Add fanctl to skeleton

fanctl replaces pyfanctl. It provides fan control service with
dbus object "/org/openbmc/control/fans".

Currently there are two methods: setMax() to set all fans' speed to maximum,
and updatePresent() to update the "Present" status of inventory objects:
"/org/openbmc/inventory/system/chassis/fan*".

In future, more methods will be added, like setting fan speed based on
temperature sensor reading.

Fixes openbmc/openbmc#93

Change-Id: Ic65089f5d0538cd5e17cfcd9f27e652ae6080ec5
Signed-off-by: Yi Li <adamliyi@msn.com>
diff --git a/fanctl/fan_control.c b/fanctl/fan_control.c
new file mode 100644
index 0000000..54b96b1
--- /dev/null
+++ b/fanctl/fan_control.c
@@ -0,0 +1,504 @@
+/**
+ * Copyright © 2016 IBM Corporation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <errno.h>
+#include <string.h>
+#include <getopt.h>
+#include <systemd/sd-bus.h>
+
+#define DBUS_MAX_NAME_LEN 256
+
+const char *objectmapper_service_name =  "org.openbmc.ObjectMapper";
+const char *objectmapper_object_name  =  "/org/openbmc/ObjectMapper";
+const char *objectmapper_intf_name    =  "org.openbmc.ObjectMapper";
+
+typedef struct {
+	int fan_num;
+	int cpu_num;
+	int core_num;
+	int dimm_num;
+	sd_bus *bus;
+	char sensor_service[DBUS_MAX_NAME_LEN];
+	char inventory_service[DBUS_MAX_NAME_LEN];
+} fan_info_t;
+
+/* Get an object's bus name from ObjectMapper */
+int get_connection(sd_bus *bus, char *connection, const char *obj_path)
+{
+	sd_bus_error bus_error = SD_BUS_ERROR_NULL;
+	sd_bus_message *m = NULL;
+	char *temp_buf = NULL, *intf = NULL;
+	int rc;
+
+	rc = sd_bus_call_method(bus,
+				objectmapper_service_name,
+				objectmapper_object_name,
+				objectmapper_intf_name,
+				"GetObject",
+				&bus_error,
+				&m,
+				"s",
+				obj_path);
+	if (rc < 0) {
+		fprintf(stderr,
+			"Failed to GetObject: %s\n", bus_error.message);
+		goto finish;
+	}
+
+	/* Get the key, aka, the bus name */
+	sd_bus_message_read(m, "a{sas}", 1, &temp_buf, 1, &intf);
+	strncpy(connection, temp_buf, DBUS_MAX_NAME_LEN);
+
+finish:
+	sd_bus_error_free(&bus_error);
+	sd_bus_message_unref(m);
+	sd_bus_flush(bus);
+
+	return rc;
+}
+
+
+int set_dbus_sensor(sd_bus *bus, const char *obj_path, int val)
+{
+	char connection[DBUS_MAX_NAME_LEN];
+	sd_bus_error bus_error = SD_BUS_ERROR_NULL;
+	sd_bus_message *response = NULL;
+	int rc;
+
+	if (!bus || !obj_path)
+		return -1;
+
+	rc = get_connection(bus, connection, obj_path);
+	if (rc < 0) {
+		fprintf(stderr,
+			"fanctl: Failed to get bus name for %s\n", obj_path);
+		goto finish;
+	}
+
+	rc = sd_bus_call_method(bus,
+				connection,
+				obj_path,
+				"org.openbmc.SensorValue",
+				"setValue",
+				&bus_error,
+				&response,
+				"i",
+				val);
+	if (rc < 0)
+		fprintf(stderr,
+			"fanctl: Failed to set sensor %s:[%s]\n",
+			obj_path, strerror(-rc));
+
+finish:
+	sd_bus_error_free(&bus_error);
+	sd_bus_message_unref(response);
+	sd_bus_flush(bus);
+
+	return rc;
+}
+
+/* Read sensor value from "org.openbmc.Sensors" */
+int read_dbus_sensor(sd_bus *bus, const char *obj_path)
+{
+	char connection[DBUS_MAX_NAME_LEN];
