ENGR00276684-2 hwmon: isl29023: add isl29023 driver support

ISL29023 is an integrated ambient and infrared light to digital
converter with I2C (SMBus Compatible) Interface.
(Cherry-pick from freescale internal kernel 3.0.35_4.1.0 branch)

Signed-off-by: Luwei Zhou <b45643@freescale.com>

3 files changed, 1040 insertions, 0 deletions

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index bb698e1f9e42..c807bc9f5d44 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -637,4 +637,14 @@ config INPUT_XEN_KBDDEV_FRONTEND
           To compile this driver as a module, choose M here: the
           module will be called xen-kbdfront.
 
+config INPUT_ISL29023
+        tristate "Intersil ISL29023 ambient light sensor"
+        depends on I2C && SYSFS
+        help
+          If you say yes here you get support for the Intersil ISL29023
+          ambient light sensor.
+
+          This driver can also be built as a module.  If so, the module
+          will be called isl29023.
+
 endif
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index d7fc17f11d77..d187cd5a813b 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -60,3 +60,4 @@ obj-$(CONFIG_INPUT_WISTRON_BTNS)	+= wistron_btns.o
 obj-$(CONFIG_INPUT_WM831X_ON)           += wm831x-on.o
 obj-$(CONFIG_INPUT_XEN_KBDDEV_FRONTEND) += xen-kbdfront.o
 obj-$(CONFIG_INPUT_YEALINK)             += yealink.o
+obj-$(CONFIG_INPUT_ISL29023)            += isl29023.o
diff --git a/drivers/input/misc/isl29023.c b/drivers/input/misc/isl29023.c
new file mode 100755
index 000000000000..9bcea5e3dd3f
--- /dev/null
+++ b/drivers/input/misc/isl29023.c
@@ -0,0 +1,1029 @@
+/*
+ * Copyright (C) 2011-2013 Freescale Semiconductor, Inc. All Rights Reserved.
+ */
+
+/*
+ * 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/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/mutex.h>
+#include <linux/delay.h>
+#include <linux/of.h>
+#include <linux/regulator/consumer.h>
+#include <linux/isl29023.h>
+
+#define ISL29023_DRV_NAME       "isl29023"
+#define DRIVER_VERSION          "1.0"
+
+#define ISL29023_COMMAND1               0x00
+#define ISL29023_MODE_SHIFT             (5)
+#define ISL29023_MODE_MASK              (0x7 << ISL29023_MODE_SHIFT)
+#define ISL29023_INT_FLAG_SHIFT         (2)
+#define ISL29023_INT_FLAG_MASK          (0x1 << ISL29023_INT_FLAG_SHIFT)
+#define ISL29023_INT_PERSISTS_SHIFT     (0)
+#define ISL29023_INT_PERSISTS_MASK      (0x3 << ISL29023_INT_PERSISTS_SHIFT)
+
+#define ISL29023_COMMAND2               0x01
+#define ISL29023_RES_SHIFT              (2)
+#define ISL29023_RES_MASK               (0x3 << ISL29023_RES_SHIFT)
+#define ISL29023_RANGE_SHIFT            (0)
+#define ISL29023_RANGE_MASK             (0x3 << ISL29023_RANGE_SHIFT)
+
+#define ISL29023_REG_LSB_SENSOR         0x02
+#define ISL29023_REG_MSB_SENSOR         0x03
+#define ISL29023_REG_IRQ_TH_LO_LSB      0x04
+#define ISL29023_REG_IRQ_TH_LO_MSB      0x05
+#define ISL29023_REG_IRQ_TH_HI_LSB      0x06
+#define ISL29023_REG_IRQ_TH_HI_MSB      0x07
+
+#define ISL29023_NUM_CACHABLE_REGS      8
+#define DEF_RANGE                       2
+#define DEFAULT_REGISTOR_VAL            499
+
+struct isl29023_data {
+        struct i2c_client *client;
+        struct mutex lock;
+        struct input_dev *input;
+        struct work_struct work;
+        struct workqueue_struct *workqueue;
+        char phys[32];
+        u8 reg_cache[ISL29023_NUM_CACHABLE_REGS];
+        u8 mode_before_suspend;
+        u8 mode_before_interrupt;
+        u16 rext;
+};
+
+static int gain_range[] = {
+        1000, 4000, 16000, 64000
+};
+
+/*
+ * register access helpers
+ */
+static int __isl29023_read_reg(struct i2c_client *client,
+                               u32 reg, u8 mask, u8 shift)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        return (data->reg_cache[reg] & mask) >> shift;
+}
+
+static int __isl29023_write_reg(struct i2c_client *client,
+                                u32 reg, u8 mask, u8 shift, u8 val)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        int ret = 0;
+        u8 tmp;
+
+        if (reg >= ISL29023_NUM_CACHABLE_REGS)
+                return -EINVAL;
+
+        mutex_lock(&data->lock);
+
+        tmp = data->reg_cache[reg];
+        tmp &= ~mask;
+        tmp |= val << shift;
+
