staging: iio: TAOS tsl258x: Device driver

Added suspend/resume functions.
Changed attribute names to match existing where applicable and updated
or documented new ABI as discussed.
Changed integration time ABI from using index (0 to 3) to use actual
gain values (1x,8x, etc.).
Removed various unused variables, declarations, and functions.
Revised code to accommodate different endianess (le16_to_cpu).
Updated error return codes in various functions.
Changed from mdelay to msleep after determining that longer wait would
be acceptable.

V5: Makefile and Kconfig cleanups by Jonathan Cameron.
Signed-off-by: Jon August Brenner <jbrenner@taosinc.com>
Acked-by: Jonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/Documentation/sysfs-bus-iio

@@ -6,6 +6,12 @@ Description:
 		Corresponds to a grouping of sensor channels. X is the IIO
 		index of the device.
 
+What:		/sys/bus/iio/devices/device[n]/power_state
+KernelVersion:	2.6.37
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This property gets/sets the device power state.
+
 What:		/sys/bus/iio/devices/triggerX
 KernelVersion:	2.6.35
 Contact:	linux-iio@vger.kernel.org

drivers/staging/iio/Documentation/sysfs-bus-iio-light

@@ -62,3 +62,16 @@ Description:
 		sensing mode. This value should be the output from a reading
 		and if expressed in SI units, should include _input. If this
 		value is not in SI units, then it should include _raw.
+
+What:		/sys/bus/iio/devices/device[n]/illuminance0_target
+KernelVersion:	2.6.37
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This property gets/sets the last known external
+		lux measurement used in/for calibration.
+
+What:		/sys/bus/iio/devices/device[n]/illuminance0_integration_time
+KernelVersion:	2.6.37
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This property gets/sets the sensors ADC analog integration time.

drivers/staging/iio/Documentation/sysfs-bus-iio-light-tsl2583

+What:		/sys/bus/iio/devices/device[n]/lux_table
+KernelVersion:	2.6.37
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This property gets/sets the table of coefficients
+		used in calculating illuminance in lux.
+
+What:		/sys/bus/iio/devices/device[n]/illuminance0_calibrate
+KernelVersion:	2.6.37
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This property causes an internal calibration of the als gain trim
+		value which is later used in calculating illuminance in lux.
+
+What:		/sys/bus/iio/devices/device[n]/illuminance0_input_target
+KernelVersion:	2.6.37
+Contact:	linux-iio@vger.kernel.org
+Description:
+		This property is the known externally illuminance (in lux).
+		It is used in the process of calibrating the device accuracy.

drivers/staging/iio/light/Kconfig

@@ -24,3 +24,9 @@ config SENSORS_ISL29018
          in lux, proximity infrared sensing and normal infrared sensing.
          Data from sensor is accessible via sysfs.
 
+config TSL2583
+	tristate "TAOS TSL2580, TSL2581, and TSL2583 light-to-digital converters"
+	depends on I2C
+	help
+	 Provides support for the TAOS tsl2580, tsl2581, and tsl2583 devices.
+	 Access ALS data via iio, sysfs.

drivers/staging/iio/light/Makefile

@@ -4,3 +4,4 @@
 
 obj-$(CONFIG_SENSORS_TSL2563)	+= tsl2563.o
 obj-$(CONFIG_SENSORS_ISL29018)	+= isl29018.o
+obj-$(CONFIG_TSL2583)	+= tsl2583.o

