hwmon/f71805f: Add manual fan speed control

pwmN files are writable only in manual fan speed control mode.
In automatic fan speed control modes, they are read-only and
report the duty cycle chosen by the chip.

Signed-off-by: Jean Delvare <khali@linux-fr.org>

1 files changed, 144 insertions, 1 deletions

diff --git a/drivers/hwmon/f71805f.c b/drivers/hwmon/f71805f.c
index dfca856854c3..6e6542036c6a 100644
--- a/drivers/hwmon/f71805f.c
+++ b/drivers/hwmon/f71805f.c
@@ -112,6 +112,7 @@ superio_exit(int base)
 #define F71805F_REG_FAN(nr)             (0x20 + 2 * (nr))
 #define F71805F_REG_FAN_LOW(nr)         (0x28 + 2 * (nr))
 #define F71805F_REG_FAN_CTRL(nr)        (0x60 + 16 * (nr))
+#define F71805F_REG_PWM_DUTY(nr)        (0x6B + 16 * (nr))
 /* temp nr from 0 to 2 (8-bit values) */
 #define F71805F_REG_TEMP(nr)            (0x1B + (nr))
 #define F71805F_REG_TEMP_HIGH(nr)       (0x54 + 2 * (nr))
@@ -124,6 +125,10 @@ superio_exit(int base)
 
 /* individual register bits */
 #define FAN_CTRL_SKIP                   0x80
+#define FAN_CTRL_MODE_MASK              0x03
+#define FAN_CTRL_MODE_SPEED             0x00
+#define FAN_CTRL_MODE_TEMPERATURE       0x01
+#define FAN_CTRL_MODE_MANUAL            0x02
 
 /*
  * Data structures and manipulation thereof
@@ -147,6 +152,7 @@ struct f71805f_data {
         u16 fan[3];
         u16 fan_low[3];
         u8 fan_ctrl[3];
+        u8 pwm[3];
         u8 temp[3];
         u8 temp_high[3];
         u8 temp_hyst[3];
@@ -312,6 +318,10 @@ static struct f71805f_data *f71805f_update_device(struct device *dev)
                                 continue;
                         data->fan[nr] = f71805f_read16(data,
                                         F71805F_REG_FAN(nr));
+                        data->fan_ctrl[nr] = f71805f_read8(data,
+                                             F71805F_REG_FAN_CTRL(nr));
+                        data->pwm[nr] = f71805f_read8(data,
+                                        F71805F_REG_PWM_DUTY(nr));
                 }
                 for (nr = 0; nr < 3; nr++) {
                         data->temp[nr] = f71805f_read8(data,
@@ -484,6 +494,104 @@ static ssize_t set_fan_min(struct device *dev, struct device_attribute
         return count;
 }
 
+static ssize_t show_pwm(struct device *dev, struct device_attribute *devattr,
+                        char *buf)
+{
+        struct f71805f_data *data = f71805f_update_device(dev);
+        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+        int nr = attr->index;
+
+        return sprintf(buf, "%d\n", (int)data->pwm[nr]);
+}
+
+static ssize_t show_pwm_enable(struct device *dev, struct device_attribute
+                               *devattr, char *buf)
+{
+        struct f71805f_data *data = f71805f_update_device(dev);
+        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+        int nr = attr->index;
+        int mode;
+
+        switch (data->fan_ctrl[nr] & FAN_CTRL_MODE_MASK) {
+        case FAN_CTRL_MODE_SPEED:
+                mode = 3;
+                break;
+        case FAN_CTRL_MODE_TEMPERATURE:
+                mode = 2;
+                break;
+        default: /* MANUAL */
+                mode = 1;
+        }
+
+        return sprintf(buf, "%d\n", mode);
+}
+
+static ssize_t set_pwm(struct device *dev, struct device_attribute *devattr,
+                       const char *buf, size_t count)
+{
+        struct f71805f_data *data = dev_get_drvdata(dev);
+        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+        int nr = attr->index;
+        unsigned long val = simple_strtoul(buf, NULL, 10);
+
+        if (val > 255)
+                return -EINVAL;
+
+        mutex_lock(&data->update_lock);
+        data->pwm[nr] = val;
+        f71805f_write8(data, F71805F_REG_PWM_DUTY(nr), data->pwm[nr]);
+        mutex_unlock(&data->update_lock);
+
+        return count;
+}
+
+static struct attribute *f71805f_attr_pwm[];
+
+static ssize_t set_pwm_enable(struct device *dev, struct device_attribute
+                              *devattr, const char *buf, size_t count)
+{
+        struct f71805f_data *data = dev_get_drvdata(dev);
+        struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
+        int nr = attr->index;
+        unsigned long val = simple_strtoul(buf, NULL, 10);
+        u8 reg;
+
+        if (val < 1 || val > 3)
+                return -EINVAL;
+
+        if (val > 1) { /* Automatic mode, user can't set PWM value */
+                if (sysfs_chmod_file(&dev->kobj, f71805f_attr_pwm[nr],
+                                     S_IRUGO))
+                        dev_dbg(dev, "chmod -w pwm%d failed\n", nr + 1);
+        }
+
+        mutex_lock(&data->update_lock);
+        reg = f71805f_read8(data, F71805F_REG_FAN_CTRL(nr))
+            & ~FAN_CTRL_MODE_MASK;
+        switch (val) {
+        case 1:
+                reg |= FAN_CTRL_MODE_MANUAL;
+                break;
+        case 2:
+                reg |= FAN_CTRL_MODE_TEMPERATURE;
+                break;
+        case 3:
+                reg |= FAN_CTRL_MODE_SPEED;
+                break;
+        }
+        data->fan_ctrl[nr] = reg;
+        f71805f_write8(data, F71805F_REG_FAN_CTRL(nr), reg);
+        mutex_unlock(&data->update_lock);
+
+        if (val == 1) { /* Manual mode, user can set PWM value */
+                if (sysfs_chmod_file(&dev->kobj, f71805f_attr_pwm[nr],
+                                     S_IRUGO | S_IWUSR))
+                        dev_dbg(dev, "chmod +w pwm%d failed\n", nr + 1);
+        }
+
+        return count;
+}
+
 static ssize_t show_temp(struct device *dev, struct device_attribute *devattr,
                          char *buf)
 {
@@ -672,6 +780,18 @@ static SENSOR_DEVICE_ATTR(temp3_max_hyst, S_IRUGO | S_IWUSR,
                     show_temp_hyst, set_temp_hyst, 2);
 static SENSOR_DEVICE_ATTR(temp3_type, S_IRUGO, show_temp_type, NULL, 2);
 
