| // 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/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 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 = 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)) { |
| 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) |
| return dev_err_probe(dev, irq, "failed to get irq\n"); |
| |
| 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 __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 <linus.walleij@linaro.org>"); |
| MODULE_DESCRIPTION("CM3605 ambient light and proximity sensor driver"); |
| MODULE_LICENSE("GPL"); |