drivers/staging/iio/light/tsl2583.c

+/*
+ * Device driver for monitoring ambient light intensity (lux)
+ * within the TAOS tsl258x family of devices (tsl2580, tsl2581).
+ *
+ * Copyright (c) 2011, TAOS Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA	02110-1301, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/i2c.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/string.h>
+#include <linux/mutex.h>
+#include <linux/unistd.h>
+#include <linux/slab.h>
+#include "../iio.h"
+
+#define TSL258X_MAX_DEVICE_REGS		32
+
+/* Triton register offsets */
+#define	TSL258X_REG_MAX		8
+
+/* Device Registers and Masks */
+#define TSL258X_CNTRL			0x00
+#define TSL258X_ALS_TIME		0X01
+#define TSL258X_INTERRUPT		0x02
+#define TSL258X_GAIN			0x07
+#define TSL258X_REVID			0x11
+#define TSL258X_CHIPID			0x12
+#define TSL258X_ALS_CHAN0LO		0x14
+#define TSL258X_ALS_CHAN0HI		0x15
+#define TSL258X_ALS_CHAN1LO		0x16
+#define TSL258X_ALS_CHAN1HI		0x17
+#define TSL258X_TMR_LO			0x18
+#define TSL258X_TMR_HI			0x19
+
+/* tsl2583 cmd reg masks */
+#define TSL258X_CMD_REG			0x80
+#define TSL258X_CMD_SPL_FN		0x60
+#define TSL258X_CMD_ALS_INT_CLR	0X01
+
+/* tsl2583 cntrl reg masks */
+#define TSL258X_CNTL_ADC_ENBL	0x02
+#define TSL258X_CNTL_PWR_ON		0x01
+
+/* tsl2583 status reg masks */
+#define TSL258X_STA_ADC_VALID	0x01
+#define TSL258X_STA_ADC_INTR	0x10
+
+/* Lux calculation constants */
+#define	TSL258X_LUX_CALC_OVER_FLOW		65535
+
+enum {
+	TSL258X_CHIP_UNKNOWN = 0,
+	TSL258X_CHIP_WORKING = 1,
+	TSL258X_CHIP_SUSPENDED = 2
+} TSL258X_CHIP_WORKING_STATUS;
+
+/* Per-device data */
+struct taos_als_info {
+	u16 als_ch0;
+	u16 als_ch1;
+	u16 lux;
+};
+
+struct taos_settings {
+	int als_time;
+	int als_gain;
+	int als_gain_trim;
+	int als_cal_target;
+};
+
+struct tsl2583_chip {
+	struct mutex als_mutex;
+	struct i2c_client *client;
+	struct iio_dev *iio_dev;
+	struct taos_als_info als_cur_info;
+	struct taos_settings taos_settings;
+	int als_time_scale;
+	int als_saturation;
+	int taos_chip_status;
+	u8 taos_config[8];
+};
+
+/*
+ * Initial values for device - this values can/will be changed by driver.
+ * and applications as needed.
+ * These values are dynamic.
+ */
+static const u8 taos_config[8] = {
+		0x00, 0xee, 0x00, 0x03, 0x00, 0xFF, 0xFF, 0x00
+}; /*	cntrl atime intC  Athl0 Athl1 Athh0 Athh1 gain */
+
+struct taos_lux {
+	unsigned int ratio;
+	unsigned int ch0;
+	unsigned int ch1;
+};
+
+/* This structure is intentionally large to accommodate updates via sysfs. */
+/* Sized to 11 = max 10 segments + 1 termination segment */
+/* Assumption is is one and only one type of glass used  */
+struct taos_lux taos_device_lux[11] = {
+	{  9830,  8520, 15729 },
+	{ 12452, 10807, 23344 },
+	{ 14746,  6383, 11705 },
+	{ 17695,  4063,  6554 },
+};
+
+struct gainadj {
+	s16 ch0;
+	s16 ch1;
+};
+
+/* Index = (0 - 3) Used to validate the gain selection index */
+static const struct gainadj gainadj[] = {
+	{ 1, 1 },
+	{ 8, 8 },
+	{ 16, 16 },
+	{ 107, 115 }
+};
+
+/*
+ * Provides initial operational parameter defaults.
+ * These defaults may be changed through the device's sysfs files.
+ */
+static void taos_defaults(struct tsl2583_chip *chip)
+{
+	/* Operational parameters */
+	chip->taos_settings.als_time = 100;
+	/* must be a multiple of 50mS */
+	chip->taos_settings.als_gain = 0;
+	/* this is actually an index into the gain table */
+	/* assume clear glass as default */
+	chip->taos_settings.als_gain_trim = 1000;
