diff --git a/device.mk b/device.mk
index dbe41c6..51a810a 100644
--- a/device.mk
+++ b/device.mk
@@ -221,6 +221,9 @@ PRODUCT_PACKAGES += \
 PRODUCT_PACKAGES += \
     bdAddrLoader
 
+PRODUCT_PACKAGES += \
+    power.hammerhead
+
 PRODUCT_PROPERTY_OVERRIDES += \
     ro.opengles.version=196608
 
diff --git a/power/Android.mk b/power/Android.mk
new file mode 100644
index 0000000..60ffb11
--- /dev/null
+++ b/power/Android.mk
@@ -0,0 +1,25 @@
+#
+# Copyright 2014 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.
+#
+
+LOCAL_PATH:= $(call my-dir)
+
+include $(CLEAR_VARS)
+LOCAL_MODULE_RELATIVE_PATH := hw
+LOCAL_SRC_FILES := power_hammerhead.c
+LOCAL_SHARED_LIBRARIES := liblog libcutils
+LOCAL_MODULE_TAGS := optional
+LOCAL_MODULE := power.hammerhead
+include $(BUILD_SHARED_LIBRARY)
diff --git a/power/power_hammerhead.c b/power/power_hammerhead.c
new file mode 100644
index 0000000..d025f3a
--- /dev/null
+++ b/power/power_hammerhead.c
@@ -0,0 +1,409 @@
+/*
+ * Copyright (C) 2014 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 <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <fcntl.h>
+#include <dlfcn.h>
+#include <cutils/uevent.h>
+#include <errno.h>
+#include <sys/poll.h>
+#include <pthread.h>
+#include <linux/netlink.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+#define LOG_TAG "PowerHAL"
+#include <utils/Log.h>
+
+#include <hardware/hardware.h>
+#include <hardware/power.h>
+
+#define STATE_ON "state=1"
+#define STATE_OFF "state=0"
+#define STATE_HDR_ON "state=2"
+#define STATE_HDR_OFF "state=3"
+
+#define MAX_LENGTH         50
+#define BOOST_SOCKET       "/dev/socket/pb"
+
+#define UEVENT_MSG_LEN 1024
+#define TOTAL_CPUS 4
+#define RETRY_TIME_CHANGING_FREQ 20
+#define SLEEP_USEC_BETWN_RETRY 200
+#define LOW_POWER_MAX_FREQ "729600"
+#define LOW_POWER_MIN_FREQ "300000"
+#define NORMAL_MAX_FREQ "2265600"
+#define UEVENT_STRING "online@/devices/system/cpu/"
+
+static int client_sockfd;
+static struct sockaddr_un client_addr;
+static int last_state = -1;
+
+static struct pollfd pfd;
+static char *cpu_path_min[] = {
+    "/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq",
+    "/sys/devices/system/cpu/cpu1/cpufreq/scaling_min_freq",
+    "/sys/devices/system/cpu/cpu2/cpufreq/scaling_min_freq",
+    "/sys/devices/system/cpu/cpu3/cpufreq/scaling_min_freq",
+};
+static char *cpu_path_max[] = {
+    "/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq",
+    "/sys/devices/system/cpu/cpu1/cpufreq/scaling_max_freq",
+    "/sys/devices/system/cpu/cpu2/cpufreq/scaling_max_freq",
+    "/sys/devices/system/cpu/cpu3/cpufreq/scaling_max_freq",
+};
+static bool freq_set[TOTAL_CPUS];
+static bool low_power_mode = false;
+static pthread_mutex_t low_power_mode_lock = PTHREAD_MUTEX_INITIALIZER;
+
+static void socket_init()
+{
+    if (!client_sockfd) {
+        client_sockfd = socket(PF_UNIX, SOCK_DGRAM, 0);
+        if (client_sockfd < 0) {
+            ALOGE("%s: failed to open: %s", __func__, strerror(errno));
+            return;
+        }
+        memset(&client_addr, 0, sizeof(struct sockaddr_un));
+        client_addr.sun_family = AF_UNIX;
+        snprintf(client_addr.sun_path, UNIX_PATH_MAX, BOOST_SOCKET);
+    }
+}
+
+static int sysfs_write(const char *path, char *s)
+{
+    char buf[80];
+    int len;
+    int fd = open(path, O_WRONLY);
+
+    if (fd < 0) {
+        strerror_r(errno, buf, sizeof(buf));
+        ALOGE("Error opening %s: %s\n", path, buf);
+        return -1;
+    }
+
+    len = write(fd, s, strlen(s));
+    if (len < 0) {
+        strerror_r(errno, buf, sizeof(buf));
+        ALOGE("Error writing to %s: %s\n", path, buf);
+        return -1;
+    }
+
+    close(fd);
+    return 0;
+}
+
+static int uevent_event()
+{
+    char msg[UEVENT_MSG_LEN];
+    char *cp;
+    int n, cpu, ret, retry = RETRY_TIME_CHANGING_FREQ;
+
+    n = recv(pfd.fd, msg, UEVENT_MSG_LEN, MSG_DONTWAIT);
+    if (n <= 0) {
+        return -1;
+    }
+    if (n >= UEVENT_MSG_LEN) {   /* overflow -- discard */
+        return -1;
+    }
+
+    cp = msg;
+
