#define FAN_RPM_MIN 240
#define FAN_RPM_MAX 30000
-#define DIV_FROM_REG(reg) (1 << (reg & 7))
+#define DIV_FROM_REG(reg) (1 << ((reg) & 7))
+#define DAC_LIMIT(v12) ((v12) ? 180 : 76)
/*
* Client data (each client gets its own)
};
MODULE_DEVICE_TABLE(of, max6650_dt_match);
+static int dac_to_pwm(int dac, bool v12)
+{
+ /*
+ * Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans.
+ * Lower DAC values mean higher speeds.
+ */
+ return clamp_val(255 - (255 * dac) / DAC_LIMIT(v12), 0, 255);
+}
+
+static u8 pwm_to_dac(unsigned int pwm, bool v12)
+{
+ int limit = DAC_LIMIT(v12);
+
+ return limit - (limit * pwm) / 255;
+}
+
static struct max6650_data *max6650_update_device(struct device *dev)
{
struct max6650_data *data = dev_get_drvdata(dev);
static ssize_t pwm1_show(struct device *dev, struct device_attribute *devattr,
char *buf)
{
- int pwm;
struct max6650_data *data = max6650_update_device(dev);
- /*
- * Useful range for dac is 0-180 for 12V fans and 0-76 for 5V fans.
- * Lower DAC values mean higher speeds.
- */
- if (data->config & MAX6650_CFG_V12)
- pwm = 255 - (255 * (int)data->dac)/180;
- else
- pwm = 255 - (255 * (int)data->dac)/76;
-
- if (pwm < 0)
- pwm = 0;
-
- return sprintf(buf, "%d\n", pwm);
+ return sprintf(buf, "%d\n", dac_to_pwm(data->dac,
+ data->config & MAX6650_CFG_V12));
}
static ssize_t pwm1_store(struct device *dev,
struct i2c_client *client = data->client;
unsigned long pwm;
int err;
+ u8 dac;
err = kstrtoul(buf, 10, &pwm);
if (err)
pwm = clamp_val(pwm, 0, 255);
mutex_lock(&data->update_lock);
-
- if (data->config & MAX6650_CFG_V12)
- data->dac = 180 - (180 * pwm)/255;
- else
- data->dac = 76 - (76 * pwm)/255;
- err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
-
+ dac = pwm_to_dac(pwm, data->config & MAX6650_CFG_V12);
+ err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, dac);
+ if (!err)
+ data->dac = dac;
mutex_unlock(&data->update_lock);
return err < 0 ? err : count;
mutex_lock(&data->update_lock);
- if (data->config & MAX6650_CFG_V12)
- data->dac = 180 - (180 * state)/255;
- else
- data->dac = 76 - (76 * state)/255;
-
+ data->dac = pwm_to_dac(state, data->config & MAX6650_CFG_V12);
err = i2c_smbus_write_byte_data(client, MAX6650_REG_DAC, data->dac);
if (!err) {
mutex_unlock(&data->update_lock);
- return err < 0 ? err : 0;
+ return err;
}
static const struct thermal_cooling_device_ops max6650_cooling_ops = {