iio: Add Intersil isl29125 digital color light sensor driver

datasheet: http://www.intersil.com/content/dam/Intersil/documents/isl2/isl29125.pdf

Signed-off-by: Peter Meerwald <pmeerw@pmeerw.net>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

3 files changed, 360 insertions, 0 deletions

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index c89740d4748f..7d83dca6d080 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -62,6 +62,18 @@ config GP2AP020A00F
           To compile this driver as a module, choose M here: the
           module will be called gp2ap020a00f.
 
+config ISL29125
+        tristate "Intersil ISL29125 digital color light sensor"
+        depends on I2C
+        select IIO_BUFFER
+        select IIO_TRIGGERED_BUFFER
+        help
+          Say Y here if you want to build a driver for the Intersil ISL29125
+          RGB light sensor for I2C.
+
+          To compile this driver as a module, choose M here: the module will be
+          called isl29125.
+
 config HID_SENSOR_ALS
         depends on HID_SENSOR_HUB
         select IIO_BUFFER
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index 3eb36e5151fa..f3d1857b2083 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_CM36651)		+= cm36651.o
 obj-$(CONFIG_GP2AP020A00F)      += gp2ap020a00f.o
 obj-$(CONFIG_HID_SENSOR_ALS)    += hid-sensor-als.o
 obj-$(CONFIG_HID_SENSOR_PROX)   += hid-sensor-prox.o
+obj-$(CONFIG_ISL29125)          += isl29125.o
 obj-$(CONFIG_SENSORS_LM3533)    += lm3533-als.o
 obj-$(CONFIG_LTR501)            += ltr501.o
 obj-$(CONFIG_SENSORS_TSL2563)   += tsl2563.o
diff --git a/drivers/iio/light/isl29125.c b/drivers/iio/light/isl29125.c
new file mode 100644
index 000000000000..c82f4a6f8464
--- /dev/null
+++ b/drivers/iio/light/isl29125.c
@@ -0,0 +1,347 @@
+/*
+ * isl29125.c - Support for Intersil ISL29125 RGB light sensor
+ *
+ * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
+ *
+ * This file is subject to the terms and conditions of version 2 of
+ * the GNU General Public License.  See the file COPYING in the main
+ * directory of this archive for more details.
+ *
+ * RGB light sensor with 16-bit channels for red, green, blue);
+ * 7-bit I2C slave address 0x44
+ *
+ * TODO: interrupt support, IR compensation, thresholds, 12bit
+ */
+
+#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 ISL29125_DRV_NAME "isl29125"
+
+#define ISL29125_DEVICE_ID 0x00
+#define ISL29125_CONF1 0x01
+#define ISL29125_CONF2 0x02
+#define ISL29125_CONF3 0x03
+#define ISL29125_STATUS 0x08
+#define ISL29125_GREEN_DATA 0x09
+#define ISL29125_RED_DATA 0x0b
+#define ISL29125_BLUE_DATA 0x0d
+
+#define ISL29125_ID 0x7d
+
+#define ISL29125_MODE_MASK GENMASK(2, 0)
+#define ISL29125_MODE_PD 0x0
+#define ISL29125_MODE_G 0x1
+#define ISL29125_MODE_R 0x2
+#define ISL29125_MODE_B 0x3
+#define ISL29125_MODE_RGB 0x5
+
+#define ISL29125_MODE_RANGE BIT(3)
+
+#define ISL29125_STATUS_CONV BIT(1)
+
+struct isl29125_data {
+        struct i2c_client *client;
+        struct mutex lock;
+        u8 conf1;
+        u16 buffer[8]; /* 3x 16-bit, padding, 8 bytes timestamp */
+};
+
+#define ISL29125_CHANNEL(_color, _si) { \
+        .type = IIO_INTENSITY, \
+        .modified = 1, \
+        .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
+        .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+        .channel2 = IIO_MOD_LIGHT_##_color, \
+        .scan_index = _si, \
+        .scan_type = { \
+                .sign = 'u', \
+                .realbits = 16, \
+                .storagebits = 16, \
+                .endianness = IIO_CPU, \
+        }, \
+}
+
+static const struct iio_chan_spec isl29125_channels[] = {
+        ISL29125_CHANNEL(GREEN, 0),
+        ISL29125_CHANNEL(RED, 1),
+        ISL29125_CHANNEL(BLUE, 2),
+        IIO_CHAN_SOFT_TIMESTAMP(3),
+};
+
+static const struct {
+        u8 mode, data;
+} isl29125_regs[] = {
+        {ISL29125_MODE_G, ISL29125_GREEN_DATA},