+        ret = i2c_smbus_write_byte_data(client, reg, tmp);
+        if (!ret)
+                data->reg_cache[reg] = tmp;
+
+        mutex_unlock(&data->lock);
+        return ret;
+}
+
+/*
+ * internally used functions
+ */
+
+/* interrupt persists */
+static int isl29023_get_int_persists(struct i2c_client *client)
+{
+        return __isl29023_read_reg(client, ISL29023_COMMAND1,
+                ISL29023_INT_PERSISTS_MASK, ISL29023_INT_PERSISTS_SHIFT);
+}
+
+static int isl29023_set_int_persists(struct i2c_client *client,
+                                int int_persists)
+{
+        return __isl29023_write_reg(client, ISL29023_COMMAND1,
+                ISL29023_INT_PERSISTS_MASK, ISL29023_INT_PERSISTS_SHIFT,
+                int_persists);
+}
+
+/* interrupt flag */
+static int isl29023_get_int_flag(struct i2c_client *client)
+{
+        return __isl29023_read_reg(client, ISL29023_COMMAND1,
+                ISL29023_INT_FLAG_MASK, ISL29023_INT_FLAG_SHIFT);
+}
+
+static int isl29023_set_int_flag(struct i2c_client *client, int flag)
+{
+        return __isl29023_write_reg(client, ISL29023_COMMAND1,
+                ISL29023_INT_FLAG_MASK, ISL29023_INT_FLAG_SHIFT, flag);
+}
+
+/* interrupt lt */
+static int isl29023_get_int_lt(struct i2c_client *client)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        int lsb, msb, lt;
+
+        mutex_lock(&data->lock);
+        lsb = i2c_smbus_read_byte_data(client, ISL29023_REG_IRQ_TH_LO_LSB);
+
+        if (lsb < 0) {
+                mutex_unlock(&data->lock);
+                return lsb;
+        }
+
+        msb = i2c_smbus_read_byte_data(client, ISL29023_REG_IRQ_TH_LO_MSB);
+        mutex_unlock(&data->lock);
+
+        if (msb < 0)
+                return msb;
+
+        lt = ((msb << 8) | lsb);
+
+        return lt;
+}
+
+static int isl29023_set_int_lt(struct i2c_client *client, int lt)
+{
+        int ret = 0;
+        struct isl29023_data *data = i2c_get_clientdata(client);
+
+        mutex_lock(&data->lock);
+        ret = i2c_smbus_write_byte_data(client, ISL29023_REG_IRQ_TH_LO_LSB,
+                                        lt & 0xff);
+        if (ret < 0) {
+                mutex_unlock(&data->lock);
+                return ret;
+        }
+
+        ret = i2c_smbus_write_byte_data(client, ISL29023_REG_IRQ_TH_LO_MSB,
+                                        (lt >> 8) & 0xff);
+        if (ret < 0) {
+                mutex_unlock(&data->lock);
+                return ret;
+        }
+
+        data->reg_cache[ISL29023_REG_IRQ_TH_LO_MSB] = (lt >> 8) & 0xff;
+        data->reg_cache[ISL29023_REG_IRQ_TH_LO_LSB] = lt & 0xff;
+        mutex_unlock(&data->lock);
+
+        return ret;
+}
+
+/* interrupt ht */
+static int isl29023_get_int_ht(struct i2c_client *client)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        int lsb, msb, ht;
+
+        mutex_lock(&data->lock);
+        lsb = i2c_smbus_read_byte_data(client, ISL29023_REG_IRQ_TH_HI_LSB);
+
+        if (lsb < 0) {
+                mutex_unlock(&data->lock);
+                return lsb;
+        }
+
+        msb = i2c_smbus_read_byte_data(client, ISL29023_REG_IRQ_TH_HI_MSB);
+        mutex_unlock(&data->lock);
+
+        if (msb < 0)
+                return msb;
+
+        ht = ((msb << 8) | lsb);
+
+        return ht;
+}
+
+static int isl29023_set_int_ht(struct i2c_client *client, int ht)
+{
+        int ret = 0;
+        struct isl29023_data *data = i2c_get_clientdata(client);
+
+        mutex_lock(&data->lock);
+        ret = i2c_smbus_write_byte_data(client, ISL29023_REG_IRQ_TH_HI_LSB,
+                                        ht & 0xff);
+        if (ret < 0) {
+                mutex_unlock(&data->lock);
+                return ret;
+        }
+
+        ret = i2c_smbus_write_byte_data(client, ISL29023_REG_IRQ_TH_HI_MSB,
+                                        (ht >> 8) & 0xff);
+        if (ret < 0) {
+                mutex_unlock(&data->lock);
+                return ret;
+        }
+
+        data->reg_cache[ISL29023_REG_IRQ_TH_HI_MSB] = (ht >> 8) & 0xff;
+        data->reg_cache[ISL29023_REG_IRQ_TH_HI_LSB] = ht & 0xff;
+        mutex_unlock(&data->lock);
+
+        return ret;
+}
+
+/* range */
+static int isl29023_get_range(struct i2c_client *client)
+{
+        return __isl29023_read_reg(client, ISL29023_COMMAND2,
