--- /dev/null
+/*
+ * vl6180.c - Support for STMicroelectronics VL6180 ALS, range and proximity
+ * sensor
+ *
+ * Copyright 2017 Peter Meerwald-Stadler <pmeerw@pmeerw.net>
+ * Copyright 2017 Manivannan Sadhasivam <manivannanece23@gmail.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.
+ *
+ * IIO driver for VL6180 (7-bit I2C slave address 0x29)
+ *
+ * Range: 0 to 100mm
+ * ALS: < 1 Lux up to 100 kLux
+ * IR: 850nm
+ *
+ * TODO: irq, threshold events, continuous mode, hardware buffer
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/err.h>
+#include <linux/of.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define VL6180_DRV_NAME "vl6180"
+
+/* Device identification register and value */
+#define VL6180_MODEL_ID 0x000
+#define VL6180_MODEL_ID_VAL 0xb4
+
+/* Configuration registers */
+#define VL6180_INTR_CONFIG 0x014
+#define VL6180_INTR_CLEAR 0x015
+#define VL6180_OUT_OF_RESET 0x016
+#define VL6180_HOLD 0x017
+#define VL6180_RANGE_START 0x018
+#define VL6180_ALS_START 0x038
+#define VL6180_ALS_GAIN 0x03f
+#define VL6180_ALS_IT 0x040
+
+/* Status registers */
+#define VL6180_RANGE_STATUS 0x04d
+#define VL6180_ALS_STATUS 0x04e
+#define VL6180_INTR_STATUS 0x04f
+
+/* Result value registers */
+#define VL6180_ALS_VALUE 0x050
+#define VL6180_RANGE_VALUE 0x062
+#define VL6180_RANGE_RATE 0x066
+
+/* bits of the RANGE_START and ALS_START register */
+#define VL6180_MODE_CONT BIT(1) /* continuous mode */
+#define VL6180_STARTSTOP BIT(0) /* start measurement, auto-reset */
+
+/* bits of the INTR_STATUS and INTR_CONFIG register */
+#define VL6180_ALS_READY BIT(5)
+#define VL6180_RANGE_READY BIT(2)
+
+/* bits of the INTR_CLEAR register */
+#define VL6180_CLEAR_ERROR BIT(2)
+#define VL6180_CLEAR_ALS BIT(1)
+#define VL6180_CLEAR_RANGE BIT(0)
+
+/* bits of the HOLD register */
+#define VL6180_HOLD_ON BIT(0)
+
+/* default value for the ALS_IT register */
+#define VL6180_ALS_IT_100 0x63 /* 100 ms */
+
+/* values for the ALS_GAIN register */
+#define VL6180_ALS_GAIN_1 0x46
+#define VL6180_ALS_GAIN_1_25 0x45
+#define VL6180_ALS_GAIN_1_67 0x44
+#define VL6180_ALS_GAIN_2_5 0x43
+#define VL6180_ALS_GAIN_5 0x42
+#define VL6180_ALS_GAIN_10 0x41
+#define VL6180_ALS_GAIN_20 0x40
+#define VL6180_ALS_GAIN_40 0x47
+
+struct vl6180_data {
+ struct i2c_client *client;
+ struct mutex lock;
+};
+
+enum { VL6180_ALS, VL6180_RANGE, VL6180_PROX };
+
+/**
+ * struct vl6180_chan_regs - Registers for accessing channels
+ * @drdy_mask: Data ready bit in status register
+ * @start_reg: Conversion start register
+ * @value_reg: Result value register
+ * @word: Register word length
+ */
+struct vl6180_chan_regs {
+ u8 drdy_mask;
+ u16 start_reg, value_reg;
+ bool word;
+};
+
+static const struct vl6180_chan_regs vl6180_chan_regs_table[] = {
+ [VL6180_ALS] = {
+ .drdy_mask = VL6180_ALS_READY,
