Linux-libre 4.4-gnupck-4.4-gnu

1 files changed, 89 insertions, 3 deletions

diff --git a/drivers/iio/temperature/mlx90614.c b/drivers/iio/temperature/mlx90614.c
index 5d033a5af..a570c2e2a 100644
--- a/drivers/iio/temperature/mlx90614.c
+++ b/drivers/iio/temperature/mlx90614.c
@@ -3,6 +3,7 @@
  *
  * Copyright (c) 2014 Peter Meerwald <pmeerw@pmeerw.net>
  * Copyright (c) 2015 Essensium NV
+ * Copyright (c) 2015 Melexis
  *
  * 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
@@ -20,7 +21,6 @@
  * always has a pull-up so we do not need an extra GPIO to drive it high.  If
  * the "wakeup" GPIO is not given, power management will be disabled.
  *
- * TODO: filter configuration
  */
 
 #include <linux/err.h>
@@ -32,6 +32,7 @@
 #include <linux/pm_runtime.h>
 
 #include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
 
 #define MLX90614_OP_RAM		0x00
 #define MLX90614_OP_EEPROM	0x20
@@ -71,6 +72,7 @@
 #define MLX90614_CONST_SCALE 20 /* Scale in milliKelvin (0.02 * 1000) */
 #define MLX90614_CONST_RAW_EMISSIVITY_MAX 65535 /* max value for emissivity */
 #define MLX90614_CONST_EMISSIVITY_RESOLUTION 15259 /* 1/65535 ~ 0.000015259 */
+#define MLX90614_CONST_FIR 0x7 /* Fixed value for FIR part of low pass filter */
 
 struct mlx90614_data {
 	struct i2c_client *client;
@@ -79,6 +81,20 @@ struct mlx90614_data {
 	unsigned long ready_timestamp; /* in jiffies */
 };
 
+/* Bandwidth values for IIR filtering */
+static const int mlx90614_iir_values[] = {77, 31, 20, 15, 723, 153, 110, 86};
+static IIO_CONST_ATTR(in_temp_object_filter_low_pass_3db_frequency_available,
+		      "0.15 0.20 0.31 0.77 0.86 1.10 1.53 7.23");
+
+static struct attribute *mlx90614_attributes[] = {
+	&iio_const_attr_in_temp_object_filter_low_pass_3db_frequency_available.dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group mlx90614_attr_group = {
+	.attrs = mlx90614_attributes,
+};
+
 /*
  * Erase an address and write word.
  * The mutex must be locked before calling.
@@ -117,6 +133,43 @@ static s32 mlx90614_write_word(const struct i2c_client *client, u8 command,
 	return ret;
 }
 
+/*
+ * Find the IIR value inside mlx90614_iir_values array and return its position
+ * which is equivalent to the bit value in sensor register
+ */
+static inline s32 mlx90614_iir_search(const struct i2c_client *client,
+				      int value)
+{
+	int i;
+	s32 ret;
+
+	for (i = 0; i < ARRAY_SIZE(mlx90614_iir_values); ++i) {
+		if (value == mlx90614_iir_values[i])
+			break;
+	}
+
+	if (i == ARRAY_SIZE(mlx90614_iir_values))
+		return -EINVAL;
+
+	/*
+	 * CONFIG register values must not be changed so
+	 * we must read them before we actually write
+	 * changes
+	 */
+	ret = i2c_smbus_read_word_data(client, MLX90614_CONFIG);
+	if (ret < 0)
+		return ret;
+
+	ret &= ~MLX90614_CONFIG_FIR_MASK;
+	ret |= MLX90614_CONST_FIR << MLX90614_CONFIG_FIR_SHIFT;
+	ret &= ~MLX90614_CONFIG_IIR_MASK;
+	ret |= i << MLX90614_CONFIG_IIR_SHIFT;
+
+	/* Write changed values */
+	ret = mlx90614_write_word(client, MLX90614_CONFIG, ret);
+	return ret;
+}
+
 #ifdef CONFIG_PM
 /*
  * If @startup is true, make sure MLX90614_TIMING_STARTUP ms have elapsed since
@@ -236,6 +289,21 @@ static int mlx90614_read_raw(struct iio_dev *indio_dev,
 			*val2 = ret * MLX90614_CONST_EMISSIVITY_RESOLUTION;
 		}
 		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR setting with
+							     FIR = 1024 */
+		mlx90614_power_get(data, false);
+		mutex_lock(&data->lock);
+		ret = i2c_smbus_read_word_data(data->client, MLX90614_CONFIG);
+		mutex_unlock(&data->lock);
+		mlx90614_power_put(data);
+
+		if (ret < 0)
+			return ret;
+
+		*val = mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] / 100;
+		*val2 = (mlx90614_iir_values[ret & MLX90614_CONFIG_IIR_MASK] % 100) *
+			10000;
+		return IIO_VAL_INT_PLUS_MICRO;
 	default:
 		return -EINVAL;
 	}
@@ -263,6 +331,18 @@ static int mlx90614_write_raw(struct iio_dev *indio_dev,
 		mlx90614_power_put(data);
 
 		return ret;
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY: /* IIR Filter setting */
+		if (val < 0 || val2 < 0)
+			return -EINVAL;
+
+		mlx90614_power_get(data, false);
+		mutex_lock(&data->lock);
+		ret = mlx90614_iir_search(data->client,
+					  val * 100 + val2 / 10000);
+		mutex_unlock(&data->lock);
+		mlx90614_power_put(data);
+
+		return ret;
 	default:
 		return -EINVAL;
 	}
@@ -275,6 +355,8 @@ static int mlx90614_write_raw_get_fmt(struct iio_dev *indio_dev,
 	switch (mask) {
 	case IIO_CHAN_INFO_CALIBEMISSIVITY:
 		return IIO_VAL_INT_PLUS_NANO;
+	case IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY:
+		return IIO_VAL_INT_PLUS_MICRO;
 	default:
 		return -EINVAL;
 	}
@@ -294,7 +376,8 @@ static const struct iio_chan_spec mlx90614_channels[] = {
 		.modified = 1,
 		.channel2 = IIO_MOD_TEMP_OBJECT,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
-		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY),
+		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
+			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 		    BIT(IIO_CHAN_INFO_SCALE),
 	},
@@ -305,7 +388,8 @@ static const struct iio_chan_spec mlx90614_channels[] = {
 		.channel = 1,
 		.channel2 = IIO_MOD_TEMP_OBJECT,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
-		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY),
+		    BIT(IIO_CHAN_INFO_CALIBEMISSIVITY) |
+			BIT(IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY),
 		.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_OFFSET) |
 		    BIT(IIO_CHAN_INFO_SCALE),
 	},
@@ -315,6 +399,7 @@ static const struct iio_info mlx90614_info = {
 	.read_raw = mlx90614_read_raw,
 	.write_raw = mlx90614_write_raw,
 	.write_raw_get_fmt = mlx90614_write_raw_get_fmt,
+	.attrs = &mlx90614_attr_group,
 	.driver_module = THIS_MODULE,
 };
 
@@ -569,5 +654,6 @@ module_i2c_driver(mlx90614_driver);
 
 MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
 MODULE_AUTHOR("Vianney le Clément de Saint-Marcq <vianney.leclement@essensium.com>");
+MODULE_AUTHOR("Crt Mori <cmo@melexis.com>");
 MODULE_DESCRIPTION("Melexis MLX90614 contactless IR temperature sensor driver");
 MODULE_LICENSE("GPL");