power: Add support for CPU_MAX_WAKE_LOCK.cm-7.1.0gingerbread-release

Change-Id: I93f15087a35ed9bbfcedf4c182ee80ebac4caae3

2 files changed, 87 insertions, 0 deletions

diff --git a/include/hardware_legacy/power.h b/include/hardware_legacy/power.h
index b7cee43..8b29f22 100644
--- a/include/hardware_legacy/power.h
+++ b/include/hardware_legacy/power.h
@@ -33,6 +33,10 @@ enum {
 int acquire_wake_lock(int lock, const char* id);
 int release_wake_lock(const char* id);
 
+//while you have a cpu lock held, the cpu freq will be held at max cpu freq
+int acquire_cpu_max_lock();
+int release_cpu_max_lock();
+
 // true if you want the screen on, false if you want it off
 int set_screen_state(int on);
 
diff --git a/power/power.c b/power/power.c
index 1dac44b..bca52fc 100644
--- a/power/power.c
+++ b/power/power.c
@@ -42,6 +42,17 @@ enum {
     OUR_FD_COUNT
 };
 
+enum {
+    CPU_SCALING_MAX_FREQ = 0,
+    CPU_SCALING_MIN_FREQ,
+    CPU_FD_COUNT
+};
+
+const char * const CPU_PATHS[] = {
+    "/sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq",
+    "/sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq"
+};
+
 const char * const OLD_PATHS[] = {
     "/sys/android_power/acquire_partial_wake_lock",
     "/sys/android_power/release_wake_lock",
@@ -61,6 +72,14 @@ static int g_initialized = 0;
 static int g_fds[OUR_FD_COUNT];
 static int g_error = 1;
 
+static int cpu_fds_initialized = 0;
+static int cpu_min_max_initialized = 0;
+static int cpu_fds[CPU_FD_COUNT];
+static int cpu_fds_error = 0;
+#define CPU_FREQ_MAX_SIZE 20
+static char cpu_scaling_max_freq_default[CPU_FREQ_MAX_SIZE];
+static char cpu_scaling_min_freq_default[CPU_FREQ_MAX_SIZE];
+
 static const char *off_state = "mem";
 static const char *on_state = "on";
 
@@ -106,6 +125,8 @@ initialize_fds(void)
     }
 }
 
+
+
 int
 acquire_wake_lock(int lock, const char* id)
 {
@@ -140,6 +161,68 @@ release_wake_lock(const char* id)
     return len >= 0;
 }
 
+static int
+open_cpu_file_descriptors()
+{
+    int i;
+    for (i=0; i<CPU_FD_COUNT; i++) {
+        int fd = open(CPU_PATHS[i], O_RDWR);
+        if (fd < 0) {
+            LOGE("fatal error opening \"%s\"\n", CPU_PATHS[i]);
+            cpu_fds_error = errno;
+            return -1;
+        }
+        cpu_fds[i] = fd;
+    }
+
+    cpu_fds_error = 0;
+    return 0;
+}
+
+static inline void
+initialize_cpu_fds(void)
+{
+    if (cpu_fds_initialized == 0)
+        if (open_cpu_file_descriptors() == 0)
+            cpu_fds_initialized = 1;
+}
+
+static inline void
+initialize_cpu_min_max(void)
+{
+    if(cpu_min_max_initialized == 0) {
+        read(cpu_fds[CPU_SCALING_MAX_FREQ],
+                cpu_scaling_max_freq_default, CPU_FREQ_MAX_SIZE);
+        read(cpu_fds[CPU_SCALING_MIN_FREQ],
+                cpu_scaling_min_freq_default, CPU_FREQ_MAX_SIZE);
+        cpu_min_max_initialized = 1;
+    }
+}
+
+int
+acquire_cpu_max_lock()
+{
+    initialize_cpu_fds();
+    if (cpu_fds_error) return cpu_fds_error;
+    initialize_cpu_min_max();
+
+    return write(cpu_fds[CPU_SCALING_MIN_FREQ],
+                cpu_scaling_max_freq_default, CPU_FREQ_MAX_SIZE);
+}
+
+int
+release_cpu_max_lock()
+{
+    initialize_cpu_fds();
+    if (cpu_fds_error) return cpu_fds_error;
+
+    if(cpu_min_max_initialized == 0) return 0;
+
+    return write(cpu_fds[CPU_SCALING_MIN_FREQ],
+                cpu_scaling_min_freq_default, CPU_FREQ_MAX_SIZE);
+}
+
+
 int
 set_last_user_activity_timeout(int64_t delay)
 {