diff options
Diffstat (limited to 'drivers/iio/light/apds9300.c')
| -rw-r--r-- | drivers/iio/light/apds9300.c | 512 |
1 files changed, 512 insertions, 0 deletions
diff --git a/drivers/iio/light/apds9300.c b/drivers/iio/light/apds9300.c new file mode 100644 index 000000000000..66a58bda6dc8 --- /dev/null +++ b/drivers/iio/light/apds9300.c @@ -0,0 +1,512 @@ +/* + * apds9300.c - IIO driver for Avago APDS9300 ambient light sensor + * + * Copyright 2013 Oleksandr Kravchenko <o.v.kravchenko@globallogic.com> + * + * This file is subject to the terms and conditions of version 2 of + * the GNU General Public License. See the file COPYING in the main + * directory of this archive for more details. + */ + +#include <linux/module.h> +#include <linux/slab.h> +#include <linux/pm.h> +#include <linux/i2c.h> +#include <linux/err.h> +#include <linux/mutex.h> +#include <linux/interrupt.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/events.h> + +#define APDS9300_DRV_NAME "apds9300" +#define APDS9300_IRQ_NAME "apds9300_event" + +/* Command register bits */ +#define APDS9300_CMD BIT(7) /* Select command register. Must write as 1 */ +#define APDS9300_WORD BIT(5) /* I2C write/read: if 1 word, if 0 byte */ +#define APDS9300_CLEAR BIT(6) /* Interrupt clear. Clears pending interrupt */ + +/* Register set */ +#define APDS9300_CONTROL 0x00 /* Control of basic functions */ +#define APDS9300_THRESHLOWLOW 0x02 /* Low byte of low interrupt threshold */ +#define APDS9300_THRESHHIGHLOW 0x04 /* Low byte of high interrupt threshold */ +#define APDS9300_INTERRUPT 0x06 /* Interrupt control */ +#define APDS9300_DATA0LOW 0x0c /* Low byte of ADC channel 0 */ +#define APDS9300_DATA1LOW 0x0e /* Low byte of ADC channel 1 */ + +/* Power on/off value for APDS9300_CONTROL register */ +#define APDS9300_POWER_ON 0x03 +#define APDS9300_POWER_OFF 0x00 + +/* Interrupts */ +#define APDS9300_INTR_ENABLE 0x10 +/* Interrupt Persist Function: Any value outside of threshold range */ +#define APDS9300_THRESH_INTR 0x01 + +#define APDS9300_THRESH_MAX 0xffff /* Max threshold value */ + +struct apds9300_data { + struct i2c_client *client; + struct mutex mutex; + int power_state; + int thresh_low; + int thresh_hi; + int intr_en; +}; + +/* Lux calculation */ + +/* Calculated values 1000 * (CH1/CH0)^1.4 for CH1/CH0 from 0 to 0.52 */ +static const u16 apds9300_lux_ratio[] = { + 0, 2, 4, 7, 11, 15, 19, 24, 29, 34, 40, 45, 51, 57, 64, 70, 77, 84, 91, + 98, 105, 112, 120, 128, 136, 144, 152, 160, 168, 177, 185, 194, 203, + 212, 221, 230, 239, 249, 258, 268, 277, 287, 297, 307, 317, 327, 337, + 347, 358, 368, 379, 390, 400, +}; + +static unsigned long apds9300_calculate_lux(u16 ch0, u16 ch1) +{ + unsigned long lux, tmp; + + /* avoid division by zero */ + if (ch0 == 0) + return 0; + + tmp = DIV_ROUND_UP(ch1 * 100, ch0); + if (tmp <= 52) { + lux = 3150 * ch0 - (unsigned long)DIV_ROUND_UP_ULL(ch0 + * apds9300_lux_ratio[tmp] * 5930ull, 1000); + } else if (tmp <= 65) { + lux = 2290 * ch0 - 2910 * ch1; + } else if (tmp <= 80) { + lux = 1570 * ch0 - 1800 * ch1; + } else if (tmp <= 130) { + lux = 338 * ch0 - 260 * ch1; + } else { + lux = 0; + } + + return lux / 100000; +} + +static int apds9300_get_adc_val(struct apds9300_data *data, int adc_number) +{ + int ret; + u8 flags = APDS9300_CMD | APDS9300_WORD; + + if (!data->power_state) + return -EBUSY; + + /* Select ADC0 or ADC1 data register */ + flags |= adc_number ? APDS9300_DATA1LOW : APDS9300_DATA0LOW; + + ret = i2c_smbus_read_word_data(data->client, flags); + if (ret < 0) + dev_err(&data->client->dev, + "failed to read ADC%d value\n", adc_number); + + return ret; +} + +static int apds9300_set_thresh_low(struct apds9300_data *data, int value) +{ + int ret; + + if (!data->power_state) + return -EBUSY; + + if (value > APDS9300_THRESH_MAX) + return -EINVAL; + + ret = i2c_smbus_write_word_data(data->client, APDS9300_THRESHLOWLOW + | APDS9300_CMD | APDS9300_WORD, value); + if (ret) { + dev_err(&data->client->dev, "failed to set thresh_low\n"); + return ret; + } + data->thresh_low = value; + + return 0; +} + +static int apds9300_set_thresh_hi(struct apds9300_data *data, int value) +{ + int ret; + + if (!data->power_state) + return -EBUSY; + + if (value > APDS9300_THRESH_MAX) + return -EINVAL; + + ret = i2c_smbus_write_word_data(data->client, APDS9300_THRESHHIGHLOW + | APDS9300_CMD | APDS9300_WORD, value); + if (ret) { + dev_err(&data->client->dev, "failed to set thresh_hi\n"); + return ret; + } + data->thresh_hi = value; + + return 0; +} + +static int apds9300_set_intr_state(struct apds9300_data *data, int state) +{ + int ret; + u8 cmd; + + if (!data->power_state) + return -EBUSY; + + cmd = state ? APDS9300_INTR_ENABLE | APDS9300_THRESH_INTR : 0x00; + ret = i2c_smbus_write_byte_data(data->client, + APDS9300_INTERRUPT | APDS9300_CMD, cmd); + if (ret) { + dev_err(&data->client->dev, + "failed to set interrupt state %d\n", state); + return ret; + } + data->intr_en = state; + + return 0; +} + +static int apds9300_set_power_state(struct apds9300_data *data, int state) +{ + int ret; + u8 cmd; + + cmd = state ? APDS9300_POWER_ON : APDS9300_POWER_OFF; + ret = i2c_smbus_write_byte_data(data->client, + APDS9300_CONTROL | APDS9300_CMD, cmd); + if (ret) { + dev_err(&data->client->dev, + "failed to set power state %d\n", state); + return ret; + } + data->power_state = state; + + return 0; +} + +static void apds9300_clear_intr(struct apds9300_data *data) +{ + int ret; + + ret = i2c_smbus_write_byte(data->client, APDS9300_CLEAR | APDS9300_CMD); + if (ret < 0) + dev_err(&data->client->dev, "failed to clear interrupt\n"); +} + +static int apds9300_chip_init(struct apds9300_data *data) +{ + int ret; + + /* Need to set power off to ensure that the chip is off */ + ret = apds9300_set_power_state(data, 0); + if (ret < 0) + goto err; + /* + * Probe the chip. To do so we try to power up the device and then to + * read back the 0x03 code + */ + ret = apds9300_set_power_state(data, 1); + if (ret < 0) + goto err; + ret = i2c_smbus_read_byte_data(data->client, + APDS9300_CONTROL | APDS9300_CMD); + if (ret != APDS9300_POWER_ON) { + ret = -ENODEV; + goto err; + } + /* + * Disable interrupt to ensure thai it is doesn't enable + * i.e. after device soft reset + */ + ret = apds9300_set_intr_state(data, 0); + if (ret < 0) + goto err; + + return 0; + +err: + dev_err(&data->client->dev, "failed to init the chip\n"); + return ret; +} + +static int apds9300_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, int *val2, + long mask) +{ + int ch0, ch1, ret = -EINVAL; + struct apds9300_data *data = iio_priv(indio_dev); + + mutex_lock(&data->mutex); + switch (chan->type) { + case IIO_LIGHT: + ch0 = apds9300_get_adc_val(data, 0); + if (ch0 < 0) { + ret = ch0; + break; + } + ch1 = apds9300_get_adc_val(data, 1); + if (ch1 < 0) { + ret = ch1; + break; + } + *val = apds9300_calculate_lux(ch0, ch1); + ret = IIO_VAL_INT; + break; + case IIO_INTENSITY: + ret = apds9300_get_adc_val(data, chan->channel); + if (ret < 0) + break; + *val = ret; + ret = IIO_VAL_INT; + break; + default: + break; + } + mutex_unlock(&data->mutex); + + return ret; +} + +static int apds9300_read_thresh(struct iio_dev *indio_dev, u64 event_code, + int *val) +{ + struct apds9300_data *data = iio_priv(indio_dev); + + switch (IIO_EVENT_CODE_EXTRACT_DIR(event_code)) { + case IIO_EV_DIR_RISING: + *val = data->thresh_hi; + break; + case IIO_EV_DIR_FALLING: + *val = data->thresh_low; + break; + default: + return -EINVAL; + } + + return 0; +} + +static int apds9300_write_thresh(struct iio_dev *indio_dev, u64 event_code, + int val) +{ + struct apds9300_data *data = iio_priv(indio_dev); + int ret; + + mutex_lock(&data->mutex); + if (IIO_EVENT_CODE_EXTRACT_DIR(event_code) == IIO_EV_DIR_RISING) + ret = apds9300_set_thresh_hi(data, val); + else + ret = apds9300_set_thresh_low(data, val); + mutex_unlock(&data->mutex); + + return ret; +} + +static int apds9300_read_interrupt_config(struct iio_dev *indio_dev, + u64 event_code) +{ + struct apds9300_data *data = iio_priv(indio_dev); + + return data->intr_en; +} + +static int apds9300_write_interrupt_config(struct iio_dev *indio_dev, + u64 event_code, int state) +{ + struct apds9300_data *data = iio_priv(indio_dev); + int ret; + + mutex_lock(&data->mutex); + ret = apds9300_set_intr_state(data, state); + mutex_unlock(&data->mutex); + + return ret; +} + +static const struct iio_info apds9300_info_no_irq = { + .driver_module = THIS_MODULE, + .read_raw = apds9300_read_raw, +}; + +static const struct iio_info apds9300_info = { + .driver_module = THIS_MODULE, + .read_raw = apds9300_read_raw, + .read_event_value = apds9300_read_thresh, + .write_event_value = apds9300_write_thresh, + .read_event_config = apds9300_read_interrupt_config, + .write_event_config = apds9300_write_interrupt_config, +}; + +static const struct iio_chan_spec apds9300_channels[] = { + { + .type = IIO_LIGHT, + .channel = 0, + .indexed = true, + .