+	/* default gain trim to account for aperture effects */
+	chip->taos_settings.als_cal_target = 130;
+	/* Known external ALS reading used for calibration */
+}
+
+/*
+ * Read a number of bytes starting at register (reg) location.
+ * Return 0, or i2c_smbus_write_byte ERROR code.
+ */
+static int
+taos_i2c_read(struct i2c_client *client, u8 reg, u8 *val, unsigned int len)
+{
+	int ret;
+	int i;
+
+	for (i = 0; i < len; i++) {
+		/* select register to write */
+		ret = i2c_smbus_write_byte(client, (TSL258X_CMD_REG | reg));
+		if (ret < 0) {
+			dev_err(&client->dev, "taos_i2c_read failed to write"
+				" register %x\n", reg);
+			return ret;
+		}
+		/* read the data */
+		*val = i2c_smbus_read_byte(client);
+		val++;
+		reg++;
+	}
+	return 0;
+}
+
+/*
+ * Reads and calculates current lux value.
+ * The raw ch0 and ch1 values of the ambient light sensed in the last
+ * integration cycle are read from the device.
+ * Time scale factor array values are adjusted based on the integration time.
+ * The raw values are multiplied by a scale factor, and device gain is obtained
+ * using gain index. Limit checks are done next, then the ratio of a multiple
+ * of ch1 value, to the ch0 value, is calculated. The array taos_device_lux[]
+ * declared above is then scanned to find the first ratio value that is just
+ * above the ratio we just calculated. The ch0 and ch1 multiplier constants in
+ * the array are then used along with the time scale factor array values, to
+ * calculate the lux.
+ */
+static int taos_get_lux(struct i2c_client *client)
+{
+	u16 ch0, ch1; /* separated ch0/ch1 data from device */
+	u32 lux; /* raw lux calculated from device data */
+	u32 ratio;
+	u8 buf[5];
+	struct taos_lux *p;
+	struct tsl2583_chip *chip = i2c_get_clientdata(client);
+	int i, ret;
+	u32 ch0lux = 0;
+	u32 ch1lux = 0;
+
+	if (mutex_trylock(&chip->als_mutex) == 0) {
+		dev_info(&client->dev, "taos_get_lux device is busy\n");
+		return chip->als_cur_info.lux; /* busy, so return LAST VALUE */
+	}
+
+	if (chip->taos_chip_status != TSL258X_CHIP_WORKING) {
+		/* device is not enabled */
+		dev_err(&client->dev, "taos_get_lux device is not enabled\n");
+		ret = -EBUSY ;
+		goto out_unlock;
+	}
+
+	ret = taos_i2c_read(client, (TSL258X_CMD_REG), &buf[0], 1);
+	if (ret < 0) {
+		dev_err(&client->dev, "taos_get_lux failed to read CMD_REG\n");
+		goto out_unlock;
+	}
+	/* is data new & valid */
+	if (!(buf[0] & TSL258X_STA_ADC_INTR)) {
+		dev_err(&client->dev, "taos_get_lux data not valid\n");
+		ret = chip->als_cur_info.lux; /* return LAST VALUE */
+		goto out_unlock;
+	}
+
+	for (i = 0; i < 4; i++) {
+		int reg = TSL258X_CMD_REG | (TSL258X_ALS_CHAN0LO + i);
+		ret = taos_i2c_read(client, reg, &buf[i], 1);
+		if (ret < 0) {
+			dev_err(&client->dev, "taos_get_lux failed to read"
+				" register %x\n", reg);
+			goto out_unlock;
+		}
+	}
+
+	/* clear status, really interrupt status (interrupts are off), but
+	 * we use the bit anyway - don't forget 0x80 - this is a command*/
+	ret = i2c_smbus_write_byte(client,
+	(TSL258X_CMD_REG | TSL258X_CMD_SPL_FN | TSL258X_CMD_ALS_INT_CLR));
+
+	if (ret < 0) {
+		dev_err(&client->dev,
+			"taos_i2c_write_command failed in taos_get_lux, err = %d\n",
+			ret);
+		goto out_unlock; /* have no data, so return failure */
+	}
+
+	/* extract ALS/lux data */
+	ch0 = le16_to_cpup((const __le16 *)&buf[0]);
+	ch1 = le16_to_cpup((const __le16 *)&buf[2]);
+
+	chip->als_cur_info.als_ch0 = ch0;
+	chip->als_cur_info.als_ch1 = ch1;
+
