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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * CM3605 Ambient Light and Proximity Sensor4 *5 * Copyright (C) 2016 Linaro Ltd.6 * Author: Linus Walleij <linus.walleij@linaro.org>7 *8 * This hardware was found in the very first Nexus One handset from Google/HTC9 * and an early endavour into mobile light and proximity sensors.10 */11 12#include <linux/module.h>13#include <linux/mod_devicetable.h>14#include <linux/iio/iio.h>15#include <linux/iio/sysfs.h>16#include <linux/iio/events.h>17#include <linux/iio/consumer.h> /* To get our ADC channel */18#include <linux/iio/types.h> /* To deal with our ADC channel */19#include <linux/init.h>20#include <linux/leds.h>21#include <linux/platform_device.h>22#include <linux/property.h>23#include <linux/regulator/consumer.h>24#include <linux/gpio/consumer.h>25#include <linux/interrupt.h>26#include <linux/math64.h>27#include <linux/pm.h>28 29#define CM3605_PROX_CHANNEL 030#define CM3605_ALS_CHANNEL 131#define CM3605_AOUT_TYP_MAX_MV 155032/* It should not go above 1.650V according to the data sheet */33#define CM3605_AOUT_MAX_MV 165034 35/**36 * struct cm3605 - CM3605 state37 * @dev: pointer to parent device38 * @vdd: regulator controlling VDD39 * @aset: sleep enable GPIO, high = sleep40 * @aout: IIO ADC channel to convert the AOUT signal41 * @als_max: maximum LUX detection (depends on RSET)42 * @dir: proximity direction: start as FALLING43 * @led: trigger for the infrared LED used by the proximity sensor44 */45struct cm3605 {46 struct device *dev;47 struct regulator *vdd;48 struct gpio_desc *aset;49 struct iio_channel *aout;50 s32 als_max;51 enum iio_event_direction dir;52 struct led_trigger *led;53};54 55static irqreturn_t cm3605_prox_irq(int irq, void *d)56{57 struct iio_dev *indio_dev = d;58 struct cm3605 *cm3605 = iio_priv(indio_dev);59 u64 ev;60 61 ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, CM3605_PROX_CHANNEL,62 IIO_EV_TYPE_THRESH, cm3605->dir);63 iio_push_event(indio_dev, ev, iio_get_time_ns(indio_dev));64 65 /* Invert the edge for each event */66 if (cm3605->dir == IIO_EV_DIR_RISING)67 cm3605->dir = IIO_EV_DIR_FALLING;68 else69 cm3605->dir = IIO_EV_DIR_RISING;70 71 return IRQ_HANDLED;72}73 74static int cm3605_get_lux(struct cm3605 *cm3605)75{76 int ret, res;77 s64 lux;78 79 ret = iio_read_channel_processed(cm3605->aout, &res);80 if (ret < 0)81 return ret;82 83 dev_dbg(cm3605->dev, "read %d mV from ADC\n", res);84 85 /*86 * AOUT has an offset of ~30mV then linear at dark87 * then goes from 2.54 up to 650 LUX yielding 1.55V88 * (1550 mV) so scale the returned value to this interval89 * using simple linear interpolation.90 */91 if (res < 30)92 return 0;93 if (res > CM3605_AOUT_MAX_MV)94 dev_err(cm3605->dev, "device out of range\n");95 96 /* Remove bias */97 lux = res - 30;98 99 /* Linear interpolation between 0 and ALS typ max */100 lux *= cm3605->als_max;101 lux = div64_s64(lux, CM3605_AOUT_TYP_MAX_MV);102 103 return lux;104}105 106static int cm3605_read_raw(struct iio_dev *indio_dev,107 struct iio_chan_spec const *chan,108 int *val, int *val2, long mask)109{110 struct cm3605 *cm3605 = iio_priv(indio_dev);111 int ret;112 113 switch (mask) {114 case IIO_CHAN_INFO_RAW:115 switch (chan->type) {116 case IIO_LIGHT:117 ret = cm3605_get_lux(cm3605);118 if (ret < 0)119 return ret;120 *val = ret;121 return IIO_VAL_INT;122 default:123 return -EINVAL;124 }125 default:126 return -EINVAL;127 }128}129 130static const struct iio_info cm3605_info = {131 .read_raw = cm3605_read_raw,132};133 134static const struct iio_event_spec cm3605_events[] = {135 {136 .type = IIO_EV_TYPE_THRESH,137 .dir = IIO_EV_DIR_EITHER,138 .mask_separate = BIT(IIO_EV_INFO_ENABLE),139 },140};141 142static const struct iio_chan_spec cm3605_channels[] = {143 {144 .type = IIO_PROXIMITY,145 .event_spec = cm3605_events,146 .num_event_specs = ARRAY_SIZE(cm3605_events),147 },148 {149 .type = IIO_LIGHT,150 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),151 .channel = CM3605_ALS_CHANNEL,152 },153};154 155static int cm3605_probe(struct platform_device *pdev)156{157 struct cm3605 *cm3605;158 struct iio_dev *indio_dev;159 struct device *dev = &pdev->dev;160 enum iio_chan_type ch_type;161 u32 rset;162 int irq;163 int ret;164 165 indio_dev = devm_iio_device_alloc(dev, sizeof(*cm3605));166 if (!indio_dev)167 return -ENOMEM;168 platform_set_drvdata(pdev, indio_dev);169 170 cm3605 = iio_priv(indio_dev);171 cm3605->dev = dev;172 cm3605->dir = IIO_EV_DIR_FALLING;173 174 ret = device_property_read_u32(dev, "capella,aset-resistance-ohms", &rset);175 if (ret) {176 dev_info(dev, "no RSET specified, assuming 100K\n");177 rset = 100000;178 }179 switch (rset) {180 case 50000:181 cm3605->als_max = 650;182 break;183 case 100000:184 cm3605->als_max = 300;185 break;186 case 300000:187 cm3605->als_max = 100;188 break;189 case 600000:190 cm3605->als_max = 50;191 break;192 default:193 dev_info(dev, "non-standard resistance\n");194 return -EINVAL;195 }196 197 cm3605->aout = devm_iio_channel_get(dev, "aout");198 if (IS_ERR(cm3605->aout)) {199 ret = PTR_ERR(cm3605->aout);200 ret = (ret == -ENODEV) ? -EPROBE_DEFER : ret;201 return dev_err_probe(dev, ret, "failed to get AOUT ADC channel\n");202 }203 ret = iio_get_channel_type(cm3605->aout, &ch_type);204 if (ret < 0)205 return ret;206 if (ch_type != IIO_VOLTAGE) {207 dev_err(dev, "wrong type of IIO channel specified for AOUT\n");208 return -EINVAL;209 }210 211 cm3605->vdd = devm_regulator_get(dev, "vdd");212 if (IS_ERR(cm3605->vdd))213 return dev_err_probe(dev, PTR_ERR(cm3605->vdd),214 "failed to get VDD regulator\n");215 216 ret = regulator_enable(cm3605->vdd);217 if (ret) {218 dev_err(dev, "failed to enable VDD regulator\n");219 return ret;220 }221 222 cm3605->aset = devm_gpiod_get(dev, "aset", GPIOD_OUT_HIGH);223 if (IS_ERR(cm3605->aset)) {224 ret = dev_err_probe(dev, PTR_ERR(cm3605->aset), "no ASET GPIO\n");225 goto out_disable_vdd;226 }227 228 irq = platform_get_irq(pdev, 0);229 if (irq < 0) {230 ret = irq;231 goto out_disable_aset;232 }233 234 ret = devm_request_threaded_irq(dev, irq, cm3605_prox_irq,235 NULL, 0, "cm3605", indio_dev);236 if (ret) {237 dev_err(dev, "unable to request IRQ\n");238 goto out_disable_aset;239 }240 241 /* Just name the trigger the same as the driver */242 led_trigger_register_simple("cm3605", &cm3605->led);243 led_trigger_event(cm3605->led, LED_FULL);244 245 indio_dev->info = &cm3605_info;246 indio_dev->name = "cm3605";247 indio_dev->channels = cm3605_channels;248 indio_dev->num_channels = ARRAY_SIZE(cm3605_channels);249 indio_dev->modes = INDIO_DIRECT_MODE;250 251 ret = iio_device_register(indio_dev);252 if (ret)253 goto out_remove_trigger;254 dev_info(dev, "Capella Microsystems CM3605 enabled range 0..%d LUX\n",255 cm3605->als_max);256 257 return 0;258 259out_remove_trigger:260 led_trigger_event(cm3605->led, LED_OFF);261 led_trigger_unregister_simple(cm3605->led);262out_disable_aset:263 gpiod_set_value_cansleep(cm3605->aset, 0);264out_disable_vdd:265 regulator_disable(cm3605->vdd);266 return ret;267}268 269static void cm3605_remove(struct platform_device *pdev)270{271 struct iio_dev *indio_dev = platform_get_drvdata(pdev);272 struct cm3605 *cm3605 = iio_priv(indio_dev);273 274 led_trigger_event(cm3605->led, LED_OFF);275 led_trigger_unregister_simple(cm3605->led);276 gpiod_set_value_cansleep(cm3605->aset, 0);277 iio_device_unregister(indio_dev);278 regulator_disable(cm3605->vdd);279}280 281static int cm3605_pm_suspend(struct device *dev)282{283 struct iio_dev *indio_dev = dev_get_drvdata(dev);284 struct cm3605 *cm3605 = iio_priv(indio_dev);285 286 led_trigger_event(cm3605->led, LED_OFF);287 regulator_disable(cm3605->vdd);288 289 return 0;290}291 292static int cm3605_pm_resume(struct device *dev)293{294 struct iio_dev *indio_dev = dev_get_drvdata(dev);295 struct cm3605 *cm3605 = iio_priv(indio_dev);296 int ret;297 298 ret = regulator_enable(cm3605->vdd);299 if (ret)300 dev_err(dev, "failed to enable regulator in resume path\n");301 led_trigger_event(cm3605->led, LED_FULL);302 303 return 0;304}305static DEFINE_SIMPLE_DEV_PM_OPS(cm3605_dev_pm_ops, cm3605_pm_suspend,306 cm3605_pm_resume);307 308static const struct of_device_id cm3605_of_match[] = {309 {.compatible = "capella,cm3605"},310 { },311};312MODULE_DEVICE_TABLE(of, cm3605_of_match);313 314static struct platform_driver cm3605_driver = {315 .driver = {316 .name = "cm3605",317 .of_match_table = cm3605_of_match,318 .pm = pm_sleep_ptr(&cm3605_dev_pm_ops),319 },320 .probe = cm3605_probe,321 .remove_new = cm3605_remove,322};323module_platform_driver(cm3605_driver);324 325MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");326MODULE_DESCRIPTION("CM3605 ambient light and proximity sensor driver");327MODULE_LICENSE("GPL");328