update to new liblights by Stefan Seidel

[android-x86/hardware-liblights.git] / lights.c

diff --git a/lights.c b/lights.c
new file mode 100644 (file)
index 0000000..3d3a653
--- /dev/null
+++ b/lights.c
@@ -0,0 +1,172 @@
+/*
+ * Copyright (C) 2012 Stefan Seidel
+ *
+ * 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.
+ */
+
+#define LOG_TAG "lights"
+
+#include <cutils/log.h>
+
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <pthread.h>
+
+#include <hardware/lights.h>
+#include <cutils/properties.h>
+
+/******************************************************************************/
+
+static pthread_once_t g_init = PTHREAD_ONCE_INIT;
+static pthread_mutex_t g_lock = PTHREAD_MUTEX_INITIALIZER;
+static int max_brightness = 255;
+static char brightness_file[PROPERTY_VALUE_MAX] = { '\0' };
+
+char const*const LLP_BRIGHTNESS_FILE     = "backlight.brightness_file";
+char const*const LLP_MAX_BRIGHTNESS_FILE = "backlight.max_brightness_file";
+char const*const LLP_MAX_BRIGHTNESS      = "backlight.max_brightness";
+
+void init_globals(void)
+{
+    pthread_mutex_init(&g_lock, NULL);
+}
+
+static int write_int(char* path, int value)
+{
+    int fd;
+    static int already_warned = 0;
+
+    fd = open(path, O_RDWR);
+    if (fd >= 0) {
+        char buffer[20];
+        int bytes = sprintf(buffer, "%d\n", value);
+        int amt = write(fd, buffer, bytes);
+        close(fd);
+        return amt == -1 ? -errno : 0;
+    } else {
+        if (already_warned == 0) {
+            LOGE("write_int failed to open %s\n", path);
+            already_warned = 1;
+        }
+        return -errno;
+    }
+}
+
+static int read_int(char* path)
+{
+    int fd;
+
+    fd = open(path, O_RDONLY);
+    if (fd >= 0) {
+        char buffer[3];
+        int amt = read(fd, buffer, 3);
+        close(fd);
+        if (amt <= 0) return -errno;
+        int ret = -1;
+        amt = sscanf(buffer, "%d", &ret);
+        return amt == -1 ? -errno : ret;
+    }
+    return -errno;
+}
+
+static int rgb_to_brightness16(struct light_state_t const* state)
+{
+    int color = state->color & 0x00ffffff;
+    return ((77*((color>>16)&0x00ff)) + (150*((color>>8)&0x00ff)) + (29*(color&0x00ff)));
+}
+
+static int set_light_backlight(struct light_device_t* dev, struct light_state_t const* state)
+{
+    int err = 0;
+    int brightness = rgb_to_brightness16(state) / (65536 / (max_brightness + 1));
+    LOGV("Setting display brightness to %d", brightness);
+
+    pthread_mutex_lock(&g_lock);
+    err = write_int(brightness_file, (brightness));
+    pthread_mutex_unlock(&g_lock);
+
+    return err;
+}
+
+static int close_lights(struct light_device_t *dev)
+{
+    free(dev);
+    return 0;
+}
+
+
+static int open_lights(const struct hw_module_t* module, char const* name, struct hw_device_t** device)
+{
+    int (*set_light)(struct light_device_t* dev,
+            struct light_state_t const* state);
+
+    if (0 == strcmp(LIGHT_ID_BACKLIGHT, name)) {
+        set_light = set_light_backlight;
+        char max_b_file[PROPERTY_VALUE_MAX] = { '\0' };
+        if (property_get(LLP_MAX_BRIGHTNESS, max_b_file, NULL)) {
+            if (!sscanf(max_b_file, "%d", &max_brightness)) {
+                LOGE("%s system property is set to '%s', this could not be parsed as an integer!", LLP_MAX_BRIGHTNESS, max_b_file);
+                return -EINVAL;
+            }
+        } else {
+            if (property_get(LLP_MAX_BRIGHTNESS_FILE, max_b_file, NULL)) {
+                max_brightness = read_int(max_b_file);
+            } else {
+                LOGE("%s system property not set", LLP_MAX_BRIGHTNESS_FILE);
+                return -EINVAL;
+            }
+        }
+        LOGV("Read max display brightness of %d", max_brightness);
+        if (max_brightness < 1) {
+            max_brightness = 255;
+        }
+        if (!property_get(LLP_BRIGHTNESS_FILE, brightness_file, NULL)) {
+            LOGE("%s system property not set", LLP_BRIGHTNESS_FILE);
+            return -EINVAL;
+        }
+    } else {
+        return -EINVAL;
+    }
+
+    pthread_once(&g_init, init_globals);
+
+    struct light_device_t *dev = malloc(sizeof(struct light_device_t));
+    memset(dev, 0, sizeof(*dev));
+
+    dev->common.tag = HARDWARE_DEVICE_TAG;
+    dev->common.close = (int (*)(struct hw_device_t*))close_lights;
+    dev->common.module = (struct hw_module_t*)module;
+    dev->common.version = 0;
+    dev->set_light = set_light;
+
+    *device = (struct hw_device_t*)dev;
+    return 0;
+}
+
+
+static struct hw_module_methods_t lights_module_methods = {
+    .open = open_lights,
+};
+
+const struct hw_module_t HAL_MODULE_INFO_SYM = {
+    .tag = HARDWARE_MODULE_TAG,
+    .version_major = 1,
+    .version_minor = 0,
+    .id = LIGHTS_HARDWARE_MODULE_ID,
+    .name = "Generic sysfs liblights implementation",
+    .author = "Stefan Seidel",
+    .methods = &lights_module_methods,
+};