+	if ((ch0 >= chip->als_saturation) || (ch1 >= chip->als_saturation))
+		goto return_max;
+
+	if (ch0 == 0) {
+		/* have no data, so return LAST VALUE */
+		ret = chip->als_cur_info.lux = 0;
+		goto out_unlock;
+	}
+	/* calculate ratio */
+	ratio = (ch1 << 15) / ch0;
+	/* convert to unscaled lux using the pointer to the table */
+	for (p = (struct taos_lux *) taos_device_lux;
+	     p->ratio != 0 && p->ratio < ratio; p++)
+		;
+
+	if (p->ratio == 0) {
+		lux = 0;
+	} else {
+		ch0lux = ((ch0 * p->ch0) +
+			  (gainadj[chip->taos_settings.als_gain].ch0 >> 1))
+			 / gainadj[chip->taos_settings.als_gain].ch0;
+		ch1lux = ((ch1 * p->ch1) +
+			  (gainadj[chip->taos_settings.als_gain].ch1 >> 1))
+			 / gainadj[chip->taos_settings.als_gain].ch1;
+		lux = ch0lux - ch1lux;
+	}
+
+	/* note: lux is 31 bit max at this point */
+	if (ch1lux > ch0lux) {
+		dev_dbg(&client->dev, "No Data - Return last value\n");
+		ret = chip->als_cur_info.lux = 0;
+		goto out_unlock;
+	}
+
+	/* adjust for active time scale */
+	if (chip->als_time_scale == 0)
+		lux = 0;
+	else
+		lux = (lux + (chip->als_time_scale >> 1)) /
+			chip->als_time_scale;
+
+	/* adjust for active gain scale */
+	lux >>= 13; /* tables have factor of 8192 builtin for accuracy */
+	lux = (lux * chip->taos_settings.als_gain_trim + 500) / 1000;
+	if (lux > TSL258X_LUX_CALC_OVER_FLOW) { /* check for overflow */
+return_max:
+		lux = TSL258X_LUX_CALC_OVER_FLOW;
+	}
+
+	/* Update the structure with the latest VALID lux. */
+	chip->als_cur_info.lux = lux;
+	ret = lux;
+
+out_unlock:
+	mutex_unlock(&chip->als_mutex);
+	return ret;
+}
+
+/*
+ * Obtain single reading and calculate the als_gain_trim (later used
+ * to derive actual lux).
+ * Return updated gain_trim value.
+ */
+int taos_als_calibrate(struct i2c_client *client)
+{
+	struct tsl2583_chip *chip = i2c_get_clientdata(client);
+	u8 reg_val;
+	unsigned int gain_trim_val;
+	int ret;
+	int lux_val;
+
+	ret = i2c_smbus_write_byte(client, (TSL258X_CMD_REG | TSL258X_CNTRL));
+	if (ret < 0) {
+		dev_err(&client->dev,
+			"taos_als_calibrate failed to reach the CNTRL register, ret=%d\n",
+			ret);
+		return ret;
+	}
+
+	reg_val = i2c_smbus_read_byte(client);
+	if ((reg_val & (TSL258X_CNTL_ADC_ENBL | TSL258X_CNTL_PWR_ON))
+			!= (TSL258X_CNTL_ADC_ENBL | TSL258X_CNTL_PWR_ON)) {
+		dev_err(&client->dev,
+			"taos_als_calibrate failed: device not powered on with ADC enabled\n");
+		return -1;
+	}
+
+	ret = i2c_smbus_write_byte(client, (TSL258X_CMD_REG | TSL258X_CNTRL));
+	if (ret < 0) {
+		dev_err(&client->dev,
+			"taos_als_calibrate failed to reach the STATUS register, ret=%d\n",
+			ret);
+		return ret;
+	}
+	reg_val = i2c_smbus_read_byte(client);
+
+	if ((reg_val & TSL258X_STA_ADC_VALID) != TSL258X_STA_ADC_VALID) {
+		dev_err(&client->dev,
+			"taos_als_calibrate failed: STATUS - ADC not valid.\n");
+		return -ENODATA;
+	}
+	lux_val = taos_get_lux(client);
+	if (lux_val < 0) {
+		dev_err(&client->dev, "taos_als_calibrate failed to get lux\n");
+		return lux_val;
+	}
+	gain_trim_val = (unsigned int) (((chip->taos_settings.als_cal_target)
+			* chip->taos_settings.als_gain_trim) / lux_val);
+
+	if ((gain_trim_val < 250) || (gain_trim_val > 4000)) {
+		dev_err(&client->dev,
+			"taos_als_calibrate failed: trim_val of %d is out of range\n",
+			gain_trim_val);
+		return -ENODATA;
+	}
+	chip->taos_settings.als_gain_trim = (int) gain_trim_val;
+
+	return (int) gain_trim_val;
+}
+
+/*
+ * Turn the device on.
+ * Configuration must be set before calling this function.
