diff options
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/max31790.c | 41 |
1 files changed, 26 insertions, 15 deletions
diff --git a/drivers/hwmon/max31790.c b/drivers/hwmon/max31790.c index 693497e09ac0..67677c437768 100644 --- a/drivers/hwmon/max31790.c +++ b/drivers/hwmon/max31790.c @@ -27,6 +27,7 @@ /* Fan Config register bits */ #define MAX31790_FAN_CFG_RPM_MODE 0x80 +#define MAX31790_FAN_CFG_CTRL_MON 0x10 #define MAX31790_FAN_CFG_TACH_INPUT_EN 0x08 #define MAX31790_FAN_CFG_TACH_INPUT 0x01 @@ -271,12 +272,12 @@ static int max31790_read_pwm(struct device *dev, u32 attr, int channel, *val = data->pwm[channel] >> 8; return 0; case hwmon_pwm_enable: - if (fan_config & MAX31790_FAN_CFG_RPM_MODE) + if (fan_config & MAX31790_FAN_CFG_CTRL_MON) + *val = 0; + else if (fan_config & MAX31790_FAN_CFG_RPM_MODE) *val = 2; - else if (fan_config & MAX31790_FAN_CFG_TACH_INPUT_EN) - *val = 1; else - *val = 0; + *val = 1; return 0; default: return -EOPNOTSUPP; @@ -307,23 +308,33 @@ static int max31790_write_pwm(struct device *dev, u32 attr, int channel, case hwmon_pwm_enable: fan_config = data->fan_config[channel]; if (val == 0) { - fan_config &= ~(MAX31790_FAN_CFG_TACH_INPUT_EN | - MAX31790_FAN_CFG_RPM_MODE); + fan_config |= MAX31790_FAN_CFG_CTRL_MON; + /* + * Disable RPM mode; otherwise disabling fan speed + * monitoring is not possible. + */ + fan_config &= ~MAX31790_FAN_CFG_RPM_MODE; } else if (val == 1) { - fan_config = (fan_config | - MAX31790_FAN_CFG_TACH_INPUT_EN) & - ~MAX31790_FAN_CFG_RPM_MODE; + fan_config &= ~(MAX31790_FAN_CFG_CTRL_MON | MAX31790_FAN_CFG_RPM_MODE); } else if (val == 2) { - fan_config |= MAX31790_FAN_CFG_TACH_INPUT_EN | - MAX31790_FAN_CFG_RPM_MODE; + fan_config &= ~MAX31790_FAN_CFG_CTRL_MON; + /* + * The chip sets MAX31790_FAN_CFG_TACH_INPUT_EN on its + * own if MAX31790_FAN_CFG_RPM_MODE is set. + * Do it here as well to reflect the actual register + * value in the cache. + */ + fan_config |= (MAX31790_FAN_CFG_RPM_MODE | MAX31790_FAN_CFG_TACH_INPUT_EN); } else { err = -EINVAL; break; } - data->fan_config[channel] = fan_config; - err = i2c_smbus_write_byte_data(client, - MAX31790_REG_FAN_CONFIG(channel), - fan_config); + if (fan_config != data->fan_config[channel]) { + err = i2c_smbus_write_byte_data(client, MAX31790_REG_FAN_CONFIG(channel), + fan_config); + if (!err) + data->fan_config[channel] = fan_config; + } break; default: err = -EOPNOTSUPP; |