IIO: Support oversampling_ratio configuration in IIO node

Signed-off-by: Gu Chaojie <[email protected]>

src/lib/io/include/sol-iio.h

@@ -20,6 +20,7 @@
 
 #include <sol-buffer.h>
 #include <sol-common-buildopts.h>
+#include <sol-str-table.h>
 
 #include <linux/limits.h>
 
@@ -80,6 +81,8 @@ typedef struct sol_iio_config {
     int buffer_size; /**< The size of reading buffer. 0: use device default; -1: disable buffer and readings will be performed on channel files on sysfs. */
     int sampling_frequency; /**< Device sampling frequency. -1 uses device default */
     char sampling_frequency_name[NAME_MAX]; /**< Sampling frequency sysfs node name. Some drivers expose the sampling frequency that is shared by channel type. Such as in_magn_sampling_frequency, in_accel_sampling_frequency. */
+    struct sol_str_table *oversampling_ratio_table; /**< Hardware applied number of measurements for acquiring one data point. The HW will do [_name]_oversampling_ratio measurements and return the average value as output data. */
+
 } sol_iio_config;
 
 /**

src/lib/io/sol-iio.c

@@ -135,6 +135,8 @@ static struct sol_vector iio_opened_devices = SOL_VECTOR_INIT(struct iio_opened_
 #define SAMPLING_FREQUENCY_DEVICE_PATH SYSFS_DEVICES_PATH "/iio:device%d/sampling_frequency"
 #define CHANNEL_SAMPLING_FREQUENCY_DEVICE_PATH SYSFS_DEVICES_PATH "/iio:device%d/%ssampling_frequency"
 
+#define CHANNEL_OVERSAMPLING_RATIO_DEVICE_PATH SYSFS_DEVICES_PATH "/iio:device%d/%soversampling_ratio"
+
 #define SAMPLING_FREQUENCY_BUFFER_PATH SYSFS_DEVICES_PATH "/iio:device%d/buffer/sampling_frequency"
 #define SAMPLING_FREQUENCY_TRIGGER_PATH SYSFS_DEVICES_PATH "/trigger%d/sampling_frequency"
 
@@ -653,6 +655,28 @@ channel_get_pure_name(const char *name)
     return NULL;
 }
 
+static bool
+iio_set_oversampling_ratio(struct sol_iio_device *device, const struct sol_iio_config *config)
+{
+    char path[PATH_MAX];
+    struct sol_str_table *iter;
+
+    SOL_NULL_CHECK(device, false);
+
+    for (iter = config->oversampling_ratio_table; iter->key; iter++) {
+        if (!iter->val)
+            continue;
+
+        if (craft_filename_path(path, sizeof(path), CHANNEL_OVERSAMPLING_RATIO_DEVICE_PATH,
+            device->device_id, iter->key)) {
+            if (sol_util_write_file(path, "%d", iter->val) > 0)
+                return true;
+        }
+    }
+
+    return false;
+}
+
 static bool
 iio_set_sampling_frequency(struct sol_iio_device *device, const struct sol_iio_config *config)
 {
@@ -949,6 +973,11 @@ sol_iio_open(int device_id, const struct sol_iio_config *config)
             SOL_WRN("Could not set device%d sampling frequency", device->device_id);
     }
 
+    if (config->oversampling_ratio_table) {
+        if (!iio_set_oversampling_ratio(device, config))
+            SOL_WRN("Could not set device%d oversampling ratio", device->device_id);
+    }
+
     device->mount_matrix = calloc(MOUNT_MATRIX_LEN, sizeof(double));
     SOL_NULL_CHECK_GOTO(device->mount_matrix, error);
 

src/modules/flow/iio/iio.json

@@ -217,6 +217,12 @@
              "description": "Offset to be added to device raw readings",
              "name": "offset"
          },
+         {
+             "data_type": "direction-vector",
+             "default": {},
+             "description": "Oversampling ratio measurement of the sensor",
+             "name": "oversampling_ratio"
+         },
          {
              "data_type": "int",
              "default": -1,
@@ -344,6 +350,12 @@
              "description": "Offset to be added to device raw readings",
              "name": "offset"
          },
+         {
+             "data_type": "int",
+             "default": 0,
+             "description": "Oversampling ratio measurement of the sensor",
+             "name": "oversampling_ratio"
+         },
          {
              "data_type": "int",
              "default": -1,
@@ -471,6 +483,12 @@
              "description": "Offset to be added to device raw readings",
              "name": "offset"
          },
+         {
+             "data_type": "int",
+             "default": 0,
+             "description": "Oversampling ratio measurement of the sensor",
+             "name": "oversampling_ratio"
+         },
          {
              "data_type": "int",
              "default": -1,

src/modules/flow/iio/nodes.c

@@ -482,6 +482,7 @@ magnet_open(struct sol_flow_node *node, void *data, const struct sol_flow_node_o
     int device_id, ret;
     struct iio_node_type *type;
 
+
     type = (struct iio_node_type *)sol_flow_node_get_type(node);
 
     SOL_FLOW_NODE_OPTIONS_SUB_API_CHECK(options, SOL_FLOW_NODE_TYPE_IIO_MAGNETOMETER_OPTIONS_API_VERSION,
@@ -505,6 +506,18 @@ magnet_open(struct sol_flow_node *node, void *data, const struct sol_flow_node_o
     SOL_INT_CHECK_GOTO(ret, >= (int)sizeof(mdata->iio_base.config.sampling_frequency_name), err);
     SOL_INT_CHECK_GOTO(ret, < 0, err);
 
+    struct sol_str_table table[] = {
+        SOL_STR_TABLE_ITEM("in_magn_x_",
+            (int16_t)opts->oversampling_ratio.x),
+        SOL_STR_TABLE_ITEM("in_magn_y_",
+            (int16_t)opts->oversampling_ratio.y),
+        SOL_STR_TABLE_ITEM("in_magn_z_",
+            (int16_t)opts->oversampling_ratio.z),
+        { }
+    };
+
+    mdata->iio_base.config.oversampling_ratio_table = table;
+
     if (mdata->iio_base.buffer_enabled) {
         mdata->iio_base.config.sol_iio_reader_cb = type->reader_cb;
         mdata->iio_base.config.data = node;
@@ -558,7 +571,7 @@ temperature_open(struct sol_flow_node *node, void *data, const struct sol_flow_n
 {
     struct iio_double_data *mdata = data;
     const struct sol_flow_node_type_iio_thermometer_options *opts;
-    int device_id;
+    int device_id, ret;
     struct iio_node_type *type;
 
     type = (struct iio_node_type *)sol_flow_node_get_type(node);
@@ -579,6 +592,19 @@ temperature_open(struct sol_flow_node *node, void *data, const struct sol_flow_n
     mdata->iio_base.data_type = DOUBLE;
     mdata->iio_base.config.buffer_size = opts->buffer_size;
     mdata->iio_base.config.sampling_frequency = opts->sampling_frequency;
+    ret = snprintf(mdata->iio_base.config.sampling_frequency_name,
+        sizeof(mdata->iio_base.config.sampling_frequency_name), "%s", "in_temp_");
+    SOL_INT_CHECK_GOTO(ret, >= (int)sizeof(mdata->iio_base.config.sampling_frequency_name), err);
+    SOL_INT_CHECK_GOTO(ret, < 0, err);
+
+    struct sol_str_table table[] = {
+        SOL_STR_TABLE_ITEM("in_temp_",
+            opts->oversampling_ratio),
+        { }
+    };
+
+    mdata->iio_base.config.oversampling_ratio_table = table;
+
     if (mdata->iio_base.buffer_enabled) {
         mdata->iio_base.config.sol_iio_reader_cb = type->reader_cb;
         mdata->iio_base.config.data = node;
@@ -659,6 +685,14 @@ pressure_open(struct sol_flow_node *node, void *data, const struct sol_flow_node
     SOL_INT_CHECK_GOTO(ret, >= (int)sizeof(mdata->iio_base.config.sampling_frequency_name), err);
     SOL_INT_CHECK_GOTO(ret, < 0, err);
 
+    struct sol_str_table table[] = {
+        SOL_STR_TABLE_ITEM("in_pressure_",
+            opts->oversampling_ratio),
+        { }
+    };
+
+    mdata->iio_base.config.oversampling_ratio_table = table;
+
     if (mdata->iio_base.buffer_enabled) {
         mdata->iio_base.config.sol_iio_reader_cb = type->reader_cb;
         mdata->iio_base.config.data = node;