diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/hal-backend-power.c | 775 | ||||
| -rw-r--r-- | src/sysfs.c | 129 | ||||
| -rw-r--r-- | src/sysfs.h | 6 |
3 files changed, 910 insertions, 0 deletions
diff --git a/src/hal-backend-power.c b/src/hal-backend-power.c new file mode 100644 index 0000000..c4f52ad --- /dev/null +++ b/src/hal-backend-power.c @@ -0,0 +1,775 @@ +/* + * HAL backend for hal-api-power which is used for PASS daemon + * + * Copyright (c) 2021 Samsung Electronics Co., Ltd. + * + * 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 <limits.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> + +#include <hal/hal-power-interface.h> + +#include "sysfs.h" + +#define BUFF_MAX 255 + +/************************* + * H/W Resource Defintions + */ +#define CPUFREQ_PATH_PREFIX "/sys/devices/system/cpu/" +#define CPUFREQ_CURR_GOVERNOR_PATH_SUFFIX "/cpufreq/scaling_governor" +#define CPUFREQ_AVAIL_GOVERNOR_PATH_SUFFIX "/cpufreq/scaling_available_governors" + +/* + * The cpuinfo_cur_freq indicates the actual operating CPU freqeuncy + * and scaling_cur_freq is the CPU frequency set by the CPUFREQ policy. + */ +#define CPUFREQ_CURR_FREQ_PATH_SUFFIX "/cpufreq/cpuinfo_cur_freq" +#define CPUFREQ_AVAILABLE_MIN_FREQ_PATH_SUFFIX "/cpufreq/cpuinfo_min_freq" +#define CPUFREQ_AVAILABLE_MAX_FREQ_PATH_SUFFIX "/cpufreq/cpuinfo_max_freq" +#define CPUFREQ_MIN_FREQ_PATH_SUFFIX "/cpufreq/scaling_min_freq" +#define CPUFREQ_MAX_FREQ_PATH_SUFFIX "/cpufreq/scaling_max_freq" +#define CPUFREQ_UP_THRESHOLD_PATH_SUFFIX "/cpufreq/ondemand/up_threshold" + +#define CPU_ONLINE_PATH_PREFIX "/sys/devices/system/cpu/cpu" +#define CPU_ONLINE_PATH_SUFFIX "/online" +#define CPU_ONLINE_STATE_ON 1 +#define CPU_ONLINE_STATE_OFF 0 + +#define TMU_PATH_PREFIX "/sys/class/thermal/" +#define TMU_TEMP_PATH_SUFFIX "/temp" +#define TMU_POLICY_PATH_SUFFIX "/policy" +#define TMU_MAX_TEMP_MASK 0xFFFFF + +#define DEVFREQ_BUS_PATH_PREFIX "/sys/class/devfreq/" +#define DEVFREQ_BUS_CURR_GOVERNOR_PATH_SUFFIX "/governor" +#define DEVFREQ_BUS_CURR_FREQ_PATH_SUFFIX "/cur_freq" +#define DEVFREQ_BUS_MIN_FREQ_PATH_SUFFIX "/min_freq" +#define DEVFREQ_BUS_MAX_FREQ_PATH_SUFFIX "/max_freq" +#define DEVFREQ_BUS_AVAILABLE_FREQ_PATH_SUFFIX "/available_frequencies" + +#define FAULT_AROUND_BYTES_PATH "/sys/kernel/debug/fault_around_bytes" + +/************************************************* + * HAL backend implementation for CPU H/W Resource + */ +static int cpufreq_dvfs_get_curr_governor(char *res_name, char *governor) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (!governor)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_CURR_GOVERNOR_PATH_SUFFIX); + + ret = sysfs_read_str(path, governor, BUFF_MAX); + if (ret < 0) + return ret; + + return 0; +} + +static int cpufreq_dvfs_set_curr_governor(char *res_name, char *governor) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (!governor)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_CURR_GOVERNOR_PATH_SUFFIX); + + ret = sysfs_write_str(path, governor); + if (ret < 0) + return ret; + + return 0; +} + +static int cpufreq_dvfs_get_curr_freq(char *res_name) +{ + char path[PATH_MAX]; + int freq, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_CURR_FREQ_PATH_SUFFIX); + + ret = sysfs_read_int(path, &freq); + if (ret < 0) + return ret; + + return freq; +} + +static int cpufreq_dvfs_get_min_freq(char *res_name) +{ + char path[PATH_MAX]; + int freq, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_MIN_FREQ_PATH_SUFFIX); + + ret = sysfs_read_int(path, &freq); + if (ret < 0) + return ret; + + return freq; +} + +static int cpufreq_dvfs_set_min_freq(char *res_name, int freq) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (freq < 0)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_MIN_FREQ_PATH_SUFFIX); + + ret = sysfs_write_int(path, freq); + if (ret < 0) + return ret; + + return 0; +} + +static int cpufreq_dvfs_get_max_freq(char *res_name) +{ + char path[PATH_MAX]; + int freq, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_MAX_FREQ_PATH_SUFFIX); + + ret = sysfs_read_int(path, &freq); + if (ret < 0) + return ret; + + return freq; +} + +static int cpufreq_dvfs_set_max_freq(char *res_name, int freq) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (freq < 0)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_MAX_FREQ_PATH_SUFFIX); + + ret = sysfs_write_int(path, freq); + if (ret < 0) + return ret; + return 0; +} + +static int cpufreq_dvfs_get_available_min_freq(char *res_name) +{ + char path[PATH_MAX]; + int val, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_AVAILABLE_MIN_FREQ_PATH_SUFFIX); + + ret = sysfs_read_int(path, &val); + if (ret < 0) + return ret; + + return val; +} + + +static int cpufreq_dvfs_get_available_max_freq(char *res_name) +{ + char path[PATH_MAX]; + int val, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_AVAILABLE_MAX_FREQ_PATH_SUFFIX); + + ret = sysfs_read_int(path, &val); + if (ret < 0) + return ret; + + return val; +} + +static int cpufreq_dvfs_get_up_threshold(char *res_name) +{ + char path[PATH_MAX]; + int val, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_UP_THRESHOLD_PATH_SUFFIX); + + ret = sysfs_read_int(path, &val); + if (ret < 0) + return ret; + + return val; +} + +static int cpufreq_dvfs_set_up_threshold(char *res_name, int up_threshold) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (up_threshold < 0)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + CPUFREQ_PATH_PREFIX, + res_name, + CPUFREQ_UP_THRESHOLD_PATH_SUFFIX); + + ret = sysfs_write_int(path, up_threshold); + if (ret < 0) + return ret; + + return 0; +} + +static struct pass_resource_dvfs_ops cpufreq_dvfs_ops = { + .get_curr_governor = cpufreq_dvfs_get_curr_governor, + .set_curr_governor = cpufreq_dvfs_set_curr_governor, + .get_curr_freq = cpufreq_dvfs_get_curr_freq, + .get_min_freq = cpufreq_dvfs_get_min_freq, + .set_min_freq = cpufreq_dvfs_set_min_freq, + .get_max_freq = cpufreq_dvfs_get_max_freq, + .set_max_freq = cpufreq_dvfs_set_max_freq, + .get_available_min_freq = cpufreq_dvfs_get_available_min_freq, + .get_available_max_freq = cpufreq_dvfs_get_available_max_freq, + .get_up_threshold = cpufreq_dvfs_get_up_threshold, + .set_up_threshold = cpufreq_dvfs_set_up_threshold, +}; + +static int cpu_hotplug_get_online_state(char *res_name, int cpu) +{ + char path[PATH_MAX]; + int ret, online; + + if ((!res_name)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%d%s", + CPU_ONLINE_PATH_PREFIX, + cpu, + CPU_ONLINE_PATH_SUFFIX); + + ret = sysfs_read_int(path, &online); + if (ret < 0) + return ret; + + return online; +} + +static int cpu_hotplug_set_online_state(char *res_name, int cpu, int on) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name)) + return -EINVAL; + if ((on != CPU_ONLINE_STATE_ON) && (on != CPU_ONLINE_STATE_OFF)) + return -EINVAL; + + /* + * NOTE: Exynos SoC series cannot turn off the CPU0 + * because of h/w design. To prevent the critical problem, + * if someone try to turn