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linux/drivers/hwmon/mc13783-adc.c
Uwe Kleine-König 13af7eeeb6 hwmon: (mc13783-adc) Convert to platform remove callback returning void 
The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is ignored (apart
from emitting a warning) and this typically results in resource leaks.
To improve here there is a quest to make the remove callback return
void. In the first step of this quest all drivers are converted to
.remove_new() which already returns void. Eventually after all drivers
are converted, .remove_new() is renamed to .remove().

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230918085951.1234172-11-u.kleine-koenig@pengutronix.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2023-10-27 07:27:24 -07:00

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// SPDX-License-Identifier: GPL-2.0+
/*
* Driver for the ADC on Freescale Semiconductor MC13783 and MC13892 PMICs.
*
* Copyright 2004-2007 Freescale Semiconductor, Inc. All Rights Reserved.
* Copyright (C) 2009 Sascha Hauer, Pengutronix
*/
#include <linux/mfd/mc13xxx.h>
#include <linux/platform_device.h>
#include <linux/hwmon-sysfs.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/hwmon.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/err.h>
#define DRIVER_NAME "mc13783-adc"
/* platform device id driver data */
#define MC13783_ADC_16CHANS 1
#define MC13783_ADC_BPDIV2 2
struct mc13783_adc_priv {
struct mc13xxx *mc13xxx;
struct device *hwmon_dev;
char name[PLATFORM_NAME_SIZE];
};
static ssize_t name_show(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct mc13783_adc_priv *priv = dev_get_drvdata(dev);
return sprintf(buf, "%s\n", priv->name);
}
static int mc13783_adc_read(struct device *dev,
struct device_attribute *devattr, unsigned int *val)
{
struct mc13783_adc_priv *priv = dev_get_drvdata(dev);
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
unsigned int channel = attr->index;
unsigned int sample[4];
int ret;
ret = mc13xxx_adc_do_conversion(priv->mc13xxx,
MC13XXX_ADC_MODE_MULT_CHAN,
channel, 0, 0, sample);
if (ret)
return ret;
/* ADIN7 subchannels */
if (channel >= 16)
channel = 7;
channel &= 0x7;
*val = (sample[channel % 4] >> (channel > 3 ? 14 : 2)) & 0x3ff;
return 0;
}
static ssize_t mc13783_adc_bp_show(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
unsigned val;
struct platform_device *pdev = to_platform_device(dev);
kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
int ret = mc13783_adc_read(dev, devattr, &val);
if (ret)
return ret;
if (driver_data & MC13783_ADC_BPDIV2)
val = DIV_ROUND_CLOSEST(val * 9, 2);
else
/*
* BP (channel 2) reports with offset 2.4V to the actual value
* to fit the input range of the ADC. unit = 2.25mV = 9/4 mV.
*/
val = DIV_ROUND_CLOSEST(val * 9, 4) + 2400;
return sprintf(buf, "%u\n", val);
}
static ssize_t mc13783_adc_gp_show(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
unsigned val;
int ret = mc13783_adc_read(dev, devattr, &val);
if (ret)
return ret;
/*
* input range is [0, 2.3V], val has 10 bits, so each bit
* is worth 9/4 mV.
*/
val = DIV_ROUND_CLOSEST(val * 9, 4);
return sprintf(buf, "%u\n", val);
}
static ssize_t mc13783_adc_uid_show(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
unsigned int val;
struct platform_device *pdev = to_platform_device(dev);
kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
int ret = mc13783_adc_read(dev, devattr, &val);
if (ret)
return ret;
if (driver_data & MC13783_ADC_BPDIV2)
/* MC13892 have 1/2 divider, input range is [0, 4.800V] */
val = DIV_ROUND_CLOSEST(val * 4800, 1024);
else
/* MC13783 have 0.9 divider, input range is [0, 2.555V] */
val = DIV_ROUND_CLOSEST(val * 2555, 1024);
return sprintf(buf, "%u\n", val);
}
static ssize_t mc13783_adc_temp_show(struct device *dev,
struct device_attribute *devattr,
char *buf)
{
unsigned int val;
struct platform_device *pdev = to_platform_device(dev);
kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
int ret = mc13783_adc_read(dev, devattr, &val);
if (ret)
return ret;
if (driver_data & MC13783_ADC_BPDIV2) {
/*
* MC13892:
* Die Temperature Read Out Code at 25C 680
* Temperature change per LSB +0.4244C
*/
ret = DIV_ROUND_CLOSEST(-2635920 + val * 4244, 10);
} else {
/*
* MC13783:
* Die Temperature Read Out Code at 25C 282
* Temperature change per LSB -1.14C
*/
ret = 346480 - 1140 * val;
}
return sprintf(buf, "%d\n", ret);
}
static DEVICE_ATTR_RO(name);
static SENSOR_DEVICE_ATTR_RO(in2_input, mc13783_adc_bp, 2);
static SENSOR_DEVICE_ATTR_RO(in5_input, mc13783_adc_gp, 5);
static SENSOR_DEVICE_ATTR_RO(in6_input, mc13783_adc_gp, 6);
static SENSOR_DEVICE_ATTR_RO(in7_input, mc13783_adc_gp, 7);
