1 files changed, 304 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..c7c4d33d3
--- /dev/null
+++ b/drivers/iio/proximity/vl53l0x-i2c.c
@@ -0,0 +1,304 @@
+// 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/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/irq.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;
+	struct regulator *vdd_supply;
+	struct gpio_desc *reset_gpio;
+};
+
+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)
+{
+	int irq_flags = irq_get_trigger_type(client->irq);
+	struct vl53l0x_data *data = iio_priv(indio_dev);
+	int ret;
+
+	if (!irq_flags)
+		irq_flags = IRQF_TRIGGER_FALLING;
+
+	ret = devm_request_irq(&client->dev, client->irq, vl53l0x_handle_irq,
+			irq_flags, 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 void vl53l0x_power_off(void *_data)
+{
+	struct vl53l0x_data *data = _data;
+
+	gpiod_set_value_cansleep(data->reset_gpio, 1);
+
+	regulator_disable(data->vdd_supply);
+}
+
+static int vl53l0x_power_on(struct vl53l0x_data *data)
+{
+	int ret;
+
+	ret = regulator_enable(data->vdd_supply);
+	if (ret)
+		return ret;
+
+	gpiod_set_value_cansleep(data->reset_gpio, 0);
+
+	usleep_range(3200, 5000);
+
+	return 0;
+}
+
+static int vl53l0x_probe(struct i2c_client *client)
+{
+	struct vl53l0x_data *data;
+	struct iio_dev *indio_dev;
+	int error;
+
+	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;
+
+	data->vdd_supply = devm_regulator_get(&client->dev, "vdd");
+	if (IS_ERR(data->vdd_supply))
+		return dev_err_probe(&client->dev, PTR_ERR(data->vdd_supply),
+				     "Unable to get VDD regulator\n");
+
+	data->reset_gpio = devm_gpiod_get_optional(&client->dev, "reset", GPIOD_OUT_HIGH);
+	if (IS_ERR(data->reset_gpio))
+		return dev_err_probe(&client->dev, PTR_ERR(data->reset_gpio),
+				     "Cannot get reset GPIO\n");
+
+	error = vl53l0x_power_on(data);
+	if (error)
+		return dev_err_probe(&client->dev, error,
+				     "Failed to power on the chip\n");
+
+	error = devm_add_action_or_reset(&client->dev, vl53l0x_power_off, data);
+	if (error)
+		return dev_err_probe(&client->dev, error,
+				     "Failed to install poweroff action\n");
+
+	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 i2c_device_id vl53l0x_id[] = {
+	{ "vl53l0x", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, vl53l0x_id);
+
+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,
+	.id_table = vl53l0x_id,
+};
+module_i2c_driver(vl53l0x_driver);
+
+MODULE_AUTHOR("Song Qiang <songqiang1304521@gmail.com>");
+MODULE_DESCRIPTION("ST vl53l0x ToF ranging sensor driver");
+MODULE_LICENSE("GPL v2");