+    if (strstr(cp, UEVENT_STRING)) {
+        n = strlen(cp);
+        errno = 0;
+        cpu = strtol(cp + n - 1, NULL, 10);
+
+        if (errno == EINVAL || errno == ERANGE || cpu < 0 || cpu >= TOTAL_CPUS) {
+            return -1;
+        }
+
+        pthread_mutex_lock(&low_power_mode_lock);
+        if (low_power_mode && !freq_set[cpu]) {
+            while (retry) {
+                sysfs_write(cpu_path_min[cpu], LOW_POWER_MIN_FREQ);
+                ret = sysfs_write(cpu_path_max[cpu], LOW_POWER_MAX_FREQ);
+                if (!ret) {
+                    freq_set[cpu] = true;
+                    break;
+                }
+                usleep(SLEEP_USEC_BETWN_RETRY);
+                retry--;
+           }
+        } else if (!low_power_mode && freq_set[cpu]) {
+             while (retry) {
+                  ret = sysfs_write(cpu_path_max[cpu], NORMAL_MAX_FREQ);
+                  if (!ret) {
+                      freq_set[cpu] = false;
+                      break;
+                  }
+                  usleep(SLEEP_USEC_BETWN_RETRY);
+                  retry--;
+             }
+        }
+        pthread_mutex_unlock(&low_power_mode_lock);
+    }
+    return 0;
+}
+
+void *thread_uevent(__attribute__((unused)) void *x)
+{
+    while (1) {
+        int nevents, ret;
+
+        nevents = poll(&pfd, 1, -1);
+
+        if (nevents == -1) {
+            if (errno == EINTR)
+                continue;
+            ALOGE("powerhal: thread_uevent: poll_wait failed\n");
+            break;
+        }
+        ret = uevent_event();
+        if (ret < 0)
+            ALOGE("Error processing the uevent event");
+    }
+    return NULL;
+}
+
+static void uevent_init()
+{
+    struct sockaddr_nl client;
+    pthread_t tid;
+    pfd.fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);
+
+    if (pfd.fd < 0) {
+        ALOGE("%s: failed to open: %s", __func__, strerror(errno));
+        return;
+    }
+    memset(&client, 0, sizeof(struct sockaddr_nl));
+    pthread_create(&tid, NULL, thread_uevent, NULL);
+    client.nl_family = AF_NETLINK;
+    client.nl_pid = tid;
+    client.nl_groups = -1;
+    pfd.events = POLLIN;
+    bind(pfd.fd, (void *)&client, sizeof(struct sockaddr_nl));
+    return;
+}
+
+static void power_init(__attribute__((unused)) struct power_module *module)
+{
+    ALOGI("%s", __func__);
+    socket_init();
+    uevent_init();
+}
+
+static void sync_thread(int off)
+{
+    int rc;
+    pid_t client;
+    char data[MAX_LENGTH];
+
+    if (client_sockfd < 0) {
+        ALOGE("%s: boost socket not created", __func__);
+        return;
+    }
+
+    client = getpid();
+
+    if (!off) {
+        snprintf(data, MAX_LENGTH, "2:%d", client);
+        rc = sendto(client_sockfd, data, strlen(data), 0,
+            (const struct sockaddr *)&client_addr, sizeof(struct sockaddr_un));
+    } else {
+        snprintf(data, MAX_LENGTH, "3:%d", client);
+        rc = sendto(client_sockfd, data, strlen(data), 0,
+            (const struct sockaddr *)&client_addr, sizeof(struct sockaddr_un));
+    }
+
+    if (rc < 0) {
+        ALOGE("%s: failed to send: %s", __func__, strerror(errno));
+    }
+}
+
+static void enc_boost(int off)
+{
+    int rc;
+    pid_t client;
+    char data[MAX_LENGTH];
+
+    if (client_sockfd < 0) {
+        ALOGE("%s: boost socket not created", __func__);
+        return;
+    }
+
+    client = getpid();
+
+    if (!off) {
+        snprintf(data, MAX_LENGTH, "5:%d", client);
+        rc = sendto(client_sockfd, data, strlen(data), 0,
+            (const struct sockaddr *)&client_addr, sizeof(struct sockaddr_un));
+    } else {
+        snprintf(data, MAX_LENGTH, "6:%d", client);
+        rc = sendto(client_sockfd, data, strlen(data), 0,
+            (const struct sockaddr *)&client_addr, sizeof(struct sockaddr_un));
+    }
+
+    if (rc < 0) {
+        ALOGE("%s: failed to send: %s", __func__, strerror(errno));
+    }
+}
+
+static void process_video_encode_hint(void *metadata)
+{
+
+    socket_init();
+
+    if (client_sockfd < 0) {
