msm8939: Add power HAL extension to disable big cluster

* Taken from oppo msm8939
* Tweak min_cpus to match oppo msm8939 as well

Change-Id: Ice639dc225543a1d78e9dfca7382d2e40ceb5d0c

1 files changed, 52 insertions, 0 deletions

diff --git a/power/power_ext.c b/power/power_ext.c
new file mode 100644
index 0000000..1f85d8d
--- /dev/null
+++ b/power/power_ext.c
@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2016 The CyanogenMod 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>
+#include <fcntl.h>
+
+#define LOG_TAG "PowerHAL_MSM8939_Ext"
+#include <utils/Log.h>
+
+#define BIG_MAX_CPU_PATH "/sys/devices/system/cpu/cpu0/core_ctl/max_cpus"
+
+static void sysfs_write(char *path, char *s)
+{
+    char buf[80];
+    int len;
+    int fd;
+
+    if ((fd = open(path, O_WRONLY)) < 0) {
+        strerror_r(errno, buf, sizeof(buf));
+        ALOGE("Error opening %s: %s\n", path, buf);
+        return;
+    }
+
+    len = write(fd, s, strlen(s));
+    if (len < 0) {
+        strerror_r(errno, buf, sizeof(buf));
+        ALOGE("Error writing to %s: %s\n", path, buf);
+    }
+
+    close(fd);
+}
+
+void cm_power_set_interactive_ext(int on)
+{
+    ALOGD("%sabling big CPU cluster", on ? "En" : "Dis");
+    sysfs_write(BIG_MAX_CPU_PATH, on ? "4" : "0");
+}