diff options
Diffstat (limited to 'drivers/iio/proximity/vl53l0x-i2c.c')
| -rw-r--r-- | drivers/iio/proximity/vl53l0x-i2c.c | 244 |
1 files changed, 244 insertions, 0 deletions
diff --git a/drivers/iio/proximity/vl53l0x-i2c.c b/drivers/iio/proximity/vl53l0x-i2c.c new file mode 100644 index 000000000..3d3ab8642 --- /dev/null +++ b/drivers/iio/proximity/vl53l0x-i2c.c @@ -0,0 +1,244 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Support for ST VL53L0X FlightSense ToF Ranging Sensor on a i2c bus. + * + * Copyright (C) 2016 STMicroelectronics Imaging Division. + * Copyright (C) 2018 Song Qiang <songqiang1304521@gmail.com> + * Copyright (C) 2020 Ivan Drobyshevskyi <drobyshevskyi@gmail.com> + * + * Datasheet available at + * <https://www.st.com/resource/en/datasheet/vl53l0x.pdf> + * + * Default 7-bit i2c slave address 0x29. + * + * TODO: FIFO buffer, continuous mode, range selection, sensor ID check. + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/module.h> + +#include <linux/iio/iio.h> + +#define VL_REG_SYSRANGE_START 0x00 + +#define VL_REG_SYSRANGE_MODE_MASK GENMASK(3, 0) +#define VL_REG_SYSRANGE_MODE_SINGLESHOT 0x00 +#define VL_REG_SYSRANGE_MODE_START_STOP BIT(0) +#define VL_REG_SYSRANGE_MODE_BACKTOBACK BIT(1) +#define VL_REG_SYSRANGE_MODE_TIMED BIT(2) +#define VL_REG_SYSRANGE_MODE_HISTOGRAM BIT(3) + +#define VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO 0x0A +#define VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY BIT(2) + +#define VL_REG_SYSTEM_INTERRUPT_CLEAR 0x0B + +#define VL_REG_RESULT_INT_STATUS 0x13 +#define VL_REG_RESULT_RANGE_STATUS 0x14 +#define VL_REG_RESULT_RANGE_STATUS_COMPLETE BIT(0) + +struct vl53l0x_data { + struct i2c_client *client; + struct completion completion; +}; + +static irqreturn_t vl53l0x_handle_irq(int irq, void *priv) +{ + struct iio_dev *indio_dev = priv; + struct vl53l0x_data *data = iio_priv(indio_dev); + + complete(&data->completion); + + return IRQ_HANDLED; +} + +static int vl53l0x_configure_irq(struct i2c_client *client, + struct iio_dev *indio_dev) +{ + struct vl53l0x_data *data = iio_priv(indio_dev); + int ret; + + ret = devm_request_irq(&client->dev, client->irq, vl53l0x_handle_irq, + IRQF_TRIGGER_FALLING, indio_dev->name, indio_dev); + if (ret) { + dev_err(&client->dev, "devm_request_irq error: %d\n", ret); + return ret; + } + + ret = i2c_smbus_write_byte_data(data->client, + VL_REG_SYSTEM_INTERRUPT_CONFIG_GPIO, + VL_REG_SYSTEM_INTERRUPT_GPIO_NEW_SAMPLE_READY); + if (ret < 0) + dev_err(&client->dev, "failed to configure IRQ: %d\n", ret); + + return ret; +} + +static void vl53l0x_clear_irq(struct vl53l0x_data *data) +{ + struct device *dev = &data->client->dev; + int ret; + + ret = i2c_smbus_write_byte_data(data->client, + VL_REG_SYSTEM_INTERRUPT_CLEAR, 1); + if (ret < 0) + dev_err(dev, "failed to clear error irq: %d\n", ret); + + ret = i2c_smbus_write_byte_data(data->client, + VL_REG_SYSTEM_INTERRUPT_CLEAR, 0); + if (ret < 0) + dev_err(dev, "failed to clear range irq: %d\n", ret); + + ret = i2c_smbus_read_byte_data(data->client, VL_REG_RESULT_INT_STATUS); + if (ret < 0 || ret & 0x07) + dev_err(dev, "failed to clear irq: %d\n", ret); +} + +static int