Commit 2ed4db7a authored by Florin Leotescu's avatar Florin Leotescu Committed by Guenter Roeck
Browse files

hwmon: (emc2305) Configure PWM channels based on DT properties 



Add support for configuring each PWM channel using Device Tree (DT)
properties by parsing the 'pwms' phandle arguments.

Signed-off-by: default avatarFlorin Leotescu <florin.leotescu@nxp.com>
Link: https://lore.kernel.org/r/20250603113125.3175103-3-florin.leotescu@oss.nxp.com


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 7114b74d

drivers/hwmon/emc2305.c

+129 −22
Original line number Diff line number Diff line
@@ -11,6 +11,9 @@ 
#include <linux/module.h>

#include <linux/platform_data/emc2305.h>

#include <linux/thermal.h>

#include <linux/pwm.h>

#include <linux/of_device.h>

#include <linux/util_macros.h>



#define EMC2305_REG_DRIVE_FAIL_STATUS	0x27

#define EMC2305_REG_VENDOR		0xfe
@@ -23,6 +26,8 @@ 
#define EMC2305_TACH_REGS_UNUSE_BITS	3

#define EMC2305_TACH_CNT_MULTIPLIER	0x02

#define EMC2305_TACH_RANGE_MIN		480

#define EMC2305_DEFAULT_OUTPUT		0x0

#define EMC2305_DEFAULT_POLARITY	0x0



#define EMC2305_PWM_DUTY2STATE(duty, max_state, pwm_max) \

	DIV_ROUND_CLOSEST((duty) * (max_state), (pwm_max))
@@ -39,6 +44,9 @@ 
#define EMC2305_REG_FAN_MIN_DRIVE(n)	(0x38 + 0x10 * (n))

#define EMC2305_REG_FAN_TACH(n)		(0x3e + 0x10 * (n))



/* Supported base PWM frequencies */

static const unsigned int base_freq_table[] = { 2441, 4882, 19530, 26000 };



enum emc230x_product_id {

	EMC2305 = 0x34,

	EMC2303 = 0x35,
@@ -287,7 +295,7 @@ static int emc2305_set_pwm(struct device *dev, long val, int channel) 
	return 0;

}



static int emc2305_set_single_tz(struct device *dev, int idx)

static int emc2305_set_single_tz(struct device *dev, struct device_node *fan_node, int idx)

{

	struct emc2305_data *data = dev_get_drvdata(dev);

	long pwm;
@@ -297,7 +305,7 @@ static int emc2305_set_single_tz(struct device *dev, int idx) 
	pwm = data->pwm_min[cdev_idx];



	data->cdev_data[cdev_idx].cdev =

		devm_thermal_of_cooling_device_register(dev, dev->of_node,

		devm_thermal_of_cooling_device_register(dev, fan_node,

							emc2305_fan_name[idx], data,

							&emc2305_cooling_ops);
@@ -332,10 +340,10 @@ static int emc2305_set_tz(struct device *dev) 
	int i, ret;



	if (!data->pwm_separate)

		return emc2305_set_single_tz(dev, 0);

		return emc2305_set_single_tz(dev, dev->of_node, 0);



	for (i = 0; i < data->pwm_num; i++) {

		ret = emc2305_set_single_tz(dev, i + 1);

		ret = emc2305_set_single_tz(dev, dev->of_node, i + 1);

		if (ret)

			return ret;

	}
@@ -517,15 +525,85 @@ static int emc2305_identify(struct device *dev) 
	return 0;

}



static int emc2305_of_parse_pwm_child(struct device *dev,

				      struct device_node *child,

				      struct emc2305_data *data)

{	u32 ch;

	int ret;

	struct of_phandle_args args;



	ret = of_property_read_u32(child, "reg", &ch);

	if (ret) {

		dev_err(dev, "missing reg property of %pOFn\n", child);

		return ret;

	}



	ret = of_parse_phandle_with_args(child, "pwms", "#pwm-cells", 0, &args);



	if (ret)

		return ret;



	if (args.args_count > 0) {

		data->pwm_freq[ch] = find_closest(args.args[0], base_freq_table,

						  ARRAY_SIZE(base_freq_table));

	} else {

		data->pwm_freq[ch] = base_freq_table[3];

