hwmon: (amc6821) Add support for fan1_target and pwm1_enable mode 4

After setting fan1_target and setting pwm1_enable to 4,
the fan controller tries to achieve the requested fan speed.

Reviewed-by: Quentin Schulz <quentin.schulz@cherry.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/Documentation/hwmon/amc6821.rst b/Documentation/hwmon/amc6821.rst
index 4ce67c268e52132b451ee4c68c21cbee9424a3a4..96e604c5ea8eaf0b97385f0744e687ee80f99232 100644 (file)
--- a/Documentation/hwmon/amc6821.rst
+++ b/Documentation/hwmon/amc6821.rst
@@ -48,12 +48,16 @@ fan1_min            rw      "
 fan1_max               rw      "
 fan1_fault             ro      "
 fan1_pulses            rw      Pulses per revolution can be either 2 or 4.
+fan1_target            rw      Target fan speed, to be used with pwm1_enable
+                               mode 4.
 
 pwm1                   rw      pwm1
 pwm1_enable            rw      regulator mode, 1=open loop, 2=fan controlled
                                by remote temperature, 3=fan controlled by
                                combination of the on-chip temperature and
                                remote-sensor temperature,
+                               4=fan controlled by target rpm set with
+                               fan1_target attribute.
 pwm1_auto_channels_temp ro     1 if pwm_enable==2, 3 if pwm_enable==3
 pwm1_auto_point1_pwm   ro      Hardwired to 0, shared for both
                                temperature channels.

diff --git a/drivers/hwmon/amc6821.c b/drivers/hwmon/amc6821.c
index 39bf52a5c432702734ded9c3c20355f6e4c569e8..9e9a70afbfd4bb730a20633c1ebd872584218df9 100644 (file)
--- a/drivers/hwmon/amc6821.c
+++ b/drivers/hwmon/amc6821.c
@@ -66,6 +66,8 @@ enum chips { amc6821 };
 #define AMC6821_REG_TACH_LLIMITH 0x11
 #define AMC6821_REG_TACH_HLIMITL 0x12
 #define AMC6821_REG_TACH_HLIMITH 0x13
+#define AMC6821_REG_TACH_SETTINGL 0x1e
+#define AMC6821_REG_TACH_SETTINGH 0x1f
 
 #define AMC6821_CONF1_START 0x01
 #define AMC6821_CONF1_FAN_INT_EN 0x02
@@ -122,17 +124,18 @@ static const u8 temp_reg[] = {AMC6821_REG_LTEMP_HI,
                        AMC6821_REG_RTEMP_LIMIT_MAX,
                        AMC6821_REG_RTEMP_CRIT, };
 
-enum {IDX_FAN1_INPUT = 0, IDX_FAN1_MIN, IDX_FAN1_MAX,
+enum {IDX_FAN1_INPUT = 0, IDX_FAN1_MIN, IDX_FAN1_MAX, IDX_FAN1_TARGET,
        FAN1_IDX_LEN, };
 
 static const u8 fan_reg_low[] = {AMC6821_REG_TDATA_LOW,
                        AMC6821_REG_TACH_LLIMITL,
-                       AMC6821_REG_TACH_HLIMITL, };
-
+                       AMC6821_REG_TACH_HLIMITL,
+                       AMC6821_REG_TACH_SETTINGL, };
 
 static const u8 fan_reg_hi[] = {AMC6821_REG_TDATA_HI,
                        AMC6821_REG_TACH_LLIMITH,
-                       AMC6821_REG_TACH_HLIMITH, };
+                       AMC6821_REG_TACH_HLIMITH,
+                       AMC6821_REG_TACH_SETTINGH, };
 
 /*
  * Client data (each client gets its own)
@@ -250,10 +253,10 @@ static struct amc6821_data *amc6821_update_device(struct device *dev)
                        break;
                case 1: /*
                         * semi-open loop: software sets rpm, chip controls
-                        * pwm1, currently not implemented
+                        * pwm1
                         */
                        data->pwm1_auto_channels_temp = 0;
-                       data->pwm1_enable = 0;
+                       data->pwm1_enable = 4;
                        break;
                }
 
@@ -407,6 +410,10 @@ static ssize_t pwm1_enable_store(struct device *dev,
                config |= AMC6821_CONF1_FDRC0;
                config |= AMC6821_CONF1_FDRC1;
                break;
+       case 4:
+               config |= AMC6821_CONF1_FDRC0;
+               config &= ~AMC6821_CONF1_FDRC1;
+               break;
        default:
                count = -EINVAL;
                goto unlock;
@@ -622,8 +629,8 @@ static ssize_t fan_store(struct device *dev, struct device_attribute *attr,
        if (ret)
                return ret;
 
-       /* The minimum fan speed must not be unlimited (0) */
-       if (ix == IDX_FAN1_MIN && !val)
+       /* Minimum and target fan speed must not be unlimited (0) */
+       if ((ix == IDX_FAN1_MIN || ix == IDX_FAN1_TARGET) && !val)
                return -EINVAL;
 
        val = val > 0 ? 6000000 / clamp_val(val, 1, 6000000) : 0;
@@ -713,6 +720,7 @@ static SENSOR_DEVICE_ATTR_RO(temp2_crit_alarm, temp_alarm, IDX_TEMP2_CRIT);
 static SENSOR_DEVICE_ATTR_RO(fan1_input, fan, IDX_FAN1_INPUT);
 static SENSOR_DEVICE_ATTR_RW(fan1_min, fan, IDX_FAN1_MIN);
 static SENSOR_DEVICE_ATTR_RW(fan1_max, fan, IDX_FAN1_MAX);
+static SENSOR_DEVICE_ATTR_RW(fan1_target, fan, IDX_FAN1_TARGET);
 static SENSOR_DEVICE_ATTR_RO(fan1_fault, fan1_fault, 0);
 static SENSOR_DEVICE_ATTR_RW(fan1_pulses, fan1_pulses, 0);
 
@@ -756,6 +764,7 @@ static struct attribute *amc6821_attrs[] = {
        &sensor_dev_attr_fan1_input.dev_attr.attr,
        &sensor_dev_attr_fan1_min.dev_attr.attr,
        &sensor_dev_attr_fan1_max.dev_attr.attr,
+       &sensor_dev_attr_fan1_target.dev_attr.attr,
        &sensor_dev_attr_fan1_fault.dev_attr.attr,
        &sensor_dev_attr_fan1_pulses.dev_attr.attr,
        &sensor_dev_attr_pwm1.dev_attr.attr,