- 根目录:
- drivers
- iio
- light
- tcs3414.c
/*
* tcs3414.c - Support for TAOS TCS3414 digital color 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.
*
* Digital color sensor with 16-bit channels for red, green, blue, clear);
* 7-bit I2C slave address 0x39 (TCS3414) or 0x29, 0x49, 0x59 (TCS3413,
* TCS3415, TCS3416, resp.)
*
* TODO: sync, interrupt support, thresholds, prescaler
*/
#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 TCS3414_DRV_NAME "tcs3414"
#define TCS3414_COMMAND BIT(7)
#define TCS3414_COMMAND_WORD (TCS3414_COMMAND | BIT(5))
#define TCS3414_CONTROL (TCS3414_COMMAND | 0x00)
#define TCS3414_TIMING (TCS3414_COMMAND | 0x01)
#define TCS3414_ID (TCS3414_COMMAND | 0x04)
#define TCS3414_GAIN (TCS3414_COMMAND | 0x07)
#define TCS3414_DATA_GREEN (TCS3414_COMMAND_WORD | 0x10)
#define TCS3414_DATA_RED (TCS3414_COMMAND_WORD | 0x12)
#define TCS3414_DATA_BLUE (TCS3414_COMMAND_WORD | 0x14)
#define TCS3414_DATA_CLEAR (TCS3414_COMMAND_WORD | 0x16)
#define TCS3414_CONTROL_ADC_VALID BIT(4)
#define TCS3414_CONTROL_ADC_EN BIT(1)
#define TCS3414_CONTROL_POWER BIT(0)
#define TCS3414_INTEG_MASK GENMASK(1, 0)
#define TCS3414_INTEG_12MS 0x0
#define TCS3414_INTEG_100MS 0x1
#define TCS3414_INTEG_400MS 0x2
#define TCS3414_GAIN_MASK GENMASK(5, 4)
#define TCS3414_GAIN_SHIFT 4
struct tcs3414_data {
struct i2c_client *client;
struct mutex lock;
u8 control;
u8 gain;
u8 timing;
u16 buffer[8]; /* 4x 16-bit + 8 bytes timestamp */
};
#define TCS3414_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_SCALE) | \
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, \
}, \
}
/* scale factors: 1/gain */
static const int tcs3414_scales[][2] = {
{1, 0}, {0, 250000}, {0, 62500}, {0, 15625}
};
/* integration time in ms */
static const int tcs3414_times[] = { 12, 100, 400 };
static const struct iio_chan_spec tcs3414_channels[] = {
TCS3414_CHANNEL(GREEN, 0, TCS3414_DATA_GREEN),
TCS3414_CHANNEL(RED, 1, TCS3414_DATA_RED),
TCS3414_CHANNEL(BLUE, 2, TCS3414_DATA_BLUE),
TCS3414_CHANNEL(CLEAR, 3, TCS3414_DATA_CLEAR),
IIO_CHAN_SOFT_TIMESTAMP(4),
};
static int tcs3414_req_data(struct tcs3414_data *data)
{
int tries = 25;
int ret;
ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
data->control | TCS3414_CONTROL_ADC_EN);
if (ret < 0)
return ret;
while (tries--) {
ret = i2c_smbus_read_byte_data(data->client, TCS3414_CONTROL);
if (ret < 0)
return ret;
if (ret & TCS3414_CONTROL_ADC_VALID)
break;
msleep(20);
}
ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
data->control);
if (ret < 0)
return ret;
if (tries < 0) {
dev_err(&data->client->dev, "data not ready\n");
return -EIO;
}
return 0;
}
static int tcs3414_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct tcs3414_data *data = iio_priv(indio_dev);
int i, ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
if (iio_buffer_enabled(indio_dev))
return -EBUSY;
mutex_lock(&data->lock);
ret = tcs3414_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_SCALE:
i = (data->gain & TCS3414_GAIN_MASK) >> TCS3414_GAIN_SHIFT;
*val = tcs3414_scales[i][0];
*val2 = tcs3414_scales[i][1];
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_INT_TIME:
*val = 0;
*val2 = tcs3414_times[data->timing & TCS3414_INTEG_MASK] * 1000;
return IIO_VAL_INT_PLUS_MICRO;
}
return -EINVAL;
}
static int tcs3414_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct tcs3414_data *data = iio_priv(indio_dev);
int i;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
for (i = 0; i < ARRAY_SIZE(tcs3414_scales); i++) {
if (val == tcs3414_scales[i][0] &&
val2 == tcs3414_scales[i][1]) {
data->gain &= ~TCS3414_GAIN_MASK;
data->gain |= i << TCS3414_GAIN_SHIFT;
return i2c_smbus_write_byte_data(
data->client, TCS3414_GAIN,
data->gain);
}
}
return -EINVAL;
case IIO_CHAN_INFO_INT_TIME:
if (val != 0)
return -EINVAL;
for (i = 0; i < ARRAY_SIZE(tcs3414_times); i++) {
if (val == tcs3414_times[i] * 1000) {
data->timing &= ~TCS3414_INTEG_MASK;
data->timing |= i;
return i2c_smbus_write_byte_data(
data->client, TCS3414_TIMING,
