--- /dev/null
+/*
+ * zopt2201.c - Support for IDT ZOPT2201 ambient light and UV B sensor
+ *
+ * Copyright 2017 Peter Meerwald-Stadler <pmeerw@pmeerw.net>
+ *
+ * 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.
+ *
+ * Datasheet: https://www.idt.com/document/dst/zopt2201-datasheet
+ * 7-bit I2C slave addresses 0x53 (default) or 0x52 (programmed)
+ *
+ * TODO: interrupt support, ALS/UVB raw mode
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/mutex.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+
+#define ZOPT2201_DRV_NAME "zopt2201"
+
+/* Registers */
+#define ZOPT2201_MAIN_CTRL 0x00
+#define ZOPT2201_LS_MEAS_RATE 0x04
+#define ZOPT2201_LS_GAIN 0x05
+#define ZOPT2201_PART_ID 0x06
+#define ZOPT2201_MAIN_STATUS 0x07
+#define ZOPT2201_ALS_DATA 0x0d /* LSB first, 13 to 20 bits */
+#define ZOPT2201_UVB_DATA 0x10 /* LSB first, 13 to 20 bits */
+#define ZOPT2201_UV_COMP_DATA 0x13 /* LSB first, 13 to 20 bits */
+#define ZOPT2201_COMP_DATA 0x16 /* LSB first, 13 to 20 bits */
+#define ZOPT2201_INT_CFG 0x19
+#define ZOPT2201_INT_PST 0x1a
+
+#define ZOPT2201_MAIN_CTRL_LS_MODE BIT(3) /* 0 .. ALS, 1 .. UV B */
+#define ZOPT2201_MAIN_CTRL_LS_EN BIT(1)
+
+/* Values for ZOPT2201_LS_MEAS_RATE resolution / bit width */
+#define ZOPT2201_MEAS_RES_20BIT 0 /* takes 400 ms */
+#define ZOPT2201_MEAS_RES_19BIT 1 /* takes 200 ms */
+#define ZOPT2201_MEAS_RES_18BIT 2 /* takes 100 ms, default */
+#define ZOPT2201_MEAS_RES_17BIT 3 /* takes 50 ms */
+#define ZOPT2201_MEAS_RES_16BIT 4 /* takes 25 ms */
+#define ZOPT2201_MEAS_RES_13BIT 5 /* takes 3.125 ms */
+#define ZOPT2201_MEAS_RES_SHIFT 4
+
+/* Values for ZOPT2201_LS_MEAS_RATE measurement rate */
+#define ZOPT2201_MEAS_FREQ_25MS 0
+#define ZOPT2201_MEAS_FREQ_50MS 1
+#define ZOPT2201_MEAS_FREQ_100MS 2 /* default */
+#define ZOPT2201_MEAS_FREQ_200MS 3
+#define ZOPT2201_MEAS_FREQ_500MS 4
+#define ZOPT2201_MEAS_FREQ_1000MS 5
+#define ZOPT2201_MEAS_FREQ_2000MS 6
+
+/* Values for ZOPT2201_LS_GAIN */
+#define ZOPT2201_LS_GAIN_1 0
+#define ZOPT2201_LS_GAIN_3 1
+#define ZOPT2201_LS_GAIN_6 2
+#define ZOPT2201_LS_GAIN_9 3
+#define ZOPT2201_LS_GAIN_18 4
+
+/* Values for ZOPT2201_MAIN_STATUS */
+#define ZOPT2201_MAIN_STATUS_POWERON BIT(5)
+#define ZOPT2201_MAIN_STATUS_INT BIT(4)
+#define ZOPT2201_MAIN_STATUS_DRDY BIT(3)
+
+#define ZOPT2201_PART_NUMBER 0xb2
+
+struct zopt2201_data {
+ struct i2c_client *client;
+ struct mutex lock;
+ u8 gain;
+ u8 res;
+ u8 rate;
+};
+
+static const struct {
+ unsigned int gain; /* gain factor */
+ unsigned int scale; /* micro lux per count */
+} zopt2201_gain_als[] = {
+ { 1, 19200000 },
+ { 3, 6400000 },
+ { 6, 3200000 },
+ { 9, 2133333 },
+ { 18, 1066666 },
+};
+
+static const struct {
+ unsigned int gain; /* gain factor */
+ unsigned int scale; /* micro W/m2 per count */
+} zopt2201_gain_uvb[] = {
+ { 1, 460800 },
+ { 3, 153600 },
+ { 6, 76800 },
+ { 9, 51200 },
+ { 18, 25600 },
+};
+
+static const struct {
+ unsigned int bits; /* sensor resolution in bits */
+ unsigned long us; /* measurement time in micro seconds */
+} zopt2201_resolution[] = {
+ { 20, 400000 },
+ { 19, 200000 },
+ { 18, 100000 },
+ { 17, 50000 },
+ { 16, 25000 },
+ { 13, 3125 },
+};
+
+static const struct {
+ unsigned int scale, uscale; /* scale factor as integer + micro */
+ u8 gain; /* gain register value */
+ u8 res; /* resolution register value */