+        {ISL29125_MODE_R, ISL29125_RED_DATA},
+        {ISL29125_MODE_B, ISL29125_BLUE_DATA},
+};
+
+static int isl29125_read_data(struct isl29125_data *data, int si)
+{
+        int tries = 5;
+        int ret;
+
+        ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+                data->conf1 | isl29125_regs[si].mode);
+        if (ret < 0)
+                return ret;
+
+        msleep(101);
+
+        while (tries--) {
+                ret = i2c_smbus_read_byte_data(data->client, ISL29125_STATUS);
+                if (ret < 0)
+                        goto fail;
+                if (ret & ISL29125_STATUS_CONV)
+                        break;
+                msleep(20);
+        }
+
+        if (tries < 0) {
+                dev_err(&data->client->dev, "data not ready\n");
+                ret = -EIO;
+                goto fail;
+        }
+
+        ret = i2c_smbus_read_word_data(data->client, isl29125_regs[si].data);
+
+fail:
+        i2c_smbus_write_byte_data(data->client, ISL29125_CONF1, data->conf1);
+        return ret;
+}
+
+static int isl29125_read_raw(struct iio_dev *indio_dev,
+                           struct iio_chan_spec const *chan,
+                           int *val, int *val2, long mask)
+{
+        struct isl29125_data *data = iio_priv(indio_dev);
+        int ret;
+
+        switch (mask) {
+        case IIO_CHAN_INFO_RAW:
+                if (iio_buffer_enabled(indio_dev))
+                        return -EBUSY;
+                mutex_lock(&data->lock);
+                ret = isl29125_read_data(data, chan->scan_index);
+                mutex_unlock(&data->lock);
+                if (ret < 0)
+                        return ret;
+                *val = ret;
+                return IIO_VAL_INT;
+        case IIO_CHAN_INFO_SCALE:
+                *val = 0;
+                if (data->conf1 & ISL29125_MODE_RANGE)
+                        *val2 = 152590; /* 10k lux full range */
+                else
+                        *val2 = 5722; /* 375 lux full range */
+                return IIO_VAL_INT_PLUS_MICRO;
+        }
+        return -EINVAL;
+}
+
+static int isl29125_write_raw(struct iio_dev *indio_dev,
+                               struct iio_chan_spec const *chan,
+                               int val, int val2, long mask)
+{
+        struct isl29125_data *data = iio_priv(indio_dev);
+
+        switch (mask) {
+        case IIO_CHAN_INFO_SCALE:
+                if (val != 0)
+                        return -EINVAL;
+                if (val2 == 152590)
+                        data->conf1 |= ISL29125_MODE_RANGE;
+                else if (val2 == 5722)
+                        data->conf1 &= ~ISL29125_MODE_RANGE;
+                else
+                        return -EINVAL;
+                return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+                        data->conf1);
+        default:
+                return -EINVAL;
+        }
+}
+
+static irqreturn_t isl29125_trigger_handler(int irq, void *p)
+{
+        struct iio_poll_func *pf = p;
+        struct iio_dev *indio_dev = pf->indio_dev;
+        struct isl29125_data *data = iio_priv(indio_dev);
+        int i, j = 0;
+
+        for_each_set_bit(i, indio_dev->active_scan_mask,
+                indio_dev->masklength) {
+                int ret = i2c_smbus_read_word_data(data->client,
+                        isl29125_regs[i].data);
+                if (ret < 0)
+                        goto done;
+
+                data->buffer[j++] = ret;
+        }
+
+        iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+                iio_get_time_ns());
+
+done:
+        iio_trigger_notify_done(indio_dev->trig);
+
+        return IRQ_HANDLED;
+}
+
+static const struct iio_info isl29125_info = {
+        .read_raw = isl29125_read_raw,
+        .write_raw = isl29125_write_raw,
+        .driver_module = THIS_MODULE,
+};
+
+static int isl29125_buffer_preenable(struct iio_dev *indio_dev)