+	sd_bus_error bus_error = SD_BUS_ERROR_NULL;
+	sd_bus_message *response = NULL;
+	int rc;
+	int val = 0;
+
+	if (!bus || !obj_path)
+		return 0;
+
+	rc = get_connection(bus, connection, obj_path);
+	if (rc < 0) {
+		val = 0;
+		fprintf(stderr,
+			"fanctl: Failed to get bus name for %s\n", obj_path);
+		goto finish;
+	}
+
+	rc = sd_bus_call_method(bus,
+				connection,
+				obj_path,
+				"org.openbmc.SensorValue",
+				"getValue",
+				&bus_error,
+				&response,
+				NULL);
+	if (rc < 0) {
+		val = 0;
+		fprintf(stderr,
+			"fanctl: Failed to read sensor value from %s:[%s]\n",
+			obj_path, strerror(-rc));
+		goto finish;
+	}
+
+	rc = sd_bus_message_read(response, "v","i", &val);
+	if (rc < 0) {
+		val = 0;
+		fprintf(stderr,
+			"fanctl: Failed to parse sensor value "
+			"response message from %s:[%s]\n",
+			obj_path, strerror(-rc));
+	}
+
+finish:
+	sd_bus_error_free(&bus_error);
+	sd_bus_message_unref(response);
+	sd_bus_flush(bus);
+
+	return val;
+}
+
+/* set fan speed with /org/openbmc/sensors/speed/fan* object */
+static int fan_set_speed(sd_bus *bus, int fan_id, uint8_t fan_speed)
+{
+	char obj_path[DBUS_MAX_NAME_LEN];
+	int rc;
+
+	if (!bus)
+		return -1;
+
+	snprintf(obj_path, sizeof(obj_path),
+		"/org/openbmc/sensors/speed/fan%d", fan_id);
+	rc = set_dbus_sensor(bus, obj_path, fan_speed);
+	if (rc < 0)
+		fprintf(stderr, "fanctl: Failed to set fan[%d] speed[%d]\n",
+				fan_id, fan_speed);
+
+	return rc;
+}
+
+static int fan_set_max_speed(fan_info_t *info)
+{
+	int i;
+	int rc = -1;
+
+	if (!info)
+		return -1;
+	for (i = 0; i < info->fan_num; i++) {
+		rc = fan_set_speed(info->bus, i, 255);
+		if (rc < 0)
+			break;
+		fprintf(stderr, "fanctl: Set fan%d to max speed\n", i);
+	}
+
+	return rc;
+}
+/*
+ * FAN_TACH_OFFSET is specific to Barreleye.
+ * Barreleye uses NTC7904D HW Monitor as Fan tachometoer.
+ * The 13-bit FANIN value is made up Higer part: [12:5],
+ * and Lower part: [4:0], which are read from two sensors.
+ * see: https://www.nuvoton.com/resource-files/NCT7904D_Datasheet_V1.44.pdf
+ */
+#define FAN_TACH_OFFSET 5
+static int fan_get_speed(sd_bus *bus, int fan_id)
+{
+	int fan_tach_H = 0, fan_tach_L = 0;
+	char obj_path[DBUS_MAX_NAME_LEN];
+	int fan_speed;
+
+	/* get fan tach */
+	/* The object path is specific to Barreleye */
+	snprintf(obj_path, sizeof(obj_path),
+		"/org/openbmc/sensors/tach/fan%dH", fan_id);
+	fan_tach_H = read_dbus_sensor(bus, obj_path);
+	snprintf(obj_path, sizeof(obj_path),
+		"/org/openbmc/sensors/tach/fan%dL", fan_id);
+	fan_tach_L = read_dbus_sensor(bus, obj_path);
+
+	/* invalid sensor value is -1 */
+	if (fan_tach_H <= 0 || fan_tach_L <= 0)
+		fan_speed = 0;
+	else
+		fan_speed = fan_tach_H << FAN_TACH_OFFSET | fan_tach_L;
+
+	fprintf(stderr, "fan%d speed: %d\n", fan_id, fan_speed);
+	return fan_speed;
+}
+
+/* set Fan Inventory 'Present' status */
+int fan_set_present(sd_bus *bus, int fan_id, int val)
+{
+	sd_bus_error bus_error = SD_BUS_ERROR_NULL;
+	sd_bus_message *response = NULL;
+	int rc;
+	char obj_path[DBUS_MAX_NAME_LEN];
+	char connection[DBUS_MAX_NAME_LEN];
+