	}



	if (args.args_count > 1) {

		if (args.args[1] == PWM_POLARITY_NORMAL || args.args[1] == PWM_POLARITY_INVERSED)

			data->pwm_polarity_mask |= args.args[1] << ch;

		else

			dev_err(dev, "Wrong PWM polarity config provided: %d\n", args.args[0]);

	} else {

		data->pwm_polarity_mask |= PWM_POLARITY_NORMAL << ch;

	}



	if (args.args_count > 2) {

		if (args.args[2] == EMC2305_PUSH_PULL || args.args[2] <= EMC2305_OPEN_DRAIN)

			data->pwm_output_mask |= args.args[2] << ch;

		else

			dev_err(dev, "Wrong PWM output config provided: %d\n", args.args[1]);

	} else {

		data->pwm_output_mask |= EMC2305_OPEN_DRAIN << ch;

	}



	return 0;

}



static int emc2305_probe_childs_from_dt(struct device *dev)

{

	struct emc2305_data *data = dev_get_drvdata(dev);

	struct device_node *child;

	int ret, count = 0;



	data->pwm_output_mask = 0x0;

	data->pwm_polarity_mask = 0x0;



	for_each_child_of_node(dev->of_node, child) {

		if (of_property_present(child, "reg")) {

			ret = emc2305_of_parse_pwm_child(dev, child, data);

			if (ret) {

				of_node_put(child);

				continue;

			}

			count++;

		}

	}

	return count;

}



static int emc2305_probe(struct i2c_client *client)

{

	struct i2c_adapter *adapter = client->adapter;

	struct device *dev = &client->dev;

	struct device_node *child;

	struct emc2305_data *data;

	struct emc2305_platform_data *pdata;

	int vendor;

	int ret;

	int i;

	int pwm_childs;



	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_WORD_DATA))

		return -ENODEV;
@@ -545,7 +623,11 @@ static int emc2305_probe(struct i2c_client *client) 
	if (ret)

		return ret;



	pwm_childs = emc2305_probe_childs_from_dt(dev);



	pdata = dev_get_platdata(&client->dev);



	if (!pwm_childs) {

		if (pdata) {

			if (!pdata->max_state || pdata->max_state > EMC2305_FAN_MAX_STATE)

				return -EINVAL;
@@ -558,9 +640,23 @@ static int emc2305_probe(struct i2c_client *client) 
			if (!pdata->pwm_num || pdata->pwm_num > EMC2305_PWM_MAX)

				return -EINVAL;

			data->pwm_num = pdata->pwm_num;

			data->pwm_output_mask = pdata->pwm_output_mask;

			data->pwm_polarity_mask = pdata->pwm_polarity_mask;

			data->pwm_separate = pdata->pwm_separate;

		for (i = 0; i < EMC2305_PWM_MAX; i++)

			for (i = 0; i < EMC2305_PWM_MAX; i++) {

				data->pwm_min[i] = pdata->pwm_min[i];

				data->pwm_freq[i] = pdata->pwm_freq[i];

			}

		} else {

			data->max_state = EMC2305_FAN_MAX_STATE;

			data->pwm_separate = false;

			data->pwm_output_mask = EMC2305_DEFAULT_OUTPUT;

			data->pwm_polarity_mask = EMC2305_DEFAULT_POLARITY;

			for (i = 0; i < EMC2305_PWM_MAX; i++) {

				data->pwm_min[i] = EMC2305_FAN_MIN;

				data->pwm_freq[i] = base_freq_table[3];

			}

		}

	} else {

		data->max_state = EMC2305_FAN_MAX_STATE;

		data->pwm_separate = false;
@@ -574,10 +670,21 @@ static int emc2305_probe(struct i2c_client *client) 
		return PTR_ERR(data->hwmon_dev);



	if (IS_REACHABLE(CONFIG_THERMAL)) {

		/* Parse and check for the available PWM child nodes */

		if (pwm_childs > 0) {

			i = 0;

			for_each_child_of_node(dev->of_node, child) {

				ret = emc2305_set_single_tz(dev, child, i);

				if (ret != 0)

					return ret;

				i++;

			}

		} else {

			ret = emc2305_set_tz(dev);

			if (ret != 0)

				return ret;

		}

	}



	for (i = 0; i < data->pwm_num; i++) {

		ret = i2c_smbus_write_byte_data(client, EMC2305_REG_FAN_MIN_DRIVE(i),