data->timing);
}
}
return -EINVAL;
default:
return -EINVAL;
}
}
static irqreturn_t tcs3414_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
struct tcs3414_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,
TCS3414_DATA_GREEN + 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 IIO_CONST_ATTR(scale_available, "1 0.25 0.0625 0.015625");
static IIO_CONST_ATTR_INT_TIME_AVAIL("0.012 0.1 0.4");
static struct attribute *tcs3414_attributes[] = {
&iio_const_attr_scale_available.dev_attr.attr,
&iio_const_attr_integration_time_available.dev_attr.attr,
NULL
};
static const struct attribute_group tcs3414_attribute_group = {
.attrs = tcs3414_attributes,
};
static const struct iio_info tcs3414_info = {
.read_raw = tcs3414_read_raw,
.write_raw = tcs3414_write_raw,
.attrs = &tcs3414_attribute_group,
.driver_module = THIS_MODULE,
};
static int tcs3414_buffer_preenable(struct iio_dev *indio_dev)
{
struct tcs3414_data *data = iio_priv(indio_dev);
data->control |= TCS3414_CONTROL_ADC_EN;
return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
data->control);
}
static int tcs3414_buffer_predisable(struct iio_dev *indio_dev)
{
struct tcs3414_data *data = iio_priv(indio_dev);
int ret;
ret = iio_triggered_buffer_predisable(indio_dev);
if (ret < 0)
return ret;
data->control &= ~TCS3414_CONTROL_ADC_EN;
return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
data->control);
}
static const struct iio_buffer_setup_ops tcs3414_buffer_setup_ops = {
.preenable = tcs3414_buffer_preenable,
.postenable = &iio_triggered_buffer_postenable,
.predisable = tcs3414_buffer_predisable,
};
static int tcs3414_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct tcs3414_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 = &tcs3414_info;
indio_dev->name = TCS3414_DRV_NAME;
indio_dev->channels = tcs3414_channels;
indio_dev->num_channels = ARRAY_SIZE(tcs3414_channels);
indio_dev->modes = INDIO_DIRECT_MODE;
ret = i2c_smbus_read_byte_data(data->client, TCS3414_ID);
if (ret < 0)
return ret;
switch (ret & 0xf0) {
case 0x00:
dev_info(&client->dev, "TCS3404 found\n");
break;
case 0x10:
dev_info(&client->dev, "TCS3413/14/15/16 found\n");
break;
default:
return -ENODEV;
}
data->control = TCS3414_CONTROL_POWER;
ret = i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
data->control);
if (ret < 0)
return ret;
data->timing = TCS3414_INTEG_12MS; /* free running */
ret = i2c_smbus_write_byte_data(data->client, TCS3414_TIMING,
data->timing);
if (ret < 0)
return ret;
ret = i2c_smbus_read_byte_data(data->client, TCS3414_GAIN);
if (ret < 0)
return ret;
data->gain = ret;
ret = iio_triggered_buffer_setup(indio_dev, NULL,
tcs3414_trigger_handler, &tcs3414_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 tcs3414_powerdown(struct tcs3414_data *data)
{
return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
data->control & ~(TCS3414_CONTROL_POWER |
TCS3414_CONTROL_ADC_EN));
}
static int tcs3414_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);
tcs3414_powerdown(iio_priv(indio_dev));
return 0;
}
#ifdef CONFIG_PM_SLEEP
static int tcs3414_suspend(struct device *dev)
{
struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
to_i2c_client(dev)));
return tcs3414_powerdown(data);
}
static int tcs3414_resume(struct device *dev)
{
struct tcs3414_data *data = iio_priv(i2c_get_clientdata(
to_i2c_client(dev)));
return i2c_smbus_write_byte_data(data->client, TCS3414_CONTROL,
data->control);
}
#endif
static SIMPLE_DEV_PM_OPS(tcs3414_pm_ops, tcs3414_suspend, tcs3414_resume);
static const struct i2c_device_id tcs3414_id[] = {
{ "tcs3414", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, tcs3414_id);
static struct i2c_driver tcs3414_driver = {
.driver = {
.name = TCS3414_DRV_NAME,
.pm = &tcs3414_pm_ops,
.owner = THIS_MODULE,
},
.probe = tcs3414_probe,
.remove = tcs3414_remove,
.id_table = tcs3414_id,
};
module_i2c_driver(tcs3414_driver);
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("TCS3414 digital color sensors driver");
MODULE_LICENSE("GPL");