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linuxdebug/drivers/iio/light/cm3605.c

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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 = dev_err_probe(dev, irq, "failed to get irq\n");
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 int 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);
return 0;
}
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 = 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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