+ */
+static int taos_chip_on(struct i2c_client *client)
+{
+	int i;
+	int ret = 0;
+	u8 *uP;
+	u8 utmp;
+	int als_count;
+	int als_time;
+	struct tsl2583_chip *chip = i2c_get_clientdata(client);
+
+	/* and make sure we're not already on */
+	if (chip->taos_chip_status == TSL258X_CHIP_WORKING) {
+		/* if forcing a register update - turn off, then on */
+		dev_info(&client->dev, "device is already enabled\n");
+		return   -EINVAL;
+	}
+
+	/* determine als integration regster */
+	als_count = (chip->taos_settings.als_time * 100 + 135) / 270;
+	if (als_count == 0)
+		als_count = 1; /* ensure at least one cycle */
+
+	/* convert back to time (encompasses overrides) */
+	als_time = (als_count * 27 + 5) / 10;
+	chip->taos_config[TSL258X_ALS_TIME] = 256 - als_count;
+
+	/* Set the gain based on taos_settings struct */
+	chip->taos_config[TSL258X_GAIN] = chip->taos_settings.als_gain;
+
+	/* set chip struct re scaling and saturation */
+	chip->als_saturation = als_count * 922; /* 90% of full scale */
+	chip->als_time_scale = (als_time + 25) / 50;
+
+	/* TSL258x Specific power-on / adc enable sequence
+	 * Power on the device 1st. */
+	utmp = TSL258X_CNTL_PWR_ON;
+	ret = i2c_smbus_write_byte_data(client,
+		TSL258X_CMD_REG | TSL258X_CNTRL, utmp);
+	if (ret < 0) {
+		dev_err(&client->dev, "taos_chip_on failed on CNTRL reg.\n");
+		return -1;
+	}
+
+	/* Use the following shadow copy for our delay before enabling ADC.
+	 * Write all the registers. */
+	for (i = 0, uP = chip->taos_config; i < TSL258X_REG_MAX; i++) {
+		ret = i2c_smbus_write_byte_data(client, TSL258X_CMD_REG + i,
+						*uP++);
+		if (ret < 0) {
+			dev_err(&client->dev,
+				"taos_chip_on failed on reg %d.\n", i);
+			return -1;
+		}
+	}
+
+	msleep(3);
+	/* NOW enable the ADC
+	 * initialize the desired mode of operation */
+	utmp = TSL258X_CNTL_PWR_ON | TSL258X_CNTL_ADC_ENBL;
+	ret = i2c_smbus_write_byte_data(client, TSL258X_CMD_REG | TSL258X_CNTRL,
+					utmp);
+	if (ret < 0) {
+		dev_err(&client->dev, "taos_chip_on failed on 2nd CTRL reg.\n");
+		return -1;
+	}
+	chip->taos_chip_status = TSL258X_CHIP_WORKING;
+
+	return ret;
+}
+
+static int taos_chip_off(struct i2c_client *client)
+{
+	struct tsl2583_chip *chip = i2c_get_clientdata(client);
+	int ret;
+
+	/* turn device off */
+	chip->taos_chip_status = TSL258X_CHIP_SUSPENDED;
+	ret = i2c_smbus_write_byte_data(client, TSL258X_CMD_REG | TSL258X_CNTRL,
+					0x00);
+	return ret;
+}
+
+/* Sysfs Interface Functions */
+static ssize_t taos_device_id(struct device *dev,
+struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+
+	return sprintf(buf, "%s\n", chip->client->name);
+}
+
+static ssize_t taos_power_state_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+
+	return sprintf(buf, "%d\n", chip->taos_chip_status);
+}
+
+static ssize_t taos_power_state_store(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	unsigned long value;
+
+	if (strict_strtoul(buf, 0, &value))
+		return -EINVAL;
+
+	if (value == 0)
+		taos_chip_off(chip->client);
+	else
+		taos_chip_on(chip->client);
+
+	return len;
+}
+
+static ssize_t taos_gain_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	char gain[4] = {0};
+
+	switch (chip->taos_settings.als_gain) {
+	case 0:
+		strcpy(gain, "001");
+		break;
+	case 1:
+		strcpy(gain, "008");
+		break;
+	case 2:
+		strcpy(gain, "016");
+		break;
+	case 3:
+		strcpy(gain, "111");
+		break;
+	}
+
+	return sprintf(buf, "%s\n", gain);
+}
+
