In IT8620E, after setting pwm control to manual, it was observed that pwm values for fan 4..6 have reversed results (writing 0 results in fans running at full speed, writing 255 results in fans turned off). With the new PWM control, pwm polarity for pwm control 4..6 is specified in its pwm control registers. Those registers are overwritten when setting the pwm mode or the temperature mapping. Do not touch bit 2..6 of pwm control registers on register writes to fix the problem. Cc: stable@xxxxxxxxxxxxxxx # 4.9+ Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx> --- drivers/hwmon/it87.c | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-) diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c index 4f3fabcd470d..37acb38b5e17 100644 --- a/drivers/hwmon/it87.c +++ b/drivers/hwmon/it87.c @@ -1316,25 +1316,35 @@ static ssize_t set_pwm_enable(struct device *dev, struct device_attribute *attr, it87_write_value(data, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl); } else { + u8 ctrl; + /* No on/off mode, set maximum pwm value */ data->pwm_duty[nr] = pwm_to_reg(data, 0xff); it87_write_value(data, IT87_REG_PWM_DUTY[nr], data->pwm_duty[nr]); /* and set manual mode */ - data->pwm_ctrl[nr] = has_newer_autopwm(data) ? - data->pwm_temp_map[nr] : - data->pwm_duty[nr]; - it87_write_value(data, IT87_REG_PWM[nr], - data->pwm_ctrl[nr]); + if (has_newer_autopwm(data)) { + ctrl = (data->pwm_ctrl[nr] & 0x7c) | + data->pwm_temp_map[nr]; + } else { + ctrl = data->pwm_duty[nr]; + } + data->pwm_ctrl[nr] = ctrl; + it87_write_value(data, IT87_REG_PWM[nr], ctrl); } } else { - if (val == 1) /* Manual mode */ - data->pwm_ctrl[nr] = has_newer_autopwm(data) ? - data->pwm_temp_map[nr] : - data->pwm_duty[nr]; - else /* Automatic mode */ - data->pwm_ctrl[nr] = 0x80 | data->pwm_temp_map[nr]; - it87_write_value(data, IT87_REG_PWM[nr], data->pwm_ctrl[nr]); + u8 ctrl; + + if (has_newer_autopwm(data)) { + ctrl = (data->pwm_ctrl[nr] & 0x7c) | + data->pwm_temp_map[nr]; + if (val != 1) + ctrl |= 0x80; + } else { + ctrl = (val == 1 ? data->pwm_duty[nr] : 0x80); + } + data->pwm_ctrl[nr] = ctrl; + it87_write_value(data, IT87_REG_PWM[nr], ctrl); if (data->type != it8603 && nr < 3) { /* set SmartGuardian mode */ @@ -1480,7 +1490,8 @@ static ssize_t set_pwm_temp_map(struct device *dev, * otherwise, just store it for later use. */ if (data->pwm_ctrl[nr] & 0x80) { - data->pwm_ctrl[nr] = 0x80 | data->pwm_temp_map[nr]; + data->pwm_ctrl[nr] = (data->pwm_ctrl[nr] & 0xfc) | + data->pwm_temp_map[nr]; it87_write_value(data, IT87_REG_PWM[nr], data->pwm_ctrl[nr]); } mutex_unlock(&data->update_lock); -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html