+                ISL29023_RANGE_MASK, ISL29023_RANGE_SHIFT);
+}
+
+static int isl29023_set_range(struct i2c_client *client, int range)
+{
+        return __isl29023_write_reg(client, ISL29023_COMMAND2,
+                ISL29023_RANGE_MASK, ISL29023_RANGE_SHIFT, range);
+}
+
+/* resolution */
+static int isl29023_get_resolution(struct i2c_client *client)
+{
+        return __isl29023_read_reg(client, ISL29023_COMMAND2,
+                ISL29023_RES_MASK, ISL29023_RES_SHIFT);
+}
+
+static int isl29023_set_resolution(struct i2c_client *client, int res)
+{
+        return __isl29023_write_reg(client, ISL29023_COMMAND2,
+                ISL29023_RES_MASK, ISL29023_RES_SHIFT, res);
+}
+
+/* mode */
+static int isl29023_get_mode(struct i2c_client *client)
+{
+        return __isl29023_read_reg(client, ISL29023_COMMAND1,
+                ISL29023_MODE_MASK, ISL29023_MODE_SHIFT);
+}
+
+static int isl29023_set_mode(struct i2c_client *client, int mode)
+{
+        return __isl29023_write_reg(client, ISL29023_COMMAND1,
+                ISL29023_MODE_MASK, ISL29023_MODE_SHIFT, mode);
+}
+
+/* power_state */
+static int isl29023_set_power_state(struct i2c_client *client, int state)
+{
+        return __isl29023_write_reg(client, ISL29023_COMMAND1,
+                                ISL29023_MODE_MASK, ISL29023_MODE_SHIFT,
+                                state ?
+                                ISL29023_ALS_ONCE_MODE : ISL29023_PD_MODE);
+}
+
+static int isl29023_get_power_state(struct i2c_client *client)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        u8 cmdreg = data->reg_cache[ISL29023_COMMAND1];
+
+        if (cmdreg & ISL29023_MODE_MASK)
+                return 1;
+        else
+                return 0;
+}
+
+static int isl29023_get_adc_value(struct i2c_client *client)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        int lsb, msb, range, bitdepth;
+
+        mutex_lock(&data->lock);
+        lsb = i2c_smbus_read_byte_data(client, ISL29023_REG_LSB_SENSOR);
+
+        if (lsb < 0) {
+                mutex_unlock(&data->lock);
+                return lsb;
+        }
+
+        msb = i2c_smbus_read_byte_data(client, ISL29023_REG_MSB_SENSOR);
+        mutex_unlock(&data->lock);
+
+        if (msb < 0)
+                return msb;
+
+        range = isl29023_get_range(client);
+        bitdepth = (4 - isl29023_get_resolution(client)) * 4;
+        return (((msb << 8) | lsb) * ((gain_range[range] * 499) / data->rext))
+                >> bitdepth;
+}
+
+static int isl29023_get_int_lt_value(struct i2c_client *client)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        int lsb, msb, range, bitdepth;
+
+        mutex_lock(&data->lock);
+        lsb = i2c_smbus_read_byte_data(client, ISL29023_REG_IRQ_TH_LO_LSB);
+
+        if (lsb < 0) {
+                mutex_unlock(&data->lock);
+                return lsb;
+        }
+
+        msb = i2c_smbus_read_byte_data(client, ISL29023_REG_IRQ_TH_LO_MSB);
+        mutex_unlock(&data->lock);
+
+        if (msb < 0)
+                return msb;
+
+        range = isl29023_get_range(client);
+        bitdepth = (4 - isl29023_get_resolution(client)) * 4;
+        return (((msb << 8) | lsb) * ((gain_range[range] * 499) / data->rext))
+                >> bitdepth;
+}
+
+static int isl29023_get_int_ht_value(struct i2c_client *client)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        int lsb, msb, range, bitdepth;
+
+        mutex_lock(&data->lock);
+        lsb = i2c_smbus_read_byte_data(client, ISL29023_REG_IRQ_TH_HI_LSB);
+
+        if (lsb < 0) {
+                mutex_unlock(&data->lock);
+                return lsb;
+        }
+
+        msb = i2c_smbus_read_byte_data(client, ISL29023_REG_IRQ_TH_HI_MSB);
+        mutex_unlock(&data->lock);
+
+        if (msb < 0)
+                return msb;
+
+        range = isl29023_get_range(client);
+        bitdepth = (4 - isl29023_get_resolution(client)) * 4;
+        return (((msb << 8) | lsb) * ((gain_range[range] * 499) / data->rext))
+                >> bitdepth;
+}
+
+/*
+ * sysfs layer
+ */
+
+/* interrupt persists */
+static ssize_t isl29023_show_int_persists(struct device *dev,
+                                          struct device_attribute *attr,