+ .start_reg = VL6180_ALS_START,
+ .value_reg = VL6180_ALS_VALUE,
+ .word = true,
+ },
+ [VL6180_RANGE] = {
+ .drdy_mask = VL6180_RANGE_READY,
+ .start_reg = VL6180_RANGE_START,
+ .value_reg = VL6180_RANGE_VALUE,
+ .word = false,
+ },
+ [VL6180_PROX] = {
+ .drdy_mask = VL6180_RANGE_READY,
+ .start_reg = VL6180_RANGE_START,
+ .value_reg = VL6180_RANGE_RATE,
+ .word = true,
+ },
+};
+
+static int vl6180_read(struct i2c_client *client, u16 cmd, void *databuf,
+ u8 len)
+{
+ __be16 cmdbuf = cpu_to_be16(cmd);
+ struct i2c_msg msgs[2] = {
+ { .addr = client->addr, .len = sizeof(cmdbuf), .buf = (u8 *) &cmdbuf },
+ { .addr = client->addr, .len = len, .buf = databuf,
+ .flags = I2C_M_RD } };
+ int ret;
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0)
+ dev_err(&client->dev, "failed reading register 0x%04x\n", cmd);
+
+ return ret;
+}
+
+static int vl6180_read_byte(struct i2c_client *client, u16 cmd)
+{
+ u8 data;
+ int ret;
+
+ ret = vl6180_read(client, cmd, &data, sizeof(data));
+ if (ret < 0)
+ return ret;
+
+ return data;
+}
+
+static int vl6180_read_word(struct i2c_client *client, u16 cmd)
+{
+ __be16 data;
+ int ret;
+
+ ret = vl6180_read(client, cmd, &data, sizeof(data));
+ if (ret < 0)
+ return ret;
+
+ return be16_to_cpu(data);
+}
+
+static int vl6180_write_byte(struct i2c_client *client, u16 cmd, u8 val)
+{
+ u8 buf[3];
+ struct i2c_msg msgs[1] = {
+ { .addr = client->addr, .len = sizeof(buf), .buf = (u8 *) &buf } };
+ int ret;
+
+ buf[0] = cmd >> 8;
+ buf[1] = cmd & 0xff;
+ buf[2] = val;
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0) {
+ dev_err(&client->dev, "failed writing register 0x%04x\n", cmd);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int vl6180_write_word(struct i2c_client *client, u16 cmd, u16 val)
+{
+ __be16 buf[2];
+ struct i2c_msg msgs[1] = {
+ { .addr = client->addr, .len = sizeof(buf), .buf = (u8 *) &buf } };
+ int ret;
+
+ buf[0] = cpu_to_be16(cmd);
+ buf[1] = cpu_to_be16(val);
+
+ ret = i2c_transfer(client->adapter, msgs, ARRAY_SIZE(msgs));
+ if (ret < 0) {
+ dev_err(&client->dev, "failed writing register 0x%04x\n", cmd);
+ return ret;
+ }
+
+ return 0;
+}
+
+static int vl6180_measure(struct vl6180_data *data, int addr)
+{
+ struct i2c_client *client = data->client;
+ int tries = 20, ret;
+ u16 value;
+
+ mutex_lock(&data->lock);
+ /* Start single shot measurement */
+ ret = vl6180_write_byte(client,
+ vl6180_chan_regs_table[addr].start_reg, VL6180_STARTSTOP);
+ if (ret < 0)
+ goto fail;
+
+ while (tries--) {
+ ret = vl6180_read_byte(client, VL6180_INTR_STATUS);
+ if (ret < 0)
+ goto fail;
+
+ if (ret & vl6180_chan_regs_table[addr].drdy_mask)
+ break;
+ msleep(20);
+ }
+
+ if (tries < 0) {
+ ret = -EIO;
+ goto fail;
+ }
+
+ /* Read result value from appropriate registers */
+ ret = vl6180_chan_regs_table[addr].word ?