+static ssize_t taos_gain_store(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	unsigned long value;
+
+	if (strict_strtoul(buf, 0, &value))
+		return -EINVAL;
+
+	switch (value) {
+	case 1:
+		chip->taos_settings.als_gain = 0;
+		break;
+	case 8:
+		chip->taos_settings.als_gain = 1;
+		break;
+	case 16:
+		chip->taos_settings.als_gain = 2;
+		break;
+	case 111:
+		chip->taos_settings.als_gain = 3;
+		break;
+	default:
+		dev_err(dev, "Invalid Gain Index (must be 1,8,16,111)\n");
+		return -1;
+	}
+
+	return len;
+}
+
+static ssize_t taos_gain_available_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%s\n", "1 8 16 111");
+}
+
+static ssize_t taos_als_time_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+
+	return sprintf(buf, "%d\n", chip->taos_settings.als_time);
+}
+
+static ssize_t taos_als_time_store(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	unsigned long value;
+
+	if (strict_strtoul(buf, 0, &value))
+		return -EINVAL;
+
+	if ((value < 50) || (value > 650))
+		return -EINVAL;
+
+	if (value % 50)
+		return -EINVAL;
+
+	 chip->taos_settings.als_time = value;
+
+	return len;
+}
+
+static ssize_t taos_als_time_available_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	return sprintf(buf, "%s\n",
+		"50 100 150 200 250 300 350 400 450 500 550 600 650");
+}
+
+static ssize_t taos_als_trim_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+
+	return sprintf(buf, "%d\n", chip->taos_settings.als_gain_trim);
+}
+
+static ssize_t taos_als_trim_store(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	unsigned long value;
+
+	if (strict_strtoul(buf, 0, &value))
+		return -EINVAL;
+
+	if (value)
+		chip->taos_settings.als_gain_trim = value;
+
+	return len;
+}
+
+static ssize_t taos_als_cal_target_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+
+	return sprintf(buf, "%d\n", chip->taos_settings.als_cal_target);
+}
+
+static ssize_t taos_als_cal_target_store(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	unsigned long value;
+
+	if (strict_strtoul(buf, 0, &value))
+		return -EINVAL;
+
+	if (value)
+		chip->taos_settings.als_cal_target = value;
+
+	return len;
+}
+
+static ssize_t taos_lux_show(struct device *dev, struct device_attribute *attr,
+	char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	int lux;
+
+	lux = taos_get_lux(chip->client);
+
+	return sprintf(buf, "%d\n", lux);
+}
+
+static ssize_t taos_do_calibrate(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	unsigned long value;
+
+	if (strict_strtoul(buf, 0, &value))
+		return -EINVAL;
+
+	if (value == 1)
+		taos_als_calibrate(chip->client);
+
+	return len;
+}
+
+static ssize_t taos_luxtable_show(struct device *dev,
+	struct device_attribute *attr, char *buf)
+{
+	int i;
+	int offset = 0;
+
+	for (i = 0; i < ARRAY_SIZE(taos_device_lux); i++) {
+		offset += sprintf(buf + offset, "%d,%d,%d,",
+				  taos_device_lux[i].ratio,
+				  taos_device_lux[i].ch0,
+				  taos_device_lux[i].ch1);
+		if (taos_device_lux[i].ratio == 0) {
+			/* We just printed the first "0" entry.
+			 * Now get rid of the extra "," and break. */
+			offset--;
+			break;
+		}
+	}
+
+	offset += sprintf(buf + offset, "\n");
+	return offset;
+}
+
+static ssize_t taos_luxtable_store(struct device *dev,
+	struct device_attribute *attr, const char *buf, size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct tsl2583_chip *chip = indio_dev->dev_data;
+	int value[ARRAY_SIZE(taos_device_lux)];
+	int n;
+
+	get_options(buf, ARRAY_SIZE(value), value);
+