+                                          char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        return sprintf(buf, "%i\n", isl29023_get_int_persists(client));
+}
+
+static ssize_t isl29023_store_int_persists(struct device *dev,
+                                           struct device_attribute *attr,
+                                           const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        unsigned long val;
+        int ret;
+
+        if ((strict_strtoul(buf, 10, &val) < 0) ||
+            (val > ISL29023_INT_PERSISTS_16))
+                return -EINVAL;
+
+        ret = isl29023_set_int_persists(client, val);
+        if (ret < 0)
+                return ret;
+
+        return count;
+}
+
+static DEVICE_ATTR(int_persists, S_IWUSR | S_IRUGO,
+                   isl29023_show_int_persists, isl29023_store_int_persists);
+
+/* interrupt flag */
+static ssize_t isl29023_show_int_flag(struct device *dev,
+                                          struct device_attribute *attr,
+                                          char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        return sprintf(buf, "%i\n", isl29023_get_int_flag(client));
+}
+
+static ssize_t isl29023_store_int_flag(struct device *dev,
+                                           struct device_attribute *attr,
+                                           const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        unsigned long val;
+        int ret;
+
+        if ((strict_strtoul(buf, 10, &val) < 0) || (val > 1))
+                return -EINVAL;
+
+        ret = isl29023_set_int_flag(client, val);
+        if (ret < 0)
+                return ret;
+
+        return count;
+}
+
+static DEVICE_ATTR(int_flag, S_IWUSR | S_IRUGO,
+                   isl29023_show_int_flag, isl29023_store_int_flag);
+
+/* interrupt lt */
+static ssize_t isl29023_show_int_lt(struct device *dev,
+                                   struct device_attribute *attr, char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        return sprintf(buf, "%i\n", isl29023_get_int_lt(client));
+}
+
+static ssize_t isl29023_store_int_lt(struct device *dev,
+                                    struct device_attribute *attr,
+                                    const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        unsigned long val;
+        int ret;
+
+        if ((strict_strtoul(buf, 16, &val) < 0) || (val > 0xffff))
+                return -EINVAL;
+
+        ret = isl29023_set_int_lt(client, val);
+        if (ret < 0)
+                return ret;
+
+        return count;
+}
+
+static DEVICE_ATTR(int_lt, S_IWUSR | S_IRUGO,
+                   isl29023_show_int_lt, isl29023_store_int_lt);
+
+/* interrupt ht */
+static ssize_t isl29023_show_int_ht(struct device *dev,
+                                   struct device_attribute *attr, char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        return sprintf(buf, "%i\n", isl29023_get_int_ht(client));
+}
+
+static ssize_t isl29023_store_int_ht(struct device *dev,
+                                    struct device_attribute *attr,
+                                    const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        unsigned long val;
+        int ret;
+
+        if ((strict_strtoul(buf, 16, &val) < 0) || (val > 0xffff))
+                return -EINVAL;
+
+        ret = isl29023_set_int_ht(client, val);
+        if (ret < 0)
+                return ret;
+
+        return count;
+}
+
+static DEVICE_ATTR(int_ht, S_IWUSR | S_IRUGO,
+                   isl29023_show_int_ht, isl29023_store_int_ht);
+
+/* range */
+static ssize_t isl29023_show_range(struct device *dev,
+                                   struct device_attribute *attr, char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        return sprintf(buf, "%i\n", isl29023_get_range(client));
+}
+
+static ssize_t isl29023_store_range(struct device *dev,
+                                    struct device_attribute *attr,
+                                    const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        unsigned long val;
+        int ret;
+
+        if ((strict_strtoul(buf, 10, &val) < 0) || (val > ISL29023_RANGE_64K))
+                return -EINVAL;
+
+        ret = isl29023_set_range(client, val);
+        if (ret < 0)
+                return ret;
