light: Add support for "illuminance0" light sensors

That would be used in the tsl2772 and lm3533 kernel drivers, as well as
devices with multiple channels, such as combined proximity and light
sensors, which use "illuminance0" as the channel name instead of
"illuminance".

Closes: #290

Author: hadess

data/80-iio-sensor-proxy.rules

@@ -9,6 +9,7 @@ SUBSYSTEM=="iio", TEST=="in_accel_x_raw", TEST=="in_accel_y_raw", TEST=="in_acce
 SUBSYSTEM=="iio", TEST=="scan_elements/in_accel_x_en", TEST=="scan_elements/in_accel_y_en", TEST=="scan_elements/in_accel_z_en", ENV{IIO_SENSOR_PROXY_TYPE}="iio-buffer-accel"
 SUBSYSTEM=="iio", TEST=="scan_elements/in_rot_from_north_magnetic_tilt_comp_en", ENV{IIO_SENSOR_PROXY_TYPE}="iio-buffer-compass"
 SUBSYSTEM=="iio", TEST=="in_illuminance_input", ENV{IIO_SENSOR_PROXY_TYPE}="iio-poll-als"
+SUBSYSTEM=="iio", TEST=="in_illuminance0_input", ENV{IIO_SENSOR_PROXY_TYPE}="iio-poll-als"
 SUBSYSTEM=="iio", TEST=="in_illuminance_raw", ENV{IIO_SENSOR_PROXY_TYPE}="iio-poll-als"
 SUBSYSTEM=="iio", TEST=="scan_elements/in_intensity_both_en", ENV{IIO_SENSOR_PROXY_TYPE}="iio-buffer-als"
 SUBSYSTEM=="input", ENV{ID_INPUT_ACCELEROMETER}=="1", ENV{IIO_SENSOR_PROXY_TYPE}="input-accel"

src/drv-iio-poll-light.c

@@ -71,23 +71,45 @@ light_changed (gpointer user_data)
 	return G_SOURCE_CONTINUE;
 }
 
+static char *
+get_illuminance_channel_path (GUdevDevice *device,
+			      const char *suffix)
+{
+	const char *channels[] = {
+		"in_illuminance",
+		"in_illuminance0"
+	};
+	char *path = NULL;
+	guint i;
+
+	for (i = 0; i < G_N_ELEMENTS (channels); i++) {
+		path = g_strdup_printf ("%s/%s_%s",
+					g_udev_device_get_sysfs_path (device),
+					channels[i],
+					suffix);
+		if (g_file_test (path, G_FILE_TEST_EXISTS))
+			return path;
+		g_clear_pointer (&path, g_free);
+	}
+	return NULL;
+}
+
 static guint
 get_interval (GUdevDevice *device)
 {
-	gdouble time;
+	gdouble time = DEFAULT_POLL_TIME;
 	char *path, *contents;
 
-	path = g_build_filename (g_udev_device_get_sysfs_path (device),
-				 "in_illuminance_integration_time",
-				 NULL);
+	path = get_illuminance_channel_path (device, "integration_time");
+	if (!path)
+		goto out;
 	if (g_file_get_contents (path, &contents, NULL, NULL)) {
 		time = g_ascii_strtod (contents, NULL);
 		g_free (contents);
-	} else {
-		time = DEFAULT_POLL_TIME;
 	}
 	g_free (path);
 
+out:
 	return (time * 1000);
 }
 
@@ -124,17 +146,19 @@ iio_poll_light_open (GUdevDevice        *device,
 	drv_data->user_data = user_data;
 
 	drv_data->interval = get_interval (device);
-	drv_data->input_path = g_build_filename (g_udev_device_get_sysfs_path (device),
-						 "in_illuminance_input",
-						 NULL);
-	if (!g_file_test (drv_data->input_path, G_FILE_TEST_EXISTS)) {
-		g_free (drv_data->input_path);
-		drv_data->input_path = g_build_filename (g_udev_device_get_sysfs_path (device),
-							 "in_illuminance_raw",
-							 NULL);
-	}
+	drv_data->input_path = get_illuminance_channel_path (device, "input");
+	if (!drv_data->input_path)
+		drv_data->input_path = get_illuminance_channel_path (device, "raw");
+	if (!drv_data->input_path)
+		return FALSE;
 
-	drv_data->scale = g_udev_device_get_sysfs_attr_as_double (device, "in_illuminance_scale");
+	if (g_str_has_prefix (drv_data->input_path, "in_illuminance0")) {
+		drv_data->scale = g_udev_device_get_sysfs_attr_as_double (device,
+									  "in_illuminance0_scale");
+	} else {
+		drv_data->scale = g_udev_device_get_sysfs_attr_as_double (device,
+									  "in_illuminance_scale");
+	}
 	if (drv_data->scale == 0.0)
 		drv_data->scale = 1.0;