vl53l0x_read_proximity(struct vl53l0x_data *data, + const struct iio_chan_spec *chan, + int *val) +{ + struct i2c_client *client = data->client; + u16 tries = 20; + u8 buffer[12]; + int ret; + unsigned long time_left; + + ret = i2c_smbus_write_byte_data(client, VL_REG_SYSRANGE_START, 1); + if (ret < 0) + return ret; + + if (data->client->irq) { + reinit_completion(&data->completion); + + time_left = wait_for_completion_timeout(&data->completion, HZ/10); + if (time_left == 0) + return -ETIMEDOUT; + + vl53l0x_clear_irq(data); + } else { + do { + ret = i2c_smbus_read_byte_data(client, + VL_REG_RESULT_RANGE_STATUS); + if (ret < 0) + return ret; + + if (ret & VL_REG_RESULT_RANGE_STATUS_COMPLETE) + break; + + usleep_range(1000, 5000); + } while (--tries); + if (!tries) + return -ETIMEDOUT; + } + + ret = i2c_smbus_read_i2c_block_data(client, VL_REG_RESULT_RANGE_STATUS, + 12, buffer); + if (ret < 0) + return ret; + else if (ret != 12) + return -EREMOTEIO; + + /* Values should be between 30~1200 in millimeters. */ + *val = (buffer[10] << 8) + buffer[11]; + + return 0; +} + +static const struct iio_chan_spec vl53l0x_channels[] = { + { + .type = IIO_DISTANCE, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_SCALE), + }, +}; + +static int vl53l0x_read_raw(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + int *val, int *val2, long mask) +{ + struct vl53l0x_data *data = iio_priv(indio_dev); + int ret; + + if (chan->type != IIO_DISTANCE) + return -EINVAL; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + ret = vl53l0x_read_proximity(data, chan, val); + if (ret < 0) + return ret; + + return IIO_VAL_INT; + case IIO_CHAN_INFO_SCALE: + *val = 0; + *val2 = 1000; + + return IIO_VAL_INT_PLUS_MICRO; + default: + return -EINVAL; + } +} + +static const struct iio_info vl53l0x_info = { + .read_raw = vl53l0x_read_raw, +}; + +static int vl53l0x_probe(struct i2c_client *client) +{ + struct vl53l0x_data *data; + struct iio_dev *indio_dev; + + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + data->client = client; + i2c_set_clientdata(client, indio_dev); + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_I2C_BLOCK | + I2C_FUNC_SMBUS_BYTE_DATA)) + return -EOPNOTSUPP; + + indio_dev->name = "vl53l0x"; + indio_dev->info = &vl53l0x_info; + indio_dev->channels = vl53l0x_channels; + indio_dev->num_channels = ARRAY_SIZE(vl53l0x_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + + /* usage of interrupt is optional */ + if (client->irq) { + int ret; + + init_completion(&data->completion); + + ret = vl53l0x_configure_irq(client, indio_dev); + if (ret) + return ret; + } + + return devm_iio_device_register(&client->dev, indio_dev); +} + +static const struct of_device_id st_vl53l0x_dt_match[] = { + { .compatible = "st,vl53l0x", }, + { } +}; +MODULE_DEVICE_TABLE(of, st_vl53l0x_dt_match); + +static struct i2c_driver vl53l0x_driver = { + .driver = { + .name = "vl53l0x-i2c", + .of_match_table = st_vl53l0x_dt_match, + }, + .probe_new = vl53l0x_probe, +}; +module_i2c_driver(vl53l0x_driver); + +MODULE_AUTHOR("Song Qiang <songqiang1304521@gmail.com>"); +MODULE_DESCRIPTION("ST vl53l0x ToF ranging sensor driver"); +MODULE_LICENSE("GPL v2"); |