+
+        return count;
+}
+
+static DEVICE_ATTR(range, S_IWUSR | S_IRUGO,
+                   isl29023_show_range, isl29023_store_range);
+
+
+/* resolution */
+static ssize_t isl29023_show_resolution(struct device *dev,
+                                        struct device_attribute *attr,
+                                        char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        return sprintf(buf, "%d\n", isl29023_get_resolution(client));
+}
+
+static ssize_t isl29023_store_resolution(struct device *dev,
+                                         struct device_attribute *attr,
+                                         const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        unsigned long val;
+        int ret;
+
+        if ((strict_strtoul(buf, 10, &val) < 0) || (val > ISL29023_RES_4))
+                return -EINVAL;
+
+        ret = isl29023_set_resolution(client, val);
+        if (ret < 0)
+                return ret;
+
+        return count;
+}
+
+static DEVICE_ATTR(resolution, S_IWUSR | S_IRUGO,
+                   isl29023_show_resolution, isl29023_store_resolution);
+
+/* mode */
+static ssize_t isl29023_show_mode(struct device *dev,
+                                  struct device_attribute *attr, char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        return sprintf(buf, "%d\n", isl29023_get_mode(client));
+}
+
+static ssize_t isl29023_store_mode(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        unsigned long val;
+        int ret;
+
+        if ((strict_strtoul(buf, 10, &val) < 0) ||
+            (val > ISL29023_IR_CONT_MODE))
+                return -EINVAL;
+
+        ret = isl29023_set_mode(client, val);
+        if (ret < 0)
+                return ret;
+
+        return count;
+}
+
+static DEVICE_ATTR(mode, S_IWUSR | S_IRUGO,
+                   isl29023_show_mode, isl29023_store_mode);
+
+
+/* power state */
+static ssize_t isl29023_show_power_state(struct device *dev,
+                                         struct device_attribute *attr,
+                                         char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        return sprintf(buf, "%d\n", isl29023_get_power_state(client));
+}
+
+static ssize_t isl29023_store_power_state(struct device *dev,
+                                          struct device_attribute *attr,
+                                          const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        unsigned long val;
+        int ret;
+
+        if ((strict_strtoul(buf, 10, &val) < 0) || (val > 1))
+                return -EINVAL;
+
+        ret = isl29023_set_power_state(client, val);
+        return ret ? ret : count;
+}
+
+static DEVICE_ATTR(power_state, S_IWUSR | S_IRUGO,
+                   isl29023_show_power_state, isl29023_store_power_state);
+
+/* lux */
+static ssize_t isl29023_show_lux(struct device *dev,
+                                 struct device_attribute *attr, char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+
+        /* No LUX data if not operational */
+        if (!isl29023_get_power_state(client))
+                return -EBUSY;
+
+        return sprintf(buf, "%d\n", isl29023_get_adc_value(client));
+}
+
+static DEVICE_ATTR(lux, S_IRUGO, isl29023_show_lux, NULL);
+
+/* lux interrupt low threshold */
+static ssize_t isl29023_show_int_lt_lux(struct device *dev,
+                                 struct device_attribute *attr, char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+
+        /* No LUX data if not operational */
+        if (isl29023_get_mode(client) != ISL29023_ALS_ONCE_MODE &&
+            isl29023_get_mode(client) != ISL29023_ALS_CONT_MODE)
+                return -EIO;
+
+        return sprintf(buf, "%d\n", isl29023_get_int_lt_value(client));
+}
+
+static ssize_t isl29023_store_int_lt_lux(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        unsigned long val, lux_data;
+        int range, bitdepth, ret;
+        u8 lsb, msb;
+
+        if ((strict_strtoul(buf, 10, &val) < 0))
+                return -EINVAL;
+
+        /* No LUX data if not operational */
+        if (isl29023_get_mode(client) != ISL29023_ALS_ONCE_MODE &&
+            isl29023_get_mode(client) != ISL29023_ALS_CONT_MODE)
+                return -EIO;
+
