16:17:56.000000000 +0200 +++ linux-2.6.35-rc0/drivers/i2c/i2c-core.c 2010-05-30 16:17:58.000000000 +0200 @@ -387,6 +387,27 @@ static int i2c_check_client_addr_validit return 0; } +/* And this is a strict address validity check, used when probing. If a + * device uses a reserved address, then it shouldn't be probed. 7-bit + * addressing is assumed, 10-bit address devices are rare and should be + * explicitly enumerated. */ +static int i2c_check_addr_validity(unsigned short addr) +{ + /* + * Reserved addresses per I2C specification: + * 0x00 General call address / START byte + * 0x01 CBUS address + * 0x02 Reserved for different bus format + * 0x03 Reserved for future purposes + * 0x04-0x07 Hs-mode master code + * 0x78-0x7b 10-bit slave addressing + * 0x7c-0x7f Reserved for future purposes + */ + if (addr < 0x08 || addr > 0x77) + return -EINVAL; + return 0; +} + /** * i2c_new_device - instantiate an i2c device * @adap: the adapter managing the device @@ -1340,10 +1361,11 @@ static int i2c_detect_address(struct i2c int err; /* Make sure the address is valid */ - if (addr < 0x03 || addr > 0x77) { + err = i2c_check_addr_validity(addr); + if (err) { dev_warn(&adapter->dev, "Invalid probe address 0x%02x\n", addr); - return -EINVAL; + return err; } /* Skip if already in use */ @@ -1446,7 +1468,7 @@ i2c_new_probed_device(struct i2c_adapter for (i = 0; addr_list[i] != I2C_CLIENT_END; i++) { /* Check address validity */ - if (addr_list[i] < 0x03 || addr_list[i] > 0x77) { + if (i2c_check_addr_validity(addr_list[i]) < 0) { dev_warn(&adap->dev, "Invalid 7-bit address " "0x%02x\n", addr_list[i]); continue; -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html