+        ALOGE("%s: boost socket not created", __func__);
+        return;
+    }
+
+    if (metadata) {
+        if (!strncmp(metadata, STATE_ON, sizeof(STATE_ON))) {
+            /* Video encode started */
+            sync_thread(1);
+            enc_boost(1);
+        } else if (!strncmp(metadata, STATE_OFF, sizeof(STATE_OFF))) {
+            /* Video encode stopped */
+            sync_thread(0);
+            enc_boost(0);
+        }  else if (!strncmp(metadata, STATE_HDR_ON, sizeof(STATE_HDR_ON))) {
+            /* HDR usecase started */
+        } else if (!strncmp(metadata, STATE_HDR_OFF, sizeof(STATE_HDR_OFF))) {
+            /* HDR usecase stopped */
+        }else
+            return;
+    } else {
+        return;
+    }
+}
+
+
+static void touch_boost()
+{
+    int rc;
+    pid_t client;
+    char data[MAX_LENGTH];
+
+    if (client_sockfd < 0) {
+        ALOGE("%s: boost socket not created", __func__);
+        return;
+    }
+
+    client = getpid();
+
+    snprintf(data, MAX_LENGTH, "1:%d", client);
+    rc = sendto(client_sockfd, data, strlen(data), 0,
+        (const struct sockaddr *)&client_addr, sizeof(struct sockaddr_un));
+    if (rc < 0) {
+        ALOGE("%s: failed to send: %s", __func__, strerror(errno));
+    }
+}
+
+static void power_set_interactive(__attribute__((unused)) struct power_module *module, int on)
+{
+    if (last_state == -1) {
+        last_state = on;
+    } else {
+        if (last_state == on)
+            return;
+        else
+            last_state = on;
+    }
+
+    ALOGV("%s %s", __func__, (on ? "ON" : "OFF"));
+    if (on) {
+        sync_thread(0);
+        touch_boost();
+    } else {
+        sync_thread(1);
+    }
+}
+
+static void power_hint( __attribute__((unused)) struct power_module *module,
+                      power_hint_t hint, __attribute__((unused)) void *data)
+{
+    int cpu, ret;
+
+    switch (hint) {
+        case POWER_HINT_INTERACTION:
+            ALOGV("POWER_HINT_INTERACTION");
+            touch_boost();
+            break;
+#if 0
+        case POWER_HINT_VSYNC:
+            ALOGV("POWER_HINT_VSYNC %s", (data ? "ON" : "OFF"));
+            break;
+#endif
+        case POWER_HINT_VIDEO_ENCODE:
+            process_video_encode_hint(data);
+            break;
+
+        case POWER_HINT_LOW_POWER:
+             pthread_mutex_lock(&low_power_mode_lock);
+             if (data) {
+                 low_power_mode = true;
+                 for (cpu = 0; cpu < TOTAL_CPUS; cpu++) {
+                     sysfs_write(cpu_path_min[cpu], LOW_POWER_MIN_FREQ);
+                     ret = sysfs_write(cpu_path_max[cpu], LOW_POWER_MAX_FREQ);
+                     if (!ret) {
+                         freq_set[cpu] = true;
+                     }
+                 }
+                 // reduces the refresh rate
+                 system("service call SurfaceFlinger 1016");
+             } else {
+                 low_power_mode = false;
+                 for (cpu = 0; cpu < TOTAL_CPUS; cpu++) {
+                     ret = sysfs_write(cpu_path_max[cpu], NORMAL_MAX_FREQ);
+                     if (!ret) {
+                         freq_set[cpu] = false;
+                     }
+                 }
+                 // restores the refresh rate
+                 system("service call SurfaceFlinger 1017");
+             }
+             pthread_mutex_unlock(&low_power_mode_lock);
+             break;
+        default:
+             break;
+    }
+}
+
+static struct hw_module_methods_t power_module_methods = {
+    .open = NULL,
+};
+
+struct power_module HAL_MODULE_INFO_SYM = {
+    .common = {
+        .tag = HARDWARE_MODULE_TAG,
+        .module_api_version = POWER_MODULE_API_VERSION_0_2,
+        .hal_api_version = HARDWARE_HAL_API_VERSION,
+        .id = POWER_HARDWARE_MODULE_ID,
+        .name = "Hammerhead Power HAL",
+        .author = "The Android Open Source Project",
+        .methods = &power_module_methods,
+    },
+
+    .init = power_init,
+    .setInteractive = power_set_interactive,
+    .powerHint = power_hint,
+};