+} zopt2201_scale_als[] = {
+ { 19, 200000, 0, 5 },
+ { 6, 400000, 1, 5 },
+ { 3, 200000, 2, 5 },
+ { 2, 400000, 0, 4 },
+ { 2, 133333, 3, 5 },
+ { 1, 200000, 0, 3 },
+ { 1, 66666, 4, 5 },
+ { 0, 800000, 1, 4 },
+ { 0, 600000, 0, 2 },
+ { 0, 400000, 2, 4 },
+ { 0, 300000, 0, 1 },
+ { 0, 266666, 3, 4 },
+ { 0, 200000, 2, 3 },
+ { 0, 150000, 0, 0 },
+ { 0, 133333, 4, 4 },
+ { 0, 100000, 2, 2 },
+ { 0, 66666, 4, 3 },
+ { 0, 50000, 2, 1 },
+ { 0, 33333, 4, 2 },
+ { 0, 25000, 2, 0 },
+ { 0, 16666, 4, 1 },
+ { 0, 8333, 4, 0 },
+};
+
+static const struct {
+ unsigned int scale, uscale; /* scale factor as integer + micro */
+ u8 gain; /* gain register value */
+ u8 res; /* resolution register value */
+} zopt2201_scale_uvb[] = {
+ { 0, 460800, 0, 5 },
+ { 0, 153600, 1, 5 },
+ { 0, 76800, 2, 5 },
+ { 0, 57600, 0, 4 },
+ { 0, 51200, 3, 5 },
+ { 0, 28800, 0, 3 },
+ { 0, 25600, 4, 5 },
+ { 0, 19200, 1, 4 },
+ { 0, 14400, 0, 2 },
+ { 0, 9600, 2, 4 },
+ { 0, 7200, 0, 1 },
+ { 0, 6400, 3, 4 },
+ { 0, 4800, 2, 3 },
+ { 0, 3600, 0, 0 },
+ { 0, 3200, 4, 4 },
+ { 0, 2400, 2, 2 },
+ { 0, 1600, 4, 3 },
+ { 0, 1200, 2, 1 },
+ { 0, 800, 4, 2 },
+ { 0, 600, 2, 0 },
+ { 0, 400, 4, 1 },
+ { 0, 200, 4, 0 },
+};
+
+static int zopt2201_enable_mode(struct zopt2201_data *data, bool uvb_mode)
+{
+ u8 out = ZOPT2201_MAIN_CTRL_LS_EN;
+
+ if (uvb_mode)
+ out |= ZOPT2201_MAIN_CTRL_LS_MODE;
+
+ return i2c_smbus_write_byte_data(data->client, ZOPT2201_MAIN_CTRL, out);
+}
+
+static int zopt2201_read(struct zopt2201_data *data, u8 reg)
+{
+ struct i2c_client *client = data->client;
+ int tries = 10;
+ u8 buf[3];
+ int ret;
+
+ mutex_lock(&data->lock);
+ ret = zopt2201_enable_mode(data, reg == ZOPT2201_UVB_DATA);
+ if (ret < 0)
+ goto fail;
+
+ while (tries--) {
+ unsigned long t = zopt2201_resolution[data->res].us;
+
+ if (t <= 20000)
+ usleep_range(t, t + 1000);
+ else
+ msleep(t / 1000);
+ ret = i2c_smbus_read_byte_data(client, ZOPT2201_MAIN_STATUS);
+ if (ret < 0)
+ goto fail;
+ if (ret & ZOPT2201_MAIN_STATUS_DRDY)
+ break;
+ }
+
+ if (tries < 0) {
+ ret = -ETIMEDOUT;
+ goto fail;
+ }
+
+ ret = i2c_smbus_read_i2c_block_data(client, reg, sizeof(buf), buf);
+ if (ret < 0)
+ goto fail;
+
+ ret = i2c_smbus_write_byte_data(client, ZOPT2201_MAIN_CTRL, 0x00);
+ if (ret < 0)
+ goto fail;
+ mutex_unlock(&data->lock);
+
+ return (buf[2] << 16) | (buf[1] << 8) | buf[0];
+
+fail:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static const struct iio_chan_spec zopt2201_channels[] = {
+ {
+ .type = IIO_LIGHT,
+ .address = ZOPT2201_ALS_DATA,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
+ },
+ {
+ .type = IIO_INTENSITY,
+ .modified = 1,
+ .channel2 = IIO_MOD_LIGHT_UV,
+ .address = ZOPT2201_UVB_DATA,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
+ },
+ {
+ .type = IIO_UVINDEX,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
+ },
+};
+
+static int zopt2201_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct zopt2201_data *data = iio_priv(indio_dev);
+ u64 tmp;
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = zopt2201_read(data, chan->address);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_PROCESSED:
+ ret = zopt2201_read(data, ZOPT2201_UVB_DATA);
+ if (ret < 0)
+ return ret;
+ *val = ret * 18 *
+ (1 << (20 - zopt2201_resolution[data->res].bits)) /