+	snprintf(obj_path, sizeof(obj_path),
+		"/org/openbmc/inventory/system/chassis/fan%d", fan_id);
+
+	rc = get_connection(bus, connection, obj_path);
+	if (rc < 0) {
+		fprintf(stderr,
+			"fanctl: Failed to get bus name for %s\n", obj_path);
+		goto finish;
+	}
+
+	rc = sd_bus_call_method(bus,
+				connection,
+				obj_path,
+				"org.openbmc.InventoryItem",
+				"setPresent",
+				&bus_error,
+				&response,
+				"s",
+				(val == 1 ? "True" : "False"));
+	if(rc < 0)
+		fprintf(stderr,
+			"fanctl: Failed to update fan presence via dbus: %s\n",
+			bus_error.message);
+
+	fprintf(stderr, "fanctl: Set fan%d present status to: %s\n",
+			fan_id, (val == 1 ? "True" : "False"));
+
+finish:
+	sd_bus_error_free(&bus_error);
+	sd_bus_message_unref(response);
+	sd_bus_flush(bus);
+
+	return rc;
+}
+
+/*
+ * Update Fan Invertory 'Present' status by first reading fan speed.
+ * If fan speed is '0', the fan is considerred not 'Present'.
+ */
+static int fan_update_present(fan_info_t *info)
+{
+	int i;
+	int rc = -1;
+	int fan_speed;
+
+	if (!info)
+		return -1;
+
+	for (i = 0; i < info->fan_num; i++) {
+		fan_speed = fan_get_speed(info->bus, i);
+		if (fan_speed > 0)
+			rc = fan_set_present(info->bus, i, 1);
+		else
+			rc = fan_set_present(info->bus, i, 0);
+
+		if (rc < 0) {
+			fprintf(stderr,
+				"fanctl: Failed to set fan present status\n");
+			break;
+		}
+	}
+
+	return rc;
+}
+/*
+ * Router function for any FAN operations that come via dbus
+ */
+static int fan_function_router(sd_bus_message *msg, void *user_data,
+		sd_bus_error *ret_error)
+{
+	/* Generic error reporter. */
+	int rc = -1;
+	fan_info_t *info = user_data;
+
+	/* Get the Operation. */
+	const char *fan_function = sd_bus_message_get_member(msg);
+	if (fan_function == NULL) {
+		fprintf(stderr, "fanctl: Null FAN function specificed\n");
+		return sd_bus_reply_method_return(msg, "i", rc);
+	}
+
+	/* Route the user action to appropriate handlers. */
+	if ((strcmp(fan_function, "setMax") == 0)) {
+		rc = fan_set_max_speed(info);
+		return sd_bus_reply_method_return(msg, "i", rc);
+	}
+	if ((strcmp(fan_function, "updatePresent") == 0)) {
+		rc = fan_update_present(info);
+		return sd_bus_reply_method_return(msg, "i", rc);
+	}
+
+	return sd_bus_reply_method_return(msg, "i", rc);
+}
+
+/* Dbus Services offered by this FAN controller */
+static const sd_bus_vtable fan_control_vtable[] =
+{
+	SD_BUS_VTABLE_START(0),
+	SD_BUS_METHOD("setMax", "", "i", &fan_function_router,
+			SD_BUS_VTABLE_UNPRIVILEGED),
+	SD_BUS_METHOD("updatePresent", "", "i", &fan_function_router,
+			SD_BUS_VTABLE_UNPRIVILEGED),
+	SD_BUS_VTABLE_END,
+};
+
+int start_fan_services(fan_info_t *info)
+{
+	/* Generic error reporter. */
+	int rc = -1;
+	/* slot where we are offering the FAN dbus service. */
+	sd_bus_slot *fan_slot = NULL;
+	const char *fan_object = "/org/openbmc/control/fans";
+
+	info->bus = NULL;
+	/* Get a hook onto system bus. */
+	rc = sd_bus_open_system(&info->bus);
+	if (rc < 0) {
+		fprintf(stderr,"fanctl: Error opening system bus.\n");
+		return rc;
+	}
+
+	/* Install the object */
