--- /dev/null
+// 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>
+ *
+ * Datasheet available at
+ * <https://www.st.com/resource/en/datasheet/vl53l0x.pdf>
+ *
+ * Default 7-bit i2c slave address 0x29.
+ *
+ * TODO: FIFO buffer, continuous mode, interrupts, range selection,
+ * sensor ID check.
+ */
+
+#include <linux/delay.h>
+#include <linux/i2c.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_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;
+};
+
+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;
+
+ ret = i2c_smbus_write_byte_data(client, VL_REG_SYSRANGE_START, 1);
+ if (ret < 0)
+ return ret;
+
+ 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->dev.parent = &client->dev;
+ 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;
+
+ 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");
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