+ vl6180_read_word(client, vl6180_chan_regs_table[addr].value_reg) :
+ vl6180_read_byte(client, vl6180_chan_regs_table[addr].value_reg);
+ if (ret < 0)
+ goto fail;
+ value = ret;
+
+ /* Clear the interrupt flag after data read */
+ ret = vl6180_write_byte(client, VL6180_INTR_CLEAR,
+ VL6180_CLEAR_ERROR | VL6180_CLEAR_ALS | VL6180_CLEAR_RANGE);
+ if (ret < 0)
+ goto fail;
+
+ ret = value;
+
+fail:
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static const struct iio_chan_spec vl6180_channels[] = {
+ {
+ .type = IIO_LIGHT,
+ .address = VL6180_ALS,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_INT_TIME) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_HARDWAREGAIN),
+ }, {
+ .type = IIO_DISTANCE,
+ .address = VL6180_RANGE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ }, {
+ .type = IIO_PROXIMITY,
+ .address = VL6180_PROX,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ }
+};
+
+/*
+ * Columns 3 & 4 represent the same value in decimal and hex notations.
+ * Kept in order to avoid the datatype conversion while reading the
+ * hardware_gain.
+ */
+static const int vl6180_als_gain[8][4] = {
+ { 1, 0, 70, VL6180_ALS_GAIN_1 },
+ { 1, 250000, 69, VL6180_ALS_GAIN_1_25 },
+ { 1, 670000, 68, VL6180_ALS_GAIN_1_67 },
+ { 2, 500000, 67, VL6180_ALS_GAIN_2_5 },
+ { 5, 0, 66, VL6180_ALS_GAIN_5 },
+ { 10, 0, 65, VL6180_ALS_GAIN_10 },
+ { 20, 0, 64, VL6180_ALS_GAIN_20 },
+ { 40, 0, 71, VL6180_ALS_GAIN_40 }
+};
+
+static int vl6180_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct vl6180_data *data = iio_priv(indio_dev);
+ int ret, i;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = vl6180_measure(data, chan->address);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_INT_TIME:
+ ret = vl6180_read_word(data->client, VL6180_ALS_IT);
+ if (ret < 0)
+ return ret;
+ *val = 0; /* 1 count = 1ms (0 = 1ms) */
+ *val2 = (ret + 1) * 1000; /* convert to seconds */
+
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->type) {
+ case IIO_LIGHT:
+ *val = 0; /* one ALS count is 0.32 Lux */
+ *val2 = 320000;
+ break;
+ case IIO_DISTANCE:
+ *val = 0; /* sensor reports mm, scale to meter */
+ *val2 = 1000;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ ret = vl6180_read_byte(data->client, VL6180_ALS_GAIN);
+ if (ret < 0)
+ return -EINVAL;
+ for (i = 0; i < ARRAY_SIZE(vl6180_als_gain); i++) {
+ if (ret == vl6180_als_gain[i][2]) {
+ *val = vl6180_als_gain[i][0];
+ *val2 = vl6180_als_gain[i][1];
+ }
+ }
+
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static IIO_CONST_ATTR(als_gain_available, "1 1.25 1.67 2.5 5 10 20 40");
+
+static struct attribute *vl6180_attributes[] = {
+ &iio_const_attr_als_gain_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group vl6180_attribute_group = {
+ .attrs = vl6180_attributes,
+};
+
+/* HOLD is needed before updating any config registers */
+static int vl6180_hold(struct vl6180_data *data, bool hold)
+{
+ return vl6180_write_byte(data->client, VL6180_HOLD,
+ hold ? VL6180_HOLD_ON : 0);
+}
+
+static int vl6180_set_als_gain(struct vl6180_data *data, int val, int val2)
+{
+ int i, ret;
+
+ for (i = 0; i < ARRAY_SIZE(vl6180_als_gain); i++) {
+ if (val == vl6180_als_gain[i][0] &&
+ val2 == vl6180_als_gain[i][1]) {
+ mutex_lock(&data->lock);
+ ret = vl6180_hold(data, true);
+ if (ret < 0)
+ goto fail;
+ ret = vl6180_write_byte(data->client, VL6180_ALS_GAIN,
+ vl6180_als_gain[i][3]);
+fail:
+ vl6180_hold(data, false);
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static int vl6180_set_it(struct vl6180_data *data, int val2)
