1 files changed, 377 insertions, 0 deletions

diff --git a/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
new file mode 100644
index 000000000..791a33d52
--- /dev/null
+++ b/drivers/iio/proximity/pulsedlight-lidar-lite-v2.c
@@ -0,0 +1,377 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * pulsedlight-lidar-lite-v2.c - Support for PulsedLight LIDAR sensor
+ *
+ * Copyright (C) 2015, 2017-2018
+ * Author: Matt Ranostay <matt.ranostay@konsulko.com>
+ *
+ * TODO: interrupt mode, and signal strength reporting
+ */
+
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/pm_runtime.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
+
+#define LIDAR_REG_CONTROL		0x00
+#define LIDAR_REG_CONTROL_ACQUIRE	BIT(2)
+
+#define LIDAR_REG_STATUS		0x01
+#define LIDAR_REG_STATUS_INVALID	BIT(3)
+#define LIDAR_REG_STATUS_READY		BIT(0)
+
+#define LIDAR_REG_DATA_HBYTE		0x0f
+#define LIDAR_REG_DATA_LBYTE		0x10
+#define LIDAR_REG_DATA_WORD_READ	BIT(7)
+
+#define LIDAR_REG_PWR_CONTROL	0x65
+
+#define LIDAR_DRV_NAME "lidar"
+
+struct lidar_data {
+	struct iio_dev *indio_dev;
+	struct i2c_client *client;
+
+	int (*xfer)(struct lidar_data *data, u8 reg, u8 *val, int len);
+	int i2c_enabled;
+
+	/* Ensure timestamp is naturally aligned */
+	struct {
+		u16 chan;
+		s64 timestamp __aligned(8);
+	} scan;
+};
+
+static const struct iio_chan_spec lidar_channels[] = {
+	{
+		.type = IIO_DISTANCE,
+		.info_mask_separate =
+			BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+		.scan_index = 0,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = 16,
+			.storagebits = 16,
+		},
+	},
+	IIO_CHAN_SOFT_TIMESTAMP(1),
+};
+
+static int lidar_i2c_xfer(struct lidar_data *data, u8 reg, u8 *val, int len)
+{
+	struct i2c_client *client = data->client;
+	struct i2c_msg msg[2];
+	int ret;
+
+	msg[0].addr = client->addr;
+	msg[0].flags = client->flags | I2C_M_STOP;
+	msg[0].len = 1;
+	msg[0].buf  = (char *) &reg;
+
+	msg[1].addr = client->addr;
+	msg[1].flags = client->flags | I2C_M_RD;
+	msg[1].len = len;
+	msg[1].buf = (char *) val;
+
+	ret = i2c_transfer(client->adapter, msg, 2);
+
+	return (ret == 2) ? 0 : -EIO;
+}
+
+static int lidar_smbus_xfer(struct lidar_data *data, u8 reg, u8 *val, int len)
+{
+	struct i2c_client *client = data->client;
+	int ret;
+
+	/*
+	 * Device needs a STOP condition between address write, and data read
+	 * so in turn i2c_smbus_read_byte_data cannot be used
+	 */
+
+	while (len--) {
+		ret = i2c_smbus_write_byte(client, reg++);
+		if (ret < 0) {
+			dev_err(&client->dev, "cannot write addr value");
+			return ret;
+		}
+
+		ret = i2c_smbus_read_byte(client);
+		if (ret < 0) {
+			dev_err(&client->dev, "cannot read data value");
+			return ret;
+		}
+
+		*(val++) = ret;
+	}
+
+	return 0;
+}
+
+static int lidar_read_byte(struct lidar_data *data, u8 reg)
+{
+	int ret;
+	u8 val;
+
+	ret = data->xfer(data, reg, &val, 1);
+	if (ret < 0)
+		return ret;
+
+	return val;
+}
+
+static inline int lidar_write_control(struct lidar_data *data, int val)
+{
+	return i2c_smbus_write_byte_data(data->client, LIDAR_REG_CONTROL, val);
+}
+
+static inline int lidar_write_power(struct lidar_data *data, int val)
+{
+	return i2c_smbus_write_byte_data(data->client,
+					 LIDAR_REG_PWR_CONTROL, val);
+}
+
+static int lidar_read_measurement(struct lidar_data *data, u16 *reg)
+{
+	__be16 value;
+	int ret = data->xfer(data, LIDAR_REG_DATA_HBYTE |
+			(data->i2c_enabled ? LIDAR_REG_DATA_WORD_READ : 0),
+			(u8 *) &value, 2);
+
+	if (!ret)
+		*reg = be16_to_cpu(value);
+
+	return ret;
+}
+
+static int lidar_get_measurement(struct lidar_data *data, u16 *reg)
+{
+	struct i2c_client *client = data->client;
+	int tries = 10;
+	int ret;
+
+	ret = pm_runtime_resume_and_get(&client->dev);
+	if (ret < 0)
+		return ret;
+
+	/* start sample */
+	ret = lidar_write_control(data, LIDAR_REG_CONTROL_ACQUIRE);
+	if (ret < 0) {
+		dev_err(&client->dev, "cannot send start measurement command");
+		pm_runtime_put_noidle(&client->dev);
+		return ret;
+	}
+
+	while (tries--) {
+		usleep_range(1000, 2000);
+
+		ret = lidar_read_byte(data, LIDAR_REG_STATUS);
+		if (ret < 0)
+			break;
+
+		/* return -EINVAL since laser is likely pointed out of range */
+		if (ret & LIDAR_REG_STATUS_INVALID) {
+			*reg = 0;
+			ret = -EINVAL;
+			break;
+		}
+
+		/* sample ready to read */
+		if (!(ret & LIDAR_REG_STATUS_READY)) {
