Re-worked hardware_properties to thermal HAL.

Bug: 27424857
Change-Id: Id7212421e499cc33c82e885756d68e89c2317acf
diff --git a/modules/Android.mk b/modules/Android.mk
index 3dc4ca6..3bd0943 100644
--- a/modules/Android.mk
+++ b/modules/Android.mk
@@ -1,4 +1,4 @@
 hardware_modules := gralloc hwcomposer audio nfc nfc-nci local_time \
 	power usbaudio audio_remote_submix camera usbcamera consumerir sensors vibrator \
-	tv_input fingerprint input vehicle hardware_properties vr
+	tv_input fingerprint input vehicle thermal vr
 include $(call all-named-subdir-makefiles,$(hardware_modules))
diff --git a/modules/hardware_properties/hardware_properties.c b/modules/hardware_properties/hardware_properties.c
deleted file mode 100644
index 89ef423..0000000
--- a/modules/hardware_properties/hardware_properties.c
+++ /dev/null
@@ -1,72 +0,0 @@
-/*
- * Copyright (C) 2015 The Android Open Source Project
- *
- * 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 <errno.h>
-#include <stdlib.h>
-#include <string.h>
-
-#define LOG_TAG "HardwarePropertiesHAL"
-#include <utils/Log.h>
-
-#include <hardware/hardware.h>
-#include <hardware/hardware_properties.h>
-
-static ssize_t get_device_temperatures(
-    struct hardware_properties_module *module, float **temps) {
-    *temps = NULL;
-    errno = ENOSYS;
-    ALOGE("getDeviceTemperatures: %s", strerror(errno));
-    return -1;
-}
-
-static ssize_t get_cpu_usages(struct hardware_properties_module *module,
-                              int64_t **active_times, int64_t **total_times) {
-    *active_times = NULL;
-    *total_times = NULL;
-    errno = ENOSYS;
-    ALOGE("getCpuUsages: %s", strerror(errno));
-    return -1;
-}
-
-static ssize_t get_fan_speeds(struct hardware_properties_module *module,
-                              float **fan_speeds) {
-    *fan_speeds = NULL;
-    errno = ENOSYS;
-    ALOGE("getFanSpeeds: %s", strerror(errno));
-    return -1;
-}
-
-static struct hw_module_methods_t hardware_properties_module_methods = {
-    .open = NULL,
-};
-
-struct hardware_properties_module HAL_MODULE_INFO_SYM = {
-    .common = {
-        .tag = HARDWARE_MODULE_TAG,
-        .module_api_version = HARDWARE_PROPERTIES_HARDWARE_MODULE_API_VERSION_0_1,
-        .hal_api_version = HARDWARE_HAL_API_VERSION,
-        .id = HARDWARE_PROPERTIES_HARDWARE_MODULE_ID,
-        .name = "Default Hardware Properties HAL",
-        .author = "The Android Open Source Project",
-        .methods = &hardware_properties_module_methods,
-    },
-
-    .getCpuTemperatures = get_device_temperatures,
-    .getGpuTemperatures = get_device_temperatures,
-    .getBatteryTemperatures = get_device_temperatures,
-    .getCpuUsages = get_cpu_usages,
-    .getFanSpeeds = get_fan_speeds,
-};
diff --git a/modules/hardware_properties/Android.mk b/modules/thermal/Android.mk
similarity index 83%
rename from modules/hardware_properties/Android.mk
rename to modules/thermal/Android.mk
index 41c02ea..80ad78a 100644
--- a/modules/hardware_properties/Android.mk
+++ b/modules/thermal/Android.mk
@@ -16,10 +16,11 @@
 
 include $(CLEAR_VARS)
 
-LOCAL_MODULE := hardware_properties.default
+LOCAL_MODULE := thermal.default
 LOCAL_MODULE_RELATIVE_PATH := hw
-LOCAL_SRC_FILES := hardware_properties.c
-LOCAL_SHARED_LIBRARIES := liblog
+LOCAL_SRC_FILES := thermal.c
+LOCAL_SHARED_LIBRARIES := liblog libcutils
 LOCAL_MODULE_TAGS := optional
+LOCAL_CFLAGS := -Wno-unused-parameter
 
