hwmon: (pmbus) Improve fan detection
authorGuenter Roeck <guenter.roeck@ericsson.com>
Thu, 30 Jun 2011 13:54:05 +0000 (06:54 -0700)
committerGuenter Roeck <guenter.roeck@ericsson.com>
Fri, 1 Jul 2011 22:56:06 +0000 (15:56 -0700)
Some PMBus devices return no error when reading fan speed registers, but don't
really support fans. Strengthen fan detection by also checking if fan
configuration registers exist.

Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
Reviewed-by: Robert Coulson <robert.coulson@ericsson.com>
Cc: stable.kernel.org # 2.6.39
drivers/hwmon/pmbus.c

index 98e2e28899e2cd24f07d2eac0095479745d23a1d..b0ea00b75f173556be047b9cba69359e1b512e00 100644 (file)
@@ -47,12 +47,14 @@ static void pmbus_find_sensor_groups(struct i2c_client *client,
        if (info->func[0]
            && pmbus_check_byte_register(client, 0, PMBUS_STATUS_INPUT))
                info->func[0] |= PMBUS_HAVE_STATUS_INPUT;
-       if (pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
+       if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_12) &&
+           pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_1)) {
                info->func[0] |= PMBUS_HAVE_FAN12;
                if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_12))
                        info->func[0] |= PMBUS_HAVE_STATUS_FAN12;
        }
-       if (pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
+       if (pmbus_check_byte_register(client, 0, PMBUS_FAN_CONFIG_34) &&
+           pmbus_check_word_register(client, 0, PMBUS_READ_FAN_SPEED_3)) {
                info->func[0] |= PMBUS_HAVE_FAN34;
                if (pmbus_check_byte_register(client, 0, PMBUS_STATUS_FAN_34))
                        info->func[0] |= PMBUS_HAVE_STATUS_FAN34;