static SENSOR_DEVICE_ATTR_RO(in8_input, mc13783_adc_gp, 8);
static SENSOR_DEVICE_ATTR_RO(in9_input, mc13783_adc_gp, 9);
static SENSOR_DEVICE_ATTR_RO(in10_input, mc13783_adc_gp, 10);
static SENSOR_DEVICE_ATTR_RO(in11_input, mc13783_adc_gp, 11);
static SENSOR_DEVICE_ATTR_RO(in12_input, mc13783_adc_gp, 12);
static SENSOR_DEVICE_ATTR_RO(in13_input, mc13783_adc_gp, 13);
static SENSOR_DEVICE_ATTR_RO(in14_input, mc13783_adc_gp, 14);
static SENSOR_DEVICE_ATTR_RO(in15_input, mc13783_adc_gp, 15);
static SENSOR_DEVICE_ATTR_RO(in16_input, mc13783_adc_uid, 16);
static SENSOR_DEVICE_ATTR_RO(temp1_input, mc13783_adc_temp, 17);
static struct attribute *mc13783_attr_base[] = {
&dev_attr_name.attr,
&sensor_dev_attr_in2_input.dev_attr.attr,
&sensor_dev_attr_in5_input.dev_attr.attr,
&sensor_dev_attr_in6_input.dev_attr.attr,
&sensor_dev_attr_in7_input.dev_attr.attr,
&sensor_dev_attr_in16_input.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
NULL
};
static const struct attribute_group mc13783_group_base = {
.attrs = mc13783_attr_base,
};
/* these are only used if MC13783_ADC_16CHANS is provided in driver data */
static struct attribute *mc13783_attr_16chans[] = {
&sensor_dev_attr_in8_input.dev_attr.attr,
&sensor_dev_attr_in9_input.dev_attr.attr,
&sensor_dev_attr_in10_input.dev_attr.attr,
&sensor_dev_attr_in11_input.dev_attr.attr,
NULL
};
static const struct attribute_group mc13783_group_16chans = {
.attrs = mc13783_attr_16chans,
};
/* last four channels may be occupied by the touchscreen */
static struct attribute *mc13783_attr_ts[] = {
&sensor_dev_attr_in12_input.dev_attr.attr,
&sensor_dev_attr_in13_input.dev_attr.attr,
&sensor_dev_attr_in14_input.dev_attr.attr,
&sensor_dev_attr_in15_input.dev_attr.attr,
NULL
};
static const struct attribute_group mc13783_group_ts = {
.attrs = mc13783_attr_ts,
};
static int mc13783_adc_use_touchscreen(struct platform_device *pdev)
{
struct mc13783_adc_priv *priv = platform_get_drvdata(pdev);
unsigned flags = mc13xxx_get_flags(priv->mc13xxx);
return flags & MC13XXX_USE_TOUCHSCREEN;
}
static int __init mc13783_adc_probe(struct platform_device *pdev)
{
struct mc13783_adc_priv *priv;
int ret;
const struct platform_device_id *id = platform_get_device_id(pdev);
char *dash;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->mc13xxx = dev_get_drvdata(pdev->dev.parent);
snprintf(priv->name, ARRAY_SIZE(priv->name), "%s", id->name);
dash = strchr(priv->name, '-');
if (dash)
*dash = '\0';
platform_set_drvdata(pdev, priv);
/* Register sysfs hooks */
ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_base);
if (ret)
return ret;
if (id->driver_data & MC13783_ADC_16CHANS) {
ret = sysfs_create_group(&pdev->dev.kobj,
&mc13783_group_16chans);
if (ret)
goto out_err_create_16chans;
}
if (!mc13783_adc_use_touchscreen(pdev)) {
ret = sysfs_create_group(&pdev->dev.kobj, &mc13783_group_ts);
if (ret)
goto out_err_create_ts;
}
priv->hwmon_dev = hwmon_device_register(&pdev->dev);
if (IS_ERR(priv->hwmon_dev)) {
ret = PTR_ERR(priv->hwmon_dev);
dev_err(&pdev->dev,
"hwmon_device_register failed with %d.\n", ret);
goto out_err_register;
}
return 0;
out_err_register:
if (!mc13783_adc_use_touchscreen(pdev))
sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts);
out_err_create_ts:
if (id->driver_data & MC13783_ADC_16CHANS)
sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans);
out_err_create_16chans:
sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base);
return ret;
}
static void mc13783_adc_remove(struct platform_device *pdev)
{
struct mc13783_adc_priv *priv = platform_get_drvdata(pdev);
kernel_ulong_t driver_data = platform_get_device_id(pdev)->driver_data;
hwmon_device_unregister(priv->hwmon_dev);
if (!mc13783_adc_use_touchscreen(pdev))
sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_ts);
if (driver_data & MC13783_ADC_16CHANS)
sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_16chans);
sysfs_remove_group(&pdev->dev.kobj, &mc13783_group_base);
}
static const struct platform_device_id mc13783_adc_idtable[] = {
{
.name = "mc13783-adc",
.driver_data = MC13783_ADC_16CHANS,
}, {
.name = "mc13892-adc",
.driver_data = MC13783_ADC_BPDIV2,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(platform, mc13783_adc_idtable);
static struct platform_driver mc13783_adc_driver = {
.remove_new = mc13783_adc_remove,
.driver = {
.name = DRIVER_NAME,
},
.id_table = mc13783_adc_idtable,
};
module_platform_driver_probe(mc13783_adc_driver, mc13783_adc_probe);
MODULE_DESCRIPTION("MC13783 ADC driver");
MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
MODULE_LICENSE("GPL");
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