+			ret = lidar_read_measurement(data, reg);
+			break;
+		}
+		ret = -EIO;
+	}
+	pm_runtime_mark_last_busy(&client->dev);
+	pm_runtime_put_autosuspend(&client->dev);
+
+	return ret;
+}
+
+static int lidar_read_raw(struct iio_dev *indio_dev,
+			  struct iio_chan_spec const *chan,
+			  int *val, int *val2, long mask)
+{
+	struct lidar_data *data = iio_priv(indio_dev);
+	int ret = -EINVAL;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW: {
+		u16 reg;
+
+		if (iio_device_claim_direct_mode(indio_dev))
+			return -EBUSY;
+
+		ret = lidar_get_measurement(data, &reg);
+		if (!ret) {
+			*val = reg;
+			ret = IIO_VAL_INT;
+		}
+		iio_device_release_direct_mode(indio_dev);
+		break;
+	}
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		*val2 = 10000;
+		ret = IIO_VAL_INT_PLUS_MICRO;
+		break;
+	}
+
+	return ret;
+}
+
+static irqreturn_t lidar_trigger_handler(int irq, void *private)
+{
+	struct iio_poll_func *pf = private;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct lidar_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = lidar_get_measurement(data, &data->scan.chan);
+	if (!ret) {
+		iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
+						   iio_get_time_ns(indio_dev));
+	} else if (ret != -EINVAL) {
+		dev_err(&data->client->dev, "cannot read LIDAR measurement");
+	}
+
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static const struct iio_info lidar_info = {
+	.read_raw = lidar_read_raw,
+};
+
+static int lidar_probe(struct i2c_client *client,
+		       const struct i2c_device_id *id)
+{
+	struct lidar_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);
+
+	if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+		data->xfer = lidar_i2c_xfer;
+		data->i2c_enabled = 1;
+	} else if (i2c_check_functionality(client->adapter,
+				I2C_FUNC_SMBUS_WORD_DATA | I2C_FUNC_SMBUS_BYTE))
+		data->xfer = lidar_smbus_xfer;
+	else
+		return -EOPNOTSUPP;
+
+	indio_dev->info = &lidar_info;
+	indio_dev->name = LIDAR_DRV_NAME;
+	indio_dev->channels = lidar_channels;
+	indio_dev->num_channels = ARRAY_SIZE(lidar_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	i2c_set_clientdata(client, indio_dev);
+
+	data->client = client;
+	data->indio_dev = indio_dev;
+
+	ret = iio_triggered_buffer_setup(indio_dev, NULL,
+					 lidar_trigger_handler, NULL);
+	if (ret)
+		return ret;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_unreg_buffer;
+
+	pm_runtime_set_autosuspend_delay(&client->dev, 1000);
+	pm_runtime_use_autosuspend(&client->dev);
+
+	ret = pm_runtime_set_active(&client->dev);
+	if (ret)
+		goto error_unreg_buffer;
+	pm_runtime_enable(&client->dev);
+	pm_runtime_idle(&client->dev);
+
+	return 0;
+
+error_unreg_buffer:
+	iio_triggered_buffer_cleanup(indio_dev);
+
+	return ret;
+}
+
+static void lidar_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+	iio_triggered_buffer_cleanup(indio_dev);
+
+	pm_runtime_disable(&client->dev);
+	pm_runtime_set_suspended(&client->dev);
+}
+
+static const struct i2c_device_id lidar_id[] = {
+	{"lidar-lite-v2", 0},
+	{"lidar-lite-v3", 0},
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, lidar_id);
+
+static const struct of_device_id lidar_dt_ids[] = {
+	{ .compatible = "pulsedlight,lidar-lite-v2" },
+	{ .compatible = "grmn,lidar-lite-v3" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, lidar_dt_ids);
+
+static int lidar_pm_runtime_suspend(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct lidar_data *data = iio_priv(indio_dev);
+
+	return lidar_write_power(data, 0x0f);
+}
+
+static int lidar_pm_runtime_resume(struct device *dev)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev));
+	struct lidar_data *data = iio_priv(indio_dev);
+	int ret = lidar_write_power(data, 0);
+
+	/* regulator and FPGA needs settling time */
+	usleep_range(15000, 20000);
+
+	return ret;
+}
+
+static const struct dev_pm_ops lidar_pm_ops = {
+	RUNTIME_PM_OPS(lidar_pm_runtime_suspend, lidar_pm_runtime_resume, NULL)
+};
+
+static struct i2c_driver lidar_driver = {
+	.driver = {
+		.name	= LIDAR_DRV_NAME,
+		.of_match_table	= lidar_dt_ids,
+		.pm	= pm_ptr(&lidar_pm_ops),
+	},
+	.probe		= lidar_probe,
+	.remove		= lidar_remove,
+	.id_table	= lidar_id,
+};
+module_i2c_driver(lidar_driver);
+
+MODULE_AUTHOR("Matt Ranostay <matt.ranostay@konsulko.com>");
+MODULE_DESCRIPTION("PulsedLight LIDAR sensor");
+MODULE_LICENSE("GPL");