hwmon/it87: Add PWM base frequency control (f8d0c19a) · Commits · e / devices / android_kernel_fairphone_FP4

Documentation/hwmon/it87

+10 −0

Original line number	Original line	Diff line number	Diff line
	@@ -135,6 +135,16 @@ Give 0 for unused sensor. Any other value is invalid. To configure this at
	startup, consult lm_sensors's /etc/sensors.conf. (2 = thermistor;		startup, consult lm_sensors's /etc/sensors.conf. (2 = thermistor;
	3 = thermal diode)		3 = thermal diode)


			Fan speed control
			-----------------

	The fan speed control features are limited to manual PWM mode. Automatic		The fan speed control features are limited to manual PWM mode. Automatic
	"Smart Guardian" mode control handling is not implemented. However		"Smart Guardian" mode control handling is not implemented. However
	if you want to go for "manual mode" just write 1 to pwmN_enable.		if you want to go for "manual mode" just write 1 to pwmN_enable.

			If you are only able to control the fan speed with very small PWM values,
			try lowering the PWM base frequency (pwm1_freq). Depending on the fan,
			it may give you a somewhat greater control range. The same frequency is
			used to drive all fan outputs, which is why pwm2_freq and pwm3_freq are
			read-only.

Documentation/hwmon/sysfs-interface

+10 −5

Original line number	Original line	Diff line number	Diff line
	@@ -166,16 +166,21 @@ pwm[1-*] Pulse width modulation fan control.

	pwm[1-*]_enable		pwm[1-*]_enable
	Switch PWM on and off.		Switch PWM on and off.
	Not always present even if fan*_pwm is.		Not always present even if pwmN is.
	0: turn off		0: turn off
	1: turn on in manual mode		1: turn on in manual mode
	2+: turn on in automatic mode		2+: turn on in automatic mode
	Check individual chip documentation files for automatic mode details.		Check individual chip documentation files for automatic mode
			details.
	RW		RW

	pwm[1-*]_mode		pwm[1-*]_mode 0: DC mode (direct current)
	0: DC mode		1: PWM mode (pulse-width modulation)
	1: PWM mode		RW

			pwm[1-*]_freq Base PWM frequency in Hz.
			Only possibly available when pwmN_mode is PWM, but not always
			present even then.
	RW		RW

	pwm[1-*]_auto_channels_temp		pwm[1-*]_auto_channels_temp

drivers/hwmon/it87.c

+54 −2

Original line number	Original line	Diff line number	Diff line
	@@ -202,6 +202,17 @@ static int DIV_TO_REG(int val)
	}		}
	#define DIV_FROM_REG(val) (1 << (val))		#define DIV_FROM_REG(val) (1 << (val))

			static const unsigned int pwm_freq[8] = {
			48000000 / 128,
			24000000 / 128,
			12000000 / 128,
			8000000 / 128,
			6000000 / 128,
			3000000 / 128,
			1500000 / 128,
			750000 / 128,
			};


	/* For each registered IT87, we need to keep some data in memory. That		/* For each registered IT87, we need to keep some data in memory. That
	data is pointed to by it87_list[NR]->data. The structure itself is		data is pointed to by it87_list[NR]->data. The structure itself is
	@@ -232,6 +243,7 @@ struct it87_data {
	u8 vrm;		u8 vrm;
	u32 alarms; /* Register encoding, combined */		u32 alarms; /* Register encoding, combined */
	u8 fan_main_ctrl; /* Register value */		u8 fan_main_ctrl; /* Register value */
			u8 fan_ctl; /* Register value */
	u8 manual_pwm_ctl[3]; /* manual PWM value set by user */		u8 manual_pwm_ctl[3]; /* manual PWM value set by user */
	};		};

	@@ -519,6 +531,14 @@ static ssize_t show_pwm(struct device dev, struct device_attribute attr,
	struct it87_data *data = it87_update_device(dev);		struct it87_data *data = it87_update_device(dev);
	return sprintf(buf,"%d\n", data->manual_pwm_ctl[nr]);		return sprintf(buf,"%d\n", data->manual_pwm_ctl[nr]);
	}		}
			static ssize_t show_pwm_freq(struct device dev, struct device_attribute attr,
			char *buf)
			{
			struct it87_data *data = it87_update_device(dev);
			int index = (data->fan_ctl >> 4) & 0x07;

