diff options
Diffstat (limited to 'drivers/iio/light/tcs3472.c')
| -rw-r--r-- | drivers/iio/light/tcs3472.c | 379 |
1 files changed, 379 insertions, 0 deletions
diff --git a/drivers/iio/light/tcs3472.c b/drivers/iio/light/tcs3472.c new file mode 100644 index 000000000..752569985 --- /dev/null +++ b/drivers/iio/light/tcs3472.c @@ -0,0 +1,379 @@ +/* + * 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; + struct mutex lock; + 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 = { \ + .sign = 'u', \ + .realbits = 16, \ + .storagebits = 16, \ + .endianness = IIO_CPU, \ + }, \ +} + +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: + if (iio_buffer_enabled(indio_dev)) + return -EBUSY; + + mutex_lock(&data->lock); + ret = tcs3472_req_data(data); + if (ret < 0) { + mutex_unlock(&data->lock); + return ret; + } + ret = i2c_smbus_read_word_data(data->client, chan->address); + mutex_unlock(&data->lock); + 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 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; + } + + 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; + mutex_init(&data->lock); + + 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"); |