Commit f4dc811c authored by Clemens Gruber's avatar Clemens Gruber Committed by Guenter Roeck
Browse files

hwmon: (mcp3021) add devicetree support 



Support setting the reference voltage from the device tree.

Signed-off-by: default avatarClemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: default avatarGuenter Roeck <linux@roeck-us.net>
parent b502a926

drivers/hwmon/mcp3021.c

+36 −12
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
 * Copyright (C) 2008-2009, 2012 Freescale Semiconductor, Inc.

 * Author: Mingkai Hu <Mingkai.hu@freescale.com>

 * 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

 * voltage unit is mV. Through the sysfs interface, lm-sensors tool
@@ -22,11 +23,13 @@ 
#include <linux/i2c.h>

#include <linux/err.h>

#include <linux/device.h>

#include <linux/of.h>

#include <linux/of_device.h>



/* Vdd info */

#define MCP3021_VDD_MAX		5500

#define MCP3021_VDD_MIN		2700

#define MCP3021_VDD_REF		3300

/* Vdd / reference voltage in millivolt */

#define MCP3021_VDD_REF_MAX	5500

#define MCP3021_VDD_REF_MIN	2700

#define MCP3021_VDD_REF_DEFAULT	3300



/* output format */

#define MCP3021_SAR_SHIFT	2
@@ -47,7 +50,7 @@ enum chips { 
 */

struct mcp3021_data {

	struct device *hwmon_dev;

	u32 vdd;	/* device power supply */

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

	u16 sar_shift;

	u16 sar_mask;

	u8 output_res;
@@ -106,6 +109,7 @@ static int mcp3021_probe(struct i2c_client *client, 
{

	int err;

	struct mcp3021_data *data = NULL;

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



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

		return -ENODEV;
@@ -117,6 +121,21 @@ static int mcp3021_probe(struct i2c_client *client, 


	i2c_set_clientdata(client, data);



	if (np) {

		if (!of_property_read_u32(np, "reference-voltage-microvolt",

					  &data->vdd))

			data->vdd /= 1000;

		else

			data->vdd = MCP3021_VDD_REF_DEFAULT;

	} else {

		u32 *pdata = dev_get_platdata(&client->dev);



		if (pdata)

			data->vdd = *pdata;

		else

			data->vdd = MCP3021_VDD_REF_DEFAULT;

	}



	switch (id->driver_data) {

	case mcp3021:

		data->sar_shift = MCP3021_SAR_SHIFT;
@@ -131,13 +150,8 @@ static int mcp3021_probe(struct i2c_client *client, 
		break;

	}



	if (dev_get_platdata(&client->dev)) {

		data->vdd = *(u32 *)dev_get_platdata(&client->dev);

		if (data->vdd > MCP3021_VDD_MAX || data->vdd < MCP3021_VDD_MIN)

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

		return -EINVAL;

	} else {

		data->vdd = MCP3021_VDD_REF;

	}



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

	if (err)
@@ -173,9 +187,19 @@ static const struct i2c_device_id mcp3021_id[] = { 
};

MODULE_DEVICE_TABLE(i2c, mcp3021_id);



#ifdef CONFIG_OF

static const struct of_device_id of_mcp3021_match[] = {

	{ .compatible = "microchip,mcp3021", .data = (void *)mcp3021 },

	{ .compatible = "microchip,mcp3221", .data = (void *)mcp3221 },

	{ }

};

MODULE_DEVICE_TABLE(of, of_mcp3021_match);

#endif



static struct i2c_driver mcp3021_driver = {

	.driver = {

		.name = "mcp3021",

		.of_match_table = of_match_ptr(of_mcp3021_match),

	},

	.probe = mcp3021_probe,

	.remove = mcp3021_remove,