			return sprintf(buf, "%u\n", pwm_freq[index]);
			}
	static ssize_t set_fan_min(struct device dev, struct device_attribute attr,		static ssize_t set_fan_min(struct device dev, struct device_attribute attr,
	const char *buf, size_t count)		const char *buf, size_t count)
	{		{
	@@ -639,6 +659,28 @@ static ssize_t set_pwm(struct device dev, struct device_attribute attr,
	mutex_unlock(&data->update_lock);		mutex_unlock(&data->update_lock);
	return count;		return count;
	}		}
			static ssize_t set_pwm_freq(struct device *dev,
			struct device_attribute attr, const char buf, size_t count)
			{
			struct i2c_client *client = to_i2c_client(dev);
			struct it87_data *data = i2c_get_clientdata(client);
			unsigned long val = simple_strtoul(buf, NULL, 10);
			int i;

			/* Search for the nearest available frequency */
			for (i = 0; i < 7; i++) {
			if (val > (pwm_freq[i] + pwm_freq[i+1]) / 2)
			break;
			}

			mutex_lock(&data->update_lock);
			data->fan_ctl = it87_read_value(client, IT87_REG_FAN_CTL) & 0x8f;
			data->fan_ctl \|= i << 4;
			it87_write_value(client, IT87_REG_FAN_CTL, data->fan_ctl);
			mutex_unlock(&data->update_lock);

			return count;
			}

	#define show_fan_offset(offset) \		#define show_fan_offset(offset) \
	static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO, \		static SENSOR_DEVICE_ATTR(fan##offset##_input, S_IRUGO, \
	@@ -656,7 +698,10 @@ show_fan_offset(3);
	static SENSOR_DEVICE_ATTR(pwm##offset##_enable, S_IRUGO \| S_IWUSR, \		static SENSOR_DEVICE_ATTR(pwm##offset##_enable, S_IRUGO \| S_IWUSR, \
	show_pwm_enable, set_pwm_enable, offset - 1); \		show_pwm_enable, set_pwm_enable, offset - 1); \
	static SENSOR_DEVICE_ATTR(pwm##offset, S_IRUGO \| S_IWUSR, \		static SENSOR_DEVICE_ATTR(pwm##offset, S_IRUGO \| S_IWUSR, \
	show_pwm, set_pwm, offset - 1);		show_pwm, set_pwm, offset - 1); \
			static DEVICE_ATTR(pwm##offset##_freq, \
			(offset == 1 ? S_IRUGO \| S_IWUSR : S_IRUGO), \
			show_pwm_freq, (offset == 1 ? set_pwm_freq : NULL));

	show_pwm_offset(1);		show_pwm_offset(1);
	show_pwm_offset(2);		show_pwm_offset(2);
	@@ -1021,7 +1066,13 @@ static int it87_detect(struct i2c_adapter *adapter)
	\|\| (err = device_create_file(&new_client->dev,		\|\| (err = device_create_file(&new_client->dev,
	&sensor_dev_attr_pwm2.dev_attr))		&sensor_dev_attr_pwm2.dev_attr))
	\|\| (err = device_create_file(&new_client->dev,		\|\| (err = device_create_file(&new_client->dev,
	&sensor_dev_attr_pwm3.dev_attr)))		&sensor_dev_attr_pwm3.dev_attr))
			\|\| (err = device_create_file(&new_client->dev,
			&dev_attr_pwm1_freq))
			\|\| (err = device_create_file(&new_client->dev,
			&dev_attr_pwm2_freq))
			\|\| (err = device_create_file(&new_client->dev,
			&dev_attr_pwm3_freq)))
	goto ERROR4;		goto ERROR4;
	}		}

	@@ -1316,6 +1367,7 @@ static struct it87_data it87_update_device(struct device dev)
	(it87_read_value(client, IT87_REG_ALARM2) << 8) \|		(it87_read_value(client, IT87_REG_ALARM2) << 8) \|
	(it87_read_value(client, IT87_REG_ALARM3) << 16);		(it87_read_value(client, IT87_REG_ALARM3) << 16);
	data->fan_main_ctrl = it87_read_value(client, IT87_REG_FAN_MAIN_CTRL);		data->fan_main_ctrl = it87_read_value(client, IT87_REG_FAN_MAIN_CTRL);
			data->fan_ctl = it87_read_value(client, IT87_REG_FAN_CTL);

	data->sensor = it87_read_value(client, IT87_REG_TEMP_ENABLE);		data->sensor = it87_read_value(client, IT87_REG_TEMP_ENABLE);
	/* The 8705 does not have VID capability */		/* The 8705 does not have VID capability */