off the CPU0, just return without any + * opertaion. + */ + if (on == 0 && cpu == 0) { + return 0; + } + + snprintf(path, PATH_MAX, "%s%d%s", + CPU_ONLINE_PATH_PREFIX, + cpu, + CPU_ONLINE_PATH_SUFFIX); + + ret = sysfs_write_int(path, on); + if (ret < 0) + return ret; + + return 0; +} + +static struct pass_resource_hotplug_ops cpu_hotplus_ops = { + .get_online_state = cpu_hotplug_get_online_state, + .set_online_state = cpu_hotplug_set_online_state, + .get_online_min_num = NULL, + .set_online_min_num = NULL, + .get_online_max_num = NULL, + .set_online_max_num = NULL, +}; + +static int tmu_get_temp(char *res_thermal_name) +{ + char path[PATH_MAX]; + int temp, ret; + + if (!res_thermal_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + TMU_PATH_PREFIX, + res_thermal_name, + TMU_TEMP_PATH_SUFFIX); + + ret = sysfs_read_int(path, &temp); + if (ret < 0) + return ret; + + /* + * Thermal framework provides the current temperature + * as five digits interger like 54430 when temperature is 54.430 + * degrees centigrade. But, Thermal Monitor in Tizen usually + * use two digits interger without decimal point. + * So that round temperature value. It constraints the maximume + * temperature as 1048 degrees centigrade for preventing integer + * overflow. Usually, the embedded device never over 1000 degrees + * centigrade. + */ + return (((temp & TMU_MAX_TEMP_MASK) + 500) / 1000); +} + +static int tmu_get_policy(char *res_thermal_name, char *policy) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_thermal_name) || (!policy)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + TMU_PATH_PREFIX, + res_thermal_name, + TMU_POLICY_PATH_SUFFIX); + + ret = sysfs_read_str(path, policy, BUFF_MAX); + if (ret < 0) + return ret; + + return 0; +} + +static struct pass_resource_tmu_ops tmu_ops = { + .get_temp = tmu_get_temp, + .get_policy = tmu_get_policy, +}; + +/***************************************************** + * HAL backend implementation for BUS/GPU H/W Resource + */ +static int devfreq_dvfs_get_curr_governor(char *res_name, char *governor) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (!governor)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_CURR_GOVERNOR_PATH_SUFFIX); + + ret = sysfs_read_str(path, governor, BUFF_MAX); + if (ret < 0) + return ret; + + return 0; +} + +static int devfreq_dvfs_set_curr_governor(char *res_name, char *governor) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (!governor)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_CURR_GOVERNOR_PATH_SUFFIX); + + ret = sysfs_write_str(path, governor); + if (ret < 0) + return ret; + + return 0; +} + +static int devfreq_dvfs_get_curr_freq(char *res_name) +{ + char path[PATH_MAX]; + int freq, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_CURR_FREQ_PATH_SUFFIX); + + ret = sysfs_read_int(path, &freq); + if (ret < 0) + return ret; + + return freq; +} + +static int devfreq_dvfs_get_min_freq(char *res_name) +{ + char path[PATH_MAX]; + int freq, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_MIN_FREQ_PATH_SUFFIX); + + ret = sysfs_read_int(path, &freq); + if (ret < 0) + return ret; + + return freq; +} + +static int devfreq_dvfs_set_min_freq(char *res_name, int freq) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (freq < 0)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_MIN_FREQ_PATH_SUFFIX); + + ret = sysfs_write_int(path, freq); + if (ret < 0) + return ret; + + return 0; +} + +static int devfreq_dvfs_get_max_freq(char *res_name) +{ + char path[PATH_MAX]; + int freq, ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_MAX_FREQ_PATH_SUFFIX); + + ret = sysfs_read_int(path, &freq); + if (ret < 0) + return ret; + + return freq; +} + +static int devfreq_dvfs_set_max_freq(char *res_name, int freq) +{ + char path[PATH_MAX]; + int ret; + + if ((!res_name) || (freq < 0)) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_MAX_FREQ_PATH_SUFFIX); + + ret = sysfs_write_int(path, freq); + if (ret < 0) + return ret; + return 0; +} + +static int devfreq_dvfs_get_available_min_freq(char *res_name) +{ + char path[PATH_MAX]; + char buf[MAX_BUF_SIZE + 1]; + char *p; + int ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_AVAILABLE_FREQ_PATH_SUFFIX); + + ret = sysfs_read_str(path, buf, MAX_BUF_SIZE); + if (ret < 0) + return ret; + + p = strchr(buf, ' '); + if (p) + *p = '\0'; + + ret = strtoul(buf, NULL, 10); + if (!ret) + return -EINVAL; + + return ret; +} + +static int devfreq_dvfs_get_available_max_freq(char *res_name) +{ + char path[PATH_MAX]; + char buf[MAX_BUF_SIZE + 1]; + char *p; + int ret; + + if (!res_name) + return -EINVAL; + + snprintf(path, PATH_MAX, "%s%s%s", + DEVFREQ_BUS_PATH_PREFIX, + res_name, + DEVFREQ_BUS_AVAILABLE_FREQ_PATH_SUFFIX); + + ret = sysfs_read_str(path, buf, MAX_BUF_SIZE); + if (ret < 0) + return ret; + + p = strrchr(buf, ' '); + p = p ? p + 1 : buf; + + ret = strtoul(p, NULL, 10); + if (!ret) + return -EINVAL; + + return ret; +} + +static struct pass_resource_dvfs_ops devfreq_dvfs_ops = { + .get_curr_governor = devfreq_dvfs_get_curr_governor, + .set_curr_governor = devfreq_dvfs_set_curr_governor, + .get_curr_freq = devfreq_dvfs_get_curr_freq, + .get_min_freq = devfreq_dvfs_get_min_freq, + .set_min_freq = devfreq_dvfs_set_min_freq, + .get_max_freq = devfreq_dvfs_get_max_freq, + .set_max_freq = devfreq_dvfs_set_max_freq, + .get_available_min_freq = devfreq_dvfs_get_available_min_freq, + .get_available_max_freq = devfreq_dvfs_get_available_max_freq, +}; + +/**************************************************** + * HAL backend implementation for Memory H/W Resource + */ +static int memory_get_fault_around_bytes(char *res_name) +{ + int ret, fault_around_bytes; + + if (!res_name) + return -EINVAL; + + ret = sysfs_read_int(FAULT_AROUND_BYTES_PATH, &fault_around_bytes); + if (ret < 0) + return ret; + + return fault_around_bytes; +} + +static int memory_set_fault_around_bytes(char *res_name, + int fault_around_bytes) +{ + int ret; + + if ((!res_name) || (fault_around_bytes <= 0)) + return -EINVAL; + + ret = sysfs_write_int(FAULT_AROUND_BYTES_PATH, fault_around_bytes); + if (ret < 0) + return ret; + + return 0; +} + +/************************ + * HAL backend power data + */ +static int power_init(void **data) +{ + hal_backend_power_funcs *power_funcs = NULL; + struct pass_resource_cpu *cpu = NULL; + struct pass_resource_bus *bus = NULL; + struct pass_resource_gpu *gpu = NULL; + struct pass_resource_memory *memory = NULL; + int ret; + + /* Allocate memory */ + power_funcs = calloc(1, sizeof(hal_backend_power_funcs)); + if (!power_funcs) + return -ENOMEM; + + cpu = calloc(1, sizeof(struct pass_resource_cpu)); + if (!cpu) { + ret = -ENOMEM; + goto err_funcs; + } + + bus = calloc(1, sizeof(struct pass_resource_bus)); + if (!bus) { + ret = -ENOMEM; + goto err_cpu; + } + + gpu = calloc(1, sizeof(struct pass_resource_gpu)); + if (!gpu) { + ret = -ENOMEM; + goto err_bus; + } + + memory = calloc(1, sizeof(struct pass_resource_memory)); + if (!memory) { + ret = -ENOMEM; + goto err_gpu; + } + + /* Initialize each h/w resource */ + cpu->dvfs = cpufreq_dvfs_ops; + cpu->hotplug = cpu_hotplus_ops; + cpu->tmu = tmu_ops; + + bus->dvfs = devfreq_dvfs_ops; + bus->tmu = tmu_ops; + + gpu->dvfs = devfreq_dvfs_ops; + gpu->tmu = tmu_ops; + + memory->get_fault_around_bytes = memory_get_fault_around_bytes; + memory->set_fault_around_bytes = memory_set_fault_around_bytes; + + /* Initialize hal_backend_power_funcs */ + power_funcs->cpu = cpu; + power_funcs->bus = bus; + power_funcs->gpu = gpu; + power_funcs->memory = memory; + + *data = (void *)power_funcs; + + return 0; + +err_gpu: + if (gpu) + free(gpu); +err_bus: + if (bus) + free(bus); +err_cpu: + if (cpu) + free(cpu); +err_funcs: + free(power_funcs); + + return ret; +} + +static int power_exit(void *data) +{ + hal_backend_power_funcs *funcs; + + if (!data) + return -EINVAL; + + funcs = (hal_backend_power_funcs *)data; + + if (funcs->cpu) + free(funcs->cpu); + if (funcs->bus) + free(funcs->bus); + if (funcs->gpu) + free(funcs->gpu); + if (funcs->memory) + free(funcs->memory); + + free(funcs); + + return 0; +} + +hal_backend hal_backend_power_data = { + .name = "power-cpu", + .vendor = "", + .abi_version = HAL_ABI_VERSION_TIZEN_6_5, + .init = power_init, + .exit = power_exit, +}; diff --git a/src/sysfs.c b/src/sysfs.c new file mode 100644 index 0000000..23768ce --- /dev/null +++ b/src/sysfs.c @@ -0,0 +1,129 @@ +/* + * PASS (Power Aware System Service) + * + * Copyright (c) 2017 Samsung Electronics Co., Ltd. + * + * 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 <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include "sysfs.h" + +static int sysfs_read_buf(char *path, char *buf, int len) +{ + int r, fd; + + if ((!path) || (!buf) || (len < 0)) + return -EINVAL; + + fd = open(path, O_RDONLY); + if (fd == -1) + return -ENOENT; + + r = read(fd, buf, len); + close(fd); + + if (r < 0) + return r; + if (r > len) + return -EIO; + + buf[r] = '\0'; + + return 0; +} + +static int sysfs_write_buf(char *path, char *buf) +{ + int w, fd; + + if ((!path) || (!buf)) + return -EINVAL; + + fd = open(path, O_WRONLY); + if (fd == -1) + return -ENOENT; + + w = write(fd, buf, strlen(buf)); + close(fd); + + if (w < 0) + return w; + + return 0; +} + +int sysfs_read_int(char *path, int *val) +{ + char buf[MAX_BUF_SIZE + 1]; + int r; + + if ((!path) || (!val)) + return -EINVAL; + + r = sysfs_read_buf(path, buf, MAX_BUF_SIZE); + if (r < 0) + return r; + + *val = atoi(buf); + return 0; +} + +int sysfs_read_str(char *path, char *str, int len) +{ + int r; + + if ((!path) || (!str) || (len <= 0)) + return -EINVAL; + + r = sysfs_read_buf(path, str, len); + if (r < 0) + return r; + + return 0; +} + +int sysfs_write_int(char *path, int val) +{ + char buf[MAX_BUF_SIZE + 1]; + int w; + + if (!path) + return -EINVAL; + + snprintf(buf, MAX_BUF_SIZE, "%d", val); + w = sysfs_write_buf(path, buf); + if (w < 0) + return w; + + return 0; +} + +int sysfs_write_str(char *path, char *str) +{ + int w; + + if ((!path) || (!str)) + return -EINVAL; + + w = sysfs_write_buf(path, str); + if (w < 0) + return w; + + return 0; +} diff --git a/src/sysfs.h b/src/sysfs.h new file mode 100644 index 0000000..174804f --- /dev/null +++ b/src/sysfs.h @@ -0,0 +1,6 @@ +#define MAX_BUF_SIZE 255 + +int sysfs_read_int(char *path, int *val); +int sysfs_read_str(char *path, char *str, int len); +int sysfs_write_int(char *path, int val); +int sysfs_write_str(char *path, char *str); |