1 files changed, 628 insertions, 0 deletions

diff --git a/drivers/iio/light/tcs3472.c b/drivers/iio/light/tcs3472.c
new file mode 100644
index 000000000..82204414c
--- /dev/null
+++ b/drivers/iio/light/tcs3472.c
@@ -0,0 +1,628 @@
+/*
+ * 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)
+ *
+ * Datasheet: http://ams.com/eng/content/download/319364/1117183/file/TCS3472_Datasheet_EN_v2.pdf
+ *
+ * TODO: 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/events.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_SPECIAL_FUNC (BIT(5) | BIT(6))
+
+#define TCS3472_INTR_CLEAR (TCS3472_COMMAND | TCS3472_SPECIAL_FUNC | 0x06)
+
+#define TCS3472_ENABLE (TCS3472_COMMAND | 0x00)
+#define TCS3472_ATIME (TCS3472_COMMAND | 0x01)
+#define TCS3472_WTIME (TCS3472_COMMAND | 0x03)
+#define TCS3472_AILT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 0x04)
+#define TCS3472_AIHT (TCS3472_COMMAND | TCS3472_AUTO_INCR | 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_AINT BIT(4)
+#define TCS3472_STATUS_AVALID BIT(0)
+#define TCS3472_ENABLE_AIEN BIT(4)
+#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;
+	u16 low_thresh;
+	u16 high_thresh;
+	u8 enable;
+	u8 control;
+	u8 atime;
+	u8 apers;
+	/* Ensure timestamp is naturally aligned */
+	struct {
+		u16 chans[4];
+		s64 timestamp __aligned(8);
+	} scan;
+};
+
+static const struct iio_event_spec tcs3472_events[] = {
+	{
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_RISING,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE),
+	}, {
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_FALLING,
+		.mask_separate = BIT(IIO_EV_INFO_VALUE),
+	}, {
+		.type = IIO_EV_TYPE_THRESH,
+		.dir = IIO_EV_DIR_EITHER,
+		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |
+				 BIT(IIO_EV_INFO_PERIOD),
+	},
+};
+
+#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, \
+	}, \
+	.event_spec = _si ? NULL : tcs3472_events, \
+	.num_event_specs = _si ? 0 : ARRAY_SIZE(tcs3472_events), \
+}
+
+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 = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+		ret = tcs3472_req_data(data);
+		if (ret < 0) {
+			iio_device_release_direct_mode(indio_dev);
+			return ret;
+		}
+		ret = i2c_smbus_read_word_data(data->client, chan->address);
+		iio_device_release_direct_mode(indio_dev);
+		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_byte_data(
+					data->client, TCS3472_ATIME,
+					data->atime);
+			}
+
+		}
+		return -EINVAL;
+	}
+	return -EINVAL;
+}
+
+/*
+ * Translation from APERS field value to the number of consecutive out-of-range
+ * clear channel values before an interrupt is generated
+ */
+static const int tcs3472_intr_pers[] = {
+	0, 1, 2, 3, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60
+};
+
+static int tcs3472_read_event(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, enum iio_event_type type,
+	enum iio_event_direction dir, enum iio_event_info info, int *val,
+	int *val2)
+{
+	struct tcs3472_data *data = iio_priv(indio_dev);
+	int ret;
+	unsigned int period;
+
+	mutex_lock(&data->lock);
+
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		*val = (dir == IIO_EV_DIR_RISING) ?
