power: Simplify soc_id checks

- Get soc_id in a common util function
 - Return boolean values for the target-specific soc_id checks

Change-Id: I038c435d28855859f36566de7acf881037d070f2

utils.c

@@ -43,6 +43,9 @@
 #define LOG_TAG "QTI PowerHAL"
 #include <log/log.h>
 
+#define SOC_ID_0 "/sys/devices/soc0/soc_id"
+#define SOC_ID_1 "/sys/devices/system/soc/soc0/id"
+
 char scaling_gov_path[4][80] = {"sys/devices/system/cpu/cpu0/cpufreq/scaling_governor",
                                 "sys/devices/system/cpu/cpu1/cpufreq/scaling_governor",
                                 "sys/devices/system/cpu/cpu2/cpufreq/scaling_governor",
@@ -341,3 +344,24 @@ void undo_initial_hint_action() {
         }
     }
 }
+
+int get_soc_id(void) {
+    int fd;
+    int soc_id = -1;
+    char buf[10] = {0};
+
+    if (!access(SOC_ID_0, F_OK))
+        fd = open(SOC_ID_0, O_RDONLY);
+    else
+        fd = open(SOC_ID_1, O_RDONLY);
+
+    if (fd >= 0) {
+        if (read(fd, buf, sizeof(buf) - 1) == -1)
+            ALOGW("Unable to read soc_id");
+        else
+            soc_id = atoi(buf);
+    }
+
+    close(fd);
+    return soc_id;
+}