Commit 03508eea authored by Marc Ferland's avatar Marc Ferland Committed by Guenter Roeck
Browse files

hwmon: (mcp3021) improve driver support for newer hwmon interface 



This driver is currently broken, it does not show the in0_input sysfs
file and also returns the following message on startup:

hwmon_device_register() is deprecated. Please convert the driver to
use hwmon_device_register_with_info().

This patch converts the driver and also cleans up the 'read' function.

Signed-off-by: default avatarMarc Ferland <ferlandm@amotus.ca>
Link: https://lore.kernel.org/r/20220712193504.1374656-1-ferlandm@amotus.ca


Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent 9992b19d

drivers/hwmon/mcp3021.c

+49 −50
Original line number Diff line number Diff line
@@ -7,7 +7,7 @@ 
 * Reworked by Sven Schuchmann <schuchmann@schleissheimer.de>

 * DT support added by Clemens Gruber <clemens.gruber@pqgruber.com>

 *

 * This driver export the value of analog input voltage to sysfs, the

 * This driver exports the value of analog input voltage to sysfs, the

 * voltage unit is mV. Through the sysfs interface, lm-sensors tool

 * can also display the input voltage.

 */
@@ -45,19 +45,29 @@ enum chips { 
 * Client data (each client gets its own)

 */

struct mcp3021_data {

	struct device *hwmon_dev;

	struct i2c_client *client;

	u32 vdd;        /* supply and reference voltage in millivolt */

	u16 sar_shift;

	u16 sar_mask;

	u8 output_res;

};



static int mcp3021_read16(struct i2c_client *client)

static inline u16 volts_from_reg(struct mcp3021_data *data, u16 val)

{

	struct mcp3021_data *data = i2c_get_clientdata(client);

	int ret;

	u16 reg;

	return DIV_ROUND_CLOSEST(data->vdd * val, 1 << data->output_res);

}



static int mcp3021_read(struct device *dev, enum hwmon_sensor_types type,

			u32 attr, int channel, long *val)

{

	struct mcp3021_data *data = dev_get_drvdata(dev);

	struct i2c_client *client = data->client;

	__be16 buf;

	u16 reg;

	int ret;



	if (type != hwmon_in)

		return -EOPNOTSUPP;



	ret = i2c_master_recv(client, (char *)&buf, 2);

	if (ret < 0)
@@ -74,39 +84,46 @@ static int mcp3021_read16(struct i2c_client *client) 
	 */

	reg = (reg >> data->sar_shift) & data->sar_mask;



	return reg;

}

	*val = volts_from_reg(data, reg);



static inline u16 volts_from_reg(struct mcp3021_data *data, u16 val)

{

	return DIV_ROUND_CLOSEST(data->vdd * val, 1 << data->output_res);

	return 0;

}



static ssize_t in0_input_show(struct device *dev,

			      struct device_attribute *attr, char *buf)

static umode_t mcp3021_is_visible(const void *_data,

				  enum hwmon_sensor_types type,

				  u32 attr, int channel)

{

	struct i2c_client *client = to_i2c_client(dev);

	struct mcp3021_data *data = i2c_get_clientdata(client);

	int reg, in_input;



	reg = mcp3021_read16(client);

	if (reg < 0)

		return reg;

	if (type != hwmon_in)

		return 0;



	in_input = volts_from_reg(data, reg);

	if (attr != hwmon_in_input)

		return 0;



	return sprintf(buf, "%d\n", in_input);

	return 0444;

}



static DEVICE_ATTR_RO(in0_input);

static const struct hwmon_channel_info *mcp3021_info[] = {

	HWMON_CHANNEL_INFO(in, HWMON_I_INPUT),

	NULL

};



static const struct hwmon_ops mcp3021_hwmon_ops = {

	.is_visible = mcp3021_is_visible,

	.read = mcp3021_read,

};



static const struct hwmon_chip_info mcp3021_chip_info = {

	.ops = &mcp3021_hwmon_ops,

	.info = mcp3021_info,

};



static const struct i2c_device_id mcp3021_id[];



static int mcp3021_probe(struct i2c_client *client)

{

	int err;

	struct mcp3021_data *data = NULL;

	struct device_node *np = client->dev.of_node;

	struct device *hwmon_dev;



	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))

		return -ENODEV;
@@ -147,34 +164,17 @@ static int mcp3021_probe(struct i2c_client *client) 
		break;

	}



	data->client = client;



	if (data->vdd > MCP3021_VDD_REF_MAX || data->vdd < MCP3021_VDD_REF_MIN)

		return -EINVAL;



	err = sysfs_create_file(&client->dev.kobj, &dev_attr_in0_input.attr);

	if (err)

		return err;



	data->hwmon_dev = hwmon_device_register(&client->dev);

	if (IS_ERR(data->hwmon_dev)) {

		err = PTR_ERR(data->hwmon_dev);

		goto exit_remove;

	}



	return 0;



exit_remove:

	sysfs_remove_file(&client->dev.kobj, &dev_attr_in0_input.attr);

	return err;

}



static int mcp3021_remove(struct i2c_client *client)

{

	struct mcp3021_data *data = i2c_get_clientdata(client);



	hwmon_device_unregister(data->hwmon_dev);

	sysfs_remove_file(&client->dev.kobj, &dev_attr_in0_input.attr);



	return 0;

	hwmon_dev = devm_hwmon_device_register_with_info(&client->dev,

							 client->name,

							 data,

							 &mcp3021_chip_info,

							 NULL);

	return PTR_ERR_OR_ZERO(hwmon_dev);

}



static const struct i2c_device_id mcp3021_id[] = {
@@ -199,7 +199,6 @@ static struct i2c_driver mcp3021_driver = { 
		.of_match_table = of_match_ptr(of_mcp3021_match),

	},

	.probe_new = mcp3021_probe,

	.remove = mcp3021_remove,

	.id_table = mcp3021_id,

};