diff options
Diffstat (limited to 'liblights/lights_helper.c')
-rw-r--r-- | liblights/lights_helper.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/liblights/lights_helper.c b/liblights/lights_helper.c new file mode 100644 index 0000000..c3406ab --- /dev/null +++ b/liblights/lights_helper.c @@ -0,0 +1,148 @@ +/* + * 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 <fcntl.h> +#include <stdlib.h> +#include <string.h> +#include <cutils/log.h> +#include <sys/stat.h> +#include <sys/types.h> + +#include <liblights/samsung_lights_helper.h> + +/* + * Reads an Integer from a file. + * + * @param path The absolute path string. + * @return The Integer with decimal base, -1 on error. + */ +int read_int(char const *path) +{ + int fd, len; + int num_bytes = 10; + char buf[11]; + int retval; + + fd = open(path, O_RDONLY); + if (fd < 0) { + ALOGE("%s: failed to open %s\n", __func__, path); + goto fail; + } + + len = read(fd, buf, num_bytes - 1); + if (len < 0) { + ALOGE("%s: failed to read from %s\n", __func__, path); + goto fail; + } + + buf[len] = '\0'; + close(fd); + + // no endptr, decimal base + retval = strtol(buf, NULL, 10); + return retval == 0 ? -1 : retval; + +fail: + if (fd >= 0) + close(fd); + return -1; +} + +/* + * Writes an Integer to a file. + * + * @param path The absolute path string. + * @param value The Integer value to be written. + * @return 0 on success, -1 or errno on error. + */ +int write_int(char const *path, const int value) +{ + int fd; + static int already_warned; + + already_warned = 0; + + ALOGV("write_int: path %s, value %d", path, value); + 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) { + ALOGE("write_int failed to open %s\n", path); + already_warned = 1; + } + return -errno; + } +} + +/* + * Set the current button brightness via sysfs. + * + * @param brightness The brightness value. + * @return 0 on success, -1 or errno on error. + */ +inline int set_cur_button_brightness(const int brightness) +{ + return write_int(BUTTON_BRIGHTNESS_NODE, brightness); +} + +/* + * Read the current panel brightness from sysfs. + * + * @return The brightness as Integer, -1 on error. + */ +inline int get_cur_panel_brightness() +{ + return read_int(PANEL_BRIGHTNESS_NODE); +} + +/* + * Read the maximum panel brightness from sysfs. + * + * @return The brightness as Integer, -1 on error. + */ +inline int get_max_panel_brightness() +{ + return read_int(PANEL_MAX_BRIGHTNESS_NODE); +} + +/* + * Set the current panel brightness via sysfs. + * + * @param brightness The (scaled) brightness value. + * @return 0 on success, -1 or errno on error. + */ +inline int set_cur_panel_brightness(const int brightness) +{ + return write_int(PANEL_BRIGHTNESS_NODE, brightness); +} + +/* + * Set the maximum panel brightness via sysfs. + * + * @param brightness The brightness value. + * @return 0 on success, -1 or errno on error. + */ +inline int set_max_panel_brightness(const int brightness) +{ + return write_int(PANEL_MAX_BRIGHTNESS_NODE, brightness); +} |