diff options
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/max6650.c | 55 |
1 files changed, 27 insertions, 28 deletions
diff --git a/drivers/hwmon/max6650.c b/drivers/hwmon/max6650.c index e540d0b0145e..461484e7828a 100644 --- a/drivers/hwmon/max6650.c +++ b/drivers/hwmon/max6650.c @@ -92,7 +92,8 @@ module_param(clock, int, 0444); #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) @@ -136,6 +137,22 @@ static const struct of_device_id __maybe_unused max6650_dt_match[] = { }; 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); @@ -343,22 +360,10 @@ static ssize_t fan1_target_store(struct device *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, @@ -369,6 +374,7 @@ 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) @@ -377,13 +383,10 @@ static ssize_t pwm1_store(struct device *dev, 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; @@ -714,11 +717,7 @@ static int max6650_set_cur_state(struct thermal_cooling_device *cdev, 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) { @@ -730,7 +729,7 @@ static int max6650_set_cur_state(struct thermal_cooling_device *cdev, mutex_unlock(&data->update_lock); - return err < 0 ? err : 0; + return err; } static const struct thermal_cooling_device_ops max6650_cooling_ops = { |