Re: [PATCH 3/3] iio: Add driver for AMS/TAOS tcs3414 digital color sensor

[Jonathan Cameron <jic23@kernel.org>]

On 05/07/14 13:38, Peter Meerwald wrote:
> 16-bit digital color sensor with red, green, blue and clear channel
>
> datasheet: http://ams.com/eng/content/download/250258/975997/TCS3414_Datasheet_EN_v1.pdf
>
> Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Another nice clean driver,

Applied to the togreg branch of iio.git initially pushed out as staging.

Thanks,

> ---
>   drivers/iio/light/Kconfig   |  12 ++
>   drivers/iio/light/Makefile  |   1 +
>   drivers/iio/light/tcs3414.c | 405 ++++++++++++++++++++++++++++++++++++++++++++
>   3 files changed, 418 insertions(+)
>   create mode 100644 drivers/iio/light/tcs3414.c
>
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index 7d83dca..bf05ca5 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -128,6 +128,18 @@ config LTR501
>   	 This driver can also be built as a module.  If so, the module
>            will be called ltr501.
>
> +config TCS3414
> +	tristate "TAOS TCS3414 digital color sensor"
> +	depends on I2C
> +	select IIO_BUFFER
> +	select IIO_TRIGGERED_BUFFER
> +	help
> +	 If you say yes here you get support for the TAOS TCS3414
> +	 family of digital color sensors.
> +
> +	 This driver can also be built as a module.  If so, the module
> +	 will be called tcs3414.
> +
>   config TCS3472
>   	tristate "TAOS TCS3472 color light-to-digital converter"
>   	depends on I2C
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index f3d1857..8b8c09f 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -14,6 +14,7 @@ obj-$(CONFIG_ISL29125)		+= isl29125.o
>   obj-$(CONFIG_SENSORS_LM3533)	+= lm3533-als.o
>   obj-$(CONFIG_LTR501)		+= ltr501.o
>   obj-$(CONFIG_SENSORS_TSL2563)	+= tsl2563.o
> +obj-$(CONFIG_TCS3414)		+= tcs3414.o
>   obj-$(CONFIG_TCS3472)		+= tcs3472.o
>   obj-$(CONFIG_TSL4531)		+= tsl4531.o
>   obj-$(CONFIG_VCNL4000)		+= vcnl4000.o
> diff --git a/drivers/iio/light/tcs3414.c b/drivers/iio/light/tcs3414.c
> new file mode 100644
> index 0000000..a9e449b
> --- /dev/null
> +++ b/drivers/iio/light/tcs3414.c
> @@ -0,0 +1,405 @@
> +/*
> + * 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");
>