+			data->high_thresh : data->low_thresh;
+		ret = IIO_VAL_INT;
+		break;
+	case IIO_EV_INFO_PERIOD:
+		period = (256 - data->atime) * 2400 *
+			tcs3472_intr_pers[data->apers];
+		*val = period / USEC_PER_SEC;
+		*val2 = period % USEC_PER_SEC;
+		ret = IIO_VAL_INT_PLUS_MICRO;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int tcs3472_write_event(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, enum iio_event_type type,
+	enum iio_event_direction dir, enum iio_event_info info, int val,
+	int val2)
+{
+	struct tcs3472_data *data = iio_priv(indio_dev);
+	int ret;
+	u8 command;
+	int period;
+	int i;
+
+	mutex_lock(&data->lock);
+	switch (info) {
+	case IIO_EV_INFO_VALUE:
+		switch (dir) {
+		case IIO_EV_DIR_RISING:
+			command = TCS3472_AIHT;
+			break;
+		case IIO_EV_DIR_FALLING:
+			command = TCS3472_AILT;
+			break;
+		default:
+			ret = -EINVAL;
+			goto error;
+		}
+		ret = i2c_smbus_write_word_data(data->client, command, val);
+		if (ret)
+			goto error;
+
+		if (dir == IIO_EV_DIR_RISING)
+			data->high_thresh = val;
+		else
+			data->low_thresh = val;
+		break;
+	case IIO_EV_INFO_PERIOD:
+		period = val * USEC_PER_SEC + val2;
+		for (i = 1; i < ARRAY_SIZE(tcs3472_intr_pers) - 1; i++) {
+			if (period <= (256 - data->atime) * 2400 *
+					tcs3472_intr_pers[i])
+				break;
+		}
+		ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS, i);
+		if (ret)
+			goto error;
+
+		data->apers = i;
+		break;
+	default:
+		ret = -EINVAL;
+		break;
+	}
+error:
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int tcs3472_read_event_config(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, enum iio_event_type type,
+	enum iio_event_direction dir)
+{
+	struct tcs3472_data *data = iio_priv(indio_dev);
+	int ret;
+
+	mutex_lock(&data->lock);
+	ret = !!(data->enable & TCS3472_ENABLE_AIEN);
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int tcs3472_write_event_config(struct iio_dev *indio_dev,
+	const struct iio_chan_spec *chan, enum iio_event_type type,
+	enum iio_event_direction dir, int state)
+{
+	struct tcs3472_data *data = iio_priv(indio_dev);
+	int ret = 0;
+	u8 enable_old;
+
+	mutex_lock(&data->lock);
+
+	enable_old = data->enable;
+
+	if (state)
+		data->enable |= TCS3472_ENABLE_AIEN;
+	else
+		data->enable &= ~TCS3472_ENABLE_AIEN;
+
+	if (enable_old != data->enable) {
+		ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
+						data->enable);
+		if (ret)
+			data->enable = enable_old;
+	}
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static irqreturn_t tcs3472_event_handler(int irq, void *priv)
+{
+	struct iio_dev *indio_dev = priv;
+	struct tcs3472_data *data = iio_priv(indio_dev);
+	int ret;
+
+	ret = i2c_smbus_read_byte_data(data->client, TCS3472_STATUS);
+	if (ret >= 0 && (ret & TCS3472_STATUS_AINT)) {
+		iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,
+						IIO_EV_TYPE_THRESH,
+						IIO_EV_DIR_EITHER),
+				iio_get_time_ns(indio_dev));
+
+		i2c_smbus_read_byte_data(data->client, TCS3472_INTR_CLEAR);
+	}
+
+	return IRQ_HANDLED;
+}
+
+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->scan.chans[j++] = ret;
+	}
+
+	iio_push_to_buffers_with_timestamp(indio_dev, &data->scan,
+		iio_get_time_ns(indio_dev));
+
+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,
+	.read_event_value = tcs3472_read_event,
+	.write_event_value = tcs3472_write_event,
+	.read_event_config = tcs3472_read_event_config,
+	.write_event_config = tcs3472_write_event_config,
+	.attrs = &tcs3472_attribute_group,
+};
+
+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_word_data(data->client, TCS3472_AILT);
+	if (ret < 0)
+		return ret;
+	data->low_thresh = ret;
+
+	ret = i2c_smbus_read_word_data(data->client, TCS3472_AIHT);
+	if (ret < 0)
+		return ret;
+	data->high_thresh = ret;
+
+	data->apers = 1;
+	ret = i2c_smbus_write_byte_data(data->client, TCS3472_PERS,
+					data->apers);
+	if (ret < 0)
+		return 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;
+	data->enable &= ~TCS3472_ENABLE_AIEN;
+	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;
+
+	if (client->irq) {
+		ret = request_threaded_irq(client->irq, NULL,
+					   tcs3472_event_handler,
+					   IRQF_TRIGGER_FALLING | IRQF_SHARED |
+					   IRQF_ONESHOT,
+					   client->name, indio_dev);
+		if (ret)
+			goto buffer_cleanup;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret < 0)
+		goto free_irq;
+
+	return 0;
+
+free_irq:
+	if (client->irq)
+		free_irq(client->irq, indio_dev);
+buffer_cleanup:
+	iio_triggered_buffer_cleanup(indio_dev);
+	return ret;
+}
+
+static int tcs3472_powerdown(struct tcs3472_data *data)
+{
+	int ret;
+	u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;
+
+	mutex_lock(&data->lock);
+
+	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
+		data->enable & ~enable_mask);
+	if (!ret)
+		data->enable &= ~enable_mask;
+
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+
+static int tcs3472_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+	if (client->irq)
+		free_irq(client->irq, 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)));
+	int ret;
+	u8 enable_mask = TCS3472_ENABLE_AEN | TCS3472_ENABLE_PON;
+
+	mutex_lock(&data->lock);
+
+	ret = i2c_smbus_write_byte_data(data->client, TCS3472_ENABLE,
+		data->enable | enable_mask);
+	if (!ret)
+		data->enable |= enable_mask;
+
+	mutex_unlock(&data->lock);
+
+	return ret;
+}
+#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,
+	},
+	.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");