+	/* We now have an array of ints starting at value[1], and
+	 * enumerated by value[0].
+	 * We expect each group of three ints is one table entry,
+	 * and the last table entry is all 0.
+	 */
+	n = value[0];
+	if ((n % 3) || n < 6 || n > ((ARRAY_SIZE(taos_device_lux) - 1) * 3)) {
+		dev_info(dev, "LUX TABLE INPUT ERROR 1 Value[0]=%d\n", n);
+		return -EINVAL;
+	}
+	if ((value[(n - 2)] | value[(n - 1)] | value[n]) != 0) {
+		dev_info(dev, "LUX TABLE INPUT ERROR 2 Value[0]=%d\n", n);
+		return -EINVAL;
+	}
+
+	if (chip->taos_chip_status == TSL258X_CHIP_WORKING)
+		taos_chip_off(chip->client);
+
+	/* Zero out the table */
+	memset(taos_device_lux, 0, sizeof(taos_device_lux));
+	memcpy(taos_device_lux, &value[1], (value[0] * 4));
+
+	taos_chip_on(chip->client);
+
+	return len;
+}
+
+static DEVICE_ATTR(name, S_IRUGO, taos_device_id, NULL);
+static DEVICE_ATTR(power_state, S_IRUGO | S_IWUSR,
+		taos_power_state_show, taos_power_state_store);
+
+static DEVICE_ATTR(illuminance0_calibscale, S_IRUGO | S_IWUSR,
+		taos_gain_show, taos_gain_store);
+static DEVICE_ATTR(illuminance0_calibscale_available, S_IRUGO,
+		taos_gain_available_show, NULL);
+
+static DEVICE_ATTR(illuminance0_integration_time, S_IRUGO | S_IWUSR,
+		taos_als_time_show, taos_als_time_store);
+static DEVICE_ATTR(illuminance0_integration_time_available, S_IRUGO,
+		taos_als_time_available_show, NULL);
+
+static DEVICE_ATTR(illuminance0_calibbias, S_IRUGO | S_IWUSR,
+		taos_als_trim_show, taos_als_trim_store);
+
+static DEVICE_ATTR(illuminance0_input_target, S_IRUGO | S_IWUSR,
+		taos_als_cal_target_show, taos_als_cal_target_store);
+
+static DEVICE_ATTR(illuminance0_input, S_IRUGO, taos_lux_show, NULL);
+static DEVICE_ATTR(illuminance0_calibrate, S_IWUSR, NULL, taos_do_calibrate);
+static DEVICE_ATTR(illuminance0_lux_table, S_IRUGO | S_IWUSR,
+		taos_luxtable_show, taos_luxtable_store);
+
+static struct attribute *sysfs_attrs_ctrl[] = {
+	&dev_attr_name.attr,
+	&dev_attr_power_state.attr,
+	&dev_attr_illuminance0_calibscale.attr,			/* Gain  */
+	&dev_attr_illuminance0_calibscale_available.attr,
+	&dev_attr_illuminance0_integration_time.attr,	/* I time*/
+	&dev_attr_illuminance0_integration_time_available.attr,
+	&dev_attr_illuminance0_calibbias.attr,			/* trim  */
+	&dev_attr_illuminance0_input_target.attr,
+	&dev_attr_illuminance0_input.attr,
+	&dev_attr_illuminance0_calibrate.attr,
+	&dev_attr_illuminance0_lux_table.attr,
+	NULL
+};
+
+static struct attribute_group tsl2583_attribute_group = {
+	.attrs = sysfs_attrs_ctrl,
+};
+
+/* Use the default register values to identify the Taos device */
+static int taos_tsl258x_device(unsigned char *bufp)
+{
+	return ((bufp[TSL258X_CHIPID] & 0xf0) == 0x90);
+}
+
+/*
+ * Client probe function - When a valid device is found, the driver's device
+ * data structure is updated, and initialization completes successfully.
+ */
+static int __devinit taos_probe(struct i2c_client *clientp,
+		      const struct i2c_device_id *idp)
+{
+	int i, ret = 0;
+	unsigned char buf[TSL258X_MAX_DEVICE_REGS];
+	static struct tsl2583_chip *chip;
+
+	if (!i2c_check_functionality(clientp->adapter,
+		I2C_FUNC_SMBUS_BYTE_DATA)) {
+		dev_err(&clientp->dev,
+			"taos_probe() - i2c smbus byte data "
+			"functions unsupported\n");
+		return -EOPNOTSUPP;
+	}
+
+	chip = kzalloc(sizeof(struct tsl2583_chip), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->client = clientp;
+	i2c_set_clientdata(clientp, chip);
+
+	mutex_init(&chip->als_mutex);
