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linux/drivers/iio/light/cm3605.c
Uwe Kleine-König 3e1e6787dc iio: light: cm3605: 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/20230919174931.1417681-37-u.kleine-koenig@pengutronix.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2023-09-23 15:06:55 +01:00

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// SPDX-License-Identifier: GPL-2.0-only
/*
* CM3605 Ambient Light and Proximity Sensor
*
* Copyright (C) 2016 Linaro Ltd.
* Author: Linus Walleij <linus.walleij@linaro.org>
*
* This hardware was found in the very first Nexus One handset from Google/HTC
* and an early endavour into mobile light and proximity sensors.
*/
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/iio/events.h>
#include <linux/iio/consumer.h> /* To get our ADC channel */
#include <linux/iio/types.h> /* To deal with our ADC channel */
#include <linux/init.h>
#include <linux/leds.h>
#include <linux/platform_device.h>
#include <linux/property.h>
#include <linux/regulator/consumer.h>
#include <linux/gpio/consumer.h>
#include <linux/interrupt.h>
#include <linux/math64.h>
#include <linux/pm.h>
#define CM3605_PROX_CHANNEL 0
#define CM3605_ALS_CHANNEL 1
#define CM3605_AOUT_TYP_MAX_MV 1550
/* It should not go above 1.650V according to the data sheet */
#define CM3605_AOUT_MAX_MV 1650
/**
* struct cm3605 - CM3605 state
* @dev: pointer to parent device
* @vdd: regulator controlling VDD
* @aset: sleep enable GPIO, high = sleep
* @aout: IIO ADC channel to convert the AOUT signal
* @als_max: maximum LUX detection (depends on RSET)
* @dir: proximity direction: start as FALLING
* @led: trigger for the infrared LED used by the proximity sensor
*/
struct cm3605 {
struct device *dev;
struct regulator *vdd;
struct gpio_desc *aset;
struct iio_channel *aout;
s32 als_max;
enum iio_event_direction dir;
struct led_trigger *led;
};
static irqreturn_t cm3605_prox_irq(int irq, void *d)
{
struct iio_dev *indio_dev = d;
struct cm3605 *cm3605 = iio_priv(indio_dev);
u64 ev;
ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, CM3605_PROX_CHANNEL,
IIO_EV_TYPE_THRESH, cm3605->dir);
iio_push_event(indio_dev, ev, iio_get_time_ns(indio_dev));
/* Invert the edge for each event */
if (cm3605->dir == IIO_EV_DIR_RISING)
cm3605->dir = IIO_EV_DIR_FALLING;
else
cm3605->dir = IIO_EV_DIR_RISING;
return IRQ_HANDLED;
}
static int cm3605_get_lux(struct cm3605 *cm3605)
{
int ret, res;
s64 lux;
ret = iio_read_channel_processed(cm3605->aout, &res);
if (ret < 0)
return ret;
dev_dbg(cm3605->dev, "read %d mV from ADC\n", res);
/*
* AOUT has an offset of ~30mV then linear at dark
* then goes from 2.54 up to 650 LUX yielding 1.55V
* (1550 mV) so scale the returned value to this interval
* using simple linear interpolation.
*/
if (res < 30)
return 0;
if (res > CM3605_AOUT_MAX_MV)
dev_err(cm3605->dev, "device out of range\n");
/* Remove bias */
lux = res - 30;
/* Linear interpolation between 0 and ALS typ max */
lux *= cm3605->als_max;
lux = div64_s64(lux, CM3605_AOUT_TYP_MAX_MV);
return lux;
}
static int cm3605_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct cm3605 *cm3605 = iio_priv(indio_dev);
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (chan->type) {
case IIO_LIGHT:
ret = cm3605_get_lux(cm3605);
if (ret < 0)
return ret;
*val = ret;
return IIO_VAL_INT;
default:
return -EINVAL;
}
default:
return -EINVAL;
}
}
static const struct iio_info cm3605_info = {
.read_raw = cm3605_read_raw,
};
static const struct iio_event_spec cm3605_events[] = {
{
.type = IIO_EV_TYPE_THRESH,
.dir = IIO_EV_DIR_EITHER,
.mask_separate = BIT(IIO_EV_INFO_ENABLE),
},
};
static const struct iio_chan_spec cm3605_channels[] = {
{
.type = IIO_PROXIMITY,
.event_spec = cm3605_events,
.num_event_specs = ARRAY_SIZE(cm3605_events),
},
{
.type = IIO_LIGHT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
.channel = CM3605_ALS_CHANNEL,
},
};
static int cm3605_probe(struct platform_device *pdev)
{
struct cm3605 *cm3605;
struct iio_dev *indio_dev;
struct device *dev = &pdev->dev;
enum iio_chan_type ch_type;
u32 rset;