 include $(BUILD_SHARED_LIBRARY)
diff --git a/modules/thermal/thermal.c b/modules/thermal/thermal.c
new file mode 100644
index 0000000..c45d87a
--- /dev/null
+++ b/modules/thermal/thermal.c
@@ -0,0 +1,181 @@
+/*
+ * Copyright (C) 2016 The Android Open Source Project
+ *
+ * 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 <errno.h>
+#include <ctype.h>
+#include <dirent.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define LOG_TAG "ThermalHAL"
+#include <utils/Log.h>
+
+#include <hardware/hardware.h>
+#include <hardware/thermal.h>
+
+#define CPU_LABEL               "CPU"
+#define MAX_LENGTH              50
+
+#define CPU_USAGE_FILE          "/proc/stat"
+#define TEMPERATURE_DIR         "/sys/class/thermal"
+#define THERMAL_DIR             "thermal_zone"
+#define CPU_ONLINE_FILE_FORMAT  "/sys/devices/system/cpu/cpu%d/online"
+#define UNKNOWN_LABEL           "UNKNOWN"
+
+static ssize_t get_temperatures(thermal_module_t *module, temperature_t *list, size_t size) {
+    char file_name[MAX_LENGTH];
+    FILE *file;
+    float temp;
+    size_t idx = 0;
+    DIR *dir;
+    struct dirent *de;
+
+    /** Read all available temperatures from
+     * /sys/class/thermal/thermal_zone[0-9]+/temp files.
+     * Don't guarantee that all temperatures are in Celsius. */
+    dir = opendir(TEMPERATURE_DIR);
+    if (dir == 0) {
+        ALOGE("%s: failed to open directory %s: %s", __func__, TEMPERATURE_DIR, strerror(-errno));
+        return -errno;
+    }
+
+    while ((de = readdir(dir))) {
+        if (!strncmp(de->d_name, THERMAL_DIR, strlen(THERMAL_DIR))) {
+            snprintf(file_name, MAX_LENGTH, "%s/%s/temp", TEMPERATURE_DIR, de->d_name);
+            file = fopen(file_name, "r");
+            if (file == NULL) {
+                continue;
+            }
+            if (1 != fscanf(file, "%f", &temp)) {
+                fclose(file);
+                continue;
+            }
+
+            if (list != NULL && idx < size) {
+                list[idx] = (temperature_t) {
+                    .name = UNKNOWN_LABEL,
+                    .type = DEVICE_TEMPERATURE_UNKNOWN,
+                    .current_value = temp,
+                    .throttling_threshold = UNKNOWN_TEMPERATURE,
+                    .shutdown_threshold = UNKNOWN_TEMPERATURE,
+                };
+            }
+            fclose(file);
+            idx++;
+        }
+    }
+    closedir(dir);
+    return idx;
+}
+
+static ssize_t get_cpu_usages(thermal_module_t *module, cpu_usage_t *list) {
+    int vals, cpu_num, online;
+    ssize_t read;
+    uint64_t user, nice, system, idle, active, total;
+    char *line = NULL;
+    size_t len = 0;
+    size_t size = 0;
+    char file_name[MAX_LENGTH];
+    FILE *cpu_file;
+    FILE *file = fopen(CPU_USAGE_FILE, "r");
+
+    if (file == NULL) {
+        ALOGE("%s: failed to open: %s", __func__, strerror(errno));
+        return -errno;
+    }
+
+    while ((read = getline(&line, &len, file)) != -1) {
+        // Skip non "cpu[0-9]" lines.
+        if (strnlen(line, read) < 4 || strncmp(line, "cpu", 3) != 0 || !isdigit(line[3])) {
+            free(line);
+            line = NULL;
+            len = 0;
+            continue;
+        }
+        vals = sscanf(line, "cpu%d %" SCNu64 " %" SCNu64 " %" SCNu64 " %" SCNu64, &cpu_num, &user,
+                &nice, &system, &idle);
+
+        free(line);
+        line = NULL;
+        len = 0;
+
+        if (vals != 5) {
+            ALOGE("%s: failed to read CPU information from file: %s", __func__, strerror(errno));
+            fclose(file);
+            return errno ? -errno : -EIO;
+        }
+
+        active = user + nice + system;
+        total = active + idle;
+
+        // Read online CPU information.
+        snprintf(file_name, MAX_LENGTH, CPU_ONLINE_FILE_FORMAT, cpu_num);
+        cpu_file = fopen(file_name, "r");
+        online = 0;
+        if (cpu_file == NULL) {
+            ALOGE("%s: failed to open file: %s (%s)", __func__, file_name, strerror(errno));
+            // /sys/devices/system/cpu/cpu0/online is missing on some systems, because cpu0 can't
+            // be offline.
+            online = cpu_num == 0;
+        } else if (1 != fscanf(cpu_file, "%d", &online)) {
+            ALOGE("%s: failed to read CPU online information from file: %s (%s)", __func__,
+                    file_name, strerror(errno));
+            fclose(file);
+            fclose(cpu_file);
+            return errno ? -errno : -EIO;
+        }
+        fclose(cpu_file);
+
+        if (list != NULL) {
+            list[size] = (cpu_usage_t) {
+                .name = CPU_LABEL,
+                .active = active,
+                .total = total,
+                .is_online = online
+            };
+        }
+
+        size++;
+    }
+
+    fclose(file);
+    return size;
+}
+
+static ssize_t get_cooling_devices(thermal_module_t *module, cooling_device_t *list, size_t size) {
+    return 0;
+}
+
+static struct hw_module_methods_t thermal_module_methods = {
+    .open = NULL,
+};
+
+thermal_module_t HAL_MODULE_INFO_SYM = {
+    .common = {
+        .tag = HARDWARE_MODULE_TAG,
+        .module_api_version = THERMAL_HARDWARE_MODULE_API_VERSION_0_1,
+        .hal_api_version = HARDWARE_HAL_API_VERSION,
+        .id = THERMAL_HARDWARE_MODULE_ID,
+        .name = "Default Thermal HAL",
+        .author = "The Android Open Source Project",
+        .methods = &thermal_module_methods,
+    },
+
+    .getTemperatures = get_temperatures,
+    .getCpuUsages = get_cpu_usages,
+    .getCoolingDevices = get_cooling_devices,
+};