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path: root/drivers/iio/light/tcs3472.c
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Diffstat (limited to 'drivers/iio/light/tcs3472.c')
-rw-r--r--drivers/iio/light/tcs3472.c367
1 files changed, 367 insertions, 0 deletions
diff --git a/drivers/iio/light/tcs3472.c b/drivers/iio/light/tcs3472.c
new file mode 100644
index 000000000000..45df2204614a
--- /dev/null
+++ b/drivers/iio/light/tcs3472.c
@@ -0,0 +1,367 @@
+/*
+ * tcs3472.c - Support for TAOS TCS3472 color light-to-digital converter
+ *
+ * Copyright (c) 2013 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.
+ *
+ * Color light sensor with 16-bit channels for red, green, blue, clear);
+ * 7-bit I2C slave address 0x39 (TCS34721, TCS34723) or 0x29 (TCS34725,
+ * TCS34727)
+ *
+ * TODO: interrupt support, thresholds, wait time
+ */
+
+#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 TCS3472_DRV_NAME "tcs3472"
+
+#define TCS3472_COMMAND BIT(7)
+#define TCS3472_AUTO_INCR BIT(5)
+
+#define TCS3472_ENABLE (TCS3472_COMMAND | 0x00)
+#define TCS3472_ATIME (TCS3472_COMMAND | 0x01)
+#define TCS3472_WTIME (TCS3472_COMMAND | 0x03)
+#define TCS3472_AILT (TCS3472_COMMAND | 0x04)
+#define TCS3472_AIHT (TCS3472_COMMAND | 0x06)
+#define TCS3472_PERS (TCS3472_COMMAND | 0x0c)
+#define TCS3472_CONFIG (TCS3472_COMMAND | 0x0d)
+#define TCS3472_CONTROL (TCS3472_COMMAND | 0x0f)
+#define TCS3472_ID (TCS3472_COMMAND | 0x12)
+#define TCS3472_STATUS (TCS3472_COMMAND | 0x13)
+#define TCS3472_CDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x14)
+#define TCS3472_RDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x16)
+#define TCS3472_GDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x18)
+#define TCS3472_BDATA (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x1a)
+
+#define TCS3472_STATUS_AVALID BIT(0)
+#define TCS3472_ENABLE_AEN BIT(1)
+#define TCS3472_ENABLE_PON BIT(0)
+#define TCS3472_CONTROL_AGAIN_MASK (BIT(0) | BIT(1))
+
+struct tcs3472_data {
+ struct i2c_client *client;
+ u8 enable;
+ u8 control;
+ u8 atime;
+ u16 buffer[8]; /* 4 16-bit channels + 64-bit timestamp */
+};
+
+#define TCS3472_CHANNEL(_color, _si, _addr) { \
+ .type = IIO_INTENSITY, \
+ .modified = 1, \
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_CALIBSCALE) | \
+ BIT(IIO_CHAN_INFO_INT_TIME), \
+ .channel2 = IIO_MOD_LIGHT_##_color, \
+ .address = _addr, \
+ .scan_index = _si, \
+ .scan_type = IIO_ST('u', 16, 16, 0), \
+}
+
+static const int tcs3472_agains[] = { 1, 4, 16, 60 };
+
+static const struct iio_chan_spec tcs3472_channels[] = {
+ TCS3472_CHANNEL(CLEAR, 0, TCS3472_CDATA),
+ TCS3472_CHANNEL(RED, 1, TCS3472_RDATA),
+ TCS3472_CHANNEL(GREEN, 2, TCS3472_GDATA),
+ TCS3472_CHANNEL(BLUE, 3, TCS3472_BDATA),
+ IIO_CHAN_SOFT_TIMESTAMP(4),
+};
+
+static int tcs3472_req_data(struct tcs3472_data *data)
+{
+ int tries = 50;
+ int ret;
+
+ while (tries--) {
+ ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);
+ if (ret < 0)
+ return ret;
+ if (ret & TCS3472_STATUS_AVALID)
+ break;
+ msleep(20);
+ }
+
+ if (tries < 0) {
+ dev_err(&data->client->dev, "data not ready\n");
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int tcs3472_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct tcs3472_data *data = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = tcs3472_req_data(data);
+ if (ret < 0)
+ return ret;
+ ret = i2c_smbus_read_word_data(data->client, chan->address);
+ if (ret < 0)
+ return ret;
+ *val = ret;
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_CALIBSCALE:
+ *val = tcs3472_agains[data->control &
+ TCS3472_CONTROL_AGAIN_MASK];
+ return IIO_VAL_INT;
+ case IIO_CHAN_INFO_INT_TIME:
+ *val = 0;
+ *val2 = (256 - data->atime) * 2400;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ return -EINVAL;
+}
+
+static int tcs3472_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct tcs3472_data *data = iio_priv(indio_dev);
+ int i;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_CALIBSCALE:
+ if (val2 != 0)
+ return -EINVAL;
+ for (i = 0; i < ARRAY_SIZE(tcs3472_agains); i++) {
+ if (val == tcs3472_agains[i]) {
+ data->control &= ~TCS3472_CONTROL_AGAIN_MASK;
+ data->control |= i;
+ return i2c_smbus_write_byte_data(
+ data->client, TCS3472_CONTROL,
+ data->control);
+ }
+ }
+ return -EINVAL;
+ case IIO_CHAN_INFO_INT_TIME:
+ if (val != 0)
+ return -EINVAL;
+ for (i = 0; i < 256; i++) {
