hwmon: (pmbus) Improve fan detection
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
diff --git a/drivers/hwmon/pmbus.c b/drivers/hwmon/pmbus.c
index 98e2e28..b0ea00b 100644
--- a/drivers/hwmon/pmbus.c
+++ b/drivers/hwmon/pmbus.c
@@ -47,12 +47,14 @@
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;