hwmon: (w83627ehf) Disable setting DC mode for pwm2, pwm3 on NCT6776F

NCT6776F only supports pwm mode for pwm2 and pwm3. Return error if an attempt
is made to set those pwm channels to DC mode.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Jean Delvare <khali@linux-fr.org>
Cc: stable@vger.kernel.org # 3.0+
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>

diff --git a/drivers/hwmon/w83627ehf.c b/drivers/hwmon/w83627ehf.c
index 0e0af0445222c4346af8fef879831831e49caffa..2dfae7d7cc5b400946eba8db5f4445a43cb6a8b8 100644 (file)
--- a/drivers/hwmon/w83627ehf.c
+++ b/drivers/hwmon/w83627ehf.c
@@ -1319,6 +1319,7 @@ store_pwm_mode(struct device *dev, struct device_attribute *attr,
 {
        struct w83627ehf_data *data = dev_get_drvdata(dev);
        struct sensor_device_attribute *sensor_attr = to_sensor_dev_attr(attr);
+       struct w83627ehf_sio_data *sio_data = dev->platform_data;
        int nr = sensor_attr->index;
        unsigned long val;
        int err;
@@ -1330,6 +1331,11 @@ store_pwm_mode(struct device *dev, struct device_attribute *attr,
 
        if (val > 1)
                return -EINVAL;
+
+       /* On NCT67766F, DC mode is only supported for pwm1 */
+       if (sio_data->kind == nct6776 && nr && val != 1)
+               return -EINVAL;
+
        mutex_lock(&data->update_lock);
        reg = w83627ehf_read_value(data, W83627EHF_REG_PWM_ENABLE[nr]);
        data->pwm_mode[nr] = val;