--- /dev/null
+/*
+ * isl29125.c - Support for Intersil ISL29125 RGB light sensor
+ *
+ * Copyright (c) 2014 Peter Meerwald <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.
+ *
+ * RGB light sensor with 16-bit channels for red, green, blue);
+ * 7-bit I2C slave address 0x44
+ *
+ * TODO: interrupt support, IR compensation, thresholds, 12bit
+ */
+
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+#include <linux/pm.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/triggered_buffer.h>
+
+#define ISL29125_DRV_NAME "isl29125"
+
+#define ISL29125_DEVICE_ID 0x00
+#define ISL29125_CONF1 0x01
+#define ISL29125_CONF2 0x02
+#define ISL29125_CONF3 0x03
+#define ISL29125_STATUS 0x08
+#define ISL29125_GREEN_DATA 0x09
+#define ISL29125_RED_DATA 0x0b
+#define ISL29125_BLUE_DATA 0x0d
+
+#define ISL29125_ID 0x7d
+
+#define ISL29125_MODE_MASK GENMASK(2, 0)
+#define ISL29125_MODE_PD 0x0
+#define ISL29125_MODE_G 0x1
+#define ISL29125_MODE_R 0x2
+#define ISL29125_MODE_B 0x3
+#define ISL29125_MODE_RGB 0x5
+
+#define ISL29125_MODE_RANGE BIT(3)
+
+#define ISL29125_STATUS_CONV BIT(1)
+
+struct isl29125_data {
+ struct i2c_client *client;
+ struct mutex lock;
+ u8 conf1;
+ u16 buffer[8]; /* 3x 16-bit, padding, 8 bytes timestamp */
+};
+
+#define ISL29125_CHANNEL(_color, _si) { \
+ .type = IIO_INTENSITY, \
+ .modified = 1, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .channel2 = IIO_MOD_LIGHT_##_color, \
+ .scan_index = _si, \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 16, \
+ .storagebits = 16, \
+ .endianness = IIO_CPU, \
+ }, \
+}
+
+static const struct iio_chan_spec isl29125_channels[] = {
+ ISL29125_CHANNEL(GREEN, 0),
+ ISL29125_CHANNEL(RED, 1),
+ ISL29125_CHANNEL(BLUE, 2),
+ IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
+static const struct {
+ u8 mode, data;
+} isl29125_regs[] = {
+ {ISL29125_MODE_G, ISL29125_GREEN_DATA},
+ {ISL29125_MODE_R, ISL29125_RED_DATA},
+ {ISL29125_MODE_B, ISL29125_BLUE_DATA},
+};
+
+static int isl29125_read_data(struct isl29125_data *data, int si)
+{
+ int tries = 5;
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+ data->conf1 | isl29125_regs[si].mode);
+ if (ret < 0)
+ return ret;
+
+ msleep(101);
+
+ while (tries--) {
+ ret = i2c_smbus_read_byte_data(data->client, ISL29125_STATUS);
+ if (ret < 0)
+ goto fail;
+ if (ret & ISL29125_STATUS_CONV)
+ break;
+ msleep(20);
+ }
+
+ if (tries < 0) {
+ dev_err(&data->client->dev, "data not ready\n");
+ ret = -EIO;
+ goto fail;
+ }
+
+ ret = i2c_smbus_read_word_data(data->client, isl29125_regs[si].data);
+
+fail:
+ i2c_smbus_write_byte_data(data->client, ISL29125_CONF1, data->conf1);
+ return ret;
+}
+
+static int isl29125_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct isl29125_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ if (iio_buffer_enabled(indio_dev))
+ return -EBUSY;
+ mutex_lock(&data->lock);
+ ret = isl29125_read_data(data, chan->scan_index);
+ mutex_unlock(&data->lock);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ *val = 0;
+ if (data->conf1 & ISL29125_MODE_RANGE)
+ *val2 = 152590; /* 10k lux full range */
+ else
+ *val2 = 5722; /* 375 lux full range */
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ return -EINVAL;
+}
+
+static int isl29125_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct isl29125_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_SCALE:
+ if (val != 0)
+ return -EINVAL;
+ if (val2 == 152590)
+ data->conf1 |= ISL29125_MODE_RANGE;
+ else if (val2 == 5722)
+ data->conf1 &= ~ISL29125_MODE_RANGE;
+ else
+ return -EINVAL;
+ return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+ data->conf1);
+ default:
+ return -EINVAL;
+ }
+}
+
+static irqreturn_t isl29125_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct isl29125_data *data = iio_priv(indio_dev);
+ int i, j = 0;
+
+ for_each_set_bit(i, indio_dev->active_scan_mask,