+	rc = sd_bus_add_object_vtable(info->bus,
+			&fan_slot,
+			fan_object, /* object path */
+			"org.openbmc.control.Fans", /* interface name */
+			fan_control_vtable,
+			info);
+	if (rc < 0) {
+		fprintf(stderr, "fanctl: Failed to add object to dbus: %s\n",
+				strerror(-rc));
+		return rc;
+	}
+
+	/* If we had success in adding the providers, request for a bus name. */
+	rc = sd_bus_request_name(info->bus,
+			"org.openbmc.control.Fans", 0);
+	if (rc < 0) {
+		fprintf(stderr, "fanctl: Failed to acquire service name: %s\n",
+				strerror(-rc));
+		return rc;
+	}
+
+	for (;;) {
+		/* Process requests */
+		rc = sd_bus_process(info->bus, NULL);
+		if (rc < 0) {
+			fprintf(stderr, "fanctl: Failed to process bus: %s\n",
+					strerror(-rc));
+			break;
+		}
+		if (rc > 0) {
+			continue;
+		}
+
+		rc = sd_bus_wait(info->bus, (uint64_t) - 1);
+		if (rc < 0) {
+			fprintf(stderr, "fanctl: Failed to wait on bus: %s\n",
+				strerror(-rc));
+			break;
+		}
+	}
+
+	sd_bus_slot_unref(fan_slot);
+	sd_bus_unref(info->bus);
+
+	return rc;
+}
+
+static int str_to_int(char *str)
+{
+	long val;
+	char *temp;
+
+	val = strtol(str, &temp, 10);
+	if (temp == str || *temp != '\0' ||
+		((val == LONG_MIN || val == LONG_MAX) && errno == ERANGE))
+		return -1;
+	if (val < 0)
+		return -1;
+
+	return (int)val;
+}
+
+static int parse_argument(int argc, char **argv, fan_info_t *info)
+{
+	int c;
+	struct option long_options[] =
+	{
+		{"fan_num",  required_argument, 0, 'f'},
+		{"core_num",    required_argument, 0, 'c'},
+		{"cpu_num",    required_argument, 0, 'p'},
+		{"dimm_num",    required_argument, 0, 'd'},
+		{0, 0, 0, 0}
+	};
+
+	while (1) {
+		c = getopt_long (argc, argv, "c:d:f:p:", long_options, NULL);
+
+		/* Detect the end of the options. */
+		if (c == -1)
+			break;
+
+		switch (c) {
+		case 'f':
+			info->fan_num = str_to_int(optarg);
+			if (info->fan_num == -1) {
+				fprintf(stderr, "fanctl: Wrong fan_num: %s\n", optarg);
+				return -1;
+			}
+			break;
+		case 'c':
+			info->core_num = str_to_int(optarg);
+			if (info->core_num == -1) {
+				fprintf(stderr, "fanctl: Wrong core_num: %s\n", optarg);
+				return -1;
+			}
+			break;
+		case 'p':
+			info->cpu_num = str_to_int(optarg);
+			if (info->cpu_num == -1) {
+				fprintf(stderr, "fanctl: Wrong cpu_num: %s\n", optarg);
+				return -1;
+			}
+			break;
+		case 'd':
+			info->dimm_num = str_to_int(optarg);
+			if (info->dimm_num == -1) {
+				fprintf(stderr, "fanctl: Wrong dimm_num: %s\n", optarg);
+				return -1;
+			}
+			break;
+		default:
+			fprintf(stderr, "fanctl: Wrong argument\n");
+			return -1;
+		}
+	}
+
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	int rc = 0;
+	fan_info_t fan_info;
+
+	memset(&fan_info, 0, sizeof(fan_info));
+	rc = parse_argument(argc, argv, &fan_info);
+	if (rc < 0) {
+		fprintf(stderr, "fanctl: Error parse argument\n");
+		return rc;
+	}
+	/* This call is not supposed to return. If it does, then an error */
+	rc = start_fan_services(&fan_info);
+	if (rc < 0) {
+		fprintf(stderr, "fanctl: Error starting FAN Services. Exiting");
+	}
+
+	return rc;
+}