+{
+ int ret;
+
+ mutex_lock(&data->lock);
+ ret = vl6180_hold(data, true);
+ if (ret < 0)
+ goto fail;
+ ret = vl6180_write_word(data->client, VL6180_ALS_IT,
+ (val2 - 500) / 1000); /* write value in ms */
+fail:
+ vl6180_hold(data, false);
+ mutex_unlock(&data->lock);
+
+ return ret;
+}
+
+static int vl6180_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct vl6180_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_INT_TIME:
+ if (val != 0 || val2 < 500 || val2 >= 512500)
+ return -EINVAL;
+
+ return vl6180_set_it(data, val2);
+ case IIO_CHAN_INFO_HARDWAREGAIN:
+ if (chan->type != IIO_LIGHT)
+ return -EINVAL;
+
+ return vl6180_set_als_gain(data, val, val2);
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info vl6180_info = {
+ .read_raw = vl6180_read_raw,
+ .write_raw = vl6180_write_raw,
+ .attrs = &vl6180_attribute_group,
+ .driver_module = THIS_MODULE,
+};
+
+static int vl6180_init(struct vl6180_data *data)
+{
+ struct i2c_client *client = data->client;
+ int ret;
+
+ ret = vl6180_read_byte(client, VL6180_MODEL_ID);
+ if (ret < 0)
+ return ret;
+
+ if (ret != VL6180_MODEL_ID_VAL) {
+ dev_err(&client->dev, "invalid model ID %02x\n", ret);
+ return -ENODEV;
+ }
+
+ ret = vl6180_hold(data, true);
+ if (ret < 0)
+ return ret;
+
+ ret = vl6180_read_byte(client, VL6180_OUT_OF_RESET);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Detect false reset condition here. This bit is always set when the
+ * system comes out of reset.
+ */
+ if (ret != 0x01)
+ dev_info(&client->dev, "device is not fresh out of reset\n");
+
+ /* Enable ALS and Range ready interrupts */
+ ret = vl6180_write_byte(client, VL6180_INTR_CONFIG,
+ VL6180_ALS_READY | VL6180_RANGE_READY);
+ if (ret < 0)
+ return ret;
+
+ /* ALS integration time: 100ms */
+ ret = vl6180_write_word(client, VL6180_ALS_IT, VL6180_ALS_IT_100);
+ if (ret < 0)
+ return ret;
+
+ /* ALS gain: 1 */
+ ret = vl6180_write_byte(client, VL6180_ALS_GAIN, VL6180_ALS_GAIN_1);
+ if (ret < 0)
+ return ret;
+
+ ret = vl6180_write_byte(client, VL6180_OUT_OF_RESET, 0x00);
+ if (ret < 0)
+ return ret;
+
+ return vl6180_hold(data, false);
+}
+
+static int vl6180_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct vl6180_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;
+ mutex_init(&data->lock);
+
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &vl6180_info;
+ indio_dev->channels = vl6180_channels;
+ indio_dev->num_channels = ARRAY_SIZE(vl6180_channels);
+ indio_dev->name = VL6180_DRV_NAME;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = vl6180_init(data);
+ if (ret < 0)
+ return ret;
+
+ return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct of_device_id vl6180_of_match[] = {
+ { .compatible = "st,vl6180", },
+ { },
+};
+MODULE_DEVICE_TABLE(of, vl6180_of_match);
+
+static const struct i2c_device_id vl6180_id[] = {
+ { "vl6180", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, vl6180_id);
+
+static struct i2c_driver vl6180_driver = {
+ .driver = {
+ .name = VL6180_DRV_NAME,
+ .of_match_table = of_match_ptr(vl6180_of_match),
+ },
+ .probe = vl6180_probe,
+ .id_table = vl6180_id,
+};
+
+module_i2c_driver(vl6180_driver);
+
+MODULE_AUTHOR("Peter Meerwald-Stadler <pmeerw@pmeerw.net>");
+MODULE_AUTHOR("Manivannan Sadhasivam <manivannanece23@gmail.com>");
+MODULE_DESCRIPTION("STMicro VL6180 ALS, range and proximity sensor driver");
+MODULE_LICENSE("GPL");
projects / platform / kernel / linux-rpi.git / commitdiff