+/* pwm (value) files are created read-only, write permission is
+   then added or removed dynamically as needed */
+static SENSOR_DEVICE_ATTR(pwm1, S_IRUGO, show_pwm, set_pwm, 0);
+static SENSOR_DEVICE_ATTR(pwm1_enable, S_IRUGO | S_IWUSR,
+                          show_pwm_enable, set_pwm_enable, 0);
+static SENSOR_DEVICE_ATTR(pwm2, S_IRUGO, show_pwm, set_pwm, 1);
+static SENSOR_DEVICE_ATTR(pwm2_enable, S_IRUGO | S_IWUSR,
+                          show_pwm_enable, set_pwm_enable, 1);
+static SENSOR_DEVICE_ATTR(pwm3, S_IRUGO, show_pwm, set_pwm, 2);
+static SENSOR_DEVICE_ATTR(pwm3_enable, S_IRUGO | S_IWUSR,
+                          show_pwm_enable, set_pwm_enable, 2);
+
 static SENSOR_DEVICE_ATTR(in0_alarm, S_IRUGO, show_alarm, NULL, 0);
 static SENSOR_DEVICE_ATTR(in1_alarm, S_IRUGO, show_alarm, NULL, 1);
 static SENSOR_DEVICE_ATTR(in2_alarm, S_IRUGO, show_alarm, NULL, 2);
@@ -759,21 +879,27 @@ static const struct attribute_group f71805f_group = {
         .attrs = f71805f_attributes,
 };
 
-static struct attribute *f71805f_attributes_fan[3][4] = {
+static struct attribute *f71805f_attributes_fan[3][6] = {
         {
                 &sensor_dev_attr_fan1_input.dev_attr.attr,
                 &sensor_dev_attr_fan1_min.dev_attr.attr,
                 &sensor_dev_attr_fan1_alarm.dev_attr.attr,
+                &sensor_dev_attr_pwm1.dev_attr.attr,
+                &sensor_dev_attr_pwm1_enable.dev_attr.attr,
                 NULL
         }, {
                 &sensor_dev_attr_fan2_input.dev_attr.attr,
                 &sensor_dev_attr_fan2_min.dev_attr.attr,
                 &sensor_dev_attr_fan2_alarm.dev_attr.attr,
+                &sensor_dev_attr_pwm2.dev_attr.attr,
+                &sensor_dev_attr_pwm2_enable.dev_attr.attr,
                 NULL
         }, {
                 &sensor_dev_attr_fan3_input.dev_attr.attr,
                 &sensor_dev_attr_fan3_min.dev_attr.attr,
                 &sensor_dev_attr_fan3_alarm.dev_attr.attr,
+                &sensor_dev_attr_pwm3.dev_attr.attr,
+                &sensor_dev_attr_pwm3_enable.dev_attr.attr,
                 NULL
         }
 };
@@ -784,6 +910,13 @@ static const struct attribute_group f71805f_group_fan[3] = {
         { .attrs = f71805f_attributes_fan[2] },
 };
 
+/* We also need an indexed access to pwmN files to toggle writability */
+static struct attribute *f71805f_attr_pwm[] = {
+        &sensor_dev_attr_pwm1.dev_attr.attr,
+        &sensor_dev_attr_pwm2.dev_attr.attr,
+        &sensor_dev_attr_pwm3.dev_attr.attr,
+};
+
 /*
  * Device registration and initialization
  */
@@ -840,6 +973,16 @@ static int __devinit f71805f_probe(struct platform_device *pdev)
                 if ((err = sysfs_create_group(&pdev->dev.kobj,
                                               &f71805f_group_fan[i])))
                         goto exit_remove_files;
+                /* If PWM is in manual mode, add write permission */
+                if (data->fan_ctrl[i] & FAN_CTRL_MODE_MANUAL) {
+                        if ((err = sysfs_chmod_file(&pdev->dev.kobj,
+                                                    f71805f_attr_pwm[i],
+                                                    S_IRUGO | S_IWUSR))) {
+                                dev_err(&pdev->dev, "chmod +w pwm%d failed\n",
+                                        i + 1);
+                                goto exit_remove_files;
+                        }
+                }
         }
 
         data->class_dev = hwmon_device_register(&pdev->dev);