linux-stable/drivers/mfd/tps65911-comparator.c
Uwe Kleine-König 66d721ca1c mfd: tps65911-comparator: 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>
Link: https://lore.kernel.org/r/20231123165627.492259-18-u.kleine-koenig@pengutronix.de
Signed-off-by: Lee Jones <lee@kernel.org>
2023-12-07 13:50:28 +00:00

175 lines
4.2 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* tps65910.c -- TI TPS6591x
*
* Copyright 2010 Texas Instruments Inc.
*
* Author: Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/platform_device.h>
#include <linux/debugfs.h>
#include <linux/gpio.h>
#include <linux/mfd/tps65910.h>
#define COMP1 0
#define COMP2 1
/* Comparator 1 voltage selection table in millivolts */
static const u16 COMP_VSEL_TABLE[] = {
0, 2500, 2500, 2500, 2500, 2550, 2600, 2650,
2700, 2750, 2800, 2850, 2900, 2950, 3000, 3050,
3100, 3150, 3200, 3250, 3300, 3350, 3400, 3450,
3500,
};
struct comparator {
const char *name;
int reg;
int uV_max;
const u16 *vsel_table;
};
static struct comparator tps_comparators[] = {
{
.name = "COMP1",
.reg = TPS65911_VMBCH,
.uV_max = 3500,
.vsel_table = COMP_VSEL_TABLE,
},
{
.name = "COMP2",
.reg = TPS65911_VMBCH2,
.uV_max = 3500,
.vsel_table = COMP_VSEL_TABLE,
},
};
static int comp_threshold_set(struct tps65910 *tps65910, int id, int voltage)
{
struct comparator tps_comp = tps_comparators[id];
int curr_voltage = 0;
int ret;
u8 index = 0, val;
while (curr_voltage < tps_comp.uV_max) {
curr_voltage = tps_comp.vsel_table[index];
if (curr_voltage >= voltage)
break;
else if (curr_voltage < voltage)
index ++;
}
if (curr_voltage > tps_comp.uV_max)
return -EINVAL;
val = index << 1;
ret = regmap_write(tps65910->regmap, tps_comp.reg, val);
return ret;
}
static int comp_threshold_get(struct tps65910 *tps65910, int id)
{
struct comparator tps_comp = tps_comparators[id];
unsigned int val;
int ret;
ret = regmap_read(tps65910->regmap, tps_comp.reg, &val);
if (ret < 0)
return ret;
val >>= 1;
return tps_comp.vsel_table[val];
}
static ssize_t comp_threshold_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct tps65910 *tps65910 = dev_get_drvdata(dev->parent);
struct attribute comp_attr = attr->attr;
int id, uVolt;
if (!strcmp(comp_attr.name, "comp1_threshold"))
id = COMP1;
else if (!strcmp(comp_attr.name, "comp2_threshold"))
id = COMP2;
else
return -EINVAL;
uVolt = comp_threshold_get(tps65910, id);
return sprintf(buf, "%d\n", uVolt);
}
static DEVICE_ATTR(comp1_threshold, S_IRUGO, comp_threshold_show, NULL);
static DEVICE_ATTR(comp2_threshold, S_IRUGO, comp_threshold_show, NULL);
static int tps65911_comparator_probe(struct platform_device *pdev)
{
struct tps65910 *tps65910 = dev_get_drvdata(pdev->dev.parent);
struct tps65910_board *pdata = dev_get_platdata(tps65910->dev);
int ret;
ret = comp_threshold_set(tps65910, COMP1, pdata->vmbch_threshold);
if (ret < 0) {
dev_err(&pdev->dev, "cannot set COMP1 threshold\n");
return ret;
}
ret = comp_threshold_set(tps65910, COMP2, pdata->vmbch2_threshold);
if (ret < 0) {
dev_err(&pdev->dev, "cannot set COMP2 threshold\n");
return ret;
}
/* Create sysfs entry */
ret = device_create_file(&pdev->dev, &dev_attr_comp1_threshold);
if (ret < 0)
dev_err(&pdev->dev, "failed to add COMP1 sysfs file\n");
ret = device_create_file(&pdev->dev, &dev_attr_comp2_threshold);
if (ret < 0)
dev_err(&pdev->dev, "failed to add COMP2 sysfs file\n");
return ret;
}
static void tps65911_comparator_remove(struct platform_device *pdev)
{
struct tps65910 *tps65910;
tps65910 = dev_get_drvdata(pdev->dev.parent);
device_remove_file(&pdev->dev, &dev_attr_comp2_threshold);
device_remove_file(&pdev->dev, &dev_attr_comp1_threshold);
}
static struct platform_driver tps65911_comparator_driver = {
.driver = {
.name = "tps65911-comparator",
},
.probe = tps65911_comparator_probe,
.remove_new = tps65911_comparator_remove,
};
static int __init tps65911_comparator_init(void)
{
return platform_driver_register(&tps65911_comparator_driver);
}
subsys_initcall(tps65911_comparator_init);
static void __exit tps65911_comparator_exit(void)
{
platform_driver_unregister(&tps65911_comparator_driver);
}
module_exit(tps65911_comparator_exit);
MODULE_AUTHOR("Jorge Eduardo Candelaria <jedu@slimlogic.co.uk>");
MODULE_DESCRIPTION("TPS65911 comparator driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:tps65911-comparator");