162306a36Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0-only
262306a36Sopenharmony_ci
362306a36Sopenharmony_ci#include <stdio.h>
462306a36Sopenharmony_ci#include <errno.h>
562306a36Sopenharmony_ci#include <stdlib.h>
662306a36Sopenharmony_ci#include <string.h>
762306a36Sopenharmony_ci#include <sys/types.h>
862306a36Sopenharmony_ci#include <sys/stat.h>
962306a36Sopenharmony_ci#include <fcntl.h>
1062306a36Sopenharmony_ci#include <unistd.h>
1162306a36Sopenharmony_ci
1262306a36Sopenharmony_ci#include "cpupower_intern.h"
1362306a36Sopenharmony_ci#include "acpi_cppc.h"
1462306a36Sopenharmony_ci
1562306a36Sopenharmony_ci/* ACPI CPPC sysfs access ***********************************************/
1662306a36Sopenharmony_ci
1762306a36Sopenharmony_cistatic int acpi_cppc_read_file(unsigned int cpu, const char *fname,
1862306a36Sopenharmony_ci			       char *buf, size_t buflen)
1962306a36Sopenharmony_ci{
2062306a36Sopenharmony_ci	char path[SYSFS_PATH_MAX];
2162306a36Sopenharmony_ci
2262306a36Sopenharmony_ci	snprintf(path, sizeof(path), PATH_TO_CPU "cpu%u/acpi_cppc/%s",
2362306a36Sopenharmony_ci		 cpu, fname);
2462306a36Sopenharmony_ci	return cpupower_read_sysfs(path, buf, buflen);
2562306a36Sopenharmony_ci}
2662306a36Sopenharmony_ci
2762306a36Sopenharmony_cistatic const char * const acpi_cppc_value_files[] = {
2862306a36Sopenharmony_ci	[HIGHEST_PERF] = "highest_perf",
2962306a36Sopenharmony_ci	[LOWEST_PERF] = "lowest_perf",
3062306a36Sopenharmony_ci	[NOMINAL_PERF] = "nominal_perf",
3162306a36Sopenharmony_ci	[LOWEST_NONLINEAR_PERF] = "lowest_nonlinear_perf",
3262306a36Sopenharmony_ci	[LOWEST_FREQ] = "lowest_freq",
3362306a36Sopenharmony_ci	[NOMINAL_FREQ] = "nominal_freq",
3462306a36Sopenharmony_ci	[REFERENCE_PERF] = "reference_perf",
3562306a36Sopenharmony_ci	[WRAPAROUND_TIME] = "wraparound_time"
3662306a36Sopenharmony_ci};
3762306a36Sopenharmony_ci
3862306a36Sopenharmony_ciunsigned long acpi_cppc_get_data(unsigned int cpu, enum acpi_cppc_value which)
3962306a36Sopenharmony_ci{
4062306a36Sopenharmony_ci	unsigned long long value;
4162306a36Sopenharmony_ci	unsigned int len;
4262306a36Sopenharmony_ci	char linebuf[MAX_LINE_LEN];
4362306a36Sopenharmony_ci	char *endp;
4462306a36Sopenharmony_ci
4562306a36Sopenharmony_ci	if (which >= MAX_CPPC_VALUE_FILES)
4662306a36Sopenharmony_ci		return 0;
4762306a36Sopenharmony_ci
4862306a36Sopenharmony_ci	len = acpi_cppc_read_file(cpu, acpi_cppc_value_files[which],
4962306a36Sopenharmony_ci				  linebuf, sizeof(linebuf));
5062306a36Sopenharmony_ci	if (len == 0)
5162306a36Sopenharmony_ci		return 0;
5262306a36Sopenharmony_ci
5362306a36Sopenharmony_ci	value = strtoull(linebuf, &endp, 0);
5462306a36Sopenharmony_ci
5562306a36Sopenharmony_ci	if (endp == linebuf || errno == ERANGE)
5662306a36Sopenharmony_ci		return 0;
5762306a36Sopenharmony_ci
5862306a36Sopenharmony_ci	return value;
5962306a36Sopenharmony_ci}
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