int irq;
int ret;
indio_dev = devm_iio_device_alloc(dev, sizeof(*cm3605));
if (!indio_dev)
return -ENOMEM;
platform_set_drvdata(pdev, indio_dev);
cm3605 = iio_priv(indio_dev);
cm3605->dev = dev;
cm3605->dir = IIO_EV_DIR_FALLING;
ret = device_property_read_u32(dev, "capella,aset-resistance-ohms", &rset);
if (ret) {
dev_info(dev, "no RSET specified, assuming 100K\n");
rset = 100000;
}
switch (rset) {
case 50000:
cm3605->als_max = 650;
break;
case 100000:
cm3605->als_max = 300;
break;
case 300000:
cm3605->als_max = 100;
break;
case 600000:
cm3605->als_max = 50;
break;
default:
dev_info(dev, "non-standard resistance\n");
return -EINVAL;
}
cm3605->aout = devm_iio_channel_get(dev, "aout");
if (IS_ERR(cm3605->aout)) {
ret = PTR_ERR(cm3605->aout);
ret = (ret == -ENODEV) ? -EPROBE_DEFER : ret;
return dev_err_probe(dev, ret, "failed to get AOUT ADC channel\n");
}
ret = iio_get_channel_type(cm3605->aout, &ch_type);
if (ret < 0)
return ret;
if (ch_type != IIO_VOLTAGE) {
dev_err(dev, "wrong type of IIO channel specified for AOUT\n");
return -EINVAL;
}
cm3605->vdd = devm_regulator_get(dev, "vdd");
if (IS_ERR(cm3605->vdd))
return dev_err_probe(dev, PTR_ERR(cm3605->vdd),
"failed to get VDD regulator\n");
ret = regulator_enable(cm3605->vdd);
if (ret) {
dev_err(dev, "failed to enable VDD regulator\n");
return ret;
}
cm3605->aset = devm_gpiod_get(dev, "aset", GPIOD_OUT_HIGH);
if (IS_ERR(cm3605->aset)) {
ret = dev_err_probe(dev, PTR_ERR(cm3605->aset), "no ASET GPIO\n");
goto out_disable_vdd;
}
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
ret = irq;
goto out_disable_aset;
}
ret = devm_request_threaded_irq(dev, irq, cm3605_prox_irq,
NULL, 0, "cm3605", indio_dev);
if (ret) {
dev_err(dev, "unable to request IRQ\n");
goto out_disable_aset;
}
/* Just name the trigger the same as the driver */
led_trigger_register_simple("cm3605", &cm3605->led);
led_trigger_event(cm3605->led, LED_FULL);
indio_dev->info = &cm3605_info;
indio_dev->name = "cm3605";
indio_dev->channels = cm3605_channels;
indio_dev->num_channels = ARRAY_SIZE(cm3605_channels);
indio_dev->modes = INDIO_DIRECT_MODE;
ret = iio_device_register(indio_dev);
if (ret)
goto out_remove_trigger;
dev_info(dev, "Capella Microsystems CM3605 enabled range 0..%d LUX\n",
cm3605->als_max);
return 0;
out_remove_trigger:
led_trigger_event(cm3605->led, LED_OFF);
led_trigger_unregister_simple(cm3605->led);
out_disable_aset:
gpiod_set_value_cansleep(cm3605->aset, 0);
out_disable_vdd:
regulator_disable(cm3605->vdd);
return ret;
}
static void cm3605_remove(struct platform_device *pdev)
{
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
struct cm3605 *cm3605 = iio_priv(indio_dev);
led_trigger_event(cm3605->led, LED_OFF);
led_trigger_unregister_simple(cm3605->led);
gpiod_set_value_cansleep(cm3605->aset, 0);
iio_device_unregister(indio_dev);
regulator_disable(cm3605->vdd);
}
static int cm3605_pm_suspend(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct cm3605 *cm3605 = iio_priv(indio_dev);
led_trigger_event(cm3605->led, LED_OFF);
regulator_disable(cm3605->vdd);
return 0;
}
static int cm3605_pm_resume(struct device *dev)
{
struct iio_dev *indio_dev = dev_get_drvdata(dev);
struct cm3605 *cm3605 = iio_priv(indio_dev);
int ret;
ret = regulator_enable(cm3605->vdd);
if (ret)
dev_err(dev, "failed to enable regulator in resume path\n");
led_trigger_event(cm3605->led, LED_FULL);
return 0;
}
static DEFINE_SIMPLE_DEV_PM_OPS(cm3605_dev_pm_ops, cm3605_pm_suspend,
cm3605_pm_resume);
static const struct of_device_id cm3605_of_match[] = {
{.compatible = "capella,cm3605"},
{ },
};
MODULE_DEVICE_TABLE(of, cm3605_of_match);
static struct platform_driver cm3605_driver = {
.driver = {
.name = "cm3605",
.of_match_table = cm3605_of_match,
.pm = pm_sleep_ptr(&cm3605_dev_pm_ops),
},
.probe = cm3605_probe,
.remove_new = cm3605_remove,
};
module_platform_driver(cm3605_driver);
MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
MODULE_DESCRIPTION("CM3605 ambient light and proximity sensor driver");
MODULE_LICENSE("GPL");
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