+        if (val > (gain_range[isl29023_get_range(client)]*499/data->rext))
+                return -EINVAL;
+
+        range = isl29023_get_range(client);
+        bitdepth = (4 - isl29023_get_resolution(client)) * 4;
+        lux_data = ((unsigned long)(val << bitdepth)) /
+                ((gain_range[range] * 499) / data->rext);
+        lux_data &= 0xffff;
+
+        msb = lux_data >> 8;
+        lsb = lux_data & 0xff;
+
+        mutex_lock(&data->lock);
+        ret = i2c_smbus_write_byte_data(client, ISL29023_REG_IRQ_TH_LO_LSB,
+                                        lsb);
+        if (ret < 0) {
+                mutex_unlock(&data->lock);
+                return ret;
+        }
+
+        ret = i2c_smbus_write_byte_data(client, ISL29023_REG_IRQ_TH_LO_MSB,
+                                        msb);
+        if (ret < 0) {
+                mutex_unlock(&data->lock);
+                return ret;
+        }
+
+        data->reg_cache[ISL29023_REG_IRQ_TH_LO_MSB] = msb;
+        data->reg_cache[ISL29023_REG_IRQ_TH_LO_LSB] = lsb;
+        mutex_unlock(&data->lock);
+
+        return count;
+}
+
+static DEVICE_ATTR(int_lt_lux, S_IWUSR | S_IRUGO,
+                isl29023_show_int_lt_lux, isl29023_store_int_lt_lux);
+
+/* lux interrupt high threshold */
+static ssize_t isl29023_show_int_ht_lux(struct device *dev,
+                                 struct device_attribute *attr, char *buf)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+
+        /* No LUX data if not operational */
+        if (isl29023_get_mode(client) != ISL29023_ALS_ONCE_MODE &&
+            isl29023_get_mode(client) != ISL29023_ALS_CONT_MODE)
+                return -EIO;
+
+        return sprintf(buf, "%d\n", isl29023_get_int_ht_value(client));
+}
+
+static ssize_t isl29023_store_int_ht_lux(struct device *dev,
+                struct device_attribute *attr, const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        unsigned long val, lux_data;
+        int range, bitdepth, ret;
+        u8 lsb, msb;
+
+        if ((strict_strtoul(buf, 10, &val) < 0))
+                return -EINVAL;
+
+        /* No LUX data if not operational */
+        if (isl29023_get_mode(client) != ISL29023_ALS_ONCE_MODE &&
+            isl29023_get_mode(client) != ISL29023_ALS_CONT_MODE)
+                return -EIO;
+
+        if (val > (gain_range[isl29023_get_range(client)]*499/data->rext))
+                return -EINVAL;
+
+        range = isl29023_get_range(client);
+        bitdepth = (4 - isl29023_get_resolution(client)) * 4;
+        lux_data = ((unsigned long)(val << bitdepth)) /
+                ((gain_range[range] * 499) / data->rext);
+        lux_data &= 0xffff;
+
+        msb = lux_data >> 8;
+        lsb = lux_data & 0xff;
+
+        mutex_lock(&data->lock);
+        ret = i2c_smbus_write_byte_data(client, ISL29023_REG_IRQ_TH_HI_LSB,
+                                        lsb);
+        if (ret < 0) {
+                mutex_unlock(&data->lock);
+                return ret;
+        }
+
+        ret = i2c_smbus_write_byte_data(client, ISL29023_REG_IRQ_TH_HI_MSB,
+                                        msb);
+        if (ret < 0) {
+                mutex_unlock(&data->lock);
+                return ret;
+        }
+
+        data->reg_cache[ISL29023_REG_IRQ_TH_HI_MSB] = msb;
+        data->reg_cache[ISL29023_REG_IRQ_TH_HI_LSB] = lsb;
+        mutex_unlock(&data->lock);
+
+        return count;
+}
+
+static DEVICE_ATTR(int_ht_lux, S_IWUSR | S_IRUGO,
+                isl29023_show_int_ht_lux, isl29023_store_int_ht_lux);
+
+static struct attribute *isl29023_attributes[] = {
+        &dev_attr_int_persists.attr,
+        &dev_attr_range.attr,
+        &dev_attr_resolution.attr,
+        &dev_attr_mode.attr,
+        &dev_attr_power_state.attr,
+        &dev_attr_lux.attr,
+        &dev_attr_int_lt_lux.attr,
+        &dev_attr_int_ht_lux.attr,
+        &dev_attr_int_lt.attr,
+        &dev_attr_int_ht.attr,
+        &dev_attr_int_flag.attr,
+        NULL
+};
+
+static const struct attribute_group isl29023_attr_group = {
+        .attrs = isl29023_attributes,
+};
+
+static int isl29023_init_client(struct i2c_client *client)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+        int i;
+
+        /* read all the registers once to fill the cache.
