ACPI: CPPC: Modify cppc_get_auto_sel_caps() to cppc_get_auto_sel()

Modify cppc_get_auto_sel_caps() to cppc_get_auto_sel(). Using a
cppc_perf_caps to carry the value is unnecessary.

Add a check to ensure the pointer 'enable' is not null.

Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Signed-off-by: Lifeng Zheng <zhenglifeng1@huawei.com>
Reviewed-by: Mario Limonciello <mario.limonciello@amd.com>
Link: https://patch.msgid.link/20250411093855.982491-8-zhenglifeng1@huawei.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Author: Lifeng Zheng

drivers/acpi/cppc_acpi.c

@@ -1602,23 +1602,27 @@ int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable)
 EXPORT_SYMBOL_GPL(cppc_set_epp_perf);
 
 /**
- * cppc_get_auto_sel_caps - Read autonomous selection register.
- * @cpunum : CPU from which to read register.
- * @perf_caps : struct where autonomous selection register value is updated.
+ * cppc_get_auto_sel() - Read autonomous selection register.
+ * @cpu: CPU from which to read register.
+ * @enable: Return address.
  */
-int cppc_get_auto_sel_caps(int cpunum, struct cppc_perf_caps *perf_caps)
+int cppc_get_auto_sel(int cpu, bool *enable)
 {
 	u64 auto_sel;
 	int ret;
 
-	ret = cppc_get_reg_val(cpunum, AUTO_SEL_ENABLE, &auto_sel);
+	if (enable == NULL)
+		return -EINVAL;
+
+	ret = cppc_get_reg_val(cpu, AUTO_SEL_ENABLE, &auto_sel);
 	if (ret)
 		return ret;
 
-	perf_caps->auto_sel = (bool)auto_sel;
+	*enable = (bool)auto_sel;
+
 	return 0;
 }
-EXPORT_SYMBOL_GPL(cppc_get_auto_sel_caps);
+EXPORT_SYMBOL_GPL(cppc_get_auto_sel);
 
 /**
  * cppc_set_auto_sel - Write autonomous selection register.

drivers/cpufreq/amd-pstate.c

@@ -417,6 +417,7 @@ static int shmem_init_perf(struct amd_cpudata *cpudata)
 	struct cppc_perf_caps cppc_perf;
 	union perf_cached perf = READ_ONCE(cpudata->perf);
 	u64 numerator;
+	bool auto_sel;
 
 	int ret = cppc_get_perf_caps(cpudata->cpu, &cppc_perf);
 	if (ret)
@@ -438,7 +439,7 @@ static int shmem_init_perf(struct amd_cpudata *cpudata)
 	if (cppc_state == AMD_PSTATE_ACTIVE)
 		return 0;
 
-	ret = cppc_get_auto_sel_caps(cpudata->cpu, &cppc_perf);
+	ret = cppc_get_auto_sel(cpudata->cpu, &auto_sel);
 	if (ret) {
 		pr_warn("failed to get auto_sel, ret: %d\n", ret);
 		return 0;

include/acpi/cppc_acpi.h

@@ -159,7 +159,7 @@ extern int cpc_read_ffh(int cpunum, struct cpc_reg *reg, u64 *val);
 extern int cpc_write_ffh(int cpunum, struct cpc_reg *reg, u64 val);
 extern int cppc_get_epp_perf(int cpunum, u64 *epp_perf);
 extern int cppc_set_epp_perf(int cpu, struct cppc_perf_ctrls *perf_ctrls, bool enable);
-extern int cppc_get_auto_sel_caps(int cpunum, struct cppc_perf_caps *perf_caps);
+extern int cppc_get_auto_sel(int cpu, bool *enable);
 extern int cppc_set_auto_sel(int cpu, bool enable);
 extern int amd_get_highest_perf(unsigned int cpu, u32 *highest_perf);
 extern int amd_get_boost_ratio_numerator(unsigned int cpu, u64 *numerator);
@@ -229,11 +229,11 @@ static inline int cppc_get_epp_perf(int cpunum, u64 *epp_perf)
 {
 	return -EOPNOTSUPP;
 }
-static inline int cppc_set_auto_sel(int cpu, bool enable)
+static inline int cppc_get_auto_sel(int cpu, bool *enable)
 {
 	return -EOPNOTSUPP;
 }
-static inline int cppc_get_auto_sel_caps(int cpunum, struct cppc_perf_caps *perf_caps)
+static inline int cppc_set_auto_sel(int cpu, bool enable)
 {
 	return -EOPNOTSUPP;
 }