CHROMIUM: light sensor: Add a calibration file to the isl29018 driver.

Backport a patch recently accepted upstream.

Defaulting to 1, this gives a way to amplify the lux value before being
reduced by the programmed adc_bit shift.
Only support whole numbers right now.  When this driver is converted to the new
IIO_CHAN framework, it will be easy to support the framework's pseudo float.

Add illuminance0_calibscale documentation to sysfs-bus-iio-light.

BUG=chrome-os-partner:1959
TEST=Confirm illuminance0_calibscale amplifies illuminance0_input values.

Signed-off-by: Bryan Freed <bfreed@chromium.org>
Change-Id: I003d0ce2fac78eadeb8e0d39ab4916105c9aabe9
Reviewed-on: http://gerrit.chromium.org/gerrit/2458
Tested-by: Bryan Freed <bfreed@chromium.org>
Reviewed-by: Benson Leung <bleung@chromium.org>

diff --git a/drivers/staging/iio/light/isl29018.c b/drivers/staging/iio/light/isl29018.c
index 38ec52b..0d4aab0 100644 (file)
--- a/drivers/staging/iio/light/isl29018.c
+++ b/drivers/staging/iio/light/isl29018.c
@@ -234,6 +234,96 @@ static int isl29018_read_proximity_ir(struct i2c_client *client, int scheme,
 }
 
 /* Sysfs interface */
+/* lux_scale */
+static ssize_t show_lux_scale(struct device *dev,
+                       struct device_attribute *attr, char *buf)
+{
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct isl29018_chip *chip = iio_priv(indio_dev);
+
+       return sprintf(buf, "%d\n", chip->lux_scale);
+}
+
+static ssize_t store_lux_scale(struct device *dev,
+               struct device_attribute *attr, const char *buf, size_t count)
+{
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct isl29018_chip *chip = iio_priv(indio_dev);
+       unsigned long lval;
+
+       lval = simple_strtoul(buf, NULL, 10);
+       if (lval == 0)
+               return -EINVAL;
+
+       mutex_lock(&chip->lock);
+       chip->lux_scale = lval;
+       mutex_unlock(&chip->lock);
+
+       return count;
+}
+
+static ssize_t get_sensor_data(struct device *dev, char *buf, int mode)
+{
+       struct iio_dev *indio_dev = dev_get_drvdata(dev);
+       struct isl29018_chip *chip = iio_priv(indio_dev);
+       struct i2c_client *client = chip->client;
+       int value = 0;
+       int status;
+
+       mutex_lock(&chip->lock);
+       switch (mode) {
+       case COMMMAND1_OPMODE_PROX_ONCE:
+               status = isl29018_read_proximity_ir(client,
+                                               chip->prox_scheme, &value);
+       break;
+
+       case COMMMAND1_OPMODE_ALS_ONCE:
+               status = isl29018_read_lux(client, &value);
+               break;
+
+       case COMMMAND1_OPMODE_IR_ONCE:
+               status = isl29018_read_ir(client, &value);
+               break;
+
+       default:
+               dev_err(&client->dev, "Mode %d is not supported\n", mode);
+               mutex_unlock(&chip->lock);
+               return -EBUSY;
+       }
+
+       if (status < 0) {
+               dev_err(&client->dev, "Error in Reading data");
+               mutex_unlock(&chip->lock);
+               return status;
+       }
+
+       mutex_unlock(&chip->lock);
+
+       return sprintf(buf, "%d\n", value);
+}
+
+
+/* Read lux */
+static ssize_t show_lux(struct device *dev,
+               struct device_attribute *devattr, char *buf)
+{
+       return get_sensor_data(dev, buf, COMMMAND1_OPMODE_ALS_ONCE);
+}
+
+/* Read ir */
+static ssize_t show_ir(struct device *dev,
+               struct device_attribute *devattr, char *buf)
+{
+       return get_sensor_data(dev, buf, COMMMAND1_OPMODE_IR_ONCE);
+}
+
+/* Read nearest ir */
+static ssize_t show_proxim_ir(struct device *dev,
+               struct device_attribute *devattr, char *buf)
+{
+       return get_sensor_data(dev, buf, COMMMAND1_OPMODE_PROX_ONCE);
+}
+
 /* range */
 static ssize_t show_range(struct device *dev,
                        struct device_attribute *attr, char *buf)
@@ -440,6 +530,11 @@ static IIO_DEVICE_ATTR(proximity_on_chip_ambient_infrared_supression,
                                        S_IRUGO | S_IWUSR,
                                        show_prox_infrared_supression,
                                        store_prox_infrared_supression, 0);
+static IIO_DEVICE_ATTR(illuminance0_input, S_IRUGO, show_lux, NULL, 0);
+static IIO_DEVICE_ATTR(illuminance0_calibscale, S_IRUGO | S_IWUSR,
+                                       show_lux_scale, store_lux_scale, 0);
+static IIO_DEVICE_ATTR(intensity_infrared_raw, S_IRUGO, show_ir, NULL, 0);
+static IIO_DEVICE_ATTR(proximity_raw, S_IRUGO, show_proxim_ir, NULL, 0);
 
 #define ISL29018_DEV_ATTR(name) (&iio_dev_attr_##name.dev_attr.attr)
 #define ISL29018_CONST_ATTR(name) (&iio_const_attr_##name.dev_attr.attr)
@@ -449,6 +544,10 @@ static struct attribute *isl29018_attributes[] = {
        ISL29018_DEV_ATTR(adc_resolution),
        ISL29018_CONST_ATTR(adc_resolution_available),
        ISL29018_DEV_ATTR(proximity_on_chip_ambient_infrared_supression),
+       ISL29018_DEV_ATTR(illuminance0_input),
+       ISL29018_DEV_ATTR(illuminance0_calibscale),
+       ISL29018_DEV_ATTR(intensity_infrared_raw),
+       ISL29018_DEV_ATTR(proximity_raw),
        NULL
 };