+         * if one of the reads fails, we consider the init failed */
+        for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++) {
+                int v = i2c_smbus_read_byte_data(client, i);
+                if (v < 0)
+                        return -ENODEV;
+
+                data->reg_cache[i] = v;
+        }
+
+        /* set defaults */
+        isl29023_set_int_persists(client, ISL29023_INT_PERSISTS_8);
+        isl29023_set_int_ht(client, 0xffff);
+        isl29023_set_int_lt(client, 0x0);
+        isl29023_set_range(client, ISL29023_RANGE_16K);
+        isl29023_set_resolution(client, ISL29023_RES_16);
+        isl29023_set_mode(client, ISL29023_ALS_ONCE_MODE);
+        isl29023_set_int_flag(client, 0);
+        isl29023_set_power_state(client, 0);
+
+        return 0;
+}
+
+static void isl29023_work(struct work_struct *work)
+{
+        struct isl29023_data *data =
+                        container_of(work, struct isl29023_data, work);
+        struct i2c_client *client = data->client;
+        int lux;
+
+        /* Clear interrupt flag */
+        isl29023_set_int_flag(client, 0);
+
+        data->mode_before_interrupt = isl29023_get_mode(client);
+        lux = isl29023_get_adc_value(client);
+
+        /* To clear the interrpt status */
+        isl29023_set_power_state(client, ISL29023_PD_MODE);
+        isl29023_set_mode(client, data->mode_before_interrupt);
+
+        msleep(100);
+
+        input_report_abs(data->input, ABS_MISC, lux);
+        input_sync(data->input);
+}
+
+static irqreturn_t isl29023_irq_handler(int irq, void *handle)
+{
+        struct isl29023_data *data = handle;
+        queue_work(data->workqueue, &data->work);
+        return IRQ_HANDLED;
+}
+
+/*
+ * I2C layer
+ */
+
+static int isl29023_probe(struct i2c_client *client,
+                                    const struct i2c_device_id *id)
+{
+        struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
+        struct isl29023_data *data;
+        struct input_dev *input_dev;
+        int err = 0;
+        struct regulator *vdd = NULL;
+        u32 rext = 0;
+        struct device_node *of_node = client->dev.of_node;
+
+        vdd = devm_regulator_get(&client->dev, "vdd");
+        if (!IS_ERR(vdd)) {
+                err  = regulator_enable(vdd);
+                if (err) {
+                        dev_err(&client->dev, "vdd set voltage error\n");
+                        return err;
+                }
+        }
+
+        err = of_property_read_u32(of_node, "rext", &rext);
+        if (err)
+                rext = DEFAULT_REGISTOR_VAL;
+
+        if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE))
+                return -EIO;
+
+        data = kzalloc(sizeof(struct isl29023_data), GFP_KERNEL);
+        if (!data)
+                return -ENOMEM;
+
+        data->client = client;
+        data->rext = (u16)rext;
+        snprintf(data->phys, sizeof(data->phys),
+                 "%s", dev_name(&client->dev));
+        i2c_set_clientdata(client, data);
+        mutex_init(&data->lock);
+
+        /* initialize the ISL29023 chip */
+        err = isl29023_init_client(client);
+        if (err)
+                goto exit_kfree;
+
+        /* register sysfs hooks */
+        err = sysfs_create_group(&client->dev.kobj, &isl29023_attr_group);
+        if (err)
+                goto exit_kfree;
+
+        input_dev = input_allocate_device();
+        if (!input_dev) {
+                err = -ENOMEM;
+                goto exit_kfree;
+        }
+
+        data->input = input_dev;
+        input_dev->name = "isl29023 light sensor";