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED), + }, { + .type = IIO_INTENSITY, + .channel = 0, + .channel2 = IIO_MOD_LIGHT_BOTH, + .indexed = true, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .event_mask = (IIO_EV_BIT(IIO_EV_TYPE_THRESH, + IIO_EV_DIR_RISING) | + IIO_EV_BIT(IIO_EV_TYPE_THRESH, + IIO_EV_DIR_FALLING)), + }, { + .type = IIO_INTENSITY, + .channel = 1, + .channel2 = IIO_MOD_LIGHT_IR, + .indexed = true, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + }, +}; + +static irqreturn_t apds9300_interrupt_handler(int irq, void *private) +{ + struct iio_dev *dev_info = private; + struct apds9300_data *data = iio_priv(dev_info); + + iio_push_event(dev_info, + IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0, + IIO_EV_TYPE_THRESH, + IIO_EV_DIR_EITHER), + iio_get_time_ns()); + + apds9300_clear_intr(data); + + return IRQ_HANDLED; +} + +static int apds9300_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct apds9300_data *data; + struct iio_dev *indio_dev; + int ret; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + data->client = client; + + ret = apds9300_chip_init(data); + if (ret < 0) + goto err; + + mutex_init(&data->mutex); + + indio_dev->dev.parent = &client->dev; + indio_dev->channels = apds9300_channels; + indio_dev->num_channels = ARRAY_SIZE(apds9300_channels); + indio_dev->name = APDS9300_DRV_NAME; + indio_dev->modes = INDIO_DIRECT_MODE; + + if (client->irq) + indio_dev->info = &apds9300_info; + else + indio_dev->info = &apds9300_info_no_irq; + + if (client->irq) { + ret = devm_request_threaded_irq(&client->dev, client->irq, + NULL, apds9300_interrupt_handler, + IRQF_TRIGGER_FALLING | IRQF_ONESHOT, + APDS9300_IRQ_NAME, indio_dev); + if (ret) { + dev_err(&client->dev, "irq request error %d\n", -ret); + goto err; + } + } + + ret = iio_device_register(indio_dev); + if (ret < 0) + goto err; + + return 0; + +err: + /* Ensure that power off in case of error */ + apds9300_set_power_state(data, 0); + return ret; +} + +static int apds9300_remove(struct i2c_client *client) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(client); + struct apds9300_data *data = iio_priv(indio_dev); + + iio_device_unregister(indio_dev); + + /* Ensure that power off and interrupts are disabled */ + apds9300_set_intr_state(data, 0); + apds9300_set_power_state(data, 0); + + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int apds9300_suspend(struct device *dev) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + struct apds9300_data *data = iio_priv(indio_dev); + int ret; + + mutex_lock(&data->mutex); + ret = apds9300_set_power_state(data, 0); + mutex_unlock(&data->mutex); + + return ret; +} + +static int apds9300_resume(struct device *dev) +{ + struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); + struct apds9300_data *data = iio_priv(indio_dev); + int ret; + + mutex_lock(&data->mutex); + ret = apds9300_set_power_state(data, 1); + mutex_unlock(&data->mutex); + + return ret; +} + +static SIMPLE_DEV_PM_OPS(apds9300_pm_ops, apds9300_suspend, apds9300_resume); +#define APDS9300_PM_OPS (&apds9300_pm_ops) +#else +#define APDS9300_PM_OPS NULL +#endif + +static struct i2c_device_id apds9300_id[] = { + { APDS9300_DRV_NAME, 0 }, + { } +}; + +MODULE_DEVICE_TABLE(i2c, apds9300_id); + +static struct i2c_driver apds9300_driver = { + .driver = { + .name = APDS9300_DRV_NAME, + .owner = THIS_MODULE, + .pm = APDS9300_PM_OPS, + }, + .probe = apds9300_probe, + .remove = apds9300_remove, + .id_table = apds9300_id, +}; + +module_i2c_driver(apds9300_driver); + +MODULE_AUTHOR("Kravchenko Oleksandr <o.v.kravchenko@globallogic.com>"); +MODULE_AUTHOR("GlobalLogic inc."); +MODULE_DESCRIPTION("APDS9300 ambient light photo sensor driver"); +MODULE_LICENSE("GPL"); |