+ zopt2201_gain_uvb[data->gain].gain;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->address) {
+ case ZOPT2201_ALS_DATA:
+ *val = zopt2201_gain_als[data->gain].scale;
+ break;
+ case ZOPT2201_UVB_DATA:
+ *val = zopt2201_gain_uvb[data->gain].scale;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ *val2 = 1000000;
+ *val2 *= (1 << (zopt2201_resolution[data->res].bits - 13));
+ tmp = div_s64(*val * 1000000ULL, *val2);
+ *val = div_s64_rem(tmp, 1000000, val2);
+
+ return IIO_VAL_INT_PLUS_MICRO;
+ case IIO_CHAN_INFO_INT_TIME:
+ *val = 0;
+ *val2 = zopt2201_resolution[data->res].us;
+ return IIO_VAL_INT_PLUS_MICRO;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int zopt2201_set_resolution(struct zopt2201_data *data, u8 res)
+{
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(data->client, ZOPT2201_LS_MEAS_RATE,
+ (res << ZOPT2201_MEAS_RES_SHIFT) |
+ data->rate);
+ if (ret < 0)
+ return ret;
+
+ data->res = res;
+
+ return 0;
+}
+
+static int zopt2201_write_resolution(struct zopt2201_data *data,
+ int val, int val2)
+{
+ int i, ret;
+
+ if (val != 0)
+ return -EINVAL;
+
+ for (i = 0; i < ARRAY_SIZE(zopt2201_resolution); i++)
+ if (val2 == zopt2201_resolution[i].us) {
+ mutex_lock(&data->lock);
+ ret = zopt2201_set_resolution(data, i);
+ mutex_unlock(&data->lock);
+ return ret;
+ }
+
+ return -EINVAL;
+}
+
+static int zopt2201_set_gain(struct zopt2201_data *data, u8 gain)
+{
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(data->client, ZOPT2201_LS_GAIN, gain);
+ if (ret < 0)
+ return ret;
+
+ data->gain = gain;
+
+ return 0;
+}
+
+static int zopt2201_write_scale_als_by_idx(struct zopt2201_data *data, int idx)
+{
+ int ret;
+
+ mutex_lock(&data->lock);
+ ret = zopt2201_set_resolution(data, zopt2201_scale_als[idx].res);
+ if (ret < 0)
+ goto unlock;
+
+ ret = zopt2201_set_gain(data, zopt2201_scale_als[idx].gain);
+
+unlock:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int zopt2201_write_scale_als(struct zopt2201_data *data,
+ int val, int val2)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(zopt2201_scale_als); i++)
+ if (val == zopt2201_scale_als[i].scale &&
+ val2 == zopt2201_scale_als[i].uscale) {
+ return zopt2201_write_scale_als_by_idx(data, i);
+ }
+
+ return -EINVAL;
+}
+
+static int zopt2201_write_scale_uvb_by_idx(struct zopt2201_data *data, int idx)
+{
+ int ret;
+
+ mutex_lock(&data->lock);
+ ret = zopt2201_set_resolution(data, zopt2201_scale_als[idx].res);
+ if (ret < 0)
+ goto unlock;
+
+ ret = zopt2201_set_gain(data, zopt2201_scale_als[idx].gain);
+
+unlock:
+ mutex_unlock(&data->lock);
+ return ret;
+}
+
+static int zopt2201_write_scale_uvb(struct zopt2201_data *data,
+ int val, int val2)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(zopt2201_scale_uvb); i++)
+ if (val == zopt2201_scale_uvb[i].scale &&
+ val2 == zopt2201_scale_uvb[i].uscale)
+ return zopt2201_write_scale_uvb_by_idx(data, i);
+
+ return -EINVAL;
+}
+
+static int zopt2201_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct zopt2201_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_INT_TIME:
+ return zopt2201_write_resolution(data, val, val2);
+ case IIO_CHAN_INFO_SCALE:
+ switch (chan->address) {
+ case ZOPT2201_ALS_DATA:
+ return zopt2201_write_scale_als(data, val, val2);
+ case ZOPT2201_UVB_DATA:
+ return zopt2201_write_scale_uvb(data, val, val2);
+ default:
+ return -EINVAL;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static ssize_t zopt2201_show_int_time_available(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ size_t len = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(zopt2201_resolution); i++)
+ len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06lu ",
+ zopt2201_resolution[i].us);
+ buf[len - 1] = '\n';
+
+ return len;
+}
+
+static IIO_DEV_ATTR_INT_TIME_AVAIL(zopt2201_show_int_time_available);
+
+static ssize_t zopt2201_show_als_scale_avail(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ ssize_t len = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(zopt2201_scale_als); i++)
+ len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ",
+ zopt2201_scale_als[i].scale,
+ zopt2201_scale_als[i].uscale);
+ buf[len - 1] = '\n';
+
+ return len;
+}
+
+static ssize_t zopt2201_show_uvb_scale_avail(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ ssize_t len = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(zopt2201_scale_uvb); i++)
+ len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ",
+ zopt2201_scale_uvb[i].scale,
+ zopt2201_scale_uvb[i].uscale);
+ buf[len - 1] = '\n';
+
+ return len;
+}
+
+static IIO_DEVICE_ATTR(in_illuminance_scale_available, 0444,
+ zopt2201_show_als_scale_avail, NULL, 0);
+static IIO_DEVICE_ATTR(in_intensity_uv_scale_available, 0444,
+ zopt2201_show_uvb_scale_avail, NULL, 0);
+
+static struct attribute *zopt2201_attributes[] = {
+ &iio_dev_attr_integration_time_available.dev_attr.attr,
+ &iio_dev_attr_in_illuminance_scale_available.dev_attr.attr,
+ &iio_dev_attr_in_intensity_uv_scale_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group zopt2201_attribute_group = {
+ .attrs = zopt2201_attributes,
+};
+
+static const struct iio_info zopt2201_info = {
+ .read_raw = zopt2201_read_raw,
+ .write_raw = zopt2201_write_raw,
+ .attrs = &zopt2201_attribute_group,
+};
+
+static int zopt2201_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct zopt2201_data *data;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_I2C_BLOCK))
+ return -EOPNOTSUPP;
+
+ ret = i2c_smbus_read_byte_data(client, ZOPT2201_PART_ID);
+ if (ret < 0)
+ return ret;
+ if (ret != ZOPT2201_PART_NUMBER)
+ return -ENODEV;
+
+ 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 = &zopt2201_info;
+ indio_dev->channels = zopt2201_channels;
+ indio_dev->num_channels = ARRAY_SIZE(zopt2201_channels);
+ indio_dev->name = ZOPT2201_DRV_NAME;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ data->rate = ZOPT2201_MEAS_FREQ_100MS;
+ ret = zopt2201_set_resolution(data, ZOPT2201_MEAS_RES_18BIT);
+ if (ret < 0)
+ return ret;
+
+ ret = zopt2201_set_gain(data, ZOPT2201_LS_GAIN_3);
+ if (ret < 0)
+ return ret;
+
+ return devm_iio_device_register(&client->dev, indio_dev);
+}
+
+static const struct i2c_device_id zopt2201_id[] = {
+ { "zopt2201", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, zopt2201_id);
+
+static struct i2c_driver zopt2201_driver = {
+ .driver = {
+ .name = ZOPT2201_DRV_NAME,
+ },
+ .probe = zopt2201_probe,
+ .id_table = zopt2201_id,
+};
+
+module_i2c_driver(zopt2201_driver);
+
+MODULE_AUTHOR("Peter Meerwald-Stadler <pmeerw@pmeerw.net>");
+MODULE_DESCRIPTION("IDT ZOPT2201 ambient light and UV B sensor driver");
+MODULE_LICENSE("GPL");
projects / platform / kernel / linux-rpi.git / commitdiff