| /* | 
 |  * 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 = { \ | 
 | 		.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: | 
 | 		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_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(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, | 
 | 	.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, | 
 | 	}, | 
 | 	.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"); |