iio:common:st_sensors: add st_sensors_get_settings_index() helper function

Extract from st_sensors_check_device_support() function the code that
is used to get the specific settings for a device. This will be used
as generic extractor by each ST driver.

Signed-off-by: Denis Ciocca <denis.ciocca@st.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/common/st_sensors/st_sensors_core.c b/drivers/iio/common/st_sensors/st_sensors_core.c
index 8b22dc2..3610ca9 100644 (file)
--- a/drivers/iio/common/st_sensors/st_sensors_core.c
+++ b/drivers/iio/common/st_sensors/st_sensors_core.c
@@ -633,28 +633,47 @@ static int st_sensors_init_interface_mode(struct iio_dev *indio_dev,
        return 0;
 }
 
+/*
+ * st_sensors_get_settings_index() - get index of the sensor settings for a
+ *                                  specific device from list of settings
+ * @name: device name buffer reference.
+ * @list: sensor settings list.
+ * @list_length: length of sensor settings list.
+ *
+ * Return: non negative number on success (valid index),
+ *        negative error code otherwise.
+ */
+int st_sensors_get_settings_index(const char *name,
+                                 const struct st_sensor_settings *list,
+                                 const int list_length)
+{
+       int i, n;
+
+       for (i = 0; i < list_length; i++) {
+               for (n = 0; n < ST_SENSORS_MAX_4WAI; n++) {
+                       if (strcmp(name, list[i].sensors_supported[n]) == 0)
+                               return i;
+               }
+       }
+
+       return -ENODEV;
+}
+EXPORT_SYMBOL(st_sensors_get_settings_index);
+
 int st_sensors_check_device_support(struct iio_dev *indio_dev,
                        int num_sensors_list,
                        const struct st_sensor_settings *sensor_settings)
 {
-       int i, n, err = 0;
-       u8 wai;
        struct st_sensor_data *sdata = iio_priv(indio_dev);
+       int i, err;
+       u8 wai;
 
-       for (i = 0; i < num_sensors_list; i++) {
-               for (n = 0; n < ST_SENSORS_MAX_4WAI; n++) {
-                       if (strcmp(indio_dev->name,
-                               sensor_settings[i].sensors_supported[n]) == 0) {
-                               break;
-                       }
-               }
-               if (n < ST_SENSORS_MAX_4WAI)
-                       break;
-       }
-       if (i == num_sensors_list) {
+       i = st_sensors_get_settings_index(indio_dev->name,
+                                         sensor_settings, num_sensors_list);
+       if (i < 0) {
                dev_err(&indio_dev->dev, "device name %s not recognized.\n",
-                                                       indio_dev->name);
-               return -ENODEV;
+                       indio_dev->name);
+               return i;
        }
 
        err = st_sensors_init_interface_mode(indio_dev, &sensor_settings[i]);

diff --git a/include/linux/iio/common/st_sensors.h b/include/linux/iio/common/st_sensors.h
index 2948ac9..17fbf3e 100644 (file)
--- a/include/linux/iio/common/st_sensors.h
+++ b/include/linux/iio/common/st_sensors.h
@@ -334,6 +334,10 @@ int st_sensors_set_fullscale_by_gain(struct iio_dev *indio_dev, int scale);
 int st_sensors_read_info_raw(struct iio_dev *indio_dev,
                                struct iio_chan_spec const *ch, int *val);
 
+int st_sensors_get_settings_index(const char *name,
+                                 const struct st_sensor_settings *list,
+                                 const int list_length);
+
 int st_sensors_check_device_support(struct iio_dev *indio_dev,
        int num_sensors_list, const struct st_sensor_settings *sensor_settings);