+	chip->taos_chip_status = TSL258X_CHIP_UNKNOWN;
+	memcpy(chip->taos_config, taos_config, sizeof(chip->taos_config));
+
+	for (i = 0; i < TSL258X_MAX_DEVICE_REGS; i++) {
+		ret = i2c_smbus_write_byte(clientp,
+				(TSL258X_CMD_REG | (TSL258X_CNTRL + i)));
+		if (ret < 0) {
+			dev_err(&clientp->dev, "i2c_smbus_write_bytes() to cmd "
+				"reg failed in taos_probe(), err = %d\n", ret);
+			goto fail1;
+		}
+		ret = i2c_smbus_read_byte(clientp);
+		if (ret < 0) {
+			dev_err(&clientp->dev, "i2c_smbus_read_byte from "
+				"reg failed in taos_probe(), err = %d\n", ret);
+
+			goto fail1;
+		}
+		buf[i] = ret;
+	}
+
+	if (!taos_tsl258x_device(buf)) {
+		dev_info(&clientp->dev, "i2c device found but does not match "
+			"expected id in taos_probe()\n");
+		goto fail1;
+	}
+
+	ret = i2c_smbus_write_byte(clientp, (TSL258X_CMD_REG | TSL258X_CNTRL));
+	if (ret < 0) {
+		dev_err(&clientp->dev, "i2c_smbus_write_byte() to cmd reg "
+			"failed in taos_probe(), err = %d\n", ret);
+		goto fail1;
+	}
+
+	chip->iio_dev = iio_allocate_device();
+	if (!chip->iio_dev) {
+		ret = -ENOMEM;
+		dev_err(&clientp->dev, "iio allocation failed\n");
+		goto fail1;
+	}
+
+	chip->iio_dev->attrs = &tsl2583_attribute_group;
+	chip->iio_dev->dev.parent = &clientp->dev;
+	chip->iio_dev->dev_data = (void *)(chip);
+	chip->iio_dev->driver_module = THIS_MODULE;
+	chip->iio_dev->modes = INDIO_DIRECT_MODE;
+	ret = iio_device_register(chip->iio_dev);
+	if (ret) {
+		dev_err(&clientp->dev, "iio registration failed\n");
+		goto fail1;
+	}
+
+	/* Load up the V2 defaults (these are hard coded defaults for now) */
+	taos_defaults(chip);
+
+	/* Make sure the chip is on */
+	taos_chip_on(clientp);
+
+	dev_info(&clientp->dev, "Light sensor found.\n");
+
+	return 0;
+
+fail1:
+	kfree(chip);
+
+	return ret;
+}
+
+static int taos_suspend(struct i2c_client *client, pm_message_t state)
+{
+	struct tsl2583_chip *chip = i2c_get_clientdata(client);
+	int ret = 0;
+
+	mutex_lock(&chip->als_mutex);
+
+	if (chip->taos_chip_status == TSL258X_CHIP_WORKING) {
+		ret = taos_chip_off(client);
+		chip->taos_chip_status = TSL258X_CHIP_SUSPENDED;
+	}
+
+	mutex_unlock(&chip->als_mutex);
+	return ret;
+}
+
+static int taos_resume(struct i2c_client *client)
+{
+	struct tsl2583_chip *chip = i2c_get_clientdata(client);
+	int ret = 0;
+
+	mutex_lock(&chip->als_mutex);
+
+	if (chip->taos_chip_status == TSL258X_CHIP_SUSPENDED)
+		ret = taos_chip_on(client);
+
+	mutex_unlock(&chip->als_mutex);
+	return ret;
+}
+
+
+static int __devexit taos_remove(struct i2c_client *client)
+{
+	struct tsl2583_chip *chip = i2c_get_clientdata(client);
+
+	iio_device_unregister(chip->iio_dev);
+
+	kfree(chip);
+	return 0;
+}
+
+static struct i2c_device_id taos_idtable[] = {
+	{ "tsl2580", 0 },
+	{ "tsl2581", 1 },
+	{ "tsl2583", 2 },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, taos_idtable);
+
+/* Driver definition */
+static struct i2c_driver taos_driver = {
+	.driver = {
+		.name = "tsl2583",
+	},
+	.id_table = taos_idtable,
+	.suspend	= taos_suspend,
+	.resume		= taos_resume,
+	.probe = taos_probe,
+	.remove = __devexit_p(taos_remove),
+};
+
+static int __init taos_init(void)
+{
+	return i2c_add_driver(&taos_driver);
+}
+
+static void __exit taos_exit(void)
+{
+	i2c_del_driver(&taos_driver);
+}
+
+module_init(taos_init);
+module_exit(taos_exit);
+
+MODULE_AUTHOR("J. August Brenner<jbrenner@taosinc.com>");
+MODULE_DESCRIPTION("TAOS tsl2583 ambient light sensor driver");
+MODULE_LICENSE("GPL");