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| #include <jni.h>
| #include <string>
| #include <stdio.h>
| #include <stdlib.h>
| #include <sys/types.h>
| #include <sys/stat.h>
| #include <fcntl.h>
| #include <unistd.h>
| #include <string.h>
| #include <errno.h>
| #include <android/log.h>
| #define TAG "BuzzerApp"
| #define LOGI(fmt, args...) __android_log_print(ANDROID_LOG_INFO, TAG, fmt, ##args)
| #define LOGD(fmt, args...) __android_log_print(ANDROID_LOG_DEBUG, TAG, fmt, ##args)
| #define LOGE(fmt, args...) __android_log_print(ANDROID_LOG_ERROR, TAG, fmt, ##args)
|
| static char pwm_path[100];
|
| extern "C"
| JNIEXPORT jint JNICALL
| Java_com_example_serial_BuzzerControl_openPwm(JNIEnv *env, jclass clazz, jstring id) {
| // TODO: implement openPwm()
| char *id_native;
| char temp[100];
| int fd;
| id_native = (char *)env->GetStringUTFChars(id, 0);
| memset(pwm_path, 0, sizeof (pwm_path));
| snprintf(pwm_path, sizeof (pwm_path), "/sys/class/pwm/pwmchip%s/pwm0", id_native);
|
| memset(temp, 0, sizeof (temp));
| if(access(pwm_path, F_OK))
| {
| snprintf(temp, sizeof (temp), "/sys/class/pwm/pwmchip%s/export", id_native);
| fd = open(temp, O_WRONLY);
| if(fd < 0)
| {
| LOGE("open %s error:%s\n", temp, strerror(errno));
| return -1;
| }
|
| if(1 != write(fd, "0", 1))
| {
| LOGE("Write '0' to pwmchip%s/export error\n", id_native);
| close(fd);
| return -2;
| }
| close(fd);
| }
| env->ReleaseStringUTFChars(id, id_native);
| return 0;
| }
|
|