+{
+        struct isl29125_data *data = iio_priv(indio_dev);
+
+        data->conf1 |= ISL29125_MODE_RGB;
+        return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+                data->conf1);
+}
+
+static int isl29125_buffer_predisable(struct iio_dev *indio_dev)
+{
+        struct isl29125_data *data = iio_priv(indio_dev);
+        int ret;
+
+        ret = iio_triggered_buffer_predisable(indio_dev);
+        if (ret < 0)
+                return ret;
+
+        data->conf1 &= ~ISL29125_MODE_MASK;
+        data->conf1 |= ISL29125_MODE_PD;
+        return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+                data->conf1);
+}
+
+static const struct iio_buffer_setup_ops isl29125_buffer_setup_ops = {
+        .preenable = isl29125_buffer_preenable,
+        .postenable = &iio_triggered_buffer_postenable,
+        .predisable = isl29125_buffer_predisable,
+};
+
+static int isl29125_probe(struct i2c_client *client,
+                           const struct i2c_device_id *id)
+{
+        struct isl29125_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 = &isl29125_info;
+        indio_dev->name = ISL29125_DRV_NAME;
+        indio_dev->channels = isl29125_channels;
+        indio_dev->num_channels = ARRAY_SIZE(isl29125_channels);
+        indio_dev->modes = INDIO_DIRECT_MODE;
+
+        ret = i2c_smbus_read_byte_data(data->client, ISL29125_DEVICE_ID);
+        if (ret < 0)
+                return ret;
+        if (ret != ISL29125_ID)
+                return -ENODEV;
+
+        data->conf1 = ISL29125_MODE_PD | ISL29125_MODE_RANGE;
+        ret = i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+                data->conf1);
+        if (ret < 0)
+                return ret;
+
+        ret = i2c_smbus_write_byte_data(data->client, ISL29125_STATUS, 0);
+        if (ret < 0)
+                return ret;
+
+        ret = iio_triggered_buffer_setup(indio_dev, NULL,
+                isl29125_trigger_handler, &isl29125_buffer_setup_ops);
+        if (ret < 0)
+                return ret;
+
+        ret = iio_device_register(indio_dev);
+        if (ret < 0)
+                goto buffer_cleanup;
+
+        return 0;
+
+buffer_cleanup:
+        iio_triggered_buffer_cleanup(indio_dev);
+        return ret;
+}
+
+static int isl29125_powerdown(struct isl29125_data *data)
+{
+        return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+                (data->conf1 & ~ISL29125_MODE_MASK) | ISL29125_MODE_PD);
+}
+
+static int isl29125_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);
+        isl29125_powerdown(iio_priv(indio_dev));
+
+        return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int isl29125_suspend(struct device *dev)
+{
+        struct isl29125_data *data = iio_priv(i2c_get_clientdata(
+                to_i2c_client(dev)));
+        return isl29125_powerdown(data);
+}
+
+static int isl29125_resume(struct device *dev)
+{
+        struct isl29125_data *data = iio_priv(i2c_get_clientdata(
+                to_i2c_client(dev)));
+        return i2c_smbus_write_byte_data(data->client, ISL29125_CONF1,
+                data->conf1);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(isl29125_pm_ops, isl29125_suspend, isl29125_resume);
+
+static const struct i2c_device_id isl29125_id[] = {
+        { "isl29125", 0 },
+        { }
+};
+MODULE_DEVICE_TABLE(i2c, isl29125_id);
+
+static struct i2c_driver isl29125_driver = {
+        .driver = {
+                .name   = ISL29125_DRV_NAME,
+                .pm     = &isl29125_pm_ops,
+                .owner  = THIS_MODULE,
+        },
+        .probe          = isl29125_probe,
+        .remove         = isl29125_remove,
+        .id_table       = isl29125_id,
+};
+module_i2c_driver(isl29125_driver);
+
+MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
+MODULE_DESCRIPTION("ISL29125 RGB light sensor driver");
+MODULE_LICENSE("GPL");