+ indio_dev->masklength) {
+ int ret = i2c_smbus_read_word_data(data->client,
+ isl29125_regs[i].data);
+ if (ret < 0)
+ goto done;
+
+ data->buffer[j++] = ret;
+ }
+
+ iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+ iio_get_time_ns());
+
+done:
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static const struct iio_info isl29125_info = {
+ .read_raw = isl29125_read_raw,
+ .write_raw = isl29125_write_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static int isl29125_buffer_preenable(struct iio_dev *indio_dev)
+{
+ struct isl29125_data *data = iio_priv(indio_dev);
+
+ data->conf1 |= ISL29125_MODE_RGB;
+ return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+ data->conf1);
+}
+
+static int isl29125_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct isl29125_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = iio_triggered_buffer_predisable(indio_dev);
+ if (ret < 0)
+ return ret;
+
+ data->conf1 &= ~ISL29125_MODE_MASK;
+ data->conf1 |= ISL29125_MODE_PD;
+ return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+ data->conf1);
+}
+
+static const struct iio_buffer_setup_ops isl29125_buffer_setup_ops = {
+ .preenable = isl29125_buffer_preenable,
+ .postenable = &iio_triggered_buffer_postenable,
+ .predisable = isl29125_buffer_predisable,
+};
+
+static int isl29125_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct isl29125_data *data;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (indio_dev == NULL)
+ 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 = &isl29125_info;
+ indio_dev->name = ISL29125_DRV_NAME;
+ indio_dev->channels = isl29125_channels;
+ indio_dev->num_channels = ARRAY_SIZE(isl29125_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = i2c_smbus_read_byte_data(data->client, ISL29125_DEVICE_ID);
+ if (ret < 0)
+ return ret;
+ if (ret != ISL29125_ID)
+ return -ENODEV;
+
+ data->conf1 = ISL29125_MODE_PD | ISL29125_MODE_RANGE;
+ ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+ data->conf1);
+ if (ret < 0)
+ return ret;
+
+ ret = i2c_smbus_write_byte_data(data->client, ISL29125_STATUS, 0);
+ if (ret < 0)
+ return ret;
+
+ ret = iio_triggered_buffer_setup(indio_dev, NULL,
+ isl29125_trigger_handler, &isl29125_buffer_setup_ops);
+ if (ret < 0)
+ return ret;
+
+ ret = iio_device_register(indio_dev);
+ if (ret < 0)
+ goto buffer_cleanup;
+
+ return 0;
+
+buffer_cleanup:
+ iio_triggered_buffer_cleanup(indio_dev);
+ return ret;
+}
+
+static int isl29125_powerdown(struct isl29125_data *data)
+{
+ return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+ (data->conf1 & ~ISL29125_MODE_MASK) | ISL29125_MODE_PD);
+}
+
+static int isl29125_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);
+ isl29125_powerdown(iio_priv(indio_dev));
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int isl29125_suspend(struct device *dev)
+{
+ struct isl29125_data *data = iio_priv(i2c_get_clientdata(
+ to_i2c_client(dev)));
+ return isl29125_powerdown(data);
+}
+
+static int isl29125_resume(struct device *dev)
+{
+ struct isl29125_data *data = iio_priv(i2c_get_clientdata(
+ to_i2c_client(dev)));
+ return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+ data->conf1);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(isl29125_pm_ops, isl29125_suspend, isl29125_resume);
+
+static const struct i2c_device_id isl29125_id[] = {
+ { "isl29125", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, isl29125_id);
+
+static struct i2c_driver isl29125_driver = {
+ .driver = {
+ .name = ISL29125_DRV_NAME,
+ .pm = &isl29125_pm_ops,
+ .owner = THIS_MODULE,
+ },
+ .probe = isl29125_probe,
+ .remove = isl29125_remove,
+ .id_table = isl29125_id,
+};
+module_i2c_driver(isl29125_driver);
+
+MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
+MODULE_DESCRIPTION("ISL29125 RGB light sensor driver");
+MODULE_LICENSE("GPL");