linux/drivers/thermal/kirkwood_thermal.c
Uwe Kleine-König 3ebaf0f244 thermal: kirkwood: 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() will be 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>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-09-29 12:34:17 +02:00

117 lines
2.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Kirkwood thermal sensor driver
*
* Copyright (C) 2012 Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
*/
#include <linux/device.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/of.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/thermal.h>
#define KIRKWOOD_THERMAL_VALID_OFFSET 9
#define KIRKWOOD_THERMAL_VALID_MASK 0x1
#define KIRKWOOD_THERMAL_TEMP_OFFSET 10
#define KIRKWOOD_THERMAL_TEMP_MASK 0x1FF
/* Kirkwood Thermal Sensor Dev Structure */
struct kirkwood_thermal_priv {
void __iomem *sensor;
};
static int kirkwood_get_temp(struct thermal_zone_device *thermal,
int *temp)
{
unsigned long reg;
struct kirkwood_thermal_priv *priv = thermal_zone_device_priv(thermal);
reg = readl_relaxed(priv->sensor);
/* Valid check */
if (!((reg >> KIRKWOOD_THERMAL_VALID_OFFSET) &
KIRKWOOD_THERMAL_VALID_MASK))
return -EIO;
/*
* Calculate temperature. According to Marvell internal
* documentation the formula for this is:
* Celsius = (322-reg)/1.3625
*/
reg = (reg >> KIRKWOOD_THERMAL_TEMP_OFFSET) &
KIRKWOOD_THERMAL_TEMP_MASK;
*temp = ((3220000000UL - (10000000UL * reg)) / 13625);
return 0;
}
static struct thermal_zone_device_ops ops = {
.get_temp = kirkwood_get_temp,
};
static const struct of_device_id kirkwood_thermal_id_table[] = {
{ .compatible = "marvell,kirkwood-thermal" },
{}
};
static int kirkwood_thermal_probe(struct platform_device *pdev)
{
struct thermal_zone_device *thermal = NULL;
struct kirkwood_thermal_priv *priv;
int ret;
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->sensor = devm_platform_get_and_ioremap_resource(pdev, 0, NULL);
if (IS_ERR(priv->sensor))
return PTR_ERR(priv->sensor);
thermal = thermal_tripless_zone_device_register("kirkwood_thermal",
priv, &ops, NULL);
if (IS_ERR(thermal)) {
dev_err(&pdev->dev,
"Failed to register thermal zone device\n");
return PTR_ERR(thermal);
}
ret = thermal_zone_device_enable(thermal);
if (ret) {
thermal_zone_device_unregister(thermal);
dev_err(&pdev->dev, "Failed to enable thermal zone device\n");
return ret;
}
platform_set_drvdata(pdev, thermal);
return 0;
}
static void kirkwood_thermal_exit(struct platform_device *pdev)
{
struct thermal_zone_device *kirkwood_thermal =
platform_get_drvdata(pdev);
thermal_zone_device_unregister(kirkwood_thermal);
}
MODULE_DEVICE_TABLE(of, kirkwood_thermal_id_table);
static struct platform_driver kirkwood_thermal_driver = {
.probe = kirkwood_thermal_probe,
.remove_new = kirkwood_thermal_exit,
.driver = {
.name = "kirkwood_thermal",
.of_match_table = kirkwood_thermal_id_table,
},
};
module_platform_driver(kirkwood_thermal_driver);
MODULE_AUTHOR("Nobuhiro Iwamatsu <iwamatsu@nigauri.org>");
MODULE_DESCRIPTION("kirkwood thermal driver");
MODULE_LICENSE("GPL");