diff --git a/tools/power/cpupower/lib/cpuidle.c b/tools/power/cpupower/lib/cpuidle.c
index f2c1139adf71..2fcb343d8e75 100644
--- a/tools/power/cpupower/lib/cpuidle.c
+++ b/tools/power/cpupower/lib/cpuidle.c
@@ -150,6 +150,7 @@ unsigned long long cpuidle_state_get_one_value(unsigned int cpu,
 	if (len == 0)
 		return 0;
 
+	errno = 0;
 	value = strtoull(linebuf, &endp, 0);
 
 	if (endp == linebuf || errno == ERANGE)
@@ -193,8 +194,7 @@ static char *cpuidle_state_get_one_string(unsigned int cpu,
 	if (result == NULL)
 		return NULL;
 
-	if (result[strlen(result) - 1] == '\n')
-		result[strlen(result) - 1] = '\0';
+	result[strcspn(result, "\n")] = '\0';
 
 	return result;
 }
@@ -366,8 +366,7 @@ static char *sysfs_cpuidle_get_one_string(enum cpuidle_string which)
 	if (result == NULL)
 		return NULL;
 
-	if (result[strlen(result) - 1] == '\n')
-		result[strlen(result) - 1] = '\0';
+	result[strcspn(result, "\n")] = '\0';
 
 	return result;
 }
diff --git a/tools/power/cpupower/utils/cpufreq-info.c b/tools/power/cpupower/utils/cpufreq-info.c
index 7d3732f5f2f6..5fe01e516817 100644
--- a/tools/power/cpupower/utils/cpufreq-info.c
+++ b/tools/power/cpupower/utils/cpufreq-info.c
@@ -270,7 +270,7 @@ static int get_freq_hardware(unsigned int cpu, unsigned int human)
 {
 	unsigned long freq;
 
-	if (cpupower_cpu_info.caps & CPUPOWER_CAP_APERF)
+	if (!(cpupower_cpu_info.caps & CPUPOWER_CAP_APERF))
 		return -EINVAL;
 
 	freq = cpufreq_get_freq_hardware(cpu);
diff --git a/tools/power/cpupower/utils/cpuidle-info.c b/tools/power/cpupower/utils/cpuidle-info.c
index e0d17f0de3fe..81b4763a97d6 100644
--- a/tools/power/cpupower/utils/cpuidle-info.c
+++ b/tools/power/cpupower/utils/cpuidle-info.c
@@ -111,7 +111,7 @@ static void proc_cpuidle_cpu_output(unsigned int cpu)
 	printf(_("max_cstate:              C%u\n"), cstates-1);
 	printf(_("maximum allowed latency: %lu usec\n"), max_allowed_cstate);
 	printf(_("states:\t\n"));
-	for (cstate = 1; cstate < cstates; cstate++) {
+	for (cstate = 0; cstate < cstates; cstate++) {
 		printf(_("    C%d:                  "
 			 "type[C%d] "), cstate, cstate);
 		printf(_("promotion[--] demotion[--] "));
diff --git a/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c b/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
index 8b42c2f0a5b0..4225eff9833d 100644
--- a/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
+++ b/tools/power/cpupower/utils/idle_monitor/cpuidle_sysfs.c
@@ -70,7 +70,7 @@ static int cpuidle_stop(void)
 			current_count[cpu][state] =
 				cpuidle_state_time(cpu, state);
 			dprint("CPU %d - State: %d - Val: %llu\n",
-			       cpu, state, previous_count[cpu][state]);
+			       cpu, state, current_count[cpu][state]);
 		}
 	}
 	return 0;