+        input_dev->id.bustype = BUS_I2C;
+        input_dev->phys = data->phys;
+
+        __set_bit(EV_ABS, input_dev->evbit);
+        input_set_abs_params(input_dev, ABS_MISC, 0,
+                        gain_range[DEF_RANGE]*499/data->rext, 0, 0);
+
+        err = input_register_device(input_dev);
+        if (err)
+                goto exit_free_input;
+
+        /* set irq type to edge falling */
+        irq_set_irq_type(client->irq, IRQF_TRIGGER_FALLING);
+        err = request_irq(client->irq, isl29023_irq_handler, 0,
+                          client->dev.driver->name, data);
+        if (err < 0) {
+                dev_err(&client->dev, "failed to register irq %d!\n",
+                        client->irq);
+                goto exit_free_input;
+        }
+
+        data->workqueue = create_singlethread_workqueue("isl29023");
+        INIT_WORK(&data->work, isl29023_work);
+        if (data->workqueue == NULL) {
+                dev_err(&client->dev, "couldn't create workqueue\n");
+                err = -ENOMEM;
+                goto exit_free_interrupt;
+        }
+
+        dev_info(&client->dev, "driver version %s enabled\n", DRIVER_VERSION);
+        return 0;
+
+exit_free_interrupt:
+        free_irq(client->irq, data);
+exit_free_input:
+        input_free_device(input_dev);
+exit_kfree:
+        kfree(data);
+        return err;
+}
+
+static int isl29023_remove(struct i2c_client *client)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+
+        cancel_work_sync(&data->work);
+        destroy_workqueue(data->workqueue);
+        free_irq(client->irq, data);
+        input_unregister_device(data->input);
+        input_free_device(data->input);
+        sysfs_remove_group(&client->dev.kobj, &isl29023_attr_group);
+        isl29023_set_power_state(client, 0);
+        kfree(i2c_get_clientdata(client));
+
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int isl29023_suspend(struct i2c_client *client, pm_message_t mesg)
+{
+        struct isl29023_data *data = i2c_get_clientdata(client);
+
+        data->mode_before_suspend = isl29023_get_mode(client);
+        return isl29023_set_power_state(client, ISL29023_PD_MODE);
+}
+
+static int isl29023_resume(struct i2c_client *client)
+{
+        int i;
+        struct isl29023_data *data = i2c_get_clientdata(client);
+
+        /* restore registers from cache */
+        for (i = 0; i < ARRAY_SIZE(data->reg_cache); i++)
+                if (i2c_smbus_write_byte_data(client, i, data->reg_cache[i]))
+                        return -EIO;
+
+        return isl29023_set_mode(client, data->mode_before_suspend);
+}
+
+#else
+#define isl29023_suspend        NULL
+#define isl29023_resume         NULL
+#endif /* CONFIG_PM */
+
+static const struct i2c_device_id isl29023_id[] = {
+        { ISL29023_DRV_NAME, 0 },
+        {}
+};
+MODULE_DEVICE_TABLE(i2c, isl29023_id);
+
+static struct i2c_driver isl29023_driver = {
+        .driver = {
+                .name   = ISL29023_DRV_NAME,
+                .owner  = THIS_MODULE,
+        },
+        .suspend = isl29023_suspend,
+        .resume = isl29023_resume,
+        .probe  = isl29023_probe,
+        .remove = isl29023_remove,
+        .id_table = isl29023_id,
+};
+
+static int __init isl29023_init(void)
+{
+        return i2c_add_driver(&isl29023_driver);
+}
+
+static void __exit isl29023_exit(void)
+{
+        i2c_del_driver(&isl29023_driver);
+}
+
+MODULE_AUTHOR("Freescale Semiconductor, Inc.");
+MODULE_DESCRIPTION("ISL29023 ambient light sensor driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRIVER_VERSION);
+
+module_init(isl29023_init);
+module_exit(isl29023_exit);