+ if (val2 == (256 - i) * 2400) {
+ data->atime = i;
+ return i2c_smbus_write_word_data(
+ data->client, TCS3472_ATIME,
+ data->atime);
+ }
+
+ }
+ return -EINVAL;
+ }
+ return -EINVAL;
+}
+
+static irqreturn_t tcs3472_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct tcs3472_data *data = iio_priv(indio_dev);
+ int len = 0;
+ int i, j = 0;
+
+ int ret = tcs3472_req_data(data);
+ if (ret < 0)
+ goto done;
+
+ for_each_set_bit(i, indio_dev->active_scan_mask,
+ indio_dev->masklength) {
+ ret = i2c_smbus_read_word_data(data->client,
+ TCS3472_CDATA + 2*i);
+ if (ret < 0)
+ goto done;
+
+ data->buffer[j++] = ret;
+ len += 2;
+ }
+
+ 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 ssize_t tcs3472_show_int_time_available(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ size_t len = 0;
+ int i;
+
+ for (i = 1; i <= 256; i++)
+ len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06d ",
+ 2400 * i);
+
+ /* replace trailing space by newline */
+ buf[len - 1] = '\n';
+
+ return len;
+}
+
+static IIO_CONST_ATTR(calibscale_available, "1 4 16 60");
+static IIO_DEV_ATTR_INT_TIME_AVAIL(tcs3472_show_int_time_available);
+
+static struct attribute *tcs3472_attributes[] = {
+ &iio_const_attr_calibscale_available.dev_attr.attr,
+ &iio_dev_attr_integration_time_available.dev_attr.attr,
+ NULL
+};
+
+static const struct attribute_group tcs3472_attribute_group = {
+ .attrs = tcs3472_attributes,
+};
+
+static const struct iio_info tcs3472_info = {
+ .read_raw = tcs3472_read_raw,
+ .write_raw = tcs3472_write_raw,
+ .attrs = &tcs3472_attribute_group,
+ .driver_module = THIS_MODULE,
+};
+
+static int tcs3472_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct tcs3472_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;
+
+ indio_dev->dev.parent = &client->dev;
+ indio_dev->info = &tcs3472_info;
+ indio_dev->name = TCS3472_DRV_NAME;
+ indio_dev->channels = tcs3472_channels;
+ indio_dev->num_channels = ARRAY_SIZE(tcs3472_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = i2c_smbus_read_byte_data(data->client, TCS3472_ID);
+ if (ret < 0)
+ return ret;
+
+ if (ret == 0x44)
+ dev_info(&client->dev, "TCS34721/34725 found\n");
+ else if (ret == 0x4d)
+ dev_info(&client->dev, "TCS34723/34727 found\n");
+ else
+ return -ENODEV;
+
+ ret = i2c_smbus_read_byte_data(data->client, TCS3472_CONTROL);
+ if (ret < 0)
+ return ret;
+ data->control = ret;
+
+ ret = i2c_smbus_read_byte_data(data->client, TCS3472_ATIME);
+ if (ret < 0)
+ return ret;
+ data->atime = ret;
+
+ ret = i2c_smbus_read_byte_data(data->client, TCS3472_ENABLE);
+ if (ret < 0)
+ return ret;
+
+ /* enable device */
+ data->enable = ret | TCS3472_ENABLE_PON | TCS3472_ENABLE_AEN;
+ ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
+ data->enable);
+ if (ret < 0)
+ return ret;
+
+ ret = iio_triggered_buffer_setup(indio_dev, NULL,
+ tcs3472_trigger_handler, NULL);
+ 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 tcs3472_powerdown(struct tcs3472_data *data)
+{
+ return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
+ data->enable & ~(TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON));
+}
+
+static int tcs3472_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);
+ tcs3472_powerdown(iio_priv(indio_dev));
+
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int tcs3472_suspend(struct device *dev)
+{
+ struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
+ to_i2c_client(dev)));
+ return tcs3472_powerdown(data);
+}
+
+static int tcs3472_resume(struct device *dev)
+{
+ struct tcs3472_data *data = iio_priv(i2c_get_clientdata(
+ to_i2c_client(dev)));
+ return i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
+ data->enable | (TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON));
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(tcs3472_pm_ops, tcs3472_suspend, tcs3472_resume);
+
+static const struct i2c_device_id tcs3472_id[] = {
+ { "tcs3472", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, tcs3472_id);
+
+static struct i2c_driver tcs3472_driver = {
+ .driver = {
+ .name = TCS3472_DRV_NAME,
+ .pm = &tcs3472_pm_ops,
+ .owner = THIS_MODULE,
+ },
+ .probe = tcs3472_probe,
+ .remove = tcs3472_remove,
+ .id_table = tcs3472_id,
+};
+module_i2c_driver(tcs3472_driver);
+
+MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
+MODULE_DESCRIPTION("TCS3472 color light sensors driver");
+MODULE_LICENSE("GPL");