|  | // SPDX-License-Identifier: GPL-2.0-only | 
|  | /* | 
|  | * CM3605 Ambient Light and Proximity Sensor | 
|  | * | 
|  | * Copyright (C) 2016 Linaro Ltd. | 
|  | * Author: Linus Walleij <[email protected]> | 
|  | * | 
|  | * 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/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/of.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; | 
|  | struct device_node *np = dev->of_node; | 
|  | enum iio_chan_type ch_type; | 
|  | u32 rset; | 
|  | 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 = of_property_read_u32(np, "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)) { | 
|  | if (PTR_ERR(cm3605->aout) == -ENODEV) { | 
|  | dev_err(dev, "no ADC, deferring...\n"); | 
|  | return -EPROBE_DEFER; | 
|  | } | 
|  | dev_err(dev, "failed to get AOUT ADC channel\n"); | 
|  | return PTR_ERR(cm3605->aout); | 
|  | } | 
|  | 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)) { | 
|  | dev_err(dev, "failed to get VDD regulator\n"); | 
|  | return PTR_ERR(cm3605->vdd); | 
|  | } | 
|  | 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)) { | 
|  | dev_err(dev, "no ASET GPIO\n"); | 
|  | ret = PTR_ERR(cm3605->aset); | 
|  | goto out_disable_vdd; | 
|  | } | 
|  |  | 
|  | ret = devm_request_threaded_irq(dev, platform_get_irq(pdev, 0), | 
|  | 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 __maybe_unused 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 __maybe_unused 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 const struct dev_pm_ops cm3605_dev_pm_ops = { | 
|  | SET_SYSTEM_SLEEP_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 = &cm3605_dev_pm_ops, | 
|  | }, | 
|  | .probe = cm3605_probe, | 
|  | .remove = cm3605_remove, | 
|  | }; | 
|  | module_platform_driver(cm3605_driver); | 
|  |  | 
|  | MODULE_AUTHOR("Linus Walleij <[email protected]>"); | 
|  | MODULE_DESCRIPTION("CM3605 ambient light and proximity sensor driver"); | 
|  | MODULE_LICENSE("GPL"); |