main: Add IIO polling Light Sensor driver

src/Makefile.am

@@ -8,7 +8,8 @@ iio_sensor_proxy_SOURCES =			\
 	drv-iio-buffer-accel.c			\
 	drv-iio-poll-accel.c			\
 	drv-input-accel.c			\
-	drv-fake-light.c
+	drv-fake-light.c			\
+	drv-iio-poll-light.c
 
 iio_sensor_proxy_CPPFLAGS =			\
 	$(IIO_SENSOR_PROXY_CFLAGS)		\

src/drivers.h

@@ -60,3 +60,4 @@ extern SensorDriver iio_buffer_accel;
 extern SensorDriver iio_poll_accel;
 extern SensorDriver input_accel;
 extern SensorDriver fake_light;
+extern SensorDriver iio_poll_light;

src/drv-iio-poll-light.c

@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) 2014 Bastien Nocera <hadess@hadess.net>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ */
+
+#include "drivers.h"
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <errno.h>
+#include <stdio.h>
+
+#define DEFAULT_POLL_TIME 0.8
+
+typedef struct DrvData {
+	ReadingsUpdateFunc  callback_func;
+	gpointer            user_data;
+
+	char               *input_path;
+	guint               timeout_id;
+} DrvData;
+
+static DrvData *drv_data = NULL;
+
+static gboolean
+iio_poll_light_discover (GUdevDevice *device)
+{
+	char *path;
+	gboolean ret;
+
+	if (g_strcmp0 (g_udev_device_get_subsystem (device), "iio") != 0)
+		return FALSE;
+
+	path = g_build_filename (g_udev_device_get_sysfs_path (device),
+				 "in_illuminance_input",
+				 NULL);
+	ret = g_file_test (path, G_FILE_TEST_IS_REGULAR);
+	g_free (path);
+
+	if (ret)
+		g_debug ("Found IIO poll light at %s", g_udev_device_get_sysfs_path (device));
+	return ret;
+}
+
+static gboolean
+light_changed (void)
+{
+	LightReadings readings;
+	gdouble level;
+	char *contents;
+	GError *error = NULL;
+
+	if (g_file_get_contents (drv_data->input_path, &contents, NULL, &error)) {
+		level = g_ascii_strtod (contents, NULL);
+		g_free (contents);
+	} else {
+		g_warning ("Failed to read input level at %s: %s",
+			   drv_data->input_path, error->message);
+		g_error_free (error);
+		return G_SOURCE_CONTINUE;
+	}
+
+	readings.level = level;
+	readings.uses_lux = TRUE;
+	drv_data->callback_func (&iio_poll_light, (gpointer) &readings, drv_data->user_data);
+
+	return G_SOURCE_CONTINUE;
+}
+
+static guint
+get_interval (GUdevDevice *device)
+{
+	gdouble time;
+	char *path, *contents;
+
+	path = g_build_filename (g_udev_device_get_sysfs_path (device),
+				 "in_illuminance_integration_time",
+				 NULL);
+	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);
+
+	return (time * 1000);
+}
+
+static gboolean
+iio_poll_light_open (GUdevDevice        *device,
+		     ReadingsUpdateFunc  callback_func,
+		     gpointer            user_data)
+{
+	guint interval;
+
+	drv_data = g_new0 (DrvData, 1);
+	drv_data->callback_func = callback_func;
+	drv_data->user_data = user_data;
+
+	interval = get_interval (device);
+	drv_data->input_path = g_build_filename (g_udev_device_get_sysfs_path (device),
+						 "in_illuminance_input",
+						 NULL);
+	drv_data->timeout_id = g_timeout_add (interval,
+					      (GSourceFunc) light_changed,
+					      NULL);
+
+	return TRUE;
+}
+
+static void
+iio_poll_light_close (void)
+{
+	if (drv_data->timeout_id != 0) {
+		g_source_remove (drv_data->timeout_id);
+		drv_data->timeout_id = 0;
+	}
+	g_clear_pointer (&drv_data->input_path, g_free);
+	g_clear_pointer (&drv_data, g_free);
+}
+
+SensorDriver iio_poll_light = {
+	.name = "IIO Buffer Light sensor",
+	.type = DRIVER_TYPE_LIGHT,
+	.specific_type = DRIVER_TYPE_LIGHT_IIO,
+
+	.discover = iio_poll_light_discover,
+	.open = iio_poll_light_open,
+	.close = iio_poll_light_close,
+};

src/iio-sensor-proxy.c

@@ -85,6 +85,7 @@ static const SensorDriver * const drivers[] = {
 	&iio_buffer_accel,
 	&iio_poll_accel,
 	&